光温条件对水稻结实及干物质生产的影响

试验研究了水稻抽穗结实期开花、乳熟和蜡熟三阶段弱光照和高温对结实和干物质生产及分配的影响。结果表明 ,①各阶段的光照强度下降到自然光强的 70 %时 ,不会显著影响单穗籽粒产量 ;但光强下降至5 0 %时 ,则会使空、秕粒增加 ,导致结实率下降而使单穗籽粒产量显著降低。弱光照对千粒重的影响不显著。②各阶段在 36℃以上高温时 ,单穗籽粒产量和结实率均显著下降 ,除开花阶段外 ,还有明显降低千粒重的趋势。③光照不足和高温都使单茎干物质积累速率和积累量降低 ,但光照不足时使干物质在穗中分配比率提高 ,而高温则相反。另外 ,抽穗开花阶段光照不足使茎鞘养分运转率下降 ,乳熟和蜡熟阶段光照不足则使运转率提高。高温除蜡熟阶段使运转率提高外 ,在抽穗开花和乳熟阶段则均使运转率大大降低。

The Influence of Temperature and Light on Grain-filling, Dry Matter Production of Rice

The influence of temperature and light on fertilization, grain-filling, dry matter production and partitioning of rice in different stages from heading to maturity under pot test condition was studies in 2000,2001 and 2002 The result indicated that,①the grain yield of single tiller was not significantly decreased when the light intensity was lowered to 70% of natural light intensity, but it was significantly decreased due to the empty and unfilled grain that led to the decrease of the ripened grain rate when the light intensity was lowered to 50% of natural light intensity The low right intensity did not significantly affect the 1000 grain weight ②The grain viele of single tiller and ripened grain rate were both decrease under temperature higher than 36℃, and 1000 grain weight was obviously lowered except in the flowering stage ③The rate and quantity of dry matter assimilation were decreased under low light intensity and high temperature on But the rate of dry matter partitioning of the ear was increased under low light intensity, and decreased high under temperature condition Inaddition , the transfer rate or nutrients in the stem and sheath was lowered under low light intensity condition in the heading and flowering stage,but was increased in the other two stage High temperature in dough stage increased the rate of transfer, decreased the rate of transfer, in the other two stage