Abstract
Field experiments were conducted to assess the relative effectiveness of muriate of potash (MOP) and sulphate of potash (SOP) in rice and wheat for two consecutive years (1994-95 and 1995-96) on a sandy-clay loam soil. Whole of P and K along with one-third N were applied at sowing, while rest of the nitrogen was added in two equal splits at 35 days after sowing and at panicle/ear initiation stage. Response of each treatment was determined by recording observations on growth and yield parameters and chemical composition of plant and soil. The plant growth parameters like plant height, number of tillers per hill of rice and m-2 of wheat, grain and straw yield and 1000-grain weight of both the crops were not affected significantly by potassium fertilization. Both the K sources failed to improve the above mentioned parameters over control and no ill effect of chloride on the rice and wheat plant was observed. Both the K sources were similar in their effects on N, P and K concentration in grain and straw of both the crops. However, Cl concentration in grain and straw of the two crops increased significantly with the application of MOP. Though chloride concentration in wheat plant increased initially with MOP application but decreased with advancement of plant growth. Subsoil chloride contents increased with the application of MOP. Key words: potassium sources, rice-wheat cropping system