不同肥密条件处理对水稻产量与品质影响

采用二次回归正交旋转组合设计,在大田条件下建立了不同播种量、插秧密度和氮、磷、钾施用量处理的水稻群体,调查并模拟其产量和品质性状。试验结果表明:产量与氮肥施用量呈二次曲线趋势,氮肥施用量过多,会导致参试水稻品种贪青晚熟,籽粒不饱满,成粒率和千粒重下降,垩白增加,并使沈稻7号加工品质下降,但沈稻3号高产群体的需氮量超过沈稻7号。沈稻3号插秧穴距10～15cm时适量施用钾肥,沈稻7号插秧穴距15～20m时,适当施用氮、磷、钾肥,可以显著提高产量。扩大穴距,会减少单位面积穗数,但可显著增加每穗粒数。但插秧穴距超过20cm或每盘播种量超过80g会降低加工品质。单位面积穗数与每穗粒数间存在显著的负相关,糙米率、精米率、整精米率间存在显著的正相关,垩白度与垩白粒率间存在显著的正相关。

Effect of Different Amounts of N, P, K and Plant Density on Grain Yield and Quality of Rice

In order to increase grain yield and quality of rice,the experiments with the design for canonical analysis in investigating and simulating the effect of nitrogen,phosphorus and potassium application levels,seeding rate and transplanting density on the growth and development of rice plants were performed.The results indicated that grain yield and the N amount could be simulated in quadratic equation.Heavy dressing nitrogen caused the plants of two varieties late maturity,insufficient grain filling,low ripened grains and 1000-grain weight,and more chalky grains,besides low milling quality of Shendao 7.The suitable amount of N application for high-yielding plant population of Shendao 3 was higher than that of Shendao 7.The grain yield increased when the hill spacing was 10~15 cm for Shendao 3 companied with applying sufficient K and 15~20 cm for Shendao 7 companied with suitable amounts of N,P and K.Expanding hill spacing could reduce panicles per unit area but increase the spikelets per panicle.If the hill spacing was more than 20 cm,or the sowing rate was more than 80 g per plate,the milling quality would decrease.There were negative correlations between the panicles per unit area and spikelets per panicle,positive correlations between the brown rice rate and milled rice rate,brown rice rate and head rice rate,milled rice rate and head rice rate,and chalky grain and chalkiness.