NaCl胁迫对甜瓜种子萌发的影响

Effects of Salt Stress on Germination of Muskmelon Seeds

采用培养皿发芽法研究了不同浓度NaCl胁迫对甜瓜种子萌发的影响。结果表明:种子在吸胀阶段受盐胁迫影响较小,当种子萌动后高盐浓度对种子吸水有抑制作用。50mmol·L-1NaCl处理,对黄河蜜胚根生长有促进作用;50mmol·L-1以上,随着盐浓度增加,黄河蜜、白沙蜜、甘黄金种子的发芽速度逐渐降低,相对发芽指数、相对活力指数、胚根生长量均下降。盐胁迫对种子α-淀粉酶活力和膜修复的抑制可能是造成甜瓜种子萌发推迟和发芽势下降的主要原因。

The effects of NaCl stress at different concentrations on germinating characters of muskmelon seeds were studied in culture dishes. The results showed that higher concentration of NaCl stress slowed water absorption of the germinating seeds, though no effect was observed at early stage of water absorption. Lower concentration of 50 mmol· L^-1 promoted the growth of Huanghemi＇s radicle,with the increasing of NaCl concentrations, germination process was delayed, relative germination index,relative vitality index and relative α-amylase activity were all decreased. The results imply that inhibition of α-amylase activity and membrane restoration may be important reasons of postponed germination and declined germination vigor under salt stress.