Optimizing rates and application time of potassium fertilizer for improving growth, grain nutrients content and yield of wheat crop

Nutrient management is a key component of best agronomic practices for optimal crop production. The continuous use of high yielding genotypes and exhaustive cropping systems has resulted in potassium deficiency. Furthermore, the imbalanced use of nutrients, particularly potassium (K), has resulted in persistent depletion from agricultural soils. To address this issue, a field experiment was conducted to determine the influence of different potassium levels under a split application on yield and yield attributes of wheat crops. The experiment was laid out in a randomized complete block design replicated four times. Five K levels (0, 60, 80, 100 and 120 kg ha −1 ) and different K application timings (whole dose (Basal) at sowing, equal doses at sowing+ 30 DAS, half dose at sowing+ equal doses at 30 +60 DAS and equal doses at sowing+30+60+ 90 DAS). The findings of the study revealed that potassium levels and their application times substantially influenced yield and yield components of wheat. The application of K at 120 kg ha −1 delayed anthesis and maturity and enhanced chlorophyll content (53), tillers m −2 (293.4 m −2 ) and increased plant height (97.1cm). The application of K 80 kg ha −1 significantly increased grain protein, nitrogen, phosphorus and potassium content which resulted in a higher (4227 kg ha −1 ) grain yield. In the case of K timings application, the higher grain yield (3758 kg ha −1 ) was achieved when K was applied one time at sowing time. It is concluded that K at the rate of 80 kg ha −1 should be applied in full at sowing for achieving higher wheat production.