Impact of manipulating poplar canopy on micro-environment and marigold yield under agri-silviculture system

Populus deltoides, a fast growing tree species attains, a crown closure within 2–3 years and crown size increases with advancement in the age. The manipulation of canopy of poplar plays an important role in changing the microclimatic conditions such as humidity, temperature, light intensity and photosynthetically active radiation (PAR). The changes in microclimatic conditions in poplar plantation affect the physiological processes of the intercrops. To regulate the shade, it is essential to prune the trees to increase the light penetration between trees which improves intercrop yield. In the study, highest temperature was recorded in open and lowest under canopy of un-pruned poplar, and higher relative humidity was recorded under canopy. Maximum growth of Tagetes patula var. Jafri was observed in open, while among pruning treatments, it was found maximum under 75% pruning treatment. Fresh flower yield was significantly higher in pure crop. In agri-silviculture system, among pruning treatments, fresh flower yield was highest in 75% pruning with topping (12.96 q/ha) and it decreased with the decrease in pruning intensity. Pruning treatments have significant effect on DBH of poplar. Maximum current annual increment (CAI) in DBH was recorded in 50% pruning with topping (2.62 cm) as compared to other treatments.