Physiological Behaviour and Yield Evaluation of Agronomic Crops Under Agri-horti-silviculture System

An agri-horti-silvicultural model involving poplar (Populus deltoides Bartr. Ex Marsh.) as timber tree component, fruit trees and agronomic crops viz, turmeric (Curcuma longa L.) and moong (Vigna radiata L.) were evaluated for yield. Net photosynthesis, stomatal conductance and transpiration in both crops were higher in open areas than in shaded ones. Agronomic crops showed initially better performance under partial shade in yield and yield contributing parameters, and decreased as poplar canopy advanced in age. Changes in these parameters showed inverse relationship with canopy age and vice versa with more yield reduction under fifth year old canopy followed by preceding years and control. The results of studies on the micro-climatic interaction and resultant effect on physiology, yield and economics of agronomic crops under poplar tree canopy are presented in this paper. The transpiration (E) rate of crops was lowest under shade conditions irrespective of the crop used in the experiment leading to more water use efficiency in the shade conditions than in open. There was gradual reduction in crop yield with advancement of age but the economic benefits of intercropping were two to three times higher than traditional crop rotation. It is suggested that to minimize resource competition and improve physiological processes of crops, canopy management is essential to ensure better yield under poplar-based agri-horti-silvicultural system.