Division of Horticulture and Fruit Technology, Indian Agricultural Research Institute, New Delhi-110012
The result of field studies suggest that the K content of sweet orange leaves may be increased markedly by using foliar applications of potassium nitrate solutions. Four potassium nitrate sprays at least were required to bring low levels to optimum concentrations in orange leaves. The total increase in leaf K content sampled on different days were maximum in 0.75 M and 1.00 M potassium nitrate treatments in Hamlin and Valencia during 1971 and 1972. The potassium nitrate sprays exerted a depressing effect on Ca and Mg contents of the leaves whereas the N and P concentrations were appreciably increased.
