EFFECT OF MAGNETIC TREATMENT ON IRRIGATION WATER QUALITY, SOIL PROPERTIES AND GROWTH OF SUNFLOWER CROP. Master of Science (Agriculture) Soil Science

Transcription

1 EFFECT OF MAGNETIC TREATMENT ON IRRIGATION WATER QUALITY, SOIL PROPERTIES AND GROWTH OF SUNFLOWER CROP Thesis submitted to the University of Agricultural Sciences, Dharwad In partial fulfillment of the requirements for the Degree of Master of Science (Agriculture) In Soil Science By ASHWINI H. GUDIGAR DEPARTMENT OF SOIL SCIENCE AND AGRICULTURAL CHEMISTRY COLLEGE OF AGRICULTURE, DHARWAD UNIVERSITY OF AGRICULTURAL SCIENCES, DHARWAD JULY, 2013

2 ADVISORY COMMITTEE DHARWAD JULY, 2013 (MANJUNATHA HEBBARA) MAJOR ADVISOR Approved by : Chairman : Members : (MANJUNATHA HEBBARA) 1. (M.V. MANJUNATHA) 2. (S.S. GUNDLUR) 3. (R.BASAVARAJAPPA)

3 CONTENTS Sl. No. Chapter Particulars CERTIFICATE ACKNOWLEDGEMENT LIST OF TABLES LIST OF FIGURES LIST OF PLATES LIST OF APPENDIX 1. INTRODUCTION 2. REVIEW OF LITERATURE 2.1 Effect of magnetic treatment on irrigation water quality 2.2 Effect of magnetized water on soil properties 2.3 Effect of magnetized water on germination and growth 2.4 Effect of magnetized water on yield and quality parameters 2.5 Effect of magnetized water on physiological properties 3. MATERIAL AND METHODS 3.1 Preparation of saline irrigation waters 3.2 Magnetization of irrigation water 3.3 Methodology for first objective 3.4 Methodology for second objective 3.5 Methodology for third objective 3.6 Methodology for fourth objective 3.7 Analysis of irrigation water quality 3.8 Soil analysis 3.9 Growth parameters of sunflower 3.10 Plant analysis 3.11 Statistical analysis Contd.

4 Sl. No. Chapter Particulars 4. EXPERIMENTAL RESULTS 4.1 Effect of magnetic treatment on irrigation water quality 4.2 Effect of magnetized water on soil properties 4.3 Effect of magnetized water on leaching efficiency of salts 4.4 Effect of magnetic water treatment on germination and early growth of sunflower 5 DISCUSSION 5.1 Effect of magnetic treatment on irrigation water quality 5.2 Effect of magnetized water on soil properties 5.3 Effect of magnetized water on leaching efficiency of salts 5.4 Effect of magnetic treatment on growth of sunflower 6 SUMMARY AND CONCLUSIONS REFERENCES APPENDIX

5 LIST OF TABLES Table No. Title 1. Effect of magnetic treatment on ph of irrigation waters 2. Effect of magnetic treatment on salinity of irrigation waters 3. Effect of magnetic treatment on calcium content of irrigation waters 4. Effect of magnetic treatment on magnesium content of irrigation waters 5. Effect of magnetic treatment on sodium content of irrigation waters 6. Effect of magnetic treatment on sodium adsorption ratio of irrigation waters 7. Effect of magnetic treatment on bicarbonate of irrigation waters 8. Effect of magnetic treatment on residual sodium carbonate of irrigation waters 9. Effect of magnetic treatment on chloride content of irrigation waters 10. Effect of magnetized water on soil ph 11. Effect of magnetized water on soil salinity 12. Effect of magnetized water on soil exchangeable calcium 13. Effect of magnetized water on soil exchangeable magnesium 14. Effect of magnetized water on soil exchangeable sodium Effect of magnetized water on soil exchangeable sodium percentage Effect of magnetized water on soil water soluble calcium Effect of magnetized water on soil water soluble magnesium Effect of magnetized water on soil water soluble sodium Effect of magnetized water on soil water soluble chloride Effect of magnetized water on soil clay dispersion Effect of leaching with magnetized water on soil salinity Effect of leaching with magnetized water on EC of leachate Effect of magnetized water on germination of sunflower seeds Effect of magnetized water on plant height of sunflower at 30 and 45 DAS Effect of magnetized water on dry weight (g plant -1 ) of sunflower plants Effect of magnetized water on sodium content in sunflower plant Effect of magnetized water on potassium content in sunflower plant Effect of magnetized water on K/ Na ratio in sunflower plant

6 LIST OF FIGURES Figure No. Title 1. Schematic diagram of magnetic fields and direction of water flow during the magnetic treatment 2. Effect of magnetic treatment on ph of irrigation waters 3. Effect of magnetic treatment on salinity (EC, ds m -1 ) of irrigation waters 4. Effect of magnetic treatment on calcium, magnesium and sodium content (me L -1 ) of irrigation waters 5. Effect of magnetic treatment on SAR (me L -1 ) of irrigation waters 6. Effect of magnetic treatment on chloride content (me L -1 ) of irrigation waters 7. Effect of magnetic treatment on bicarbonate content (me L -1 ) of irrigation waters 8. Effect of magnetic treatment on RSC (me L -1 ) of irrigation waters 9. Effect of magnetized water on soil ph and salinity (EC 2.5, ds m -1 ) at three pore volumes 10. Effect of magnetized water on soil ph and salinity (EC 2.5, ds m -1 ) at five pore volumes 11. Effect of magnetized water on exchangeable calcium, magnesium and sodium (me 100 g -1 soil) at three pore volumes 12. Effect of magnetized water on exchangeable calcium, magnesium and sodium (me 100 g -1 soil) at five pore volumes 13. Effect of magnetized water on exchangeable sodium percentage 14. Effect of magnetized water on water soluble calcium, magnesium and sodium (me L -1 ) at three pore volumes 15. Effect of magnetized water on water soluble calcium, magnesium and sodium (me L -1 ) at five pore volumes 16. Effect of magnetized water on water soluble chloride (me L -1 ) 17. Effect of magnetized water on clay dispersion (%) 18. Effect of leaching with magnetized water on EC of soil and leachate 19. Effect of magnetized water on germination percentage and plant height (cm) of sunflower 20. Effect of magnetized water on dry weight (g plant -1 ) of sunflower plant 21. Effect of magnetized water on sodium and potassium content in sunflower plant

7 LIST OF PLATES Plate No. Title 1. The magnetic device used to magnetize irrigation waters 2. A view of column studies 3. Growth of sunflower at 30 days after sowing 4. Growth of sunflower at 45 days after sowing LIST OF APPENDIX Appendix No. Title I. Methods used for analysis

8 INTRODUCTION Magnetized water is water passed through a magnetic field. Many physio-chemical changes are reported to take place in the water when treated magnetically, including changes in viscosity, boiling point, magnetic susceptibility, electrical conductivity and surface tension. It is being projected as an inexpensive and eco- friendly water treatment that has no energy requirements. Water is a difficult substance to examine properties for, as it carries a variety of foreign particles in the form of micro contaminants and other dissolved solids. This adds to the confusion about magnetized water with many claiming that certain chemicals in the water determine the success rates of the treatments. Around the world, in different laboratories, the water being treated varies from experiment to experiment, except when using distilled water. treatment of water is based on the principle of magneto-hydrodynamics, where electrical energy is added to charged particles in water that contains ions and small solid particles with electrostatic charges by a magnetic field. The energy is produced by the momentum of the particles and remains attached to the particles as surface energy (Gehr et al., 1995). Applying a magnetic field to natural water causes a redistribution of flow energy because of a momentum change of charged particles. All the particles and ions are electrically charged such that when magnetic fields are introduced convection and induced currents cause the liquid to spin. This movement then effects changes in gas content and the amount of salt crystallization (Sherkliff, 1965). The quick change of the magnetic field in a properly designed magnetic apparatus loosens hydrate layers and films in a moving liquid, thus enabling coagulation and coalescence (Bogatin et al., 1999). technology can become a useful tool, as proved by many researchers, to tackle problems related to reduced crop productivity due to use of saline water in agriculture. Shrinking surface fresh water resources, increasing salinity of ground water, rising demand for water by urban and farming communities have made it difficult for planners to manage this precious resource to the satisfaction of all stakeholders. At present, about 85 per cent of India s fresh water resources are being utilized in agriculture and remaining 15 per cent in industrial and domestic sector (Minhas and Samra, 2004). This pattern of use of water is gradually changing. The demand for the domestic and industrial sectors is likely to increase to 30% by With the curtailment of the fresh water supplies (mainly surface water), agriculture will increasingly depend upon marginal quality waters, mainly ground waters, for irrigation. Ground water is being increasingly exploited to meet the water requirement of the crops or to bridge the shortfall of water available from other sources viz a viz the water required by the crops. However, per cent of the ground water aquifers especially in the states of Rajasthan, Haryana and Uttar Pradesh are considered unfit for irrigation as their use of likely to build up of salinity, sodicity or toxicity in soils. In north Karnataka the ground water was affected up to 65, 10 and 25 per cent by salinity, sodicity and toxicity respectively, out of total ground water. Crop production with poor quality waters, especially loaded with salts has been a challenge all these years. Concerted efforts have been made in this regard and several recommendations have been made for successful crop production using such waters. The research on this aspect has taken a long leap in countries with very scanty fresh water resource like Israel. Use of less expensive and more pro-ecological means such as electrical and magnetic fields have been explored to minimize the effect of salinity on crop. The prospect of using magnetic technologies in agriculture is not a new concept, though not widely accepted by many. Several beneficial effects of magnetized water have been documented. Magnetized water is reported to increase crop yield, induce seed germination and benefit the health of livestock. The literature suggest that magnetized water used for irrigation can improve water productivity and thus help to conserve water resource (Duarte et al., 1997). ally treated water has also been found to be effective in preventing and removing scale deposits in irrigation pipes and water containing structures and also increase the levels of CO 2 and H + in soils comparable to the addition of fertilizers. ally treated water is reported to save on an average, 20 per cent water with 10 per cent increased yields (Lin and Yotvat, 1990). This treatment would be beneficial in today s world with water scarcity and food shortages in many regions. Bogatin et al. (1999) reported an increase in crop yield by 10 to 15 per cent under magnetic water treatment due to (a) leaching of superfluous salts (b)

9 better permeability of irrigated water and (c) better dissociation of mineral fertilizers. Increased permeability of water reduced the amount of water required for each irrigation event. Magnetized water has been used as an effective means for soil desalinization. Magnetized water applied to salty soil is reported to break down salt crystals and help in faster leaching of salts. In India, the magnetic treatment has not been much explored for salinity management as like other management options including soil, crop and nutrition. With this background, the present study was conducted with the following objectives: 1. To study the effect of magnetic treatment on irrigation water quality 2. To study the effect of magnetized water on soil properties 3. To study the effect of magnetized water on leaching efficiency of salts 4. To study the effect of magnetized water on germination and early growth of sunflower

10 REVIEW OF LITERATURE Magnetized water is water passed through a magnetic field. Many physico-chemical changes are reported to take place in the water when treated magnetically, including changes in viscosity, boiling point, magnetic susceptibility, electrical conductivity and surface tension. Magnetized water is reported to increase crop yield, induce seed germination and benefit the health of livestock and it is found to be effective for preventing and removing scale deposits in pipes and water containing structures and also increase the levels of CO 2 and H + in soils comparable to the addition of fertilizers. Magnetized water has been used as an effective means for soil desalinization. When applied to salty soil, magnetic field breaks down the salt crystals and helps in faster leaching of salts. The literature pertaining to the effect of magnetic treatment on irrigation water quality, soil properties and crop is reviewed in this chapter under the following headings: 2.1 Effect of magnetic treatment on irrigation water quality 2.2 Effect of magnetized water on soil properties 2.3 Effect of magnetized water on germination and growth 2.4 Effect of magnetized water on yield and quality parameters 2.5 Effect of magnetized water on physiological properties 2.1 Effect of magnetic treatment on water properties Joshi and Kamat (1981) hypothesized that magnetic treatment affects the nature of hydrogen bonds between water molecules. They reported changes in water properties such as light absorbance, surface tension and ph due to magnetic treatment. Lipus (1994) reported that the characteristic relaxation time of hydrogen bonds between water molecules is estimated to be much too fast and the applied magnetic field strengths were much too small for any such lasting effects. Based on these observations, they remarked that magnetic effects are unlikely to affect water molecules. According to Quinn et al. (1997) the polar molecules attain different orientation under the influence of a magnetic field. They concluded that stronger the magnetic field, greater the number of dipoles pointing in the direction of the field. Bogatin et al. (1999) showed that magnetizing the water increased the number of crystallization centers and free gas content. They opined that degassing of water increases permeability in soil, which results in an appreciable increase in irrigation efficiency. The application of magnetic fields on water decreased the hydration of salt ions and colloids and also showed a positive effect on salt solubility, accelerated coagulation and salt crystallization (Hilal and Hilal, 2000). Quickenden et al. (2002) found no ph change in double distilled water subjected to a very strong magnetic field of 24,000 Gauss. Cho and Lee (2005) studied the effects of magnetic treatment by a permanent magnet on surface tension of water. Two separate experiments were conducted. One was the measurement of surface tension and the other was a flow-visualization in water samples. Both experiments showed that as the number of treatments increased, the surface tension of the sample decreased. The application of a magnetic field on water increased the absolute viscosity of water when compared to control. Ghauri and Ansari (2006) attributed this to stronger hydrogen bonds formed. Otsuka and Ozeki (2006) observed no change in the properties of pure water due to magnetic treatment. However, the surface tension changed when the same magnetic treatment was carried out after the distilled water was exposed to O 2. Taia et al. (2007) found significant increase in the rate of water absorption by plants. He explained the results by the variations induced by magnetic fields in the ionic currents across the cellular membrane resulting in change in the osmotic pressure. Chang and Weng (2008) studied the structural changes induced in liquid water by the application of a magnetic field with a strength ranging from 1 to 10 tesla(t). They concluded that the

11 structure of the water was more stable and the ability of the water molecules to form hydrogen bond was enhanced by magnetic field. Feng and Deng (2008) studied the influence of magnetic field on microscopic structures and macroscopic properties of water. The results showed that the magnetic fields increased the soaking degree and hydrophobicity of water to materials, depressed its surface-tension, diminished the viscosity and increased the refraction index, dielectric constant and electric conductivity of water after magnetization. Tai et al. (2008) discovered that the crystal growth rates of calcite were suppressed completely in the presence of the magnetic field under low ph and supersaturating conditions. Alkhazan and Saddiq (2010) studied the effect of magnetic field on the physical, chemical and microbiological properties of the lake water in Saudi Arabia. They observed a relative increase in the ph value and a remarkable decrease in its odor and electric conductivity (EC), lead ions and bacterial content in lake water due to an increased magnetic flux density. Szcze s et al. (2010) studied the effects of static magnetic field on water at kinetic condition. Here, water was exposed for different times to weak static magnetic field (MF) generated from a single permanent magnet (B = 0.27T) at flow rate conditions. It was found that the MF increased the flow rate and there by increased the amount of evaporated water. They concluded that these effects are due to the hydrogen bond network strengthening and the perturbation of gas/liquid interface from the air nano bubbles in the water. Aoda and Fattah (2011) conducted a field experiment to study the influence of water magnetism under full and limited irrigation schemes on actual evapo-transpiration, growth and yield of corn. Three different irrigation treatments (100, 75 and 50%) were applied depending on soil water depletion replenishments. The results showed that the growth and productivity of corn were increased due to increased water use efficiency and irrigation water use efficiency when irrigation water was magnetized particularly under water deficit condition. Grewal and Maheshwari (2011) observed some changes in the physical and chemical properties of water due to magnetic treatment. The changes were observed mainly in hydrogen bonding, polarity, surface tension, conductivity, ph and solubility of salts which were reported to affect the growth of plants. They concluded that reduction in water ph and increase in EC in magnetic treated water may be due to changes in hydrogen bonding and increased mobility of ions. Musa and Hamoshi (2012) studied the effect of magnetic field on the solubility of sodium chloride and calcium chloride dihydrate at different temperature and ph values. A magnetic funnel with a magnetic field power of 450 gauss was used to prepare the magnetic water by passing 1, 5 and 10 times with flow rate of ml s -1. The increase in ph value was more effective as compared with elevation in temperature in increasing the electrical conductivity due to magnetic effect. Surendran et al. (2013) studied the impact of magnetic treatment of low quality irrigation water on the growth parameters of cow pea and on properties of water. In this work, hard water of 150, 300 ppm and saline water of 500, 1000 and 2000 ppm of both control and magnetic treated solutions were used. Two permanent magnets with the strength of gauss were used to magnetize the water. They reported a reduction in electrical conductivity, total dissolved salts and salinity levels of all solutions except normal irrigation water. An increase in ph was noticed for all the treatments. 2.2 Effect of magnetized water on soil properties Noran et al. (1996) studied the effect of irrigation with magnetically treated water on the translocation of minerals in the soil. They reported that the magnetic field interacts with the surface charges of particles in the fluid solutions, affecting the crystallization and precipitation of the solids. These processes are reported to effect the translocation of minerals in irrigated soil. The magnetic water treatment increased yield (10-15%), root formation, the transfer of phosphorus fertilizers into more soluble form and a decreased secondary salinification of soil (Bogatin et al., 1999). They also reported that magnetic treatment improved conditions of root layers due to (a) leaching of superfluous salts (b) better permeability of irrigated water and (c) better dissociation of mineral fertilizers. Hilal and Hilal (2000) reported that magnetic water increased leaching of excess soluble salts, lowered soil alkalinity and dissolved slightly soluble salts.

12 Selim (2008) conducted an experiment to evaluate the effectiveness of magnetizing underground brackish water to salt accumulation in soil and mobility of nutrient elements in root zone. They indicated that magnetized water induced changes in mobility of nutrient elements in root zone and also induced changes in solubility of some soil components such as CaCO 3 and gypsum. Fard et al. (2011) studied the effects of magnetized water on soil sulphate ions in trickle irrigation system. The results showed that at all soil depths below the emitter, the mean soil sulphate ions for the magnetized irrigation water were less than the non-magnetized irrigation water treatment. For the magnetized irrigation water treatment, soil sulphate ions decreased on average up to 37.3 per cent (p<0.01). Ashrafi et al. (2012) conducted an experiment to study the feasibility of using magnetic technology to reduce the dispersion of soil. In this study, three magnetic water devices with different magnetic intensities (0.05, 0.16 and 0.13 tesla) were used for magnetizing the potable water. The results showed that the magnetic field has a significant effect on magnesium and the calcium concentrations which were more in magnetic treatment compared to reference treatment. Mohamed (2013) conducted an experiment to evaluate the effect of magnetic treatments on tomato grown under saline irrigation conditions (Nile water, 1000, 3000, 6000, 9000 and ppm salts). The result showed a decrease in electrical conductivity of the soil due to magnetic saline water irrigation in sandy soil. Mohamed and Baseem (2013) conducted a column experiment to evaluate the effect of magnetic treated irrigation water on the movement and availability of certain nutrients and on the leaching of ions and salts from a sandy soil. They reported that total salt removal from the soil after six leachates and potassium concentration in soil water extract was significantly increased with magnetized water as compared to normal water. 2.3 Effect of magnetized water on germination and growth Kordas (1999) conducted a pot experiment (irrigated with normal water) to study the effect of a constant magnetic field on the root system and green tops of spring wheat. They observed a slight stimulating effect of magnetic treatment on growth of wheat. Growth dynamics were weakened, plants, culms, ears were shorter and structure of spring wheat crop was very small under magnetic untreated compared to magnetic treated pots. Atak (2008) reported that wheat plants irrigated with magnetized water exhibited marked increase in the most of vegetative growth parameters, chemical constituents i.e. photosynthetic pigments (chlorophyll a, chlorophyll b and carotenoids), total phenols and total indole over the control plants. Also exhibited an increase in the number of protein bands, yield components and yield compared with tap water treatment. Selim (2008) conducted an experiment to evaluate the effectiveness of magnetized underground brackish water on germination of test crops viz; wheat, barley and triticale. The magnetized irrigation water increased seed germination over control in all the crops. Amira et al. (2010) conducted two pot experiments to study the effect of irrigation with magnetized water on growth of lentil. They reported that lentil plants irrigated with magnetized water significantly increased plant height, fresh and dry weight per plant compared to tap water treatment. Grewal and Maheshwari (2011) conducted an experiment to study the effects of magnetic treatment of irrigation water on the emergence and early growth in snow pea and Kabuli chickpea. treated water led to a significant increase in emergence rate index (ERI; 42% for snow pea and 51% for chickpea), shoot dry weight (25 and 20 per cent for snow pea and chickpea, respectively) in both varieties compared to control. Yazied et al. (2012) studied the effects of magnetic bio-stimulation on tomato plants under NPK fertilizer levels. They reported that magnetic stimulated seeds or irrigation with magnetized water gave taller and heavier plants compared to control treatment and also concluded that magnetic treatments for both seeds and irrigation water under 75 or 100 per cent NPK of recommended levels gave the best results. Mohamed (2013) conducted an experiment to evaluate the effect of magnetic treatments on tomato grown under saline irrigation conditions (Nile water, 1000, 3000, 6000, 9000 and ppm). The results demonstrated that improvement in fresh and dry weights of tomato plant due to magnetic treatment compared to control.

13 Surendran et al. (2013) studied the impact of magnetic treatment of low quality irrigation water on the growth parameters of cow pea and on properties of water. In this work, hard water of 150, 300 ppm and saline water of 500, 1000 and 2000 ppm of both control and magnet treated solutions ( gauss) were used. They reported a significant increase in growth parameters such as stem and root length in magnet treated solutions than in control solutions. 2.4 Effect of magnetized water on yield and quality parameters Carbonell et al. (2003) reported that irrigation of signal- grass seeds with magnetically treated water (40 mt) for 10 to 180 minutes increased the percentage and rate of germination close to 10% for all the magnetic treatments and treatment of water for 60 min increased germination by about 18 per cent related to control. Nasher (2008) observed the influence of magnetized water on chickpea seed growth, where the lengths of the seedlings irrigated with magnetized water were taller than seeds irrigated with tap water. The difference in length was 2.67 cm between them after 18 days of sowing. Selim (2008) conducted an experiment to evaluate the effectiveness of magnetized underground brackish water on germination of test crops viz., wheat, barley and triticale. The result indicated that magnetized irrigation water increased seed germination, full seed germination of 100 per cent for wheat, barley and triticale after 6 days from sowing compared to a rate of 83, 86 and 86 per cent after 9 days from sowing for magnetic untreated water, respectively. Grewal and Maheshwari (2009) studied the effect of magnetic treatment of irrigation water types on crop yield and water productivity of snow pea and celery plants. They reported that magnetic treatment of recycled water and 3000 ppm saline water increased celery yield by 12 and 23 per cent and water productivity by 12 and 24 per cent. For snow pea, the per cent increases were 7.8, 5.9 and 6.0 in pod yield and 12, 7.5, 13.0 in water productivity respectively for magnetically treated potable water, recycled water and 1000 ppm saline water. Amira and Qodas (2010) conducted two pot culture experiments to study the effect of irrigation with magnetized water on yield of flax. Increase in seed yield per plant reached to 9.10 per cent compared with tap water treatment. Hozayn and Qados (2010) studied the response of some food crops (wheat, flax, chick pea and lentil) using magnetized water for irrigation under green house condition. The magnetized water treatment increased yield and yield component traits of all crops. The increases in seed yield per plant reached to and per cent for flax and wheat, respectively and reached to and per cent for lentil and chick-pea, respectively compared with crops irrigated with tap water. Hozayn and Amany (2011) experimented on the influence of magnetized water on wheat, flax, chick pea and lentil plants. The magnetic treatment increased yield and yield component traits of all crops. The increase in seed yield per plant reached to 9.10, 31.33, and per cent for flax, wheat, lentil and chickpea respectively compare to control. Yazied et al. (2012) studied the effects of magnetic bio-stimulation on tomato plants under NPK fertilizer levels. They reported that magnetic stimulated seeds or irrigation with magnetized water increased total yield compared to control treatment and also concluded that magnetic treatments for both seeds and irrigation water under 75 or 100 per cent NPK of recommended levels gave the best results. Surendran et al. (2013) studied the impact of magnetic treatment of low quality irrigation water on the growth parameters of cow pea and on properties of water. The hard water of 150, 300 ppm and saline water of 500, 1000 and 2000 ppm of both control and magnet treated solutions ( gauss) were used. The magnetic treatment of irrigation water types improved germination per cent of cow pea which ranged from 7.1 to per cent compared to control solutions. 2.5 Effect of magnetized water on physiological properties Atak (2008) reported that wheat plants irrigated with magnetized water exhibited marked increase in the most of chemical constituent i.e. photosynthetic pigments (chlorophyll a, chlorophyll b and carotenoids), total phenols and total iodole over the control plants. Also exhibited an increase in the number of protein bands, yield and yield component at harvest and grain, straw content compared with tap water treatment.

14 Amira et al. (2010) conducted two pot culture experiments to study the effect of irrigation with magnetized water on some chemical constituents of lentil. Chlorophyll contents (chl a, chl b and chl a+b), carotenoids, total pigments, total phenol and total indole content increased to 13.58, 44.67, 21.4, 2.7, 21.4, 20 and per cent, respectively compared to tap water treatment. Hozayn and Qados (2010) studied the response of some food crops (wheat, flax, chick pea and lentil) using magnetized water for irrigation under green house condition. They opined that magnetic treatment could involve in the activation of phyto hormone such as gibberellic acidequivalents, indole-3 acetic acid and trans-zeatin as well as activation of the bio-enzyme systems which leads to the growth improvement and increase the crop yield. According to Alkhazan and Saddiq (2010) magnetically treated water significantly enhanced photosynthetic pigment, water holding capacity, the essential element except sodium in plants. Hozayn and Amany (2011) studied the response of some food crops (wheat, flax, chick pea and lentil) using magnetized water for irrigation purpose under green house condition. They revealed that the plants which were irrigated with magnetic water exhibited a remarkable increase in biochemical constitution and the number of protein bands when compared to untreated control plants. Moussa (2011) studied the response of common bean irrigated with magnetized tap water and monitored its chemical constituents. The magnetic treatment induced significant increase in GA 3, kinetin, nucleic acids (RNA and DNA), photosynthetic pigments (chlorophyll a, chlorophyll b and carotenoids), photosynthetic activity (CO 2 -fixation) and translocation efficiency of photo assimilates (CO 2 -assimilation) as compared with control plants.

15 MATERIAL AND METHODS Laboratory and pot culture experiments were conducted at College of Agriculture, Dharwad during to study the effect of magnetized water on irrigation water quality, soil properties and crop growth. The details of the materials used and the techniques adopted in the study are explained in this chapter. 3.1 Preparation of saline irrigation waters Irrigation waters with natural chemical composition are preferred over artificially synthesized ones in experiments involving micro plots or pot culture. In this study, irrigation waters of desired salinity were prepared by using natural saline soil. Large quantity of a highly saline soil was collected from farmer s field at Shankratti village, Athani taluk, Belagavi district. Karnataka. The soil was mixed with demineralised water in the ratio of 1:3, stirred vigorously and kept overnight. The supernatant saline water was filtered to remove suspended materials and stored in closed containers. This saline water with 32 ds m -1 was diluted appropriately with demineralised water to get desired salinity levels of irrigation waters 2, 4, 6, 8, 12 and 16 ds m -1 (to correspond with 2 EC, 4 EC, 6 EC, 8 EC, 12 EC and 16 EC). Under first objective, to study the effect of magnetic treatment on water quality, the samples with distinct salinity levels of 4, 8, 12 and 16 ds m -1 were used along with good water (GW, 0.6 ds m - 1 ) as control. Under second objective, while studying the effect of magnetized water on soil properties, GW (0.6 EC), 2, 4, 6 and 8 EC waters were used as the crop cannot grow beyond this limit. Under third objective to study the effect of magnetized water on leaching efficiency of saline soil, the irrigation water with marginal salinity i.e., 2 ds m -1 (2 EC) was used. To achieve fourth objective where crop was involved (sunflower), irrigation waters with GW, 2 EC, 4 EC, 6 EC and 8 EC were used. 3.2 Magnetization of irrigation water A permanent magnet with magnetic strength of 1200 gauss was used in this study for magnetizing irrigation waters. The set up of the unit for the magnetic treatment of irrigation water is shown in Plate 1. A PVC beaker of 2 litre capacity fitted at the top of the unit served as the storage tank for the untreated water. Water from the bottom of this tank enters the magnetic device. The device comprised of a 100 mm pipe section with its internal diameter 20 mm. The device contained two magnets and the arrangement of their north and south poles and the direction of magnetic field generated are shown in Fig. 1. For the magnetic treatment of irrigation water, it was passed through the magnetic treatment device at the flow rate of 12 ml s -1, providing the water a magnetic field exposure of about 6 s. Fig. 1. Schematic diagram of magnetic fields and direction of water flow during the magnetic treatment 3.3 Methodology for first objective Four sets of irrigation water samples consisting of GW (0.6 EC), 4, 8, 12 and 16 EC were used. The experiment was laid in CRD with two factors (salinity and magnetic treatment) with four replications. One set was not magnetically treated (magnetically untreated) while other three sets were subjected to magnetic treatment. Prior to characterizations, 2 nd, 3 rd and 4 th sets of samples were magnetized by passing once, twice and thrice, respectively through the magnetic device. The characterization was done in respect of major irrigation water quality parameters like ph, EC, SAR and RSC.

16 Plate 1. The magnetic device used to magnetize irrigation waters Plate 2. A view of column studies

17 3.4 Methodology for second objective The PVC columns of 20 cm height and 7 cm diameter with bottom covered by end caps having 2 mm perforations to facilitate drainage were used to treat the soil. The normal (non-saline) black soil was collected from the field of Main Agricultural Research Station, Dharwad. The soil was texturally clay, neutral in ph (7.25), non- saline (0.6 ds m -1 ), medium in organic carbon (6.5 gm/kg) with CEC of cmol (p+) kg -1 soil. The sample was dried, ground and sieved through 2 mm sieve and used for filling in the columns. Each PVC column was filled with 850 gm of soil. The soil was filled in four parts. After filling each part (¼), the column was tapped against a hard surface and the soil within the column was compacted with a suitable wooden hammer to ensure natural compaction of the soil, to the extent possible. One set of columns was first saturated with one pore volume (340 ml) of different salinity waters (GW, 2, 4, 6, 8 EC) and later passed with another two pore volumes of magnetic untreated respective waters. After passing all the three pore volumes of water, the column was left for drying, sample was taken out, processed and analyzed for ph, EC e exchangeable cations (Ca, Mg and Na) and water soluble ions (Ca and Mg), exchangeable sodium percentage and clay dispersion. Similarly, another set was passed with five pore volumes of different salinity waters and the soil was characterized. The experiment was repeated on fresh columns by passing magnetic treated irrigation waters (three times passed) through the columns. The chemical characteristics of soils after passing three and five pore volumes of magnetic untreated and treated irrigation waters were evaluated. The experimental design followed and replications had were same as detailed in section Methodology for third objective To investigate the effect of magnetized irrigation water on leaching efficiency of salts, again a column experiment was carried out. The experiment was laid in RCBD with four replications. Instead of using normal soil, saline soil having a salinity of 7.2 ds m -1 was used. Soil samples were collected from Shankarhatti, Athani Taluk, Belagavi district. The collected soil samples were air dried, ground to pass through 2.0 mm sieve and thoroughly mixed. The PVC columns were packed with 500 gm saline soil. The packing procedure remained same as detailed under earlier column study. The soil columns filled with saline soil were leached with 1, 2, 3, 4 and 5 pore volumes of marginal saline water; both magnetically untreated and treated (three times passed). Separate sets of columns were maintained for passing 1, 2, 3, 4 and 5 pore volumes of water. For example, in case of set one, one pore volume of water (200 ml) was passed through the columns (triplicate) and salinity of the leachate and salinity of the soil after leaching was estimated. In case of three pore volume treatment, first, one pore volume of water was passed; leachate was collected and analyzed for its salinity. Then second pore volume of water was passed and again leachate was collected and analyzed. Similarly, the process was repeated after passing third pore volume of water. After passing all the three pore volume of water, the soil samples were processed and analyzed for their salinity (EC 2.5, ds m -1 ). Using the soil salinity data, the leached fraction under different treatments including both magnetically untreated and treated were calculated. 3.6 Methodology for fourth objective Green house experiment was conducted to examine the effect of magnetized water on germination and early growth of sunflower. The experimental design followed and replications had were same as detailed in section 3.3. Irrigation waters with salinity levels of 0.6, 2, 4, 6 and 8 EC (both non-magnetized and magnetized) were used in this study. Three times passed magnetized water was used in this study. Polythene covers (height of 25cm) filled with 1.25 kg of normal soil was used to grow sunflower. Five seeds were sown in each pot. The germination count was recorded 5 days after sowing (5 DAS). Then, plants were thinned and only two healthy ones were retained and grown up to 45 days. On 45 th day, the plant height was recorded, the plants were uprooted, dried for constant weight, recorded the dry matter yield and further analyzed for Na and K contents.

18 3.7 Analysis of irrigation water quality ph of water The ph of water was determined using ph meter (Sparks, 1996) Electrical conductivity (ds m -1 ) Electrical conductivity of the water was determined by using Systronics direct digital conductivity meter 304 (Sparks, 1996) Water soluble cations and anions (me L -1 ) Calcium+ magnesium and calcium were estimated by versanate titration using Eriochrome Black-T and mureoxide indicators, respectively (Sparks, 1996). Sodium was estimated using flame photometer (Sparks, 1996). Carbonates and bicarbonates of water were estimated by titrating against standard H 2 SO 4 using phenolphthalein and methyl orange indicators, respectively (Jackson, 1967) Sodium adsorption ratio (SAR) The sodium adsorption ratio was calculated from Na +, Ca 2+ and Mg 2+ (me L -1 ) contents of water samples by using the following equation (Tandon, 1998) Residual sodium carbonate (RSC, me L -1 ) The residual sodium carbonate was calculated from CO 3 2-, HCO 3 -, Ca 2+ and Mg 2+ (me L -1 ) contents of water samples by using the following equation (Tandon, 1998): 3.8 Soil analysis Physical properties Maximum water holding capacity RSC = (CO 3 + HCO 3 ) (Ca + Mg) The maximum water holding capacity was determined using Keen s cup as described by Piper (1966) Chemical properties Soil ph The ph of soil was determined in 1: 2.5 soils to water suspension after stirring the samples intermittently for half an hour (Sparks, 1996) using a Systronics direct digital 331 ph meter Electrical conductivity (ds m -1 ) Electrical conductivity of the soil was determined in the supernatant of 1:2.5 soil to water suspension that was used for the ph determination (Sparks, 1996) by using Systronics direct digital conductivity meter Exchangeable cations (me 100 g -1 soil) Exchangeable calcium and magnesium in soil were determined in neutral normal ammonium acetate extract by Versanate titration as described by Sparks (1996). Exchangeable sodium was determined using flame photometer (Sparks, 1996) Water soluble cations and anions Calcium+ magnesium and calcium were estimated by versanate titration using Eriochrome Black-T and mureoxide indicators, respectively (Sparks, 1996).

19 Sodium was estimated using flame photometer (Sparks, 1996) Cation exchange capacity of soil (CEC, cmol (p+) kg -1 ) The cation exchange capacity of soil was calculated by using exchangeable calcium, magnesium and sodium values. Summation of all these three values was represented as cation exchange capacity of soil Exchangeable sodium percentage (ESP) The exchangeable sodium percentage was calculated from the exchangeable sodium (me 100 g -1 soil) and CEC (me 100 g -1 soil) by using following equation (Sparks, 1996): Exchangeable sodium ESP = CEC Clay dispersion The clay dispersion was done by using water dispersible clay technique. The procedure followed for clay dispersion was described below. Soil sample weighing 12.5 g was taken in a 250 ml conical flask and added with 25 ml distilled water and then kept for shaking in a mechanical shaker for 30 minutes. After 30 minutes, the soil sample was transferred to a 250 ml measuring cylinder and the volume was made up to 250 ml with distilled water and kept for settling of silt particles (4 hours). After 4 hours, 12.5 ml of suspension was pipetted and transferred to a china dish. It was kept in oven and dried at 110 o C for 8 hours. The weight of clay contained in 12.5 ml of soil water suspension was recorded and the percentage clay was calculated as under (Budihal, 1992): Amount of clay dispersed Water dispersible clay (%) = Weight of soil taken 3.9 Growth parameters of sunflower Germination percentage The germination percentage was calculated at 5 days after sowing (DAS) Plant height The plant height was measured from the base of the plant to the growing tip and the mean of two plants was taken in each pot at 30 and 45 DAS and expressed in centimeter Dry matter accumulation Two plants were selected from each polythene bag and were dried at 65 to 70 0 C in a hot air oven to attain constant weight. The oven dry weight was recorded and expressed in grams per plant Plant analysis Collection and preparation of plant samples Plant samples (whole plant) were collected from each polythene bag, air dried and then dried in hot-air oven at 60 C for 2 hours. The samples were ground in mixer. The powered plant samples were used for the analysis of Na and K contents Estimation of sodium and potassium in plant samples The di-acid extract prepared by digesting finely ground plant samples with HNO 3 and HClO 4 in the ratio of 9: 4 (Tandon, 1998) was used for estimation of sodium and potassium (K) by Flame photometry as outlined by Tandon (1998) and expressed in percentage Statistical analysis The experimental data statistically analyzed as per Gomez and Gomez (1984). The computed data was interpreted with a critical differences level at 5 per cent.

20 EXPERIMENTAL RESULTS An experiment was conducted to study the effect of magnetic treatment on irrigation water quality and in turn the influence of magnetized water on soil properties at large and leaching efficiency of salts and growth of sunflower crop, in particular. The results of the experiment are presented under different heads. 4.1 Effect of magnetic treatment on irrigation water quality 4.2 Effect of magnetized water on soil properties 4.3 Effect of magnetized water on leaching efficiency of salts 4.4 Effect of magnetized water on germination and early growth of sunflower 4.1 Effect of magnetic treatment on irrigation water quality Irrigation water quality was assessed mainly by ph, soluble salt content (EC), sodium adsorption ratio (SAR) and residual sodium carbonate (RSC). The effects of magnetic treatment on these properties are presented below ph The results on the effect of magnetic treatment and irrigation water salinity on ph of irrigation waters are presented in Table 1. When irrigation waters were passed once through the magnetic device (one time passed), the mean ph decreased significantly to 7.50 than ph of magnetic untreated water (7.56). When the same water was passed two times and three times through the magnetic device, the ph increased significantly to 7.57 and 7.56, respectively but remained on par with the ph of magnetic untreated water. However, the trend was different at different salinity levels of water. At lower salinity level (0.6 and 4 EC), multiple magnetic exposures had no significant effect on ph over one time passed water. But, at higher salinities (12 and 16 EC), multiple magnetic exposures resulted in significant increase in the ph over one time passed water. In case of magnetic untreated water, the ph increased significantly as EC iw increased from 0.6 to 8 ds m -1 (7.41, 7.74 and 7.97 at 0.6, 4 and 8 ds m -1, respectively) but decreased significantly at 12 ds m -1 (6.99). Similar trend was observed with mean ph of magnetic treated waters also. The mean ph of magnetic treated waters increased significantly as EC iw increased from 0.6 to 8 ds m -1 (7.20, 7.70 and 8.03 at 0.6, 4 and 8 ds m -1, respectively) but decreased significantly at 12 ds m -1 (7.06) Electrical conductivity The data on the effect of magnetic treatment on electrical conductivity (ds m -1 ) of irrigation waters is presented in Table 2. The magnetic treatment of irrigation waters significantly decreased the electrical conductivity. The mean salinity of magnetic untreated irrigation waters irrespective of their salinity was 8.12 ds m -1 which decreased significantly to 7.97 (one time passed), 8.03 (two times passed) and 8.07 (three times passed) due to exposure to magnetic field. The multiple exposures, however, resulted in an increase in the electrical conductivity. The electrical conductivity values were 7.97, 8.03 and 8.07 for one time passed, two times passed and three times passed, respectively. Similar trend was observed between magnetic treated and untreated irrigation waters with varied salinity levels. The reduction in salinity was more conspicuous at the lower level of salinity and with one time passed water Calcium The data on the effect of magnetic treatment and irrigation water salinity on calcium content (me L -1 ) of irrigation waters is presented in Table 3. The calcium content of the water was significantly influenced by magnetic treatments and salinity levels. Irrespective of salinity levels, significantly higher calcium content were recorded in magnetic untreated water (16.18me L -1 ) compared to mean calcium content in magnetic treated water (15.76me L -1 ).

21 Among magnetic treatments, irrespective of salinity of water, passing water either once or twice or thrice through the magnetic device resulted in significantly higher reduction in calcium content compared to magnetic untreated water. The reduction was most conspicuous with one time passed water than with other two. Similar trend was observed with all saline waters. Calcium concentration increased with increase in salinity levels in both magnetic treated and untreated. The higher calcium content was recorded with salinity level of 16 EC i.e me L -1 and 31.90me L -1 in both magnetic untreated and treated water, respectively and lowest was recorded with magnetically three times treated 0.6 EC water (0.59me L -1 ) Magnesium The data on the effect of magnetic treatment and irrigation water salinity on magnesium content (me L -1 ) of irrigation waters is presented in Table 4. Magnesium content of water was found to vary significantly due to both magnetic treatment and salinity levels in irrigation water. Irrespective of salinity levels, magnetic untreated water recorded significantly higher mean magnesium content (11.71me L -1 ) compared to mean magnesium content of magnetic treated water (11.45me L -1 ). Among magnetic treated waters, passing water once through the magnetic device, significantly reduced magnesium content over magnetic untreated water. With subsequent multiple magnetic treatments (two and three times passed), magnesium content though increased numerically the differences remained non-significant. Magnesium content increased in both magnetic untreated and treated water with increase in salinity levels of irrigation water. Both magnetic untreated and treated waters recorded highest magnesium concentration under 16 EC irrigation water i.e and 23.00me L -1, respectively Sodium The data on the effect of magnetic treatment and irrigation water salinity on sodium content (me L -1 ) of irrigation waters is presented in Table 5. The sodium content of the water was significantly influenced by magnetic treatments and irrigation water salinity. untreated water, across salinity levels, recorded higher mean sodium content (62.83me L -1 ) compared to mean sodium content of magnetic treated water (48.12me L -1 ). treated one time passed water (40.85me L -1 ) was significantly superior over two times (48.12me L -1 ) and three times passed water (55.39me L -1 ). Among magnetic treated waters, passing water once through the magnetic device significantly reduced sodium content (40.85me L -1 ) over magnetic untreated water (62.83me L -1 ). With subsequent multiple magnetic treatments (two and three times passed), sodium content increased significantly but remained lower than sodium content in magnetic untreated water. With increase in salinity levels, sodium content increased in both magnetic untreated and treated waters. Either treated magnetically or not, the highest sodium contents were recorded in 16 ds m -1 EC while lowest in 0.6 ds m -1 EC water Sodium adsorption ratio (SAR) The data on the effect of magnetic treatment and irrigation water salinity on sodium adsorption ratio of irrigation waters is presented in Table 6. The SAR of water was significantly influenced by magnetic treatments. The higher SAR was recorded in magnetic untreated water (15.68me L -1 ) compared to magnetic treated water (12.32me L - 1). The SAR of water significantly decreased when exposed once to the magnetic field. However, multiple magnetic exposures (two times and three times passed) resulted in significant increase in SAR but, remained significantly lower than magnetic untreated water. Irrespective of magnetic treatment, SAR values increased as salinity of water increased recording significantly higher values with 16 ds m -1 EC water. untreated 16 EC water recorded the highest SAR of me L -1. The interaction effects between magnetic treatments and salinity levels were found non- significant.

22 Table 1. Effect of magnetic treatment and salinity levels on ph of irrigation waters ECiw (ds m -1 ) untreated One time passed ph treated Two times passed Three times passed Mean 0.6 (GW) Mean treatment (M) Salinity levels (S) M x S SEm.± CD (P=0.05) NS EC iw = Electrical conductivity of irrigation water Table 2. Effect of magnetic treatment on Electrical conductivity of irrigation waters ECiw (ds m -1 ) untreated One time passed EC (ds m -1 ) treated Two times passed Three times passed Mean 0.6 (GW) Mean treatment (M) Salinity levels (S) M x S SEm.± CD (P=0.05) NS

23 Table 3. Effect of magnetic treatment and salinity levels on calcium content of irrigation waters ECiw (ds m -1 ) untreated One time passed Calcium (me L -1 ) treated Two times passed Three times passed Mean 0.6 (GW) Mean treatment (M) Salinity levels (S) M x S SEm.± CD (P=0.05) NS Table 4. Effect of magnetic treatment and salinity levels on magnesium content of irrigation waters ECiw (ds m -1 ) untreated One time passed Magnesium (me L -1 ) treated Two times passed Three times passed Mean 0.6 (GW) Mean treatment (M) Salinity levels (S) M x S SEm.± CD (P=0.05) NS

24 Table 5. Effect of magnetic treatment and salinity levels on sodium content of irrigation waters ECiw (ds m -1 ) untreated One time passed Sodium (me L -1 ) treated Two times passed Three times passed Mean 0.6 (GW) Mean treatment (M) Salinity levels (S) M x S SEm.± CD (P=0.05) NS Table 6. Effect of magnetic treatment and salinity levels on sodium adsorption ratio of irrigation waters ECiw (ds m -1 ) untreated Sodium adsorption ratio (me L -1 ) One time passed treated Two times passed Three times passed Mean 0.6 (GW) Mean treatment (M) Salinity levels (S) M x S SEm.± CD (P=0.05) NS

25 4.1.7 Carbonate and bicarbonates Carbonate was absent in irrigation water. The data on the effect of magnetic treatment and irrigation water salinity on bicarbonate content (me L -1 ) of irrigation waters is presented in Table 7. The bicarbonate concentration of water was significantly influenced by magnetic treatments and salinity levels of waters. untreated water recorded highest mean bicarbonate content (1.57me L -1 ) compared to mean value for magnetic treated water (1.44me L -1 ) across salinity levels. The one time passed magnetized water showed significantly lower mean bicarbonate contents (1.36me L -1 ) compared to magnetic untreated water (1.57me L -1 ). With increased frequency of magnetization (two times and three times passed), a significant increase in bicarbonate content was observed. The bicarbonate contents of three times magnetic treated water almost equaled the initial bicarbonate content before magnetization. With respect to different saline waters, except few cases, either magnetic treated or untreated, the bicarbonate contents significantly increased with increase in water salinity. Lowest bicarbonate contents were recorded in 0.6 EC (1.29, 1.23, 1.25 and 1.27me L -1 in magnetic untreated, magnetic passed- one time, two times and three times, respectively) which increased significantly at 16 EC (1.81, 1.47, 1.53 and 1.80 me L -1 in magnetic untreated, magnetic passed- one time passed, two times passed and three times passed water, respectively) Residual sodium carbonate (RSC) The data on the effect of magnetic treatment and irrigation water salinity on residual sodium carbonate (me L -1 ) of irrigation waters is presented in Table 8. The RSC of water was significantly influenced by magnetic treatments and salinity levels of irrigation waters. treated water recorded significantly higher mean RSC value (-25.76me L -1 ) compared to magnetic untreated water (-26.32me L -1 ). The mean RSC value decreased significantly from one time (-25.55me L -1 ) to two times magnetic treatment (-25.84) however, did not change much with third time magnetic exposure (-25.90me L -1 ). Similar trend was observed irrespective of salinity of water. The residual sodium carbonate content decreased significantly with increase in salinity of water, irrespective of magnetic treatment. The interaction between magnetic treatments and salinity levels remained non-significant Chloride The data on the effect of magnetic treatment and irrigation water salinity on chloride content (me l -1 ) of irrigation waters is presented in Table 9. The mean contents of chloride across salinity levels under magnetic untreated (42.06me L -1 ) and treated (41.66me L -1 ) waters did not differ significantly. However, irrespective of magnetic treatments, chloride contents increased significantly with increase in salinity of water. Highest chloride contents were recorded in 16 EC waters, either direct or passed through magnetic device (81.37, 80.74, and 80.57me L -1 in magnetic untreated, magnetic- one time passed, two times passed and three times passed water, respectively). The effect of multiple exposures of waters to magnetic effect revealed that two times (41.72me L -1 ) and three times (41.44me L -1 ) magnetic treated waters showed significantly lower mean chloride contents than magnetic untreated water (42.06 me L -1 ). Almost similar trend was observed in different saline waters. Passing different saline waters once through the magnetic device had no effect on chloride contents. The ph, EC, Ca 2+, Mg 2+, Na +, Cl - and HCO 3 - contents were decreased in magnetic treated as compared to magnetic untreated waters. 4.2 Effect of magnetized water on soil properties Soil reaction (ph) The data on the effect of magnetic treatment and saline water irrigation on soil ph is presented in Table 10. The soil ph was significantly influenced by magnetic treatments as well as salinity levels of waters. The soil samples which received three and five pore volumes magnetized water recorded

26 lower ph (7.48 and 7.62) compared to soil samples which received non-magnetized water (7.85 and 7.91, respectively). Irrespective of magnetically treated or untreated, soil ph decreased significantly with increase in the salinity of water applied, either three or five pore volumes. The mean ph values were significantly higher (7.77) with the application of more water (five pore volumes) compared to three pore volume water application (7.67). Interaction of magnetic treatment and salinity levels were significantly influenced by each other. Among the salinity levels, soil which received magnetic untreated 0.6 EC water recorded higher ph value of 8.23 and 8.29 with three and five pore volumes, respectively. Significantly lower ph was recorded in soil which received magnetic treated 8 EC water (7.35 and 7.39 in 3 and 5 pore volumes, respectively) Electrical conductivity (ds m -1 ) The data on the effect of magnetic treatment and saline water irrigation on soil salinity (ds m - 1 ) is presented in Table 11. The EC of the soil samples was significantly influenced by magnetic treatments as well as salinity levels at both water application rates. Highest EC values (0.39 and 1.75 ds m -1 ) were recorded in soils which received magnetic treated water while, the lowest EC values (0.26 and 1.09 ds m -1 ) were recorded in soils irrigated (passed) with magnetic untreated water in both three and five pore volumes, respectively. Soil salinity increased due to increased salinity level of water applied under both magnetic treated and magnetic untreated water treatments. Soil which received 8 EC water recorded higher EC value in both 3 pore volumes (0.72 and 0.43 ds m -1 in magnetic treated and untreated waters, respectively) and 5 pore volumes (3.83 and 2.67 ds m -1 in magnetic treated and untreated waters, respectively). The 5 pore volumes recorded highest EC value compared to 3 pore volumes in both magnetic treated and untreated water. The interaction between salinity and magnetic treatment remained significant. Passing 8 EC magnetic treated water recorded highest electrical conductivity values (0.72 and 3.83) in both 3 and 5 pore volumes, respectively Exchangeable calcium The data on the effect of magnetic treatment and saline water irrigation on exchangeable calcium (me 100 g -1 soil) is presented in Table 12. Significant effect of magnetic treatments was noticed with respect to calcium content. untreated soil recorded highest mean calcium contents (43.90 and me 100 g -1 soil, respectively in 3 and 5 pore volumes) and lowest values were (36.96 and me 100 g -1 soil in 3 and 5 pore volumes, respectively) recorded in magnetic treated soil. Similar trend was observed with passing of 0.6, 2, 4, 6 and 8 EC water. Irrespective of magnetic treatment and salinity of water, passing of 5 pore volumes recorded significantly higher exchangeable calcium ( me 100 g -1 soil) compared to 3 pore volumes ( me 100 g -1 soil). Among the salinity levels, soil passed with 5 pore volumes of magnetic treated and untreated 8 EC water recorded significantly higher calcium content (42.89 and me 100 g -1 soil, respectively) compared to 3 pore volumes of magnetic treated and untreated 8 EC water (40.65 and me 100 g -1 soils, respectively). The interaction between salinity and magnetic treatment remained significant. Passing 8 EC magnetic untreated water recorded highest electrical conductivity values (47.47 and 48.03) in both 3 and 5 pore volumes, respectively Exchangeable magnesium Results on the effect of magnetic treatment and saline water application on exchangeable magnesium (me 100 g -1 soil) is presented in Table 13. Unlike exchangeable calcium, exchangeable magnesium significantly increased due to magnetic treatment. Soils applied with magnetized three and five pore volumes of saline waters recorded mean exchangeable magnesium of and me 100 g -1 soil, respectively compared to non-magnetized waters (4.88 and g -1 soil, respectively with three and five pore volumes, respectively). The exchangeable magnesium in soil also significantly increased due to application of waters with increased salinity load with either three or five pore volumes of water. The magnetic effect increasing exchangeable magnesium was of higher magnitude with three pore volume water applications than five pore volume. The interaction between salinity and magnetic treatment remained significant. Passing 8 EC magnetic treated water recorded highest exchangeable magnesium values (12.22 and 12.94) in both 3 and 5 pore volumes, respectively.

27 Table 7. Effect of magnetic treatment and salinity levels on bicarbonate content of irrigation waters ECiw (ds m -1 ) untreated One time passed Bicarbonate (me L -1 ) treated Two times passed Three times passed Mean 0.6 (GW) Mean treatment (M) Salinity levels (S) M x S SEm.± CD (P=0.05) NS Table 8. Effect of magnetic treatment and salinity levels on residual sodium carbonate of irrigation waters ECiw (ds m -1 ) untreated Residual sodium carbonate (me L -1 ) One time passed treated Two times passed Three times passed Mean 0.6 (GW) Mean treatment (M) Salinity levels (S) M x S SEm.± CD (P=0.05) NS

28 Table 9. Effect of magnetic treatment and salinity levels on chloride content of irrigation waters Chloride (me L -1 ) ECiw (ds m -1 ) untreated One time passed treated Two times passed Three times passed Mean 0.6 (GW) Mean treatment (M) Salinity levels (S) M x S SEm.± CD (P=0.05) NS Table 10. Effect of magnetized waters of variable salinity on soil ph ph ECiw (ds m -1 ) untreated Three pore volumes treated Mean untreated Five pore volumes treated Mean 0.6 (GW) Mean treatment (M) Salinity levels (S) M x S treatment (M) Salinity levels (S) M x S SEm.± CD(P=0.05)

29 Table 11. Effect of magnetized water on Electrical conductivity of soils ECiw (ds m -1 ) untreated Three pore volumes treated EC 2.5, ( ds m -1 ) Mean untreated Five pore volumes treated Mean 0.6 (GW) Mean treatment (M) Salinity levels (S) M x S treatment (M) Salinity levels (S) M x S SEm.± CD (P=0.05) Table 12. Effect of magnetized water on exchangeable calcium ECiw (ds m -1 ) untreated Exchangeable calcium (me 100 g -1 soil) Three pore volumes treated Mean untreated Five pore volumes treated Mean 0.6 (GW) Mean treatment (M) Salinity levels (S) M x S treatment (M) Salinity levels (S) M x S SEm.± CD (P=0.05)

30 4.2.5 Exchangeable sodium The data on the effect of magnetic treatment and saline water irrigation on exchangeable sodium (me 100 g -1 soil) is presented in Table 14. Significant effect of magnetic treatments was noticed with respect to mean sodium content between magnetic untreated and treated waters at both three and five pore volumes applications. The soil which received magnetic untreated water recorded highest sodium concentration (0.74 and 1.08 me 100 g -1 soil) which decreased due to magnetic treatment (0.56 and 0.89 me 100 g -1 soil) with passing of 3 and 5 pore volumes, respectively. Irrespective of salinity of water, significantly higher mean exchangeable sodium was recorded under 5 pore volume water application (0.98 me 100 g -1 soil) compared to three pore volume application (0.65 me 100 g -1 soil). With the application of either three or five pore volumes of direct or magnetized saline waters, the exchangeable sodium content increased. However, the increase was of higher magnitude with five pore volume application compared to three pore volume applications. The interaction between salinity and magnetic treatment remained significant. Passing 8 EC magnetic untreated water recorded highest exchangeable sodium values (1.39 and 1.95) in both 3 and 5 pore volumes, respectively Exchangeable sodium percentage The data on the effect of magnetic treatment and saline water application on exchangeable sodium percentage is presented in Table 15. The ESP of the soil samples was significantly influenced by magnetic treatments. Highest ESP was recorded in magnetic untreated soil i.e and 1.98 per cent compared to magnetic treated soil (1.01 and 1.62 per cent) in both 3 and 5 pore volumes, respectively. ESP value increased with increase in salinity levels. Compared to 3 pore volumes, highest ESP was recorded in 5 pore volumes (1.98 and 1.62 per cent) in both magnetic untreated and treated soil, respectively. Among the salinity levels, lowest ESP was observed in 0.6 EC water irrigated soil i.e and 0.19 per cent in 3 pore volumes and 3.66 and 1.83 per cent in 5 pore volumes, in magnetic untreated and treated waters, respectively. Highest ESP was observed in 8 EC water irrigated soil i.e and 3.58 per cent in magnetic untreated and 1.59 and 3.18 per cent in magnetic treated soil in both 3 and 5 pore volumes, respectively. The interaction between salinity and magnetic treatment remained significant. Passing 8 EC magnetic untreated water recorded highest ESP values (2.54 and 3.58) in both 3 and 5 pore volumes, respectively Water soluble calcium The data on the effect of magnetic treatment and saline water application on water soluble calcium (me L -1 ) is presented in Table 16. Significant effect of magnetic treatments was observed on water soluble calcium content. Highest water soluble calcium was recorded under non-magnetized water application (0.77 and 1.01me L -1 ) compared to magnetized water application (0.73 and 0.94me L -1 ) in both 3 and 5 pore volumes, respectively. As the salinity levels increased, there was an increase in water soluble calcium irrespective of magnetic treatment and water application rate. Application of magnetic treated 3 pore volumes of 0.6 EC water (0.56me L -1, respectively) was on par with magnetic untreated water (0.57me L -1 ) in respect of water soluble calcium. But, application of magnetized higher salinity waters decreased water soluble calcium significantly. Irrespective of magnetic treatment and salinity of irrigation waters, significantly higher water soluble calcium was recorded with five pore volume water applications over three pore volumes. The interaction between salinity and magnetic treatment remained significant. Passing 8 EC magnetic untreated water recorded highest water soluble calcium values (1.32) 5 pore volumes, respectively Water soluble magnesium The results on the effect of magnetic treatment and saline water application on water soluble magnesium (me L -1 ) are presented in Table 17. The water soluble magnesium of the soil samples was significantly influenced by magnetic treatments. Water soluble magnesium content of soil decreased significantly due to application of

31 both three and five pore volumes of magnetized water of varied salinities compared to application of magnetic untreated water. untreated water recorded highest water soluble magnesium content (0.81 and 0.75me L -1 ) compared to magnetic treated water (0.58 and 0.61me L -1 ) in both 3 and 5 pore volumes, respectively. Across salinity levels, the mean reduction in water soluble magnesium due to magnetic treatment was 28.4 and 18.6 per cent with three and five pore volumes of water application, respectively Water soluble sodium The data on the effect of magnetic treatment and saline water application on water soluble sodium (me L -1 ) is presented in Table 18. The trend of results in respect of water soluble sodium remained similar as observed in case of water soluble magnesium. The water soluble sodium of the soil samples was significantly influenced by magnetic treatments. Water soluble sodium content of soil decreased significantly due to application of both three and five pore volumes of magnetized water of varied salinities compared to application of magnetic untreated water. untreated water recorded highest water soluble sodium content (0.46 and 1.14me L - 1 ) compared to magnetic treated water (0.38 and 0.83me L -1 ) in both 3 and 5 pore volumes, respectively. Across salinity levels, the mean reduction in water soluble sodium due to magnetic treatment was 17.4 and 27.2 per cent with three and five pore volumes of water application. In contrast to water soluble magnesium, the per cent reduction in water soluble sodium was more with application of five pore volumes of water compared to three pore volumes. The interaction between salinity and magnetic treatment remained significant. Passing 8 EC magnetic untreated water recorded highest water soluble sodium values (0.72 and 2.17) in both 3 and 5 pore volumes, respectively Water soluble chloride The data on the effect of magnetic treatment and saline water application on water soluble chloride (me l -1 ) is presented in Table 19. Significant effect of magnetic treatments was observed on water soluble chloride content. Across salinity levels of waters, highest mean water soluble chloride was recorded under nonmagnetized water application (4.34 and 7.82me L -1 ) which decreased to 3.97 and 6.75me L -1 due to magnetized water application in both 3 and 5 pore volumes, respectively. As the salinity levels increased, there was an increase in water soluble chloride irrespective of magnetic treatment and water application rate. Irrespective of magnetic treatment and salinity of irrigation waters, significantly higher water soluble chloride was recorded with five pore volumes water application over three pore volumes Clay dispersion The data on the effect of magnetic treatment and saline water irrigation on clay dispersion (%) is presented in Table 20. The clay dispersion of the soil samples was significantly influenced by magnetic treatments. In general, significantly higher clay dispersion values were recorded in soils applied with magnetic untreated waters, irrespective of volume (three or five pore volumes). Soils applied with magnetic untreated water recorded and per cent clay dispersion which decreased due to magnetic treatment recording a clay dispersion of and per cent with three and five pore volumes of water application, respectively. Across salinity levels, the mean reduction in dispersible clay content due to magnetic treatment was 20.7 and 25.7 per cent with three and five pore volumes of water application. Irrespective of magnetic treatment, application of increased salinity waters resulted in increased clay dispersion values. The mean values of clay dispersion was significantly lower with five pore volumes of water application compared to three pore volumes, irrespective of magnetic treatment and salinity levels of water. Highest clay dispersion was recorded in magnetic untreated good water in 3 pore volume (27.45).

32 Table 13. Effect of magnetized water on exchangeable magnesium ECiw (ds m -1 ) untreated Exchangeable magnesium (me 100 g -1 soil) Three pore volumes treated Mean untreated Five pore volumes treated Mean 0.6 (GW) Mean treatment (M) Salinity levels (S) M x S treatment (M) Salinity levels (S) M x S SEm.± CD (P=0.05) Table 14. Effect of magnetized water on exchangeable sodium ECiw (ds m -1 ) untreated Three pore volumes Exchangeable sodium (me 100 g -1 soil) treated Mean untreated Five pore volumes treated Mean 0.6 (GW) Mean treatment (M) Salinity levels (S) M x S treatment (M) Salinity levels (S) M x S SEm.± CD (P=0.05)

33 Table 15. Effect of magnetized water on exchangeable sodium percentage ECiw (ds m -1 ) untreated Three pore volumes treated Exchangeable sodium percentage Mean untreated Five pore volumes treated Mean 0.6 (GW) Mean treatment (M) Salinity levels (S) M S treatment (M) Salinity levels (S) M S Sem.± CD (P=0.05) Table 16. Effect of magnetized water on water soluble calcium Eciw (ds m -1 ) untreated Three pore volumes treated Water soluble calcium (me L -1 ) Mean untreated Five pore volumes treated Mean 0.6 (GW) Mean treatment (M) Salinity levels (S) M x S treatment (M) Salinity levels (S) M x S SEm.± CD (P=0.05) NS

34 Table 17. Effect of magnetized water on water soluble magnesium ECiw (ds m -1 ) untreated Three pore volumes treated Water soluble magnesium (me L -1 ) Mean untreated Five pore volumes treated Mean 0.6 (GW) Mean treatment (M) Salinity levels (S) M x S treatment (M) Salinity levels (S) M x S SEm.± CD (P=0.05) NS Table 18. Effect of magnetized water on water soluble sodium ECiw (ds m -1 ) untreated Three pore volumes treated Water soluble sodium (me L -1 ) Mean untreated Five pore volumes treated Mean 0.6 (GW) Mean treatment (M) Salinity levels (S) M x S treatment (M) Salinity levels (S) M x S SEm.± CD (P=0.05)

35 Table 19. Effect of magnetized water on water soluble chloride Water soluble chloride (me L -1 ) ECiw (ds m -1 ) untreated Three pore volumes treated Mean untreated Five pore volumes treated Mean 0.6 (GW) Mean treatment (M) Salinity levels (S) M x S treatment (M) Salinity levels (S) M x S SEm.± CD (P=0.05) NS NS Table 20. Effect of magnetized water on clay dispersion ECiw (ds m -1 ) untreated Three pore volumes treated Clay dispersion (%) Mean untreated Five pore volumes treated Mean 0.6 (GW) Mean treatment (M) Salinity levels (S) M x S treatment (M) Salinity levels (S) M x S SEm.± CD (P=0.05) NS

36 4.3 Effect of magnetized water on leaching efficiency of salts Electrical conductivity (ds m -1 ) of leached soil A saline soil (7.2 ds m -1 ) was leached with marginally saline water of 2 ds m -1. The amount of leaching water used consisted of 1, 2, 3, 4 and 5 pore volumes. Irrespective of magnetic treatment, incremental volumes of water passed progressively removed salts from the soil (Table 21). The first pore volume of water when applied did not amount to any leaching but was approximately enough to saturate the soil. Even then it contributed for a marginal increase in the soil salinity in soil applied with magnetized water. Further, when more and more pore volume of water was passed through the soil, the salinity values decreased. The decrease was from 7.20 to 1.15 ds m -1 under non-magnetized water treatment compared to a decrease from 7.3 to 1.08 ds m -1 under magnetized water treatment. The per cent decrease in soil salinity was 84.0 and 85.2 for non-magnetized and magnetized water treatment, respectively. Under magnetized water treatment, faster removal of salinity was observed than in soils applied with non-magnetized water. For example, passing two pore volumes of non-magnetized water removed 50.7 per cent initial salts (initial salinity: 7.2 ds m -1 and after passing 2 pore volumes: 3.55 ds m -1 ) while the same of volume of water passing resulted in removal of 59.2 per cent of initial salts (initial salinity: 7.3 ds m -1 and after passing 2 pore volumes: 2.98 ds m -1 ) when magnetically treated Electrical conductivity (ds m -1 ) of leachate The electrical conductivity values of leachates leached with magnetized water were significantly higher compared to leaching with non-magnetized water as recorded after leaching with each pore volume (Table 22). The electrical conductivity values of leachates were higher during initial phase of leaching and decreased with progressive leaching with higher pore volume of water both under non-magnetized and magnetized water leaching. After leaching with each pore volume of water, leachate of magnetized water treatment contained higher salinity than under non-magnetized water leaching. After passing five pore volumes of water, the mean salinity of leachate leached with non-magnetized water was ds m -1 while, for magnetized water leaching, it was ds m Effect of magnetic water treatment on germination and early growth of sunflower Germination percentage at 5 DAS Germination of sunflower seeds was significantly influenced by magnetic treatments (Table 23). Highest mean germination was observed in magnetized water treatment (75%) compared to nonmagnetized water treatment (61%). As the salinity levels increased, germination of sunflower seed decreased, more so under non- magnetized water treatment. Even with good water use, magnetized water treatment registered a germination percentage of 90 while it was only 75 per cent under nonmagnetized water treatment. In case of non-magnetized water treatment, the germination percentage decreased to 45 with 8 EC irrigation water while it decreased to only 70 per cent under magnetized water treatment at the same level of saline irrigation Plant height The plant height of sunflower at 30 DAS was significantly influenced by magnetic treatments as well as salinity levels (Table 24). The highest plant height (27.53 cm) was recorded in the magnetic water treated plants compared to magnetic untreated plants (22.09 cm). Among the salinity levels, the highest plant height was recorded in 0.6 EC water in both magnetic treated and untreated treatment (40.25 and cm, respectively). Plants which received 8 EC water recorded the lower plant height i.e and 9.68 cm in both magnetic treated and untreated treatments, respectively. Similar trend was observed at 45 DAS. The highest plant height (33.63 cm) was recorded in magnetic treated plants compared to untreated plants (26.79 cm). Plants which received magnetic treated and untreated 6 EC water recorded lowest plant height (25.85 and cm, respectively), but it was significantly influenced by 4, 2 and 0.6 EC magnetic treated water received plants i.e , and cm and 24.78, and cm magnetic untreated water received plants, respectively. ally treated good water recorded maximum plant height at 30 and 45 DAS (40.25 and 41.95, respectively).

37 Table 21. Effect of leaching with magnetized water on soil salinity Pore volume untreated EC ( ds m -1 ) treated Mean treatment (M) Pore volume SEm.± CD (P=0.05) Table 22. Effect of leaching with magnetized water on EC of leachate Pore volume untreated EC ( ds m -1 ) treated 1 -* Mean treatment (M) Pore volume SEm.± CD (P=0.05) * - Leachate was not obtained

38 Table 23. Effect of magnetized water on germination of sunflower seeds ECiw (ds m -1 ) Germination percentage at 5 DAS untreated treated Mean 0.6 (GW) Mean treatment (M) Salinity levels (S) M x S SEm.± CD (P=0.05) NS Table 24. Effect of magnetized water on plant height (cm) of sunflower ECiw (ds m -1 ) untreated Plant height ( 30 DAS) treated Mean untreated Plant height (45 DAS) treated Mean 0.6 (GW) * - - Mean treatment (M) Salinity levels (S) M x S treatment (M) Salinity levels (S) M x S SEm.± CD (P=0.05) * - After 30 days plants not survived

39 Plate 3. Growth of sunflower at 30 days after sowing

40 Plate 4. Growth of sunflower at 45 days after sowing

41 4.4.3 Dry ma tter production (g plant -1 ) The magnetic treated water had significant effect on dry matter production (Table 25). Plants irrigated with magnetized water recorded significantly higher dry weight (1.33 g plant -1 ) compared to plants irrigated with non-magnetized water (0.77 g plant -1 ). Plants which received 0.6 EC water in both magnetic treated and untreated recorded highest plant dry weight (1.93 and 1.19 g plant -1 ) compared to other salinity water irrigated plants i.e. 2 EC (1.40 and 0.77 g plant -1 ), 4 EC (1.29 and 0.60 g plant -1 ) and 6 EC (0.69 and 0.52 g plant -1 ), respectively. Plants irrigated with non-magnetized 6 EC water (0.52 g plant -1 ) was on par with 4 EC (0.60 g plant -1 ), but remained significantly inferior over 0.6 and 2 EC (1.19 and 0.77 g plant -1, respectively) water irrigated treatments. The interaction between salinity and magnetic treatment remained significant. Passing good magnetic treated water recorded highest dry weight values (1.93) at 45 DAS Sodium content (%) The sodium content in sunflower plant was significantly influenced by magnetic treatments (Table 26). Maximum tissue sodium content was recorded in plants irrigated with magnetic untreated water (0.61 per cent) compared to plants irrigated with magnetic treated water (0.43 per cent). Sodium content of plants increased with increase in salinity levels. Plants irrigated with magnetized and non-magnetized 6 EC water recorded highest sodium content (0.74 and 1.11 per cent, respectively) compared to magnetized 0.6, 2 and 4 EC (0.17, 0.26 and 0.53 per cent, respectively) and non-magnetized 0.6, 2 and 4 EC water (0.23, 0.35 and 0.75 per cent, respectively), water irrigated plants Potassium (%) The plants irrigated with magnetic untreated water recorded highest potassium content (1.67 per cent) compared to magnetic treated (1.59 per cent) (Table 27). Highest potassium content was recorded in plants irrigated with magnetic treated and untreated 4 EC water (1.79 and 1.85 per cent respectively) followed by 2 EC (1.66 and 1.74 per cent, respectively) and 0.6 EC (1.54 and 1.62 per cent, respectively). However, the lowest potassium was recorded in 6 EC water received plants under both magnetized and non-magnetized water irrigations (1.36 and 1.46 per cent, respectively) K / Na ratio Across salinity levels, the plants irrigated with magnetized water recorded highest K / Na ratio (5.17) compared to non-magnetized water irrigation (3.95). The K/Na ratio also decreased considerably due to increased salinity in irrigation water. Though both K and Na decreased due to magnetic treatment, it was clear from the Tables 26 and 27 that the decrease was of lesser magnitude in K content (5 per cent) but higher in Na content (29.5 per cent) which contributed for higher K/Na ratio magnetized water treatment (Table 28).

42 Table 25. Effect of magnetized water on dry weight of sunflower plant ECiw (ds m -1 ) Plant dry weight (g plant -1 ) at 45 DAS untreated treated Mean 0.6 (GW) * - - Mean treatment (M) Salinity levels (S) M x S SEm.± CD (P=0.05) * - After 30 days plants not survived Table 26. Effect of magnetized water on sodium content (%) in sunflower plant ECiw (ds m -1 ) Sodium untreated treated Mean 0.6 (GW) * - - Mean treatment (M) Salinity levels (S) M x S SEm.± CD (P=0.05) * - After 30 days plants not survived

43 Table 27. Effect of magnetized water on potassium content (%) in sunflower plant ECiw (ds m -1 ) Potassium untreated treated Mean 0.6 (GW) * - - Mean treatment (M) Salinity levels (S) M x S SEm.± CD (P=0.05) * - After 30 days plants not survived Table 28. Effect of magnetized water K / Na ratio in sunflower plant ECiw (ds m -1 ) K / Na ratio untreated treated Mean 0.6 (GW) Mean

44 DISCUSSION The results of the experiments conducted during 2012 at College of Agriculture, UAS, Dharwad to study the effect of magnetic treatment on irrigation water quality and the effect of magnetic water on soil properties and other aspects of soil and crop are discussed in this chapter. 5.1 Effect of magnetic treatment on irrigation water quality In the magnetically treated water, there are maximum four hydrogen bridge connections containing protons that spin to the same direction. These are called clusters. Water that is completely organized consists of clusters. The clusters are not stable but very sensitive and unstable units. The influence of the magnetic fields on water is reported to change the dimensions of that clusters, which affects the physical properties of water. Consequent to changes in the physical properties of water, the quality of irrigation water is also reported to get influenced. The effect of magnetic treatment of saline irrigation waters on their quality parameters is discussed in the following paragraphs ph Irrespective of salinity of water, one time magnetic treatment significantly decreased water ph (Fig. 2). However, with subsequent magnetic exposures (two times and three times passed), the water ph marginally increased. With higher salinity waters (12 and 16 ds m -1 ), the ph of three times magnetic treated water recorded ph values greater than the initial ph of water. It was interesting to note that, 12 EC water recorded lower ph values compared to lower and higher salinity waters. From these observations, it was clear that the effect of magnetic treatment on water ph was widely varied. This has led to different streams of opinions regarding the effect of magnetic treatment on water ph. The variable changes in water ph due to magnetic treatment were reported by many researchers (Smikhina, 1981; Srebrenik et al., 1993; Amiri and Dadkhah, 2006; Otsuka and Ozeki, 2006). Parsons et al. (1996) recorded a decrease of 0.5 ph units after passing water through a magnetic treatment device. Chang and Weng (2008) reported changes in hydrogen bonding as the possible reason for the change in ph due magnetic field exposure. Grewal and Maheshwari (2011) observed some changes in the physical and chemical properties of water (hydrogen bonding, polarity, surface tension, conductivity, ph and solubility of salts) due to magnetic treatment. They attributed change in ph to mainly changes in hydrogen bonding. The results of this study showed a significant increase in ph with increase in the frequency of magnetic treatment from one time to two times. Similar result was reported by Alkhazan and Saddiq (2010) Electrical conductivity (ds m -1 ) The one time magnetic treatment of irrigation waters significantly decreased the electrical conductivity of water (Fig. 3). However, with subsequent magnetic exposures (two times and three times passed) the water electrical conductivity marginally increased. Across salinity levels, the electrical conductivity values recorded were significantly lower in magnetic treated water (8.03 ds m -1 ) compared to magnetic untreated water (8.12 ds m -1 ). Malkin (2002) also reported a decrease in the electrically conductivity of the magnetic treated water samples in his experiment. The decreased electrical conductivity of water due to magnetic treatment was ascribed to physical changes caused in fine colloidal molecules (in the state of constant motion resembling Brownian motion) and electrolytic substances resulting in increased bonding of ions on colloidal molecules (Alkhazan and Saddiq, 2010 and Kronenberg, 1985). Chang and Weng (2008) reported that the structure of water was more stable and the ability of the water molecules to form hydrogen bond was enhanced by magnetic field. Changes in physical and chemical properties of water such as hydrogen bonding, conductivity and solubility of salts is because of magnetic field exposure (Smikhina.1981, Srebrenik et al., 1993, Amiri and Dadkhah, 2006, Otsuka and Ozeki, 2006). The applied magnetic field may affect the formation of hydrogen bonds of water molecules and that may lead to conformational changes. These changes may be the reasons for the observed variations in conductivity (Ibrahim, 2006).

45 8.2 untreated Two times passed One time passed Three times passed ph (GW) EC iw (ds m -1 ) Fig. 2. Effect of magnetic treatment on ph of irrigation waters 16 untreated Two times passed One time passed Three times passed EC (ds m -1 ) (GW) EC iw (ds m -1 ) Fig. 3. Effect of magnetic treatment on salinity (EC, ds m -1 ) of irrigation waters

46 5.1.3 Cations The magnetic treatments of water significantly influenced calcium, magnesium and sodium content of the irrigation water (Fig. 4). Significantly higher calcium content was recorded in magnetic untreated water (16.18me L -1 ) under all salinity levels compared to magnetic treated water (15.76me L -1 ). untreated water also recorded higher magnesium concentration (11.71me L -1 ) compared to magnetic treated water (11.45me L -1 ). This may be due to the slowing down effect of mineral ions due to crystallization and precipitation processes induced by the magnetic treatment. Similar result was reported by Noran et al. (1996). Calcium and magnesium contents increased with increase in salinity levels in both magnetic treated and untreated water samples. This was mainly due to increasing predominance of salts in saline waters. Sodium content was also significantly influenced by magnetic treatments. untreated water registered higher sodium concentration (62.83me L -1 ) which decreased due to magnetic treatment (48.12me L -1 ). It is believed that magnetic force breaks hydrogen bonds between water molecules and ions and the ions separated combine with elements and precipitate. (Noran et al., 1996). Chang and Weng (2008) remarked that the enhanced mobility of the ions under a magnetic field may cause serious damage to the hydrogen bond network in the high Na concentration solution. Conversely, in the low-concentration solution, the structural behavior may be dominated by the properties of the water molecules and hence the hydrogen bonding ability may be enhanced with increased magnetic field Sodium adsorption ratio (SAR) Consequent to change in calcium, magnesium and sodium contents, the SAR of water was also significantly influenced by magnetic treatments (Fig. 5). Irrespective of magnetic treatments and salinity levels of water, the SAR values decreased significantly from 15.68me L -1 (magnetic untreated) to 12.32me L -1 due to magnetic field treatment. However, the SAR values significantly increased due to increasing salinity load in irrigation waters. In both 0.6 and 4 EC water, the SAR remained within the safe limit of 10 but, increased beyond 10 as salinity of water was 8, 12 and 16 ds m -1. This was mainly because of increasingly higher predominance of sodium over calcium plus magnesium in higher salinity waters Anions Significant effect of magnetic treatments was noticed with respect to anions. Irrespective of salinity of water, in general, the chloride content decreased due to magnetic treatment (Fig. 6). Passing water two (41.72me L -1 ) and three times (41.44me L -1 ) through the magnetic device significantly reduced the mean chloride contents over magnetic untreated water (42.06me L -1 ) though; passing once through the magnetic device had only marginal effect. Obviously, chloride contents increased significantly with increase in salinity of water. Results on these lines were reported by Colic and Morse (1999). They observed a reduction in chloride by per cent due magnetic treatment compared to normal irrigation water. Bicarbonate concentration of the water was also significantly influenced by magnetic treatments (Fig. 7). Across salinity levels and magnetic treatments, the bicarbonate content decreased significantly due to magnetic treatment. untreated water had the bicarbonate content of 1.57me L -1 which decreased due to magnetic treatment (1.44me L -1 ). The results are in agreement with the findings of Colic and Morse (1999) who reported 30 per cent reduction in bicarbonate content in magnetized water compared to normal irrigation water. Madsen (2004) attributed this reduction to accelerated crystallization of sparingly soluble diamagnetic salts of weak acids such as carbonates due to magnetic field exposure, lowering subsequently the contents of bicarbonates and carbonates in water. However, with increased frequency of magnetization (two times and three times passed), a significant increase in bicarbonate content was observed but still remained significantly lower than the nonmagnetized water Residual sodium carbonate (RSC) Irrespective of treatments, the RSC values remained negative indicating higher predominance of calcium plus magnesium than bicarbonates. The magnetic treatments of water significantly influenced the RSC of water (Fig. 8). The RSC values increased significantly due to magnetic treatment. Irrespective of magnetic treatments and salinity levels of water, magnetic treated water recorded higher RSC value (-25.76me L -1 ) compared to magnetic untreated water ( me L -1 ). These changes in RSC values are attributed to changes in the concentration of Ca, Mg and bicarbonate contents due to magnetic treatment. It was interesting to note that with increased frequency of magnetization, the RSC values decreased and the three times passed water recorded the lowest RSC of me L -1 which however, was significantly higher than the RSC of magnetic untreated water.

47 (GW) Cations (me l -1 ) untreated One time passed Two times passed Three times passed untreated One time passed Two times passed Three times passed untreated One time passed Two times passed Three times passed Calcium Magnesium Sodium Fig. 4. Effect of magnetic treatment on calcium, magnesium and sodium content (me L -1 ) of irrigation waters

48 (GW) Sodium adsorption ratio untreated One time passed Two times passed Three times passed Fig. 5. Effect of magnetic treatment on SAR (me l -1 ) of irrigation waters

49 90 80 untreated Two times passed One time passed Three times passed Chloride (me l -1 ) (GW) EC iw (ds m -1 ) Fig. 6. Effect of magnetic treatment on chloride content (me L -1 ) of irrigation waters

50 untreated Two times passed One time passed Three times passed Bicarbonate (me l -1 ) (GW) EC iw (ds m -1 ) Fig. 7. Effect of magnetic treatment on bicarbonate content (me L -1 ) of irrigation waters

51 0.6 (GW) Residual sodium carbonate (me l -1 ) untreated One time passed Two times passed Three times passed Fig. 8. Effect of magnetic treatment on RSC (me L -1 ) of irrigation waters

52 0.6 (GW) ph values untreated EC iw (ds m -1 ) treated Fig. 9. Effect of magnetized water on soil ph and salinity (EC 2.5, ds m -1 ) at three pore volumes 0.6 (GW) EC (ds m -1 ) untreated EC iw (ds m -1 ) treated Fig. 9. Effect of magnetized water on soil ph and salinity (EC2.5,ds m- 1 ) at three pore volumes

53 0.6 (GW) ph values untreated EC iw (ds m -1 ) treated Fig. 10. Effect of magnetized water on soil ph and salinity (EC 2.5, ds m -1 ) at five pore volumes (GW) EC (ds m -1 ) untreated EC iw (ds m -1 ) treated Fig.10 Effect of magnetized water on soil ph and salinity (EC2.5,dsm- 1 ) at five pore volumes

54 5.2 Effect of magnetized water on soil properties ph The soil ph was significantly influenced by magnetic treatments as well as water salinity levels of waters (Fig. 9 and 10). Application of non-magnetized water recorded the ph of 7.85 and 7.91 which decreased to 7.48 and 7.62 at three and five pore volumes, respectively due to magnetic treatment. Similar observation was made by Grewal and Maheshwari (2011) who observed a significant decrease in soil ph 1:5 after the harvest of celery and snow pea due to irrigation with magnetically treated water compared to non-magnetized control. They speculated that soil acidification may be due to release of organic acids within the rhizosphere of plants irrigated with magnetized water compared with plants irrigated with non-magnetized water. They opined that organic acids released in rhizosphere may be responsible for desorption of nutrients and making them more available to plants. Musa and Hamoshi (2012) opined that the magnetic field might create more hydroxyl groups resulting in reduction in the acidity of magnetized water. Similar result was reported by Yazied et al. (2012) were the soil ph values decreased as a result of magnetic treatments Electrical conductivity Electrical conductivities (EC 1:2.5, ds m -1 ) of the soil samples were significantly influenced by magnetic treatments as well as water salinity levels (Fig. 9 and 10). A normal soil (non saline) passed intermittently with magnetic untreated water recorded the electrical conductivity of 0.26 and 1.09 ds m -1, which increased to 0.39 and 1.75 ds m -1 at three and five pore volumes, respectively due to magnetic treatment. Maheshwari and Grewal (2009) also observed a significant increase in soil EC 1:5 after harvest of snow pea plants when irrigated with magnetically treated potable water, recycled water and 1000 ppm saline water. The review of literature revealed that application of magnetic field on water can influence its conductivity in two ways. In natural water, the dissolved salts form ions which are surrounded by dipolar water molecules forming macro water clusters. Due to magnetic effect, the increased vibrations cause macro clusters to break apart and form micro clusters and to some extent release free ions which help to increase electrical conductivity. This may also happen due to increased alignment of micro water clusters formed due to magnetic treatment and helping in higher conductivity. Hilal et al. (2002) reported that magnetized water dissolved slightly soluble salts such as carbonates, phosphates and sulfates which might have contributed for increased conductivity. Ibrahim (2006) opined that application of magnetic field may affect the formation of hydrogen bonds of water molecules and that may lead to conformational changes. These changes lead to change in electrical conductivity. On the contrary, Mohamed (2013) reported a decrease in electrical conductivity of sandy soil irrigated with magnetized saline water in tomato Exchangeable cations treatments significantly influenced exchangeable calcium, magnesium and sodium contents of soil (Fig. 11 and 12). Soils passed with magnetic untreated water recorded highest calcium and sodium contents which decreased due to magnetic treatment with intermittent passing of 3 and 5 pore volumes of water while, the reverse trend was observed in exchangeable magnesium. The exchangeable magnesium content of soil increased due to irrigation with magnetized water. The reasons for the decrease in exchangeable calcium and sodium contents had been explained on the basis of interaction between solute and solvent with the effect of magnetic field. The Lorentz force caused by the magnetic treatment is reported to disturb the system by accelerating the movement of the charged particles. This effect is expected to weaken the interaction between solute and solvent (Guo et al., 2011). Because of this, it is more likely for ions to contact with each other and form ion pairs (Guo et al., 2011) thereby decreasing exchangeable ions. Alternatively, due to magnetic treatment, the electrical charge and hydrogen bonding in water is reported to enhance and lead to stronger hydrogen bonding between water and clay colloids, leaving cations to dominate in soil solution (Ashrafi et al., 2012) which may further undergo ion pairing Exchangeable sodium percentage (ESP) The ESP of soil samples was significantly influenced by magnetic treatments though the ESP values in general, remained low (Fig. 13). The highest ESP was recorded in soils passed with magnetic untreated water i.e.1.34 and 1.98 per cent which decreased to 1.01 and 1.62 per cent in both 3 and 5 pore volumes, respectively. The ESP increased with increase in salinity levels. The decrease in ESP was mainly due to decrease in exchangeable sodium content under magnetic water use.

55 0.6 (GW) Exchangeable calcium (me 100 g -1 soil) untreated treated 0.6 (GW) Excha ngeable sodium (me 100 g -1 soil) untreated EC iw (ds m -1 ) treated 0.6 (GW) Exchangeable magnesium (me 100 g -1 soil) untreated EC iw (ds m -1 ) treated Fig.11 Effect of magnetized water on exchangeable calcium, magnesium and sodium (me 100 g- 1 soil) at three pore volumes

56 0.6 (GW) Exchangeable calcium (me 100g -1 soil) untreated EC iw (ds m -1 ) treated Fig. 12. Effect of magnetized water on exchangeable calcium, magnesium and sodium (me 100 g -1 soil) at five pore volumes 0.6 (GW) Exchangeable magnesium (me 100 g -1 soil) untreated EC iw (ds m -1 ) treated 0.6 (GW) Exchangeable sodium (me 100 g -1 soil) untreated EC iw (ds m -1 ) treated Fig.12 Effect of magnetized water on exchangeable calcium magnesium and sodium (me 100 g -1 soil) at five pore volumes

57 5.2.5 Water soluble cations Significant effect of magnetic treatments was observed on water soluble cations (Fig. 14 and 15). The higher water soluble cal cium, magnesium and sodium contents were recorded under non-magnetized water application which decreased due to magnetized water application, in both 3 and 5 pore volumes. The decreasing of sodium concentration in the soil solution by magnetic water has been reported by Bogatin (1999), Saliha (2005) and Zangeneh et al. (2010). Gehr et al. (1995) made similar observation with water soluble calcium. In contrast, Saliha (2005) and Zangeneh et al. (2010) reported an increase in calcium concentration in magnetic treatments. They attributed this differential behaviour to the effect of magnetic field on hydrogen bonding Water soluble anions Significant effect of magnetic treatments was observed on water soluble anions (Fig. 16). The highest water soluble chloride was recorded under non-magnetized water application, which decreased due to magnetized water application, in both 3 and 5 pore volumes. Water soluble anions are mainly depending on water soluble cations. Water soluble anions increases with increase in water soluble cations it may be due to differential behaviour to the effect of magnetic field on hydrogen bonding Clay dispersion The dispersible clay content of soil samples was significantly influenced by magnetic treatments (Fig. 17). In general, magnetic treatment significantly decreased the dispersible clay content over non-magnetized water use. Clay dispersion is mainly a function of clay type, composition of exchange complex and the electrolyte content. The decrease in ESP of soils due to magnetic treatment has improved the formation of aggregates and thereby decreased the dispersible clay content. Clay dispersion also decreased with increase in salinity levels. Relatively high salt concentration in the soil solution essentially pushes adsorbed cations closer to the soil particles surface, keeping soil aggregates together (Miller and Donahue, 1995; Buckman and Brady, 1967; Shainberg and Letey, 1984). 5.3 Effect of magnetized water on leaching efficiency of salts Electrical conductivity (ds m -1 ) of leached soil To investigate the effect of magnetized irrigation water on leaching efficiency of salts, a column experiment was carried out. A saline soil having a salinity of 7.2 ds m -1 was leached with marginal saline water of 2.0 ds m -1. Both soil salinity and salinity of leachate were estimated after leaching with predetermined volume/s of water. The magnetized water significantly influenced the salinity of the leached soil (Fig. 18). Soils leached with magnetized water showed significantly lower salinity values, irrespective of volume of water passed over magnetic untreated water leaching. This was obviously due to removal of more salts by magnetized water than non- magnetized water. Across volume of water applied, soil columns leached with magnetized 2 EC water had a significantly lower salinity of 2.78 ds m -1 compared to leaching with non- magnetized water (3.15 ds m -1 ). It was found that salt removal decreased with progressive leaching. Alleman (1985) showed that desalination of a saline soil was 29 per cent greater in the first leaching and 33 per cent greater in the second leaching with magnetized water compared to untreated water Electrical conductivity (ds m -1 ) of leachate Electrical conductivity of leachates was significantly influenced by magnetic water treatment (Fig. 18). The magnetic treatment caused a significant increase in the salinity of leachates compared to non magnetized water indicating more removal of salts from the saline soil. It was found that salt removal decreased with subsequent leaching frequency or with increased pore volumes. Total soluble salts concentration in the first leachate of all columns was higher compared with subsequent leachates while it was lower in the last leachate. Similar results were reported in literature. Mohammed and Baseem (2013) showed that electrical conductivity values (EC, dsm -1 ) in water leachates of columns irrigated with magnetized water were higher compared with non-magnetized water. He concluded that magnetizing the irrigation water plays an important role in removing the soluble salts from the soil. Hilal et al. (2002) reported that magnetized water not only increased the leaching of excess soluble salts but also dissolved slightly soluble salts such as carbonates, phosphates and sulfates in soil.

58 Three pore volumes 0.6 (GW) Exchangeable sodium percentage untreated EC iw (ds m -1 ) treated Fig. 13. Effect of magnetized water on exchangeable sodium percentage Five pore volumes (GW) Exchangeable sodium percentage untreated EC iw (ds m -1 ) treated Fig.13 Efeect of magnetized water on exchangeable sodium percentage

59 (GW) Calcium (me 1-1 ) untreated EC iw (ds m -1 ) treated Fig. 14. Effect of magnetized water on water soluble calcium, magnesium and sodium (me L -l ) at three pore volumes 0.6 (GW) Magnesium (me 1-1 ) untreated EC iw (ds m -1) treated 0.6 (GW) Sodium (me 1-1 ) untreated EC iw (ds m -1 ) treated Fig.14 Effect of magnetized water on water soluble calcium, magnesium and sodium (me L -1 ) at three pore volumes

60 0.6 (GW) Calcium (me 1-1 ) untreated EC iw (ds m -1 ) treated Fig. 15. Effect of magnetized water on water soluble calcium, magnesium and sodium (me L -l ) at five pore volumes 0.6 (GW) Magnesium (me 1-1 ) untreated EC iw (ds m -1 ) treated 0.6 (GW) Sodium (me 1-1 ) untreated EC iw (ds m -1 ) treated Fig.15 Effect of magnetized water on water soluble calcium, magnesium and sodium (me L -1 ) at five pore volumes

61 (GW) Chloride (me l-1) untreated treated untreated treated Three pore volumes EC iw (ds m -1 ) Five pore volumes Fig. 16. Effect of magnetized water on water soluble chloride (me L -1 ) Fig.16. Effect of magnetized water on water on water soluble chloride ( me L- 1 )

62 Three pore volumes 0.6 (GW) Clay dispersion (%) untreated EC iw (ds m -1 ) treated Fig. 17. Effect of magnetized water on clay dispersion (%) Five pore volumes 0.6 (GW) Clay dispersion (%) untreated EC iw (ds m -1 ) treated Fig.17. Effect of magnetized water on clay dispersion) %)

63 EC of soil (ds m -1 ) untreated Pore volumes treated Fig. 18. Effect of leaching with magnetized water on EC of soil and leachate EC of leachate (ds m -1 ) untreated Pore volumes treated Fig.18. Effect of leaching with magnetized water on EC of soil and leachate

64 0.6 (GW) Germination at 5 DAS (%) untreated EC iw (ds m -1 ) treated Fig. 19. Effect of magnetized water on germination percentage and plant height (cm) of sunflower (GW) Plant height (cm) untreated treated untreated treated 30 DAS EC iw (ds m -1 ) 45 DAS Fig.19. Effect of magnetized water on germination percentage and plant height (cm) of sunflower

65 0.6 (GW) Plant dry weight (g plant -1 ) untreated treated Fig. 20. Effect of magnetized water on dry weight (g plant -1 ) of sunflower plant Fig.20. Effect of magnetized water on dry weight (g plant - 1 ) of sunflower plant

66 0.6 (GW) Sodium content (%) untreated EC iw (ds m -1 ) treated Fig. 21. Effect of magnetized water on sodium and potassium content in sunflower plant 0.6 (GW) Potassium content (%) untreated treated EC iw (ds m -1 ) Fig.21.Effect of magnetized water on sodium and potassium content in sunflower plant