Major nutrients supply in legume crops under stress environments

Abstract

Legumes are used as food crops by human beings world-over. They are rich in protein and are considered as meat for common people in the third world countries. These crops are severely affected by water stress; however, the literature shows that by proper nutrient management economical legume crop yields can be obtained from drought prone lands. This chapter includes the recent information regarding the effect of nutrients, particularly of major nutrients such as N, K, P, Ca, Mg and S on improvement in drought tolerance and productivity for sustainable agriculture in drought-hit areas. Although legumes have an inherent ability to fix atmospheric N, it is severely reduced under water stress conditions. Therefore, a limited supply of N is recommended as a starter dose for legumes. K enhances the drought tolerance potential and plant productivity by regulating photosynthesis and improving water relations. P deficiency is very common in legume crops, which becomes severe due to moisture stress. P application generally improves seed yield, protein contents and stress tolerance in legume crops under water stress conditions. Similarly, application of sulphur (S) is effective in increasing number of branches, pods, seeds per pod and 1,000-seed weight in legumes under limited water availability conditions. Calcium (Ca) amendment reduces the death rate of apical meristems, root tips and buds which occurs due to water shortage. It improves the plant size, vegetative growth and crop yield of legumes under water stress conditions. Application of Mg is recommended by many workers to reduce yield losses and improve drought tolerance in legume plants. So, proper management of nutrients is necessary to achieve economical yield from legume crops on cultivation under low soil moisture availability conditions.