外源ABA和GA_3对NaCl胁迫下黄瓜种子萌发特性的影响

NaCl胁迫下,黄瓜种子的发芽势、发芽率、发芽指数和活力指数以及胚根长和鲜重均显著下降,且随NaCl浓度的增加下降的幅度增大.外源ABA和GA3浸种处理均能显著缓解不同浓度NaCl对黄瓜种子萌发的抑制作用,1×10-6mol/L ABA和25 mg/L GA3处理可使75 mmol/L NaCl胁迫下黄瓜种子发芽指数比对照分别提高81.67%和77.78%;同时外源ABA和GA3浸种处理还可不同程度地缓解NaCl胁迫对黄瓜种子α-淀粉酶活性的抑制作用,提高黄瓜幼苗子叶中超氧化物歧化酶活性.

Effects of exogenous ABA and GA3 on germination characteristics of cucumber seeds under NaCl stress

Germination vigor,germination rate,germination index,vigor index,radicle length and radicle fresh weight of cucumber seeds decreased significantly under NaCl stress with the decreasing of salt concentration.Soaking seeds in exogenous ABA and GA_(3) could ease the inhibition of NaCl on seed germination.1×10~(-6)mol/L ABA and 25 mg/L GA_(3) treatments could relieve the inhibition of 75 mmol/L NaCl stress on the seed germination,and the seed germination indexes were increased by 81.67 % and 77.78 % respectively compared with the contrast.Under salt stress,α-amylase and superoxide dimutase activity of cucumber seeds treated with exogenous ABA and GA_(3) were higher than those of the seeds treated only with NaCl.