Effect of micronutrients (Zn,Cu and B) on photosynthetic and fruit yield attributes of citrus reticulata Blanco var. kinnow

In this investigation,influence of foliar application of micronutrients (zn,cu and b) was studied on the improvement in photosynthetic and fruit yield attributes of citrus (kinnow) plants. experiments were conducted in two districts of punjab (sargodha and toba tek singh),pakistan varying in soil properties and agro-climatic conditions. plants at both sites were subjected to foliar spray of three different levels (i.e. 0.1,0.2 and 0.3%) of each zn,cu and b at three different fruit developmental stages while macronutrients (npk) were applied at recommended rates as soil amendment. micronutrients (zn,cu and b) application caused a significant improvement in net photosynthetic rate (a),transpiration rate (e),stomatal conductance (gs),chlorophyll “a”,“b”,“total”,and caroteniods in both the citrus orchards. however,effect of micronutrients i.e. zn,cu and b was more pronounced at the levels of 0.3,0.1 and 0.2%,respectively. these levels of nutrients were also effective in improving fruit yield with better fruit quality. © 2015,pakistan botanical society. all rights reserved.