不同生育阶段遮阴对水稻籽粒充实和产量的影响

Effects of Different-growing-stage Shading on Rice Grain-filling and Yield

以Ⅱ优498、川香9838等16个杂交稻组合为材料,采用裂区设计研究了不同生育阶段(分蘖期、拔节孕穗期、灌浆期)弱光对水稻籽粒充实和产量的影响。结果表明:不同生育阶段遮阴对水稻籽粒充实和产量有不同程度的影响,分蘖期遮阴主要使水稻有效穗大幅度降低,并使籽粒充实度和充实率分别减少3.00%和4.03%,减产17.34%;拔节孕穗期遮阴主要减弱水稻中期的营养生长和穗分化程度,使充实度和充实率增加3.84%、9.94%,但产量降低41.35%;灌浆期遮阴严重影响了水稻的授粉、结实及籽粒充实,使其充实度和充实率分别降低了7.41%和16.64%,产量降低53.93%。聚类分析结果表明,一丰8号和冈优906等组合较耐弱光。

A split-plot design was used as the main plot treatment to study the effects of differentgrowing-stage shading （tillering stage, elongating-heading stage and filling stage） on rice grain filling and yield, with 16 hybrid rice combinations as the subplot treatments. The results showed that the grain filling and yield were obviously affected by shading. During tillering stage, shading made the effective panicles reduce significantly, the filled grain degree and filled grain percentage decline by 3.00%, 4. 03% respectively, and the yield by 17.34%. During elongating stage, shading made the filled grain degree and filled grain percentage higher than those of the control by 3.84% and 9.94%, but the yield declined by 41.35%. During filling stage, shading affected pollination and grain growth seriously, and made filled grain degree and filled grain percentage decline by 7.41% and 16.64% respectively, while the yield declined by 53.93%. At last, the cluster analysis showed that hybrid rice combinations Yifeng-8 and Gangyou 906 had better tolerance of shading.