嘉兴地区历史上就是一个晚粳高产区,单季晚稻在全区粮食生产中占重要地位,凡是单季晚稻产量高的年分,全区粮食总产量就高。解放后,由于党加强了对粮食生产的领导,调动了广大农民的生产积极性,单李晚稻的产量更加提高,到1953年全区平均亩产达到527斤。1955年几个原晚粳主产县分又获得进一步高产,其中平湖全县平均亩产就达557斤,吴兴546斤。但近年来却有逐步下降的趋势,到1961年,全区单季晚稻平均亩产只382斤,特别是素称单季晚粳高产地的嘉兴、嘉善、平湖、吴兴等县下降幅度较大。改制以来,扩种双季稻为全区粮食增产开辟了广阔的新途径,但单季晚粳一般仍占到水田总面积的40％以上,因此,研究单季晚稻减产原因,探求进一步提高其产量的新途径,是十分重要的。近年来单季晚稻低产的原因 Jiaxing is historically a high yielding area for late japonica rice. The single season late rice occupies an important position in grain production in the whole region. After the liberation, with the strengthening of the party’s leadership over food production and the mobilization of farmers’ enthusiasm for production, the output of monocotyledon rice rose even more. By 1953, the average yield per mu in the entire district had reached 527 kg. In 1955, a few of the original late-producing japonica-producing counties got further higher yields, of which Pingcun County averaged 557 kg per mu and 546 kg of Wuxing. However, in recent years there has been a gradual downward trend. By 1961, the average single-season late rice yield in the region was only 382 kg. In particular, Jiaxing, Jiashan, Pinghu and Wuxing, . Since the system reform, the expansion of double cropping rice opens up a vast new way for grain yield increase in the whole region. However, single season late japonica rice still accounts for more than 40% of the total paddy field area. Therefore, The new way of production is very important. The reason for the low yield of single season late rice in recent years