种子活力的生理和遗传机理研究进展

Advances on Seed Vigor Physiological and Genetic Mechanisms

种子活力是反映种子在各种条件下具有的潜在萌发与出苗能力,以及贮藏性能的性状,受遗传、种子发育期间的环境条件及贮藏条件等因素共同决定,较种子标准发芽率更能说明种子质量的优劣。近年来,国内外有关种子活力的生理机理研究表明,在种子发育后期,LEA蛋白、寡聚糖和ABA等抗逆物质与种子活力的形成有关,而膜脂过氧化作用、染色体及基因的畸变和胚蛋白的降解等则被认为是引起或加剧种子活力衰退即种子老化劣变的重要原因。种子活力是一个由多基因控制的数量性状,目前拟南芥和水稻等模式植物种子活力的遗传学与QTL分析主要集中在形态学指标,而生理学指标的分析较少。与种子活力有关的QTL位点的数量、在染色体上的位置、遗传效应及其与环境互作效应等,与植物种类和种子活力性状指标有关,遗传作用特点不尽相同。

Seed vigor is a more promising seed quality character reflecting potential seed germination, field emergence and seed storage ability under different conditions than standard germination. Standard germination is influenced by genetic background and environmental effects during seed development and storage conditions. Latest research on physiological mechanism in seed vigor showed that at the late stage of seed development, the development of seed vigor involves some stress-resistant substances including LEA protean, oligosaccharides and ABA. Whereas the loss of seed vigor, or seed aging and deterioration, could be attributed to lipid peroxidation, chromosome deform and genes aberrance, and embryo protein degradation etc. Seed vigor is a quantitative character controlled by multi-genes. Genetic and QTL analyses on seed vigor trait in model plants, such as Arabidopsis and rice, are mostly concentrated on related morphology traits, few physiological traits have been researched. It was concluded that all of the QTL genetic characteristics of seed vigor-including QTL quantities, its locus on chromosome, genetic effects, and interaction effects between genetic and environment-tiffered with plant species and used seed vigor traits.