EFFECT OF SUPPLEMENTAL POTASSIUM ON THE GROWTH AND YIELD OF RICE DIFFERING IN SALT TOLERANCE

Abstract

A pot culture experiment was conducted to study the reclamation of salinity by potassium supplementation on growth and yield of rice. The experiment was completed using two varieties namely Pokkali and BRRI dhan 29, four salinity levels (0, 4, 8 and 12 dS m") and 4 supplemental K levels (80. tOO. 120, 140 kg K50 ha"). Plant height , root dry weight, shoot dry weight, total dry matter, effective number of tiller hill", panicle length. number of filled grain panicle", 1000 grain weight and grain yield hill" of the rice varieties were studied. Significant varietal differences were found in plant height, shoot dry weight, total dry matter, effective number of tiller hill". panicle length, number of filled grain panicle' , 1000 grain weight and grain yield hill" except the root dry weight where Pokkali is better than BRRI Dhan 29. All of the growth and yield parameters decreased with increasing salinity. With increasing potassium level all of the growth and yield parameters increased up to 120 kg K20 ha", then slightly decreased at 140 kg K20 ha". The yield is significantly increased with the increasing level of potassium. In considering the interaction effect of variety and potassium treatments, the highest results were shown at 120 kg 1(20 ha" in Pokkali The effect of different K levels at different salinity levels, the values of both growth and yield parameters increased with increasing of potassium level at same salinity treatment except at 140 kg K20 ha" where slight declination was observed. Interaction of variety, salinity and potassium also significantly affected all the growth and yield parameters. In most circumstances, the maximum result was in Pokkali at control salinity treatment with 120 kg K20 ha".