IMPACT OF VARIOUS NITROGEN AND POTASSIUM LEVELS AND APPLICATION METHODS ON GRAIN YIELD AND YIELD ATTRIBUTES OF WHEAT

The impact of nitrogen (N) and potash (K) levels and application methods on yield and yield attributes of wheat was investigated in experiments conducted at the University of Agriculture, Peshawar during Rabi 2010-11 and 2011- 12. The experiments were laid out in RCB design with splits plot arrangements applying application methods to main and combinations of N and K to sub-plots using three replications. A subplot size of 1.8 m × 5 m having 6 rows 30 cm apart and 5 m long was used. Four levels of N (90, 120, 150 and 180 kg ha^-1), three levels of K (30, 60 and 90 kg ha^-1) and four application methods (soil application, 95% soil + 5% foliar application, 90% soil + 10% foliar application and 85% soil + 15% foliar application) were applied. Foliar spray was started at tillering and completed within two weeks. Pre-sowing soil tests were carried out for the N, K, organic matter and soil pH. Foliar K was applied in the form of Solo Potash (50% K2O) using 0.57 Molar K solutions. A basal dose of P was applied @ 90 kg P2O5 ha^-1. Wheat cultivar “SIRAN-2010” was used in the experiment. It was observed that as an average of the two years, grain yield increased by 7.6% with 15% foliar application of nutrients as compared with soil applied. Yield components improved with increase in N and K levels. Based on the average of the two years, N @ 180 kg ha^-1 in interaction with K @ 90 kg ha^-1 enhanced grain yield by (47.4%), biological yield (28.5%), 1000 grain weight (29.2%), and grains spike^-1 (24.6%) as compared with control. On the basis of these results, it is recommended that N @ 180 and K @ 90 kg ha^-1 in combination should be applied for higher grain yield of wheat. Nitrogen @ 180 kg ha^-1 with 10% foliar application are recommended for higher grain yield of wheat.