Foliage applied potassium improves stay green, photosynthesis and yield of maize ( Zea mays L . ) under rainfed condition

In rainfed agriculture, the optimum use of fertilizers could not be achieved due to moisture constraint. In such areas where agriculture is rainfall dependent, foliar application of nutrients is better option to optimize crop yield. Therefore, the present study was conducted to check the performance of maize varieties and assess the effect of foliage applied potassium (K) on the photosynthetic activity, stay green, grain yield and related attributes of maize under rainfed condition. Current study was carried out with the objective to find best adopted variety and K rate for increasing photosynthetic activity and grain yield in maize. The results showed that, foliar application of K (2%) improved stomatal conductance, photosynthetic rate and chlorophyll contents in maize variety Islamabad gold. It also improved grain size and 1000-grain weight which leads to 10% higher grain yield compared with control. However foliar application of 2% K as well as maize variety Islamabad gold should be further investigated under rainfed condition.