In India the benefits of foliar-applied K and N sources were examined in 4 years of field experimentation. The foliar K and N sources were applied in addition to the recommended rates of basal N and P of 75 kg N plus 30 kg P2O5/ha (and 0 kg K2O/ha). Three mid-season foliar KNO3 applications, spaced at weekly intervals, were applied. The experimental plots were unable to meet the high daily N and K requirements during flowering and boll development, the foliar products were all effective but KNO3 gave the highest yield increase of 36% (Table 1).
Table 1. The effect of foliar sprays on the average seed cotton yield in 4 years compared to control treatment.
Brar, M.S. and K.N. Tiwari. 2004. Boosting Seed Cotton Yields in Punjab with Potassium: A Review. Better Crops/Vol. 88 (No. 3): 28-31.