不同氮钾用量配比对直播稻产量和品质的影响

Effects of Different Proportions of Nitrogen and Potassium amounts on Grain Yield and Quality of Direct-seeded Rice

为提供水稻直播栽培合理的氮钾配施技术,研究了120,165,210 kg/hm23个施氮水平以及90,150,210 kg/hm23个施钾水平的不同配比对直播稻产量和品质的影响。结果表明,产量以N2K3配比最高。不同氮钾配比对直播稻产量影响显著。氮肥用量以165 kg/hm2适宜。相同氮肥用量下,产量随着施钾量的增加而增加,增施钾肥提高有效穗和每穗粒数。要获得高于9 000 kg/hm2产量,施氮量需160～180 kg/hm2、氧化钾需180 kg/hm2以上。在低氮水平下,增施钾肥有提高籽粒最大灌浆速率的趋势,中、高氮水平下,增施钾肥籽粒最大灌浆速率呈下降趋势。N2水平的活跃灌浆期最短、籽粒最大灌浆速率最大。粒质量与籽粒最大灌浆速率和活跃灌浆期呈正相关。增施钾肥降低垩白米率和垩白度。胶稠度有随着氮钾施用量增加而下降、碱消值随氮钾施用的增加而提高的趋势。胶稠度和碱消值与籽粒灌浆特征和稻谷产量水平关系密切。

In order to provide rational application technology of dosage of nitrogen and potassium in direct-seeded rice,the effects of different proportions of three nitrogen amount levels of 120 kg/hm2,165 kg/hm2,210 kg/hm2 and three potassium amount levels of 90 kg/hm2,150 kg/hm2,210 kg/hm2 on the grain yield and quality of direct-seeded rice were studied.The result showed that the proportion of N2K3 had the best yield.The effects of different proportions of nitrogen and potassium amounts were remarkable on yield of direct-seeded rice.The nitrogen dosage of 165 kg/hm2 was optimal.The yield increased along with the application amount of potassium under the same nitrogen amount level.The effective panicles and grain nmbers of per panicle increased along with the application amount of potassium.To achieve the yield of over 9 000 kg/hm2,the nitrogen amount of 160-180 kg/hm2 and potassium oxide amount of over 180 kg/hm2 were required.There was a trend that the maximum grain filling rate was increased by added potassium amount under the lower nitrogen level,and that the maximum grain filling rate represented a downtrend when the potassium amount increased under higher nitrogen level.The active grain filling period was the shortest and the mean grain filling rate was the biggest at the levels of 165 kg/hm 2 nitrogen.The grain weight was positively correlated with maximum grain filling rate and active grain filling period.Added amount of potassium fertilizer reduced the chalky grain rate and chalkiness.The gelconsistency decreased along with the application amount of potassium.The alkali spreading value increased along with the application amount of potassium and nitrogen.The gelconsistency,alkali spreading value and the character parameters of grain filling,grain yield level were closely correlated.