Microclimatic conditions under different shade trees and their effect on tea leaf growth rate

Micrometeorological variations within the tea canopy influence the tea yield to a considerable extent. An experiment was conducted at the Experimental Garden of Assam Agricultural University Jorhat, Assam during 2022 - 2024 to examine the effects of five shade tree species viz., Sao koroi (Albiziachinensis), Xil koroi (Albizia odoratissima), Neem (Azadirachta indica), Amla (Phyllanthus emblica), and Areca nut (Areca catechu) on micrometeorological parameters such as air temperature (AT), canopy temperature (CT), relative humidity (RH), photosynthetically active radiation (PAR), soil moisture (SM), soil temperature (ST), and rainfall (RF) affecting leaf growth and yield. The highest green leaf growth rate (GLGR) occurred during the monsoon season (41.7 ± 12.1 kgha-1day-1), with the highest GLGR (41.8 ± 13.1 kgha-1day-1) achieved under Neem shade. GLGR has a significant positive correlation with most of the parameters except rainfall which showed no significant influence on GLGR. Regression analysis revealed that rainfall negatively impacted GLGR. This study highlights the role of shade trees in mitigating stress and optimizing growth conditions, providing insights into sustainable tea cultivation practices.