LAUSR

Pearl-millet yield in arid zone vary from being < 9 to > 4 times of long-term average yield due to variations in rainfall. Thus, it is difficult to assess sustainable yield levels and manure and/or urea needed to sustain them. A long-term field experiment (1993–2013) was conducted and results were statistically inferred for above purpose. 80% variation in annual grain yield could statistically be attributed to rainfall and 10% to manure/urea and even this response was not significant in all the years. 20 kg urea-N significantly increased grain yield in five out of 21 years whereas 5 ton manure + 40 kg urea-N increased it in 17 years. Grain yield of pearl-millet cultivated without any manure/urea-N decreased at the rate of 44.9 kg ha−1 year−1. 20 and 40 kg urea-N ha−1 and 2.5 ton manure retarded this decline however 2.5 tons of manure + 20 kg urea-N, reversed this trend. 5.0 ton manure + 40 kg urea-N ha−1 increased grain yield by 33.3 kg ha−1 year−1 and maximum grain production over 21 years was also recorded in this treatment. 2.5 ton manure + 20 kg urea-N ha−1 was selected to provide highest food security. This is also supported by sustainable yield index.