NaCl胁迫对中国南瓜自交系及其杂交种幼苗生长的影响

Effects of NaCl stress on seedling growth of pumpk inbred lines and their hybrid lines

在组培条件下以田间表现生长势强的3份中国南瓜(Cucurbita moschataDuch.)自交系及其6份杂交种为试验材料,采用不同浓度的NaCl胁迫中国南瓜幼苗,10 d后调查幼苗的下胚轴伸长长度、鲜重和侧根发生数量,研究中国南瓜自交系和杂交种幼苗的生长抑制率、盐胁迫指数和半致死盐浓度。结果表明,中国南瓜杂交种的耐盐性比其自交系的耐盐性强,自交系幼苗在120 mmol/L NaCl浓度处理下生长受到严重抑制,而杂交种幼苗在160 mmol/L NaCl浓度处理下生长才受到严重抑制。6份杂交种幼苗间存在明显的耐盐性差异,360-3×112-2杂交种在不同NaCl浓度处理下下胚轴伸长长度抑制率、鲜重抑制率和盐胁迫指数较小,半致死盐浓度为134.72 mmol/L,耐盐性最强。

This study compared the salt tolerance of 3 pumpkin （ Cucurbita moschata Duch. ） inbred lines which showing stronger growth in the field condition and their 6 hybrids at the seedling stage. The seedling growth characteristics studied included hypocotyl length, fresh weight, later root numbers. The inhibition rates of growth, salt stress index,and lethal salt concentration of all the materials were also determined 10 d after NaCl stress. The results showed that： （ 1 ） salt tolerance of 6 hybrids were stronger than that of inbred lines; （2） NaC1 concentration of seriously inhibiting growth of 3 inbred lines and 6 hybrids seedlings were 120 and 160 mmol/L,respectively; （3） salt tolerance of 6 hybrids seedlings has significant differences under the condition of 40 - 200 mmol/L of NaCl. The effects of NaCl stress on hypocotyl lengths and fresh weights of line 360-3 × 112-2 were less than other hybrids seedlings. Therefore, it had lower salt stress index and higher lethal salt concentration （ 134.72 mmoL/L）.