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(一)影响高产的农业气候定量指标上海地区后季稻产量不稳,有多方面的因素,从近几年后季稻的产量结构看,有效穗数、实粒数和千粒重很不稳定,年与年之间的差异较大。如有效穗数最多的1974年与最少的1977年相差8.14万/亩;每穗实粒数相差9.07粒;千粒重相差2.21克。造成这种差异的原因,与后季稻不同生育期的气候条件有关。例如1974年减产主要是空秕率高,每穗实粒数少,原因是减数分裂期(9月
(I) Quantitative Indicators of Agricultural Climate Affecting High Yield The output of post-season paddy in Shanghai is unstable due to various factors. From the output structure of the late season rice in recent years, the effective spike number, the actual grain number and the 1000-grain weight are very unstable. The difference between years is bigger. If the effective spike in 1974 and the least in 1977 a difference of 81,400 / mu; spikelets per panicle difference of 9.07 grains; grain weight difference of 2.21 grams. The reasons for this difference are related to the climatic conditions at different growth stages of the latter season. For example, the decrease in production in 1974 was mainly due to the high vacancy rate and the small number of grains per panicle due to meiosis (September