盐胁迫对不同基因型冬小麦发芽和出苗的影响

研究了不同浓度NaCl胁迫对4种不同基因型冬小麦种子发芽及出苗的影响。试验结果表明,50～150mmol/LNaCl处理对小偃6号和NR9405发芽的抑制作用较小,50、100mmol/LNaCl处理对陕229和RB6的发芽有一定促进作用;150～200mmol/L的盐浓度可能是影响小麦种子萌发的临界浓度。盐胁迫下,小麦种子发芽率、发芽指数及活力指数下降,且活力指数对盐害反应最为敏感。盐胁迫抑制小麦发芽期间芽和根生长,且在低盐浓度(50mmol/L)下根受抑制敏感程度大于芽;盐浓度上升则相反。小麦根数在低盐浓度(50mmol/L)下增加,高盐浓度(>150mmol/L)下减少。盐胁迫下,小麦种子出苗延迟,出苗率下降。不同基因型小麦发芽过程对盐胁迫的反应不同。小麦种子耐盐性存在基因型差异,4个冬小麦品种中,小偃6号种子耐盐性相对较好,NR9405次之。陕229和RB6耐盐性相对较差。

Effects of salt stress on germination and emergence of different winter wheat genotypes

In this paper, the effects of different NaCl concentration stress on the germination and the emergence of 4 kinds of winter wheat genotypes were studied. The results showed that the germination of Xiaoyan6 and NR9405 was not inhibited by the stress of 0~150 mmol/L NaCl solution concentration, and the 50~100 mmol/L salt concentration even could improve the germination of Shaan229 and RB6; the threshold concentration of NaCl solution affecting the germination of wheat was 150~200 mmol/L. Under salt stress, the germination percentage, germination index and vigor index decreased greatly, in which the vigor index was most sensitive to salt stress. Salt stress inhibited the growth of roots and sprouts during the germinating stage of wheat; the inhibition effect to roots was greater than that to sprouts under low salt concentration (50 mmol/L), and it was reverse under high salt concentration (more than 150 mmol/L). The amount of roots increased under low salt concentration (50 mmol/L), and decreased under high salt concentration (>150 mmol/L). Under salt stress, the emergence date was delayed, and the emergence percentage of wheat was decreased. Different winter wheat genotypes showed different responses to salt stress. Among the 4 tested winter wheat varieties, Xiaoyan6 and NR9405 were relatively good in salt-tolerance, but Shaan229 and RB6 were relatively sensitive to salt.