Energy input and yield relations for wheat in different agro-climatic zones of the Punjab

Modern farming has become very energy intensive. Nowadays cropping pattern, farm activities and level of technology define the energy requirements. Energy needs are not only increasing in the agricultural sector, but in all sectors involving human activities. There is a great need to balance the use and availability of energy especially in the agricultural sector, in such a manner, so as not to affect the production adversely. Realising the implications of energy use, a study was carried out on the energy consumption patterns, in different agroclimatic zones, for the wheat crop in the state of Punjab in India. Mathematical relations were fitted to the yield and total energy input. An attempt was also made to optimise the energy inputs using a frontier production function for different agro-climatic zones. Under the present conditions, where irrigation is not assured, there is not much scope for increasing the yield of wheat in zone 1. However a 5.4% increase in yield is expected in zone 2 by providing 26.9% additional energy input through irrigation and the use of a fertiliser. The yield can be increased by 3.2% to 4049 kg/ha from 3922 kg/ha by putting 18.6% more energy input in zone 3. Yield can be increased to 4934 kg/ha (an increase of 13.7%) by an additional energy input of 28.5% in zone 4, On the other hand, the additional energy input of 29.6% gives only 1.3% increase in yield in zone 5. In most cases, the proper placements of seed, irrigation and fertiliser played significant roles in increasing the productivity in addition to some unknown parameters such as soil type and weather conditions. (C) 1999 Elsevier Science Ltd. All rights reserved.