Potassium in soil exists in several forms like solution, exchangeable, non-exchangeable and lattice K. These potassium forms are in equilibrium with each other. However, plant takes up K mostly from exchangeable and solution form. The present study was conducted on farmers’ field at Khamkheda (Dist. Bhopal) under the project initiated by Indian Institute of Soil Science (ICAR), Bhopal. The experiment was laid out in a Randomized Block Design (RBD). The entire experimental area at the farmers’ field was divided into five sampling blocks representing the replications to reduce soil heterogeneity. Each block was divided into 4 unit plots with raised bunds as per treatments. Thus, the total number of the unit plots was 20 (5×4). The size of each unit plot was (59.4 m x 36 m) and the spacing between blocks was 100 cm and the plant to plant spacing was maintained at 22 cm. The average maximum, and minimum temperature and relative humidity were 32.25, 23.26 and 81.80% respectively during crop growing period of rice. The treatments detail was T1 [0 kg K2O/ha (K0], T2 [48 kg K2O/ha (K40)], T3 [96 kg K2O/ha (K80)] and T4 = Farmers’ Practice (KFP)*consists of N, P2O5 and K2O @ 104, 73 (P=32) and 0 kg/ha, respectively and Zn @ 2.1 kg/ha. In the field experiment the recommended doses of nutrients were N @ 120 kg/ha, P2O5 @ 60 kg/ha (P=26) and Zn @ 2.5 kg/ha. The treatment T3 (96 kg K2O/ha i.e. K80) resulted in maximum plant height (92.8 cm), number of tillers per meter (198.6), number of leaves per plant (59.4), number of panicles (195.6), length of panicle (30.2 cm), weight of panicle (5.04 g), number of grains/panicle (251.2), filled grains/panicle (233.2), unfilled grains /panicle (18.0), test weight (22.05 g), grain yield (5784 kg/ha), stover yield (6374 kg/ha), harvest index (47.72), available nitrogen, phosphorous and potash in soil (222.54, 31.58, 330.6 kg/ha). The nutrient content in grain and stover was also increased as 1.2, 0.21, 0.15 per cent NPK content in rice grain and 0.28, 0.05, 2.23 percent NPK in rice stover. The water soluble potash (7.80), exchangeable potash (139.8), available potash (147.6) and non exchangeable potash 540.83.The treatment T3 (96 kg K2O/ha i.e. K80) has resulted in reduced cost of cultivation of Rs 39684, gross monetary return Rs 104146, net monetary return Rs 64462 and benefit cost ratio of 2.62 as compared to all other treatments.

Download this article as