Effect of Potassium Fertilization on Growth and Yield Attributes of Rice (Oryza sativa L.) Crop in an Inceptisol

A pot experiment was designed for two consecutive years of (2018 and 2019) to investigate the effect of optimal use of potassium fertilizer by applying at different rates 0, 10, 20, 30, 40, and 50 mg K kg-1 10 kg pot-1 soil. Rice cv. HUR-36 (Malaviya Dhan-36)] crop was transplanted by maintaining four seedlings in each pot and potassium fertilization effect on plant growth and yield attributes of rice was recorded. The experiment was carried out in completely randomized design (CRD) with seven treatments viz., T1: absolute control (0:0:0), T2: 60:30:0 mg kg-1, T3: 60:30:10 mg kg-1, T4: 60:30:20 mg kg-1, T5: 60:30:30 mg kg-1, T6: 60:30:40 mg kg-1 and T6: 60:30:50 mg kg-1 corresponding to 120, 60, 60 (N:P2O5: K2O) kg ha-1. The experiment was conducted in triplicate. The data pertaining to experiment revealed that plant height, effective no. of tillers, chlorophyll content and grain and straw yield were significantly increased as the scheduled rates of potassium fertilizer application increases. In treatment T5 receiving 60:30:30 mg kg-1, potassium was general recommendation but due to intensive cropping of rice, mining of K was noticed. Therefore, increased dose of potassium should be recommended to maintain the replenishment of K in soil system and other side benefit cost ratio should not affect negatively. The treatment received extra doses of T6 to T7 (60:30:50 mg kg-1) showed highest growth in plant and yield of rice but in steady state which is not beneficial economically. Hence, in T7 benefit cost ratio will be poor. In the present experiment, T6 maintains all fulfillment of K whether in plant or soil system.