Morpho-Physiological Changes in Wheat (Triticum Aestivum) Associated with Different Cropping Sequence and Nutrient Management Practices

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1 Morpho-Physiological Changes in Wheat (Triticum Aestivum) Associated with Different Cropping Sequence and Nutrient Management Practices Rajeew Kumar* 1, D.S. Pandey 2, V.P Singh 3, Aniket Kalhapure 4 Department of Agronomy; College of Agriculture, G.B. Pant University of Agriculture & Technology, Pantnagar (India) * 1 shuklarajeew@gmail.com; 2 dspandey@gmail.com; 3 singhvijaypal100@gmail.com; 4 aniketmpkv@gmail.com Abstract-Food pressure and land limitations for crop cultivation compels us to think about vertical expansion of crops to feed earth dwellers. Considering this, two years of field experiments were conducted in a split plot design at the Norman E. Borlague Crop Research Center of G. B. Pant University of Agriculture and Technology, Pantnagar, India, to find out the effect of cropping sequences and nutrient management on the performance of wheat crop. The experimental plot was silty, clay loam in texture, medium in organic carbon and available phosphorus and low in nitrogen. However, the ph was slightly alkaline. Two cropping sequences viz. Rice-wheat and rice-lahi-wheat were kept in the main plot, and nutrient management practices were kept in sub plots. Seven nutrient management practices, i.e. Control, 10 t/ha, Green manuring before rice, Rice straw incorporated without starter dose of N, and Rice straw incorporated with starter dose of (20 kg N/ha were applied in wheat. RDF, i.e 150:60:40 kg NPK/ha, was applied in all the treatments. Comparative results revealed that morphological characteristics viz plant height at maturity, numbers of tillers, ear bearing shoots, leaf area index, and leaf nitrogen content and physiological parameters viz. chlorophyll content, rate of photosynthesis and nitrate reductase were significantly higher in rice-wheat cropping sequences than rice lahi wheat cropping sequences. Similarly, yield and yield contributing characteristics and economic returns were significantly higher in rice-wheat cropping sequences than rice-lahi-wheat. Among nutrient management practices, superior morphological parameters, physiological parameters, yield attributing characteristics, grain yield and economic return were noticed in the plots that received either FYM or crop residue with a starter dose than the other nutrient management practices. Results suggest that the rice- wheat cropping system was a better cropping system than the rice-lahi-wheat system and RDF, and, with the addition of FYM or crop residue, can be helpful to increase morpho-physiological determinants in wheat and thereby increase yield and profit. Keywords- Crop residue; FYM; Green manure; RDF; Toria I. INTRODUCTION The Indo-gangetic plain (IGP) is now the bread basket for South Asians. Rice and wheat, the major cereal crops of this region, are grown in rotation on almost 12 Mha of land[1]. Continuous adoption of rice wheat sequences has led to the problem of specific weeds, reduced soil fertility in specific root zones, and, ultimately, declining efficiency and productivity of the system. However, farmers of this region want to further intensify this sequence to raise their income and productivity. They are not aware of the type and nature of crop that would be fitted into their own cropping sequence. Oilseed s cultivation in between rice and wheat is receiving more attention to fetch higher prices and benefits [2], but they are not always in positive side of economics by fitting these crops with conventional methods. Even information on compatibility of Brassica within the rice wheat system is still lacking [3]. Hence, the need of establishing economically efficient cropping system (with sequential cropping) is remarkable, considering the local climate and available resources. Morphological and physiological changes in wheat have a special role in determining the wheat yield and influencing input applications at certain stages of plant development [4].Therefore, a sound understanding of plant growth and development is an essential element of efficient and economic wheat management systems [5]. Nutrients are an important input to maximize wheat yield and, in general, rice-wheat crop sequence annually removes more than 690 kg/ha of NPK, and 0.7 kg/ha Zn, 2.6 kg/ha Fe and 3.9kg/ha Mn resulted in productivity being threatened in the long term, and farmers have to use increased fertilizer doses to realize the same yield level which they had previously reaped [6]. Simultaneously, this also led to development of many problems related to soil fertility, soil health and crop productivity. Current generalized recommendations practice of NPK are also responsible for soil fatigue and decreased nutrient efficiency, and thus need upward refinement and proper balance among the required nutrients, which is essential for high agricultural productivity and soil health [7]. Integrated use of organic manures and chemical fertilizers has been found to be promising in arresting declines in productivity through the correction of marginal deficiencies of some secondary and micronutrient elements and its beneficial influence on the physical and biological properties of the soil [8] and can be a practice for sustaining economically viable crop production with minimal environmental pollution. Application of green manure, residue recycling, and/or FYM in the system can minimize the yield penalty due to intensification and also favor the diversification of the system. However, at present, adequate quantities of organic manures like FYM and compost are difficult to obtain due to mechanized agriculture. Therefore, inclusion of short duration oil seed crop in rice-wheat systems has been shown to augment productivity of the system and maintain good soil health [9]. Incorporation of straw results in the recycling of a sizable amount of plant nutrients. For example, rice straw

2 accounts for about 35-40% N, 12-17% of P and 80-90% of K removal by a rice crop [10]. The sole recycling/incorporation of cereal straw, which is available in situ, is not possible due to two main reasons: (i) in many parts of the Indo Gangetic plains, in the Terai of Nepal and in China, straw is used as feeding for animals, fuel and other uses, and (ii) because of the wide C:N ratio (70 or above), it can result in a temporary immobilisation of native soil and applied mineral N [11]. Some researchers have reported increased yield of rice and/or wheat by the incorporation of wheat/rice residue[12], while others have failed to do so[13]. Hence, there is an urgent need to develop a suitable technology to use crop residues in wheat. Mixing the crop residues of cereals with well-decomposed farmyard manure/compost/vermicompost or crop residue of legumes reduces the C:N ratio so as to overcome the adverse effects of N immobilisation. Hence, in the present investigation, an effort has been taken to delineate the morpho-physiological characteristics of wheat in relation to cropping sequences and nutrient management practices. II. MATERIALS AND METHODS Field experimentations were carried out for two years ( and ) at the NEB Crop Research Centre of G.B. Pant University of Agriculture and Technology, Pantnagar, India, situated at N latitude and E longitude. The soil of the experimental site was silty clay loam in texture with ph- 7.2, organic carbon 0.81%, total nitrogen kg/ha, available nitrogen kg/ha, available phosphorus 19.7 kg/ha and available potassium kg/ha. The experiment was laid out in a spit plot design with four replications. The main plots contained two cropping sequences viz. Rice- Wheat cropping sequences and Rice- Mustard (Brassica campestris L. var. Toria)- Wheat sequence. The sub plot treatment contained five nutrient management practices, viz. control, 10 t/ha, Green manuring (Sesbania aculeata) before rice, Straw incorporation without starter dose of N and Straw incorporation with starter 20 kg N/ha. The application of organic sources and their contributions to the soil nutrient supply is given in Table 1, and the details of the crop are given in Table 2. The recommended dose of fertilizers, which was 150 kg N, 60 kg P 2 O 5 and 40 kg K 2 O per hectare, were applied in the field uniformly for each rice and wheat crop. However, 90:40:20 kg NPK/ha was applied in toria. Urea, diammonium phosphate and muriate of potash were used as sources of nitrogen, phosphorus and potassium, respectively. Full doses of FYM, phosphorus and potassium and half doses of nitrogen were applied at the time of sowing. The remaining half dose of nitrogen was top dressed after the first irrigation. Crop residue was retained after the harvesting of rice crop. The observations were taken by following standard procedures, and the data obtained was subjected to standard statistical analysis. TABLE 1 PARTICULARS ABOUT FYM, DHAINCHA (GM) AND RICE STRAW Organic source Mean data of two years N% P% K% O.C.% C:N ratio Fresh biomass (t/ha) Dry Biomass (t/ha) FYM : Dhaincha : Rice straw : TABLE 2 THE DETAILS OF CROPS Crop Variety Seed rate ( Kg ha ) Row spacing ( Cm ) Recommended dose of fertilizer (RDF)Kg/ha N P 2O 5 K 2O Rice Pant Dhan Wheat PBW Lahi (Brassica compestris var toria) PT Dhaincha Pant Ses *Wheat was sown on and in rice wheat cropping sequence and and in rice lahi wheat system. A. Morphological Characteristics III. RESULTS AND DISCUSSION Morphological parameters like plant height, numbers of tillers, ear-bearing shoots and leaf area index were significantly influenced by the cropping sequences and nutrient management practices (Table 3). Rice- wheat cropping sequences produced significantly higher value of morphological characteristics than rice-lahi-wheat sequences. The differences was 25.18% greater in plant height, 0.78% higher in drymatter, 21.48% higher in tillers, 17.65% higher in ear bearing shoots and 25.23% higher in

3 leaf area index. Lower morphological characteristics occurred in rice-lahi-wheat systems because of late-sown wheat exposed to high temperature resulted in completion of their vegetative stages in a smaller span of time [14]. Among the nutrient management practices, rice straw incorporation with a starter dose of 20 kg N/ha gave the tallest plants, but other treatments were at par with this, except rice straw incorporation without a starter dose of N. 10 t/ha FYM in wheat and rice straw incorporated with a starter dose of 20 kg N/ha gave significantly more dry matter, tillers and ear bearing shoots and leaf area index than the other treatments. FYM produced taller plants and higher vegetative growth because of the balanced nutrient supply throughout the cropping season, which helped in better vegetative growth. Similar effects of cropping sequences and nutrient levels on morphological parameters were also reported by Jaga and Upadhyay [15]. TABLE 3 EFFECT OF CROPPING SEQUENCES AND NUTRIENT MANAGEMENT ON MORPHOLOGICAL PARAMETERS OF WHEAT CROP (POOLED DATA OF TWO YEARS) Treatment Plant height (cm) Dry matter at harvest (g/m 2 ) Tillers at 90 DAS Ear bearing shoots Leaf Area Index at heading stage Cropping sequence Rice- Wheat Rice- lahi- Wheat LSD (0.05) Nutrient Management Control t/ha Green manuring before rice Rice straw + without starter dose of N Rice straw + starter 20 kg N/ha LSD (0.05) B. Physiological Parameters Physiological parameters like leaf Nitrogen content, chlorophyll content (SPAD reading), rate of photosynthesis (µ moles cm -2- s -1 ) and nitrate reductase activity (µ moles/g fresh weight/hr.) were significantly influenced by cropping sequence and nutrient management (Table 4). Higher values of these parameters were noticed in Rice-Wheat cropping sequences than in the Rice-lahi-Wheat sequence (Fig 1). Application of 10 t/ha FYM before wheat resulted in a significantly higher amount of chlorophyll content (in terms of SPAD reading) and Nitrate reductase activity (µ moles/g fresh weight/hr.) over the rest of the treatments. However, it was found to be on par with rice straw incorporation with a starter dose of 20 kg N/ha. Chlorophyll content was higher in Rice-Wheat sequence possibly due to atmospheric temperature and plant age during cropping season, which played an important role in the synthesis of chlorophyll. Nitrate reductase activity in wheat was higher in Rice-Wheat cropping sequences, because this system might produce more amino acid and finally convert it into the protein [16]. A similar effect of nutrients levels on nitrate reductase activities was also reported by Mishra [17]. Photosynthesis processes depend on chlorophyll content, providing metabolic energy for crop growth and development. The effect of nutrient levels is explained clearly by the report of Lawlor et al. [18]

4 Leaf N content 30 Chlorophyll content 20 Rate of Photosynthesis 10 0 Rice- Wheat Rice- lahi- Wheat Nitrate reductase activity Fig. 1 Effect of cropping sequence on physiological characteristics in wheat TABLE 4 EFFECT OF CROPPING SEQUENCES AND NUTRIENT MANAGEMENT ON PHYSIOLOGICAL PARAMETERS OF WHEAT CROP (POOLED DATA OF TWO YEARS) Treatment Leaf N content at 60 DAS (% of dry matter) Chlorophyll content (SPAD reading) at 10 DAH* Rate of Photosynthesis (µ moles cm -2- s -1 ) at 10 DAH* Nitrate reductase activity (µ moles/g fresh weight/hr.) at 10 DAA** Cropping sequence Rice- Wheat Rice- lahi- Wheat LSD (0.05) Nutrient Management Control t/ha Green manuring before rice Rice straw + without starter dose of N Rice straw + starter 20 kg N/ha LSD (0.05) (* Days after heading ** Days after anthesis) C. Yield Contributing Characteristics and Yield Yield contributing characteristics were significantly affected by cropping sequences (Table 5). Rice-wheat cropping sequences produced higher spike lengths (15.5%), fertile spikelets per spike (14.9%), grains per spike (38.3 %), grain weight per spike (79.6) and 1000 grain weight (18.1%) than the rice-lahi-wheat sequence. However, nutrient levels showed a significant effect only on grains per spike, grain weight per spike and 1000 grain weight. The yield contributing characteristics obtained with application of 10 t/ha FYM before wheat and rice straw incorporation with a starter dose of 20 kg N/ha were statistically similar, but significantly higher than the control and without the starter dose. Grain yield of wheat was significantly higher in Rice-wheat cropping sequences, which produced 47.6% more yield than the Rice-lahi-wheat sequence (Table 5). Application of 10 t/ha FYM before wheat and rice straw incorporation with a starter dose of 20 kg N/ha produced significantly higher grain yield over the rest of the nutrient management practices. The addition of FYM and Crop residue with a starter dose gave higher yield contributing characteristics and, ultimately, yield. The reason behind this is the availability of nutrients from FYM for longer periods to provide 30% of nitrogen, 60-70% phosphorus and 70% of potassium to be available to the first crop [19]. Similar to this, the starter dose activated the flora and fauna in soils, which are responsible for decomposition and release of nutrients. In the present investigation, FYM was evolved as a superior amendment, but the rice straw with starter doses can be used under constraint availability of FYM. Similar observations were recorded by Katyal et al [20]

5 TABLE 5 EFFECT OF CROPPING SEQUENCES AND NUTRIENT MANAGEMENT ON YIELD CONTRIBUTING CHARACTERS OF WHEAT CROP (POOLED DATA OF TWO YEARS) Treatment Spike length (cm) No of fertile spikelets /spike Number of grain / spike Grain weight/spike (g) 1000 grain weight (g) Grain yield (q/ha) Cropping sequence Rice- Wheat Rice- lahi- Wheat LSD (0.05) Nutrient Management Control t/ha Green manuring before rice Rice straw + without starter dose of N Rice straw + starter 20 kg N/ha LSD (0.05) NS NS IV. CONCLUSION From the present investigation, it can be concluded that the rice-wheat cropping sequence is a better cropping system in terms of yield and benefits. The application of 10 t/ha FYM before wheat gives statistically similar results on grain yield obtained to rice straw incorporation with a starter dose of 20 kg N/ha. Thus, it can be that in the case of limited FYM availability, residue of the previous rice crop will be viable option for higher wheat grain production. REFERENCES [1] P.K. Aggarwal, P.K. Joshib, J.S.I. Ingramc, and A.D. Gupta, Adapting food systems of the Indo-Gangetic plains to global environmental change: key information needs to improve policy formulation, Envrtl Sci. & Policy, vol. 7, pp , [2] A.K. Padhi and R.K. Panigrahi, Effect of intercrop and crop geometry on productivity, economics, energetics and soil fertility status of maize (Zea mays)-based inter-cropping systems, Ind. J. Agron., vol. 51(3), pp , [3] R.K. Srivastava, J.S. Bohra, and R.K. Singh, Yield advantage and reciprocity functions of wheat (Triticum aestivum) + Indian mustard (Brassica juncea) inter-cropping under varying row ratio, variety and fertility level, Ind. J. Agric. Sci., vol. 77(3), pp , [4] H.J. Braun, G. Atlin, and T. Payne, Multi-location testing as a tool to identify plant response to global climate change, In MP Reynolds, ed., Climate Change and Crop Production, CABI, Oxfordshire, UK, pp , [5] J. Herbek and C. Lee, A Comprehensive Guide to Wheat Management in Kentucky, U.S. Department of Agriculture, M. Scott Smith, Director, Cooperative Extension Service, University of Kentucky College of Agriculture, Lexington, and Kentucky State University, Frankfort, [6] M.J. Akhtar, H.N. Asghar, K. Shahzad, and M. Arshad, Role of plant growth promoting rhizobacteria applied in combination with compost and mineral fertilizers to improve growth and yield of wheat (Triticum aestivum L.), Pak. J. Bot., vol. 41, pp , Jan [7] M.S. Aulakh and C.A. Grant, Integrated Nutrient Management for Sustainable Crop Production, (The Haworth Press, Taylor and Francis Group: New York). [8] Shah, Zahir, Ahmad, Rashid, Hidayat Ur Rahman, A. Latif, and A. Shah, Rice and wheat yields in relation to biomass of green manure legumes, Sarhad J. Agric., vol. 27 (1), pp , [9] Z. Fang, S.H. Lu, and F.S. Zhang, A study of the differences of wheat and oilseed rape in tolerance to Mn deficiency, Field. J. Hebei Agril. Uni., China. vol. 23 (3), pp. 1-4, [10] S.K. Sharma and S.N. Sharma, Integrated nutrient management for sustainability of rice-wheat cropping system, Ind. J. Agric. Sci., vol. 72, pp , [11] Aulakh, M.S., Khera, T.S., Doran, J.W., Singh, K. and Singh, B., Yields and nitrogen dynamics in a rice wheat system using green manure and inorganic fertilizer, Soil Sci. Soc. Am. J., vol. 64, pp , [12] R. Prasad, B. Gangaiah and K.C. Aipe, Effect of crop residue management in a rice wheat cropping system on growth and yield of crops and on soil fertility, Experimental Agric., vol. 35, pp , [13] S.N. Sharma, Effect of organic farming on productivity and soil fertility under rice-wheat cropping system, Abstract. 2nd Intl. Rice Congress Oct. 9-13, p. 556, [14] Khalid Nawab, Amanullah, and Asad Ali, Response of Wheat to Farm Yard Manure, Potassium and Zinc under Rainfed Cropping Patterns, Middle-East J. Sci. Res., vol. 1 (1), pp , [15] P.K. Jaga and V.B. Upadhya, Effect of integrated nutrient management in wheat: A review, Innovare J. Agric. Sci., vol. 1(1), pp. 1-3, [16] S. Mahapatra, Production, profit and Energy potential of wheat (Triticum aestivum L) through integrated nutrient management in wheat based cropping systems, Ph.D Agronomy thesis submitted to G.B.Pant University of Agriculture & Technology, Pantnagar, 2003 [17] V.K. Mishra, Studies on physiology of heat tolerance in different genotypes of wheat, Ph.D. Agronomy thesis submitted to G.B.Pant University of Agriculture & Technology, Pantnagar,

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