水稻突变体pe-1对弱光胁迫的响应机制

Response Mechanism of Rice Mutant pe-1 to Low Light Stress

以γ射线诱变籼稻双科早(Oryza sativa subsp.indica cv.‘Shuangkezao’)获得的早熟鲜绿突变体pe-1为实验材料,在三叶期和分蘖期进行弱光胁迫,探讨pe-1与野生型在形态特征、非生物胁迫相关酶活性及其调控基因表达量、叶绿素含量、叶绿体合成与降解及光形态建成相关基因表达对弱光响应的差异。结果表明,与野生型相比,弱光胁迫后,pe-1叶片黄化程度显著降低,株高和叶面积显著增加;三叶期和分蘖期的叶片中不同叶绿素含量变化不同。此外,pe-1叶绿素含量增加,且其抗氧化应激反应相关酶过氧化氢酶(CAT)和过氧化物酶(POD)的活性及相关基因的表达量均高于野生型,表明在弱光胁迫下pe-1活性氧清除能力增强,适应能力更强。pe-1的光形态建成相关基因表达量高于野生型,表明弱光处理下pe-1的光接收能力更强。综上,pe-1突变体具有抵御弱光胁迫的潜力,该结果有助于耐弱光水稻品种的选育。

This study utilized theγ-ray-induced early-maturation,fresh-green mutant line pe-1 from indica rice as an experimental material.At the trilobal stage and the tillering stage,we observed differences in morphological characteris-tics between pe-1 and wild type.In addition,we measured the activity of antioxidant-related enzymes and their regulatory genes expression,chlorophyll content and chloroplast synthesis and degradation-related gene expression,and photo-morphogenesis-related gene expression to detect the differences in the low light response between the pe-1 and wild type.The results showed that pe-1 exhibited less leaf yellowing,taller stature,and larger leaf area compared to wild type post-stress.The changes in chlorophyll content differed between leaves at the trilobal stage and the tillering stage.Addi-tionally,pe-1 resulted in increased chlorophyll content and elevated levels of the stress-responsive enzymes catalase and peroxidase,as well as increased expression of related genes.This indicates enhanced reactive oxygen species sca-venging and stronger adaptability to adverse conditions under low light conditions.Moreover,pe-1 exhibited increased expression levels of genes associated with photomorphogenesis,indicating superior light perception ability under low light intensities.In summary,the pe-1 mutant shows immense potential for survival under low light stress,contributing to the breeding rice with low light tolerance.