人工老化和修复处理对小麦种子活力及生理特性的影响

Effects of Artificial Accelerated Aging and Repairing Process on Seed Vigor and Physiological Characteristics of Wheat Seeds

种子在贮藏过程中,会出现老化现象,使种子活力下降,生理特性发生改变。本实验采用高温高湿(T=52.3℃,RH=80%)人工老化方法处理小麦种子,并以500mg/L抗坏血酸(AsA)、20%聚乙二醇(PEG)6000、500mg/L赤霉素(GA_3)3种溶液进行老化种子的修复,人工老化及修复后的种子经室内发芽试验,分别测定种子发芽指标、种子活力、过氧化物酶(POD)活性、丙二醛(MDA)含量变化情况。结果表明,经人工老化处理后,小麦种子的发芽势下降2.27%,发芽率下降2.67%,种子活力(TTC还原强度)下降7.29%,这三者虽都有所下降,但未达到显著水平(p<0.05);而老化种子的活力指数和发芽指数下降显著,分别较未老化处理种子下降35.86%和51.51%。PEG修复处理能显著提高老化种子的发芽指数;GA3修复处理对老化种子活力指数的修复效果最好;AsA和GA_3修复处理使老化种子的MDA含量显著降低,但未达到未经处理种子的MDA含量水平;PEG、GA_3和AsA修复处理对POD酶活性都有一定程度的提高,但影响不显著。

With the extension of storage time,the seeds aging occur,the activity decreases,and physiological characteristics change.In this study,high temperature and high humidity（T=52.3℃,RH=80%）artificial aging method was used to deal with the wheat seed,and 500 mg/L ascorbic acid（AsA）,20% polyethylene glycol（PEG）6000,500mg/L gibberellinic hormone（GA_3）three solutions were used to repair aging seeds.Seeds artificial aging and repaired by the indoor germination test,seed germination index,seed vigor,peroxidase（POD）activity,malondialdehyde（MDA）content were measured.The results showed that wheat seed germination potential declined 2.27%,germination rate decreased by 2.67%,seed vigor（TTC reducing intensity）fell 7.29% by artificial aging,all three had declined,but did not reach a significant level（p〈0.05）;and compared with the unaged seeds,the aging of seed vigor index and germination index decreased 35.86% and 51.51%.PEG repair treatment could significantly improve the germination index;The repair effect of GA_3 repair on aging seed vigor index was the best.;AsA and GA_3 repair treatment significantly reduced the content of MDA in aged seeds,but did not reach the MDA content of untreated seeds.PEG,GA_3 and AsA repairing had improvement for POD enzyme activity to some extent,but the effect was not significant.