不同时期水分胁迫对水稻生长特性和产量形成的影响

通过网室盆栽试验,研究了不同时期水分胁迫对杂交稻生长和产量的影响。结果表明,中优6号各生育期不同程度水分胁迫都会影响水稻产量,减产最大的时期是穗分化期和开花期,产量比对照下降49.4%和30.7%。水稻分蘖期受水分胁迫对穗数影响最大。穗分化期水分胁迫对总粒数和结实率影响最大,开花期水分胁迫对千粒重影响最大,结实率与穗抽出率存在正相关,相关系数达到0.9211。穗分化期和开花期重度水分胁迫,穗抽出率明显下降。在水分胁迫条件下,光合速率下降主要发生在下午。讨论了水分胁迫对水稻产量和生长的影响。

Effects of water stress on rice growth and yield at different growth stages

A pot experiment was carried in isolation chamber to study the effects of water stresses on rice growth and yield at different growth stages. The results showed that water stresses ouccuring during any periods of rice growth affected Zhongyou 6 in yield and growth and the biggest yield decrease appeared in the heading and flowering periods during which they reduced the yield of Zhongyou 6 by 49.4% and (30.7%,) respectively. The water stresses occurring in the tillering stage affect the panicle number most and the water stresses in the panicle-differentiating period affected the total seed number and the fruiting rate most, and the water stress occurring in the flowering period affected the kernel weight most; the fruiting rate had positive correlation with the heading rates with a correlative coefficient of 0.9211. Severe water stresses occurring in the panicle-differentiating and flowering periods could result in remarkable decline of the heading rate. Under water stresses, the decrease in photosynthetic rate mainly took place in the afternoon. In addition, the effects of water stresses on rice growth and yield were discussed.