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作 者 ：李卫欣^1,2;陈贵林¹;任良玉¹;王鹏²

期 刊 ：应用生态学报 2008年 19卷 03期 页码：569-574

关键词：南瓜；

摘 要 ：选择19个不同类型南瓜品种，研究了300 mmol·L^-1 NaCl胁迫条件下，幼苗地上部和根系Na⁺、K⁺、Ca²⁺含量、Na⁺/K⁺、Na⁺/Ca²⁺、钠-钾和钠-钙运输选择性系数(S_Na⁺,K⁺和S_Na⁺,Ca²⁺值)的变化.结果表明：NaCl胁迫处理8 d后，不同品种南瓜幼苗Na⁺含量均明显增加，而K⁺含量下降，离子平衡被打破.青栗（Q₁）南瓜幼苗根系Na⁺含量、地上部Na⁺/K⁺、Na⁺/Ca²⁺、S_Na⁺,K⁺和S_Na⁺,Ca²⁺值均明显高于黑蜜南瓜（H₂）和黑籽南瓜（H₃）.不同品种南瓜幼苗体内Na⁺含量、地上部Na⁺/K⁺和Na⁺/Ca²⁺、S_Na⁺,K⁺和S_Na⁺,Ca²⁺值变化趋势与NaCI胁迫下不同品种南瓜幼苗盐害指数的结果基本一致,进一步验证了Q₁耐盐性强与NaCl胁迫下地上部Na⁺/K⁺、Na⁺/Ca²⁺、S_Na⁺,K⁺和S_Na⁺,Ca²⁺值较低以及K⁺、Ca²⁺含量较高有关；而H₂和H₃对盐敏感与NaCl胁迫下地上部Na⁺/K⁺、Na⁺/Ca²⁺、S_Na⁺,K⁺和S_Na⁺,Ca²⁺值较高，以及K⁺、Ca²⁺含量较低有关.

Abstract:With the seedlings of 19 pumpkin cultivars as test materials, this paper studied the variations of Na⁺, K⁺, Ca²⁺, Na⁺/K⁺, Na⁺/Ca²⁺, S_Na⁺,K⁺ and S_Na⁺,Ca²⁺ in their shoots and roots under the stress of 300 mmol NaCl·L^-1. The results showed that after an 8-day exposure to 300 mmol NaCl·L^-1, the Na⁺ content in the seedlings increased significantly while the K⁺ content decreased, resulting in the brokenness of ion balance. The root Na⁺ content, shoot Na⁺/K⁺ and Na⁺/Ca²⁺ ratios, and S_Na⁺,K⁺ and S_Na⁺,Ca²⁺ of Cucurbita moschata (Q₁) were significantly higher than those of C. maxima (H₂) and C. ficifolia (H₃). The variation tendency of these parameters of different pumpkin cultivars’ seedlings were nearly consistent with the salt injury index of the seedlings under NaCl stress, which further proved that the strong salttolerance of Q₁ was related to the lower values of shoot Na⁺/K⁺, Na⁺/Ca²⁺, S_Na⁺,K⁺ and S_Na⁺,Ca²⁺, and the high contents of K⁺ and Ca²⁺, while the saltsensitivity of H₂ and H₃ was related to the higher values of shoot Na⁺/K⁺, Na⁺/Ca²⁺, S_Na⁺,K⁺ and S_Na⁺,Ca²⁺, and low contents of K⁺ and Ca²⁺ under NaCl stress.

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