A Critical Review on Nitrogen Management in Speciality Corn under Pongamia + Maize Agri-silvi System

Intercropping of agricultural crops with woody species is an age-old practice in traditional farming systems in the tropics. Food production is the major aim of subsistence farmers with most of their farmland being allocated to food crops rather than to trees and shrubs. Due to increasing population and scarcity of productive lands that cannot sustain intensive exploitation, one method that has been proposed to enhance the sustainability of agricultural production is the growing of trees in association with crops. Alley cropping is an agroforestry system in which food crops are grown in alleys formed by hedge rows of trees or shrubs and these hedge rows are kept pruned during the rainy season. The hedge rows are usually cut to a height of about 2 m when crops are sown and kept pruned to reduce competition with crops. Work done on alley cropping in Pongamia pinnata was less in India and other countries. Hence literature pertaining to tree crop competition studies in agri-silvi system was presented in this chapter. Moreover, it was unable to get sizeable literature related to speciality corn. In view of the paucity of adequate literature related to speciality corn, few citations with respect to grain corn were also presented in brief to know the general scientific idea. The available literature related to the present study has been reviewed under the following heads. 1 Tree crop competition studies in agri-silviculture system. 2 Performance of arable crops in alley cropping system. 3 Performance of speciality corn under the influence of graded nitrogen levels. 4 Economic studies in agri-silviculture system.