Book of Extended summaries ISDA

International Conference on Reimagining Rainfed Agro-ecosystems: Challenges & Opportunities
during 22-24, December 2022 at ICAR-CRIDA, Hyderabad
The correlation between yield and N-dose was significant for both rice and wheat (data not
presented). The yield increase for each kg of N was 19.25 and 4.88 kg for maize and rice,
respectively. A quadratic function was also fitted with the yield and N- dose and data and the
most profitable fertilizer dose was worked out as 211 and 159 kg N ha -1 for maize and rice,
respectively. An N dose of 200 kg ha -1 registered the highest agronomic efficiency (AE) for
maize while the same was 80 kg N ha -1 for rice. However, for partial factor productivity (PFP)
irrespective of crops, the highest value was noted for 40 kg N ha -1 while the lowest was for 240
kg N ha -1 .
Mean values followed by different small letters within N-dose or genotypes are significantly
different at P < 0.05 by Duncan’s Multiple Range Test.The grain N content of rice was
significantly affected by different amounts of nitrogen and genotypes. The lowest grain N
content was 1.09% for 0 kg N ha -1 while the highest was 1.49 for 240 kg N ha -1 . Among rice
genotypes, the highest N content of grain was observed for Swarna Samridhi (1.39%) and the
lowest was for RCPR 58 (1.24%).
Conclusions
Higher production of high-quality grain (higher grain N content) requires higher application of
fertilizer and greater uptake by crops.The maize was more responsive to fertilizer N than rice.
Hence, fertilizer level must be optimized to balance grain yield, grain N content and profit.
References
Galloway, J. N., Townsend, A. R., Erisman, J. W., Bekunda, M., Cai, Z., Freney, J. R. and
Sutton, M. A. 2008. Transformation of the nitrogen cycle: recent trends, questions, and
potential solutions. Science, 320(5878): 889 – 892.
Zhang, X., Davidson, E. A., Mauzerall, D. L., Searchinger, T. D., Dumas, P. and Shen, Y. 2015.
Managing nitrogen for sustainable development. Nature. 528(7580): 51 – 59.
472 | Page Sustainable soil management for resilient rainfed agro-ecosystem: conservation agriculture, organic farming, INM, soilmicroorganisms-plant
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