Abstract: Effects of K fertilizer(Conventional N(225. 0 kg /ha),reduction of K by 28%(175. 5 kg /ha) and without K(0 kg / ha)) on rice yield formation,rice quality and K uptake and utilization were studied using four varieties(Yuejingsimiao 2,Guixiangzhan,Huayou 8305 and Tianyou 998) in field experiment. Results showed that, compared with conventional K,reduction of K by 28% improved seed setting rate in Huayou 8305,increased both effective panicle numbers and seed setting rate in Tianyou 998,which result in increase in yield; Guixiangzhan showed stable in yield due to increase in effective panicle numbers,seed setting rate and 1000-grain weight,but decrease in grains number per panicle. For Yuejingsimiao 2,significant decrease in effective panicle numbers and grains number per panicle was found. Reduction of K by 28% improved rice quality in Huayou 8305,but showed unfavorable effect on milling quality in other experimental varieties. Moderate reduction of K showed no significant negative effects on physiological metabolism enzyme activity in flag leaf and grain,reduction of K by 28% was favorable to improve K utilization. Reduction K application had different effects on the yield and quality of different varieties used in both early and late season

Key words: Early/late season rice (Oryza Satava L.), Potassium reduction, Yield formation, Quality, K uptake and utilization

CLC Number: 

• S511