Abstract
Based on experiments conducted during 1988–2009 on rainfed pearl millet/sorghum with 9 treatments in Vertisols, an efficient treatment for sustainable productivity is identified. Twenty kg of nitrogen (N) from farmyard manure (FYM) + 20 kg N (urea) + 10 kg phosphorus (P) ha−1 in pearl millet and 40 kg N (urea) + 20 kg P + 25 kg zinc sulfate (ZnSO4) ha−1 in sorghum gave maximum yield and rainwater-use efficiency, whereas 20 kg N (FYM) + 20 kg (urea) + 10 kg P ha−1 in pearl millet and 40 kg (urea) + 20 kg P ha−1 in sorghum and gave maximum soil N, P, and potassium (K) over years. The regression model of 20 kg N (crop residue) + 20 kg N (urea) + 10 kg P ha−1 gave maximum R2 for predicting sorghum equivalent yield separately through precipitation and soil variables, whereas 20 kg N (FYM) + 20 kg N (urea) + 10 kg P ha−1 gave maximum R2 under combined model of both variables. Treatment of 20 kg N (FYM) + 20 kg N (urea) + 10 kg P ha−1 was superior for attaining maximum sorghum equivalent yield of 1062 kg ha−1, net returns of Rs. 4805 ha−1, benefit/cost (BC) ratio of 1.50, and 127 kg ha−1 of soil N, 10.3 kg ha−1 of soil P, and 386 kg ha−1 of soil K over years.
Acknowledgments
The authors gratefully acknowledge the contribution of all the scientists who were associated with the long-term study in this project.
Funding
Seventy-five percent of the funding for this long-term research was provided by ICAR through the All-India Coordinated Research Project for Dryland Agriculture, Central Research Institute for Dryland Agriculture, Hyderabad, and the remaining funding was provided by Tamil Nadu Agricultural University, Coimbatore.
Notes
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