Na2CO3处理对黄瓜嫁接苗与自根苗耐盐性的影响

通过Na2CO3，胁迫对黄瓜嫁接苗和自根苗耐盐性差异的研究，揭示黄瓜幼苗的耐盐机制，为设施黄瓜生产提供理论依据。实验以孝感早瓠瓜为砧木，津春四号黄瓜为接穗，采用不同浓度Na2CO3，溶液对黄瓜嫁接苗和自根苗进行处理，研究其对黄瓜幼苗的生理胁迫效应。结果表明：在0—7000mg／L范围内，随着Na2CO3，处理浓度的增加，黄瓜嫁接苗和自根苗的株高、茎粗、叶面积、地上部鲜重、根鲜重、叶绿素和根系活力均下降，但嫁接苗受抑制的程度显著低于自根苗；脯氨酸、丙二醛和根冠比均呈上升趋势，且这三项指标均表现为嫁接苗显著高于自根苗；叶片SOD酶活性均呈先上升后下降趋势，均在Na2CO3，处理浓度为1000mg／L时达到最大值，且嫁接苗的活性显著高于自根苗。嫁接苗的耐盐性优于自根苗，Na2CO3胁迫条件下，嫁接苗和自根苗的生长条件盐浓度以不超过3000mg／L为宜。

Effect of Na2CO3 Treatment on Salt Tolerance of Grafted and Self-rooted Cucumber Seedlings

In order to provide a theoretical basis for protected cucumber culture, the salt tolerance difference of grafted and self-rooted cucumber seedlings under the stress of Na2 CO3 was investigated. A gourd （Lagenaria sicerania var clavata Makino） named Xiao Gan Zao was used as rootstock and cucumber（var. Jin Chun No. 4） was used as scion in this experiment. Different concentration of Na2 CO3 was used to treat grafted and seff-rooted cucumber for examining salt tolerance effect. The results indicated that all of plant height, stem width, leaf area, shoot fresh weight, root fresh weight, chlorophyll content and root activity dropped as the treatment concentration of Na2CO3 increased from 0 mg/L to 7 000 mg/L, but there was significantly lower restriction to grafted cucumber seedlings than to self-rooted ones. The content of proline, MDA and shoot/root ratio rose, these three indices of grafted cucumber seedlings were significantly higher than that of self-rooted ones. SOD enzyme activity increased and then fell with the Na2 CO3 treatment concentration increased with apex at concentration of 1 000 mg/L, it was significantly higher in grafted cucumber leaves than that of self-rooted. The salt tolerance of grated cucumber was better than that of self-rooted cucumber seedlings. The grafted cucumber and self-rooted cucumber grew normally below the concentration of 3 000 mg/L of Na2CO3 stress.