聚乙烯醇预处理提高大豆种子活力和抗冷能力的作用

聚乙烯醇预处理大豆种子和聚乙二醇一样,能明显地提高种子的活力、萌发率和抗冷能力。其主要作用可能是:在整个吸胀过程中减少了吸水速度,使膜的修复作用有足够的时间;启动和改善种子内部的生理代谢过程.保证了生长胚根有更多的物质供应。

Effects of Polyvinyl Alcohol Pretreatment on the Increase of Soybean Seed Vigour and its Protection Against Chilling Injury

The effects of PVA pretreatment of soybeanseeds prior to low temperature imbibition on theregulation of seed vigour, germination and coldresistance were studied. When soybean seeds were imbibed at chil-ling injury temperature, the vigour, germinationand cold resistance of the seeds were markedly re-duced, and a large amount of nutrients of leakedout during imbibition. As a result of the imbi-bition, the seed respiratory rate was greatly dec-reased. The decrease of transportation rate ofstored nutrients from cotyledon to growing plu-mular axis caused the reduction of growth vigourof seedlings and produced a lot of abnormal seed-lings. Pretreating soybean seeds with PVA andPEG could significantly reduce the damage duringimbibition at chilling injury temperature. Themain effects of PVA treatment are as follows:reducing the water absorption rate of the seeds,giivng enough time for reparation and recom-bination of membrane;starting and improving theinternal physiological metabolism of seeds and en-suring more supplies of nutrients available forthe growth of embryos.