干旱胁迫对大豆种子萌发的影响

Effect of Drought Stress on Germination of Soybean

为了考察干旱胁迫对大豆种子萌发的影响,以聚乙二醇(PEG-6000)作为渗透剂模拟干旱胁迫,研究了在6种不同浓度(0、5%、10%、15%、20%、25%)PEG渗透胁迫下大豆吉农18(JN18)及其根系突变体(M18)种子萌发的特征和幼苗生长的状况。结果表明:干旱胁迫对大豆种子萌发和幼苗生长均有较强的抑制作用,JN18和M18的发芽率、发芽势、发芽指数和活力指数均随着PEG处理浓度增加呈下降趋势,且在20%PEG处理下,M18的发芽率、发芽指数和活力指数显著高于JN18(P<0.05);JN18和M18长势均与PEG浓度呈负相关,且二者在15%PEG处理下的根系性状存在极显著差异(P<0.01),同时,二者胚芽长差异显著(P<0.05)。初步认定M18较JN18具有更强的耐旱性。

To evaluate the effects of drought stress on seed germination and seedling growth of soybean,drought stress simulated by different concentrations of polyethylene glycol（PEG-6000）,0,5%,10%,15%,20% and 25% of PEG-6000 were applied at soybean germination stage as drought stress conditions,and the germination rate,germination potential,germination index,vigor index,taproot length,number of lateral roots,total length of lateral roots and plumule length of JN18 and its root mutant M18 were analyzed,taking JN18,a wild-type line as control. The results showed that seed germination and seedling growth of soybean were significantly inhibited by drought stress in this experiment. With the strengthening of drought stress,seeds germination rate,germination index and vigor index were significantly reduced,taproot length,total length of lateral toots and plumule length of the seedlings were shortened,the number of lateral roots,root weight,lateral root weight and plumule weight were decreased. The results showed that M18 had higher seeds germination rate,germination index and vigor index under the same PEG treatment. M18 also showed a strong growth advantage under the same drought stress. Many indices of M18 were higher than JN18,including taproot length,number of lateral roots,plumule length etc.. It was suggested that the ability of drought resistance of M18 was more superior than JN18.