Abstract
Soil degradation in the semi-arid tropics (SAT) is mainly responsible for low crop and water productivity. In Madhya Pradesh and Rajasthan states in India, the soil analyses of farmers’ fields revealed widespread deficiencies of S (9–96%), B (17–100%) and Zn (22–97%) along with that of P (25–92%). Soil organic C was deficient in 7–84% fields indicating specifically N deficiencies and poor soil health in general. During on-farm evaluations in rainy seasons 2010 and 2011, the soil test based addition of deficient nutrient fertilizers as balanced nutrition (BN) increased crop yields by 6–40% (benefit to cost ratios of 0.81–4.28) through enhanced rainwater use efficiency. The integrated nutrient management (INM), however, decreased the use of chemical fertilizers in BN by up to 50% through on-farm produced vermicompost and recorded yields at par or more than BN with far better benefit to cost ratios (2.26–10.2). Soybean grain S and Zn contents improved with INM. Applied S, B, Zn and vermicompost showed residual benefits as increased crop yields for succeeding three seasons. Hence, results showed INM/BN was economically beneficial for producing more food, while leading to resilience building of SAT production systems.
Acknowledgements
The support from Sir Dorabji Tata Trust, Mumbai, India for undertaking the presented work is gratefully acknowledged. Authors also acknowledge help from NGO's BAIF, DEEP, BYPASS and CARD for collecting data from the farmers and Satish Gahukar for his help in handling samples and data. Authors also sincerely thank G. Pardhasaradhi for plant chemical analysis, Dr. A.V.R. Kesava Rao and K. Srinivas for providing rainfall data.