减钾对华南早晚兼用型水稻产量形成、品质及钾吸收利用的影响

Effects of Reduced Potassium Fertilizer on the Yield Formation,Rice Quality and K Uptake and Utilization of Early /Late Season Rice in South China

在大田条件下,研究了低氮磷水平下施钾处理(常规施钾(225.0 kg/hm2)、减钾28%(175.5 kg/hm2)和不施钾(0 kg/hm2))对水稻粤晶丝苗2号、桂香占、华优8305和天优998的产量形成、品质及钾吸收利用的影响。结果表明,与常规施钾相比,减钾28%提高华优8305的结实率及天优998的有效穗和结实率,进而增产;桂香占的有效穗、结实率和千粒质量提高,但每穗总粒数下降,因而稳产;粤晶丝苗2号有明显的减穗减粒效应。减钾28%有利改善华优8305的稻米品质;不利改善另外3个水稻品种稻米碾磨品质。适度减钾对水稻剑叶和籽粒生理代谢酶活性无显著负面影响,减钾28%有利提高钾素利用率。

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 vari-eties （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 de-crease 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 favor-able to improve K utilization. Reduction K application had different effects on the yield and quality of different vari-eties used in both early and late season.