广适性光温敏不育系Y58S幼穗分化期耐冷性表现及生理机制

为了阐明水稻光温敏不育系幼穗分化期耐冷的形态生理机制,以耐冷不育系Y58S和4个生产上常用光温敏不育系为试验材料,研究了低温胁迫(17.5℃,10 d)下结实率、穗部形态、株高、光合特性以及抗氧化物酶系统等的变化。结果表明,低温胁迫下Y58S的幼穗分化期耐冷性在5个不育系中最强,与敏感的C815S和株1S相比,Y58S表现为株高和穗长降低幅度较小,保持较高结实率;光合作用受低温影响不显著,SPAD值、光合速率等光合指标无显著变化;SOD、POD活性降低幅度较小,MDA含量、相对电导率增幅较小。

Studies on Cold Tolerance of Widely Adaptable PTGMS Line Y58S and its Physiological Mechanism at the Booting Stage

In order to clarify morphological and physiological mechanisms of cold tolerance at the booting stage for rice photo thermo sensitive genic male sterile(PTGMS) lines,by using the cold tolerant PTGMS line Y58S and four other key PTGMS lines widely used in the production,the effects of low temperature stress(17.5 ℃ 、10 d)on seed setting rate,panicle traits,plant height,photosynthetic characteristics and antioxidant enzymes were studied in this experiment.The results showed that Y58S had the highest cold tolerance among the five PTGMS lines under the long-term cold stress.Comparing to the cold sensitive PTGMS lines C815S and Zhu1S,morphological and physiological mechanisms of cold tolerant line Y58S were as follows:higher seed setting rate and lower cold injury index;panicle length and plant height were reduced to a lesser extent;photosynthesis was effected not significantly by cold stress,the SPAD value and Pn value didn't change significantly;SOD and POD activity were slighter decreased,MDA content and relative conductivity were less increased.