浙江省水稻产量构成差异调查与合理种植密度分析

Grain yield difference investigation and reasonable planting density analysis of rice production in Zhejing Province

对浙江省23个水稻主栽品种、236块稻田产量的实际调查情况表明,水稻的产量差异普遍存在于品种和田块间,从变异系数看,每穗粒数和有效穗数的变异系数均显著大于千粒重,是导致品种间和田块间产量差异的主要因素。相关分析表明,不同类型水稻的产量均与每穗粒数的相关性最大,其中双季晚籼稻和单季常规粳稻分别达极显著和显著正相关,大穗品种的产量相对较高。水稻的产量随种植密度的增加先增加后下降,对单季籼稻,种植密度在（1.00~1.20）万丛/667m2时,出现产量〉650 kg/667m2的概率较大,而种植密度在（1.20~1.40）万丛/667m2时,出现产量〈500 kg/667m2和〉650 kg/667m2的概率均较小,稳产的把握较高;对双季晚稻,种植密度以（1.10~1.40）万丛/667m2为宜。

Rice yield difference widely exists among different cultivars and paddy fields.At present,rice yield potential is hard to breakthrough,so decreasing yield difference and increasing yield of different paddy field is one of the effective ways to increase rice average yield.In this study,in order to analyze the cause of rice yield difference,we investigated the grain yield and 23 typical cultivars,which were planted in 236 different paddy fields in Zhejiang Province,including early-season indica conventional rice,single-season indica hybrid rice,single-season japonica hybrid rice,single-season japonica conventional rice and late double season indica hybrid rice,and further analyzed influence of planting density on grain yield.The results showed that the coefficient of variation of grains per panicle and effective panicles per plant were larger than that of 1 000 grain weight,indicating they were the main causes of yield difference.Relation analysis indicated that the correlation coefficient of grains per panicle and yield was the largest in yield components and was significant in single-season japonica conventional rice and late-season indica hybrid rice,and rice cultivar with large panicle usually had higher yield than cultivar of little panicles.With the increase of planting density,rice grain yield first increased then decreased.In single-season indica hybrid rice,when rice planted in（1.00-1.20）×104 per 667m2,the frequency of yield larger than 650 kg·667m-2 was higher,when planted in（1.20-1.40）×104 per 667m2,the frequency of yield between 500-650 kg·667m-2 was higher,and fewer paddy field was lower than 500 kg·667m-2,grain yield was relatively stable.In late-season indica hybrid rice,the reasonable planting density was（1.10-1.40）×104 per 667m2.