PEG模拟干旱对胡麻种子萌发及幼苗生长的影响

Effects of simulated drought stress by PEG on sprouting and seedling growth of flax(Linum usitatissimum L.)

采用PEG模拟干旱胁迫处理,研究胡麻种子萌发及幼苗生长情况。结果表明,PEG对成苗的影响大于萌发,低浓度PEG(5%)对萌发有促进作用,15%PEG为适宜的胁迫浓度。在15%PEG胁迫下,胡麻种子活力不同程度降低,主要表现在发芽指数(GI)、活力指数(VI)、下胚轴生长受到显著抑制,幼苗鲜重降低,但对初生根生长的影响不一致;幼苗相对电导率(REC)、丙二醛(MDA)、脯氨酸(Pro)和可溶性糖(SS)含量均显著增加,增幅在初生根、下胚轴、子叶中存在差异。

The polyethylene glycol （PEG） was used to simulate drought to study the germination and seedling growth of flax. The results showed that seedling was more sensitive to PEG treatment than germination. 5% PEG promoted sprouting, and 15 % PEG were appropriate for simulating drought. Under 15 % （w/v）PEG treatment, seed vigor was reduced, mean germination index （GI）, vigor index（VI）, hypocotyl elongation and fresh weight of seedling were repressed significantly, but no consistency was found on the primary root growth; Significant increase was also found in REC, content of malonaldehyde （MDA）, proline （Pro） and soluble sugar （SS） of seedling, and difference was found among primary root, hypocotyl and cotyledon.