High temperatures during the grain-filling period do not reduce the potential grain dry matter increase of rice
High temperatures during the grain-filling period do not reduce the potential grain dry matter increase of rice
复制标题
DOI：
10.2134/agronj2004.0406
复制
发表时间：
2004-03-01
期刊：
影响因子：
2.1
通讯作者：
Uemuki, N
中科院分区：
文献类型：
--
作者：
Kobata, T;Uemuki, N
水稻（Oryza sativa L.）增加谷粒干物质增加速率（GIR），但GIR的这种增加不足以完全补偿伴随的GFP减少，结果，谷粒产量降低。人们认为，随着温度的升高，GIR的不足意味着作为汇容量的潜在GIR的减少。然而，我们怀疑，缺乏同化物供应的粮食，而不是潜在的GIR下降，降低GIR，并导致减少粒重。我们的目的是确定在较高温度条件下，如果GFP期间的同化物供应足以维持增加的GIR，则粒重是否可以达到全部潜力。在日本西部的三个地方种植水稻超过3年。在一个位置，在GFP期间用塑料膜覆盖地块以增加温度。在GFP期间，当平均温度在23和29 ℃之间时，成熟时的小穗填充百分比（F%）在70和90%之间变化。当在GFP期间将地块稀疏至一半密度时，所有F%通过基于累积温度的单一逻辑方程近似，上限为90%。因此，细化可以克服较低的F%。这些结果表明，潜在的GIR水稻并没有减少高温期间的GFP。通常与这种条件有关的产量降低可能是由于不能向谷物提供同化物以满足加速GIR的要求。
High temperatures during the grain-filling period (GFP) of rice (Oryza sativa L.) increase the grain dry matter increase rate (GIR), but this increase in GIR is insufficient to completely compensate for the concomitant reduced GFP, and as a result, grain yield decreases. The shortfall in GIR as temperatures increase has been believed to signify a reduction of the potential GIR as a sink capacity. However, we suspect that lack of assimilate supply to the grain, rather than the decreased potential GIR, lowers the GIR and causes reduced grain weight. Our objective was to determine if the grain weight could reach full potential under higher temperature conditions if assimilate supply during the GFP was sufficient to sustain the increased GIR. Rice was grown at three locations in western Japan over 3 yr. At one location, plots were covered with plastic film during the GFP to increase temperature. Spikelet filling percentages (F%) at maturity varied between 70 and 90% when mean temperatures ranged between 23 and 29degreesC during the GFP. When plots were thinned to half density during GFP, all F% were approximated by a single logistic equation based on accumulated temperature, with a ceiling of 90%. Hence, thinning can overcome the lower F%. These results suggest that potential GIR in rice is not reduced by high temperatures during the GFP. Yield reductions commonly associated with such conditions are likely due to the failure of assimilate supply to the grain to meet the requirements of the accelerated GIR.