Urea Foliar Application as a Partial Substitution of Soil-Applied Nitrogen Fertilization for Some Maize Cultivars Grown in Newly Cultivated Soil

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1 Australian Journal of Basic and Applied Sciences, 5(7): , 2011 ISSN Urea Foliar Application as a Partial Substitution of Soil-Applied Nitrogen Fertilization for Some Maize Cultivars Grown in Newly Cultivated Soil 1 Afifi M.H.M, 2 R.Kh. M. Khalifa and 3 Camilia, Y. El-Dewiny 1 Field Crop Research Dept., 2 Fertilization Technology Dept., 3 Soil & Water Use D.,ept National Research Centre, Dokki, Cairo, Egypt Abstract: Two field experiments were carried out during the two summer seasons of 2007 and 2008 seasons. The trials implemented in El-Emam El-Ghazaly Village, El-Bostan Provience, El-Behaira Governorate, Egypt. The objective was to investigate response of growth, yield, and yield components and nutrients uptake of three maize cultivars, i.e. Giza: 310,324 and 103 to urea foliar application as a partial substitution of soil-applied nitrogen fertilization to minimize its quantity for optimizing fertilizer use and minimizing under-ground water pollution. Treatments were the recommended rate of soil-applied nitrogen fertilization (control), in addition the three treatments viz., 50%, 75%and 100% of recommended rate of soil-applied nitrogen combined with three foliar sprays with urea for both at rate of 15g/liter (1.5%) at 30,45 and 60 days after sowing. The results showed that urea foliar application significantly increased growth yield and yield components of maize varieties as compared with unsprayed treatment in both seasons and the highest values were obtained from 100% of recommended rate of soil-applied nitrogen fertilization with all varieties. However there were no significant differences between 100% and 50% or 75% with urea foliar application in some studied traits of growth yield and yield components and there were significant differences due to varieties and interactions between varieties and urea foliar spray. The results indicated that urea foliar application enhanced nutrients uptake by plants of all maize varieties and increased grains nutrients content. Key words: Maize varieties, soil-applied nitrogen, urea foliar spray, nutrient content, nutrient uptake, newly cultivated soil. INTRODUCTION Maize (Zea mays L.) is one of the most important cereal crops in Egypt as a food crop for both humans and animals and in the same time it needs highly rate of N applied reached to 300kg urea /fed. in normal soils (Nofal and Hinar, 2003) these large quantities of the mineral N-fertilizer cause environmental pollution through drainage water and other N-contaminated water (Mantripukhri, 2006). Maize can be grown as a supplementary crop to decrease the gap between the import and the local production of oil in Egypt. Hence, its cultivation was recently expanded in the newly reclaimed sandy soils which characterized with low fertility, high PH value and low organic matter content. Meanwhile high demand of N-fertilizer requirement which led to high leaching of nitrogen fertilizer through its high filtration rates. However, application of N-fertilizer as urea foliar spray may decrease such losses. El-Fouly and El-Sayed, (1995) reported that N-losses from the recommended N-dose for corn as a summer crop were 50% through leaching and /or denitrification. In this connection, El-Fouly and Fawzi, (1996) mentioned that N-losses in summer crops are very high and efficiency of N-fertilizers used is very low. Thus, urea foliar feeding as a supplement or a partial substitution to soil fertilizer application was studied, in this connection, efficient and positive response of some field crops due to urea foliar feeding combined with N-fertilizers soil application were recorded such as, Ahmad, (1998) on maize, wheat and cotton crops and Abdel-Maguid, (2004) on potato. In addition, the enhancing effect of urea foliar application was also reported on legumes by several investigators among of them, Saleh et al.,(2000); Attia and El-Dsouky, (2001); Zeidan, (2002) El-Kramany and Mirvat Gobarh, (2005) on faba bean and El- Kramany et al., (2003) on mungbean plants. In addition, the beneficial effect of foliar nutrition of N, P, and K in mineral form compounds or Humic acid containing N, P, and K as a supplemental or a partial substitution to soil application were reported by Brar and Brar, (2004) on cotton; Abou El-Nour and Abdel-Maguid, (2003) Corresponding Author: Camilia, Y. El- Dewiny, Soil & Water Use Department, National Research Centre, Dokki Cairo, Egypt. 826

2 on maize; Shaaban et al., (2009) on wheat and Afifi et al., (2010) on faba bean.the objective of the present study was to investigate response of three hybrids of maize cultivars, i.e. Trible-hybrid (Giza: 310,324) and Single-hybrid (Giza 103) to substituting a part of the recommended soil-applied nitrogen fertilization by of soilapplied nitrogen fertilization by urea foliar application. MATERIAL AND METHODS Two field experiments were carried out on newly cultivated sandy soils at El-Bostan District, El-Emam El-Ghazaly Village, El-Behaira Governorate, Egypt, during the two consecutive summer seasons of 2007 and The trials were performed on three hybrids of maize (zea mays L.) cv. Trible-hybrid (Giza: 310,324) and Single-hybrid (Giza 103) to investigate response of substituting a part of the recommended soil-applied nitrogen fertilization by urea foliar application. A composite surface soil samples (0-30cm) were taken before sowing from the experimental site, air dried, passed through 2mm sieve pores for determination of physicchemical properties (Chapman and Pratt, 1978). The data of the analyzing are presented in Table (1) reveal that the experimental site soil is sandy in texture, tented to alkalinity in reaction, had low calcium carbonate content, very low in organic matter content, high in ph, Ec and Na contents very low in available K content and low available content of P, Mg, Ca, and micronutrients. Grains of maize were sown in hills 30cm apart at a rate of 15kg/fed., on June 5 th and May31th in 2007 and 2008 seasons, respectively. All plots of the experiment received 31kg P2O5/fed. as calcium super phosphate (15.5%P2O5) potassium was added at a rate of 48kg K2O/fed. as potassium sulphate (48% K2O). Also plants of all treatments received two foliar sprays of Fe, Zn and Mn in the mineral forms at a rate of 1.50g/l from three micronutrients at 30 and 45 days after sowing. The irrigation system was drip irrigation. Ammonium sulphate (20.6%N) and ammonium nitrate (33.5%N) was used to apply the N rates. Urea foliar application in each spray was at a rate of 15g/l water (1.5%). The first and the second of urea foliar spray were applied using the same solutions of the micronutrients using 250l/fed. Total N was determined in the dry grains using Kjeldahl method ; total P was photo metrically determined using molybdate-vanadate method while total K was determined using flame photometer. Micronutrients were measured using atomic absorption spectrophotometer, according to Chapman and Pratt, (1978). Treatments and Experimental Design: Four treatments were applied depending on combinations between soil-applied N rates and the four treatments were foliar sprayed with urea for all cultivars and the treatments were as follows: kgN/fed.as recommended (control) kgN/fed. + 3 urea foliar sprays kgN/fed. + 3 urea foliar sprays kgN/fed. + 3 urea foliar sprays. Samples of five guarded plants were taken at random from the three middle rows of each plot of the four replications at 70 days after sowing to measure the following growth parameters, plant height, stem dry weight/plant, leaves dry weight and number of leaves/plant. At harvest, ten guarded plants were taken at random from the three middle rows of each plot of the four replications to determine kernels weight, 100-grain weight and grain number /ear. All plants from each plot of the different treatments and varieties were collected to estimate yield/fed. The experimental design was split plot with four replicates, where varieties occupied the main plots, while the soil-applied N rates were allocated at random in the sub plots, each plot was 10.5m2 in area (1/400fed.). The data were statistically analyzed according to Snedecor and Cochran (1982), the least significant differences (LSD) was used to compare the treatments mean at 5% level of probability. Soil analysis were as follows:- Texture: Hydrometer method (Bouyoucos, 1954). PH and Ec: In 1:2.5 soil/water suspension (Chapman and Pratt, 1978). O.M: Black method (Isaac and Johnson,1984). CaCO3: Collin,s Calcimeter (Alison and Moodle,1965). P: NaH CO3Extraction at PH 8.5 (Olsen et al. 1954). K, Ca, Na and Mg: NH4-OAc extraction at PH7 (Jackson, 1973). Fe, Mn, Zn and Cu: DTPA extraction at PH7.3 (Lindsay and Norvell, 1978). 827

3 Table 1: physic-chemical properties of the experimental site. Item 2007 season 2008season Nutrient 2007 season 2008 season Sand% Available macronutrient (mg/100g) Silt% P 0.82 L 0.74 L Clay% 4 4 K 6.00 L 7.00 L Texture Sandy Sandy Mg L L PH 7.92 H 7.96 H Ca L L Ec(dS/m) 1.60 H 1.52 H Na 52 H 48 H CaCO3% 1.92 L 1.84 L Available micronutrient (mg/1000g) O.M% 0.48 VL 0.54 VL Fe 7.20 L 6.00 L Mn 6.40 L 5.50 L Zn 1.24 L 1.02 L Cu 0.40 L 0.32 L VL= very low, L=low, H= high, according to Ankerman and Large (1974) Results: I. Effect of Urea Foliar Application on Some Plant Growth Parameters: At the vegetative growth stage (70 days from sowing), significant results were obtained for all the studied characteristics of growth between soil-n fertilizer application and the combinations of soil with urea foliar application at the different rates of soil-n fertilization, (Table 2). The data clearly showed that there were significant differences between cultivars for all studied growth parameters, i.e. plant height, number of leaves / plant, leaves and stem dry weight /plant in booth seasons. The results also revealed that the variety of Triplehybrid (Giza 310) surpassed the other hybrid, Triple-hybrid (Giza324) and Single-hybrid (Giza103) and gave the highest values of growth parameters, in booth seasons. Concerning the effect of urea foliar spraying combined with all rates of soil- N application as compared with the soil application the data presented in Table (2) revealed that the studied growth parameters of maize hybrids were significantly increased with urea foliar spray combined with different rates of N-soil application, except at soil application of 50% of total recommended nitrogen treatment. The treatment of 100% soil application nitrogen rate combined with urea foliar adding resulted the highest values of growth parameters under study, in both seasons. Regarding the interaction effect between varieties and urea foliar application under different rates of nitrogen soil application, results showed significant effects in booth seasons and the highest values were obtained by 100% of soil application nitrogen rate combined with urea foliar adding treatment followed by75% of soil application nitrogen rate combined with urea foliar treatment, in booth seasons. II. Effect of Urea Foliar Application on Some Yield Components and Yield: Data presented in Table (3) indicated that there were significant differences between maize cultivars in some yield components, i.e. mean of ear weight and grain number / ear, while the differences between maize cultivars in respect of 100-grain weight and grain yield /fed. were not reached to the level of significant in both seasons. Data also revealed that Triple-hybrid (Giza324) and Single-hybrid (Giza103) gave the highest values of grain/fed. and some yield components in the first and second seasons, respectively. Regarding, the effect of urea foliar feeding as combined with N-soil application rates, data presented in Table (3) showed that some studied traits of maize hybrids were significantly increased as the application only of nitrogen fertilizer, except at soil application 50% of total recommended nitrogen treatment. Although, the treatment of 100% soil application nitrogen rate combined with urea foliar adding resulted the highest values of yield and yield components but the increases were not reached to the level of significant as compared with 75% soil application n of nitrogen rate combined with urea foliar application treatment. Regarding the interaction effect between varieties and urea foliar application under different rates of nitrogen soil application, results showed significant effect in booth seasons and the highest values were obtained by 100% of nitrogen rate soil application combined with urea foliar adding treatment followed by75% combined with urea foliar treatment, in booth seasons. III. Effect of Urea Foliar Application on Grains Nutrient Contents: Results presented in Tables (4&5) revealed that maize cultivars were significantly differed in their grain macro and micronutrients contents in both seasons. The most pronounced increases in N, P, Fe and Cu content of grains were recorded by Triple-hybrid (Giza 324) cultivar, while the highest values of grains content from K and Zn obtained by Single-hybrid (Giza 103) cultivar in both seasons. It is evident also from the results in the same Tables that urea foliar spray had significant effect on macro and micronutrients of grains in both 828

4 seasons under different rates of N-soil application. The data clearly indicate that the highest grain contents from N, P, K, Mn, Zn and Cu were obtained from the treatment of urea foliar spray + 100% of soil nitrogen application, while the highest grain Fe content was recorded the treatment of urea foliar spray + 75% of soil nitrogen application, in both seasons. Concerning the effect of the interaction between maize cultivars and urea foliar spraying under different rates of N-soil application, results revealed that Triple-hybrid (Giza 324) sprayed with urea and received 100% of total nitrogen rates as soil application gave the highest grain content from N, P, Fe and Cu, while Single-hybrid (Giza-103) resulted the highest K, Mn, and Zn grains content, in both seasons. Table 2: Some growth parameters of maize cultivars as affected by urea foliar spraying under different levels of N-soil application.(average of 2007 and 2008 seasons) Cultivars Urea treatments 2008 season 2009 season Plant height (cm) No of leaves/ Leaves dry Stem dry Plant height (cm) No of leaves/ Leaves dry Stem dry plant weight (g) weight (g) plant weight (g) weight (g) Trible-hybridGiza % soil-applied N(control) % + urea foliar %+ urea foliar %+ urea foliar Mean Trible-hybridGiza % soil-appli N(control) % + urea foliar %+ urea foliar %+ urea foliar Mean Single -hybrid Giza % soil-appli N(control) % + urea foliar %+ urea foliar %+ urea foliar Mean Mean of urea treatment 100% soil-appli N(control) % + urea foliar %+ urea foliar %+ urea foliar Mean LSD 0.05 Cultivar Urea treatment Cultivar X Urea Table 3: Yield and some yield components of maize cultivars as affected by urea foliar spraying under different levels of N-soil application..(average of 2007 and 2008 seasons) Cultivars Urea treatments 2008 season 2009 season Ear weight (g) Grain no./ear 100- grain Grain wt. Ear weight (g) Grain no./ear 100- grain Grain wt. weight (g) (kg/fed.)* weight (g) (kg/fed.)* Trible-hybridGiza % soil-applied N % + urea foliar %+ urea foliar %+ urea foliar Mean Trible-hybrid Giza % soil-applied N % + urea foliar %+ urea foliar %+ urea foliar Mean Single -hybrid Giza % soil-applied N % + urea foliar %+ urea foliar %+ urea foliar Mean Mean of urea treatment 100% soil-applied N % + urea foliar %+ urea foliar %+ urea foliar Mean LSD 0.05 Cultivar NS NS NS NS Urea treatment Cultivar X Urea *fed. = 0.42 ha Table 4: Nutrients uptake of maize grains cultivars as affected by urea foliar spraying under different levels of N-soil application..(average of 2007 and 2008 seasons) Cultivars Urea treatments g/kg grains mg/kg grains N P K Fe Mn Zn Cu Trible-hybrid Giza % soil-applied N % + urea foliar %+ urea foliar %+ urea foliar Mean Trible-hybrid Giza % soil-applied N % + urea foliar %+ urea foliar %+ urea foliar Mean Single -hybrid Giza % soil-applied N(control) % + urea foliar %+ urea foliar %+ urea foliar

5 Table 4: Continue. Mean Mean of urea treatment 100% soil-applied N % + urea foliar %+ urea foliar %+ urea foliar Mean LSD 0.05 Cultivar Urea treatment Cultivar X Urea Table 5: Nutrients uptake of maize grains cultivars as affected by urea foliar spraying under different levels of N-soil application.(average of 2007 and 2008 seasons) Cultivars Urea treatments g/kg grains mg/kg grains N P K Fe Mn Zn Cu Trible-hybrid Giza % soil-applied N(control) % + urea foliar %+ urea foliar %+ urea foliar Mean Trible-hybrid Giza % soil-applied N(control) % + urea foliar %+ urea foliar %+ urea foliar Mean Single -hybrid Giza % soil-applied N(control) % + urea foliar %+ urea foliar %+ urea foliar Mean Mean of urea treatment 100% soil-applied N(control) % + urea foliar %+ urea foliar %+ urea foliar Mean LSD 0.05 Cultivar Urea treatment Cultivar X Urea Discussion: Maize has higher production potential, specially under irrigated condition, and it is well-known that is heavy feeder of nitrogen (N) demands (Nanjappa et.al. 2001). Irrespective of nitrogen (N) soil or foliar supply, results revealed varietal differences between the three cultivars under study in terms of growth, yield, yield components and nutrients content of grains. It is worthy to mentioned that the results of the varietal differences of maize cultivars due to different rates of nitrogen fertilization in yield and its components is confirmed with the results obtained by Moursi et.al., (1983), El-Kholy, (1987) and Ahmed,(1989). In addition variable responses to the application of N fertilizer application have been observed by Karlen et.al. (1987) and Muchow, (1998). These variable responses between maize cultivars mainly due to the varietal differences N-use efficiency which mentioned by Novoa and Loomis, (1981) and Muchow, (1998). Results revealed significant increase in growth, yield, yield components and nutrients content by grains of three maize cultivars by urea foliar spraying under substitution of 25% from the total rate of soil-n application. In this concern, foliar urea has been effectively used as a fertilizer over the past 4-5 decades, having many benefits to recommend it as indicated by a review in respect of cereal crops usage (Gooding and Davies, 1992). In this respect, positive responses of urea foliar spraying on various agronomic crops were recorded as partial substitution of soilnitrogen application, Brar and Brar (2004) on cotton and Abdel-Maguid, (2004) on potato. In addition, comparison of soil vs. foliar application of urea on maize were studied in Pakistan which were reported by Ahmad, (1998) who mentioned that foliar spraying of urea was not superior to soil application, however, combination of soil + foliar application treatments showed positive responses and these treatments needs further examination, this means that the nitrogen applied through foliar feeding without any quantities of soil-n applied are not fairly enough to face the requirements of maize plants. These results are in agreement with those obtained by Mingel and Kirkby (1987); Miller et.al. (1998) and Ahmad, (1998) who stated that crops required a very high amount from macronutrients, and plant leaves are only able to take it by very small amounts. However, urea foliar feeding in combination with 75% of total recommended amounts of N-soil application, this indicates that substitution of 25% applied recommended rate of soil nitrogen fertilizer by foliar feeding did not negatively affect on plant growth or yield components. However, reducing the rate of applied soil nitrogen fertilizer to 50% of recommended rate combined with foliar feeding showed negative effect on growth, yield, yield components and nutrient uptake by grains. On the other hand, it is clear that Appling 100% of recommended rate of soil nitrogen fertilizer combined with urea foliar spray surpassed other treatments and showed the highest results of maize growth, yield and yield components as well as nutrients uptake. 830

6 From the above mentioned results, it could be concluded that it is better to substitute 25% of total recommended soil nitrogen fertilizer by urea foliar spraying to achieve nearly results results of the maize growth, yield and yield components and grain nutrients content. Acknowledgment The authors would like to express their gratitude to the project"micronutrients and other plant nutrition problems in Egypt"(NRC/GTZ) and the national coordinator Prof.Dr.Mouhamed M.El-fouly for their help and providing the work facilities. REFERENCES Abdel-Maguid, A.A., Urea foliar application to minimize soil applied N fertilization of surfaceirrigated potato. Minufiya J. Agric. Res., 29(4): Attia, K.K. and M.M. El-Dsouky, Effect of farmyard manure application and late foliar nutrition with nitrogen during pod-filling stage on yield and some nutrients content in seeds of faba bean. Assiut J of agriculture, Assiut University, Assiut, Egypt, 32(2): Ahmad, Nisar., Foliar fertilization in Pakistan: Status, Scope and Constraints.. Proc. Symp. Foliar Fertilization: A Technique to Improve Production and Decrease Pollution Dec. 1995, Cairo Eds. El- Fouly et al Ahmed, M.A., Effect of nitrogen fertilizer levels on yield and its components of some white and yellow maize cultivars grown in Egypt. Egypt. J. Agron, 14(1-2): Abou El-Nour, E.A.A. and A.A. Abdel-Maguid, Foliar feeding of NPK as partial substitution of soil applied fertilizers for improving corn growth and decrease pollution. Al-Azhar J. Agric. Res., 38: Afifi, M.H.M., F. Manal, Mohamed.and S.H.A. Shaaban, Yield and nutrient uptake of some faba bean varieties grown in newly cultivated soil as affected by foliar application of of humic acid. J. of Plant Production, Mansoura Univ., 1(1): Alison, L.E and C.D. Moodle, Carbonate. In: C. A. Black (ed.), "Methods of Soil Analysis". Amer. Soc. Agron. Inc., Madison, Wisc. USA, pp: Ankerman, D. and L. Large, Soil and plant analysis. A&L Agric. Lab. Inc. New York, Brar, M.S. and A.S. Brar., Foliar nutrition as a supplement to soil fertilizer application to increase yield of upland cotton (Gossypium hirsutum ). Indian Journal of Agricultural Sciences, 74(8): Bouyoucos, H.H., A recalibration of the hydrometer for making mechanical analysis of soil. Agron. J., 43: Chapman, H.D. and P.F. Pratt, "Methods of analysis for soils, plants and waters", Priced Publication Division of Agricultural Sciences, Univ. of California, USA. Preparation of soil sample, p.5, P vanadate method, pp , and PH and EC, pp: El-Kholy, M.E., Response of some white and yellow maize varieties to nitrogen fertilization. M. Sc. Thesis, Agron. Dept. Fac. Agric. AinShams Univ. El-Fouly, M.M. and A.A. El-Sayed, Nitrogen balance in some some major field crops in Egypt. Proc. Seminar Production and use of Chemical Fertilizers and Environment Eds. El-Fouly and Abdalla,Cairo, 17-21: 1994: El-Fouly, M.M. and A.F.A. Fawzi, Higher and better yields with less environmental pollution in Egypt through balanced fertilizer use: Fertilizer Research, 43: 1-4. El-Kramany, M.F. and E. Mirvat. Gobarah., Response of faba bean (vicia faba L.) to N- slow release fertilizer and urea late foliar application in sandy soil. Egyptian J. agric. Res., 2(1): Agricultural and Biological Research Division, National Research Centre. Dokki-Giza, Egypt. El-Kramany, M.F., H. Magda, Mohamed and O.A. Nofal, Effect of late foliar application with urea and potassium fertilization on yield components and chemical composition of two mungbean varieties Egypt J. Appl. Sci., 18(12): Gooding, M.J. and W.P. Davies, Foliar urea Fertilization of Cereals: a Review Fertilizer Research Mengel, K and E.A. Kirkby, Principles of Plant Nutrition, 4 th Edition, International Potash Institute, Bern Switzerland, Isaac, R.A. and W.C. Johnson, Methodology for the Analysis of soil, Plant,Feed, Water and FertilizerSamples California Fertilizer Association (CFA). Organic matter determination in soils, pp: Jackson, M.L., Soil Chemical Analysis Prentice Hall of India Private limited, New Delhi, India. pp:

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