PEG浸种处理提高烟草种子活力的效应

用PEG浸种处理烟草种子,研究了不同浓度和处理时间组合对烟草种子活力的影响。结果表明,PEG处理能显著提高种子发芽率和幼苗活力指数,增强种子萌发时的呼吸速率和淀粉酶活性.且以20％PEG-6000浸种48h的效果最好。不同活力水平的种子经20%PEG处理后,幼苗活力指数明显提高,处理组的超氧物歧化酶(SOD)、过氧化氢酶(CAT)和过氧化物酶(POD)活性升高,膜脂过氧化产物丙二醛(MDA)含量和超氧阴离子(O2-)产生速率及电解质渗漏率显著低于对照组。研究还发现,PEG处理能减少低温吸胀期间种子内电解质渗漏量及渗漏速率,并提高种子在低温下的萌发率,增强幼苗抗冷性。

The Effects on Increasing Seed Vigor of Tobacco by PEG

The tobacco seeds were soaked in PEG solution, the effects of PEG of different pretreatment group of concentration and treating time on seed vigor of tobacco were studied. The results showed that PEG could obviously promote the germination rate of tobacco seeds and vigor index of tobacco seedlings. It also could increase the rate of respiration and a-amylase activities of tobacco seeds during germination and the pretreatment with 20% PEG for 48 hours was the best effective. With the treatment of 20% PEG, the activity of superoxide dismutase (SOD), the peroxidase (POD) and catalase (CAT) increased compare to the control in different vigor levels seeds. While the content of MDA and the rate of O2- production and electric conductivity decreased significantly than those the control. This indicate also that electrolyte leakage lesser and slower speed than control during the imbibition of seeds, and increased germination rate of seeds and the chilling resistance of seedling under lower temperature through immersed pretreatment with PEG.