【摘要】 采用19个不同类型南瓜品种,研究了300mmol/LNaCl下,幼苗地上部和根系Na+、K+离子含量、Na+/K+比值的变化。结果表明,NaCl胁迫8d后,不同南瓜品种幼苗Na+含量均明显增加,而K+含量下降,离子平衡被打破。南瓜幼苗体内的Na+含量、地上部的Na+/K+比值的变化反映植物对盐离子和营养元素相对的吸收情况。青栗(Q1)南瓜幼苗根系Na+含量、地上部Na+/K+比值明显高于黑蜜南瓜(H2)和黑子南瓜(H3)。不同南瓜品种幼苗体内Na+含量、地上部Na+/K+比值变化趋势与NaCl胁迫下不同南瓜品种幼苗的盐害指数的结果基本一致。进一步验证了Q1耐盐性强与盐胁迫下地上部Na+/K+比值较低,K+离子含量较高有关;而品种H2和H3对盐敏感与盐胁迫下地上部Na+/K+比值较高,K+离子含量较低有关。更多还原

【Abstract】 Variations of Na+, and K+ content, the ratios of Na+/K+ in shoot and root of seedlings in 19 pumpkin cultivars were investigated after an 8-day exposure to 300 mmol/L NaCl. The results showed that the content of Na+ significantly increased while K+ content decreased, then the ion balance was broken. The relative absorption of salt ions and nutritional elements were reflected in the variations of Na+ content and the ratios of Na+/ K+. Na+ content in root and the ratios of Na+/ K+ in shoot in Q1 (Qingli) were significantly higher than those in H2 (Heimi pumpkin), H3 (Cucurbita ficifolia). From these results, it could be inferred that the variation tendency of Na+ content and the ratios of Na+/ K+ in shoot of different pumpkin cultivar seedlings were nearly in consistent with the salt injury index of those under NaCl stress. This further proved that strong salt-tolerance of Q1 was related to the low ratios of Na +/ K+ in shoot and the high content of K+ ions under salt stress. The sensitivity of H2 and H3 to salt was connected with the high ratios of Na+/ K+ in shoot, and the low content of K+ ions under salt stress.更多还原