江苏太湖地区不同生育类型粳稻品种产量对不同播期气候因子的响应

光、温、水等气候因子是影响水稻产量形成的重要因素。为明确江苏太湖地区不同生育类型水稻产量对不同播期下气候因子变化的响应,以期为该地区不同生育类型品种合理安排播期提供依据,2018—2019年在苏州市农业科学院试验农场内以优质早熟品系苏1785和晚熟品种苏香粳100为材料,采用分期播种方法研究了2种不同生育类型水稻产量及其构成对不同播期气候因子的响应特性。结果表明,不同生育期类型品种随着播期推迟产量降低,晚熟品种产量在播期间和年度间产量变异较早熟品种大,稳产性较差。2个不同生育期类型品种有效穗、每穗总粒数随播期推迟均呈降低趋势,而结实率和千粒重播期间的差异因生育类型不同而异,早播使早熟品种结实率显著下降,迟播则使晚熟品种千粒重显著下降。迟播对早熟品种抽穗前光合势的影响程度高于晚熟品种,对抽穗后干物质积累量和群体生产率的影响则相反,迟播条件下晚熟品种茎鞘物质输出率和运转率下降迅速,不利于茎鞘物质的转运和灌浆物质的积累。相关分析表明,日照时数是影响水稻产量的首要气候因子,日均气温和有效积温对产量的影响因品种生育类型不同存在差异,日均气温和有效积温与早熟品种的产量呈显著正相关关系,而日均气温与晚熟品种的产量相关不显著,气候因子对产量的影响表现为:日照时数>日均气温,有效积温>降雨量。

Response of yield of different growth types of japonica rice varieties to climatic factors at different sowing dates in Taihu region of Jiangsu province

Light,temperature,water are important factors affecting the formation of rice yield.In order to investigate the response of different growth types of rice to climate factors under different sowing dates in Taihu region of Jiangsu province and to provide the basis for reasonable sowing date arrangement of different growth type varieties in the region,two different growth types with high-quality early maturing line Su 1785 and late maturing variety Suxiangjing 100 were planted at different sowing dates from 2018 to 2019 in the experimental farm of Suzhou Academy of Agricultural Sciences.The results showed that the yield of varieties with different growth stages decreased with the delay of sowing date.The yield variation of late maturing varieties was larger than that of early maturing varieties during sowing dates and years,and the stability of yield was poor.The effective panicles and the total grains per panicle of two varieties at different growth stages decreased with the delay of sowing date,while the differences of sowing dates of seed-setting rate and 1000-grain weight varied with different growth types.Early sowing dates significantly reduced the seed setting rate of early maturing varieties,while late sowing dates significantly decreased 1000-grain weight of late maturing varieties.The effects of sowing dates on photosynthetic production before heading stage of early maturing varieties were significantly higher than that of late maturing varieties,while the effects on dry matter accumulation and population productivity after heading stage were opposite.Under the condition of late sowing dates,the stem sheath matter export rate and translocation rate of late maturing varieties decreased rapidly,which was not conducive to the transport of stem sheath materials and accumulation of filling materials.The correlation analysis showed that sunshine hours were the first most important climatic factors affecting rice yield.The effects of daily average temperature and effective accumulated temperature on rice yield varied with different growth types.Daily average temperature and effective accumulated temperature were significantly positively correlated with the yield of early maturing varieties,but not with late maturing varieties.The effects of climate factors on yield were as follows:sunshine hours>average daily temperature,and effective cumulative temperature>precipitation.