氯化钠胁迫对嫁接黄瓜叶片多胺含量的影响

以日本耐盐品种‘帝王新土佐’南瓜为砧木，以’新泰密刺’黄瓜为接穗，在100 mmol·L^-1 NaCl胁迫下，对黄瓜嫁接和自根植株不同时期叶片中不同形态多胺含量的变化进行了研究.结果表明：NaCl胁迫下黄瓜嫁接植株游离态腐胺（Put）含量在胁迫2 d时与自根植株无显著差异，其余时间均显著高于自根植株；游离态亚精胺（Spd）和游离态精胺（Spm）含量在整个胁迫期间均显著高于自根植株；游离态多胺总量（PAs）在胁迫第4天出现峰值；嫁接植株游离态Put/PAs值在胁迫4 d时与自根植株无显著差异，其余胁迫时间均显著低于自根植株，而(Spd+Spm)/Put值在整个胁迫期间均显著高于自根植株；嫁接植株结合态和束缚态Put、Spd和Spm含量在整个胁迫期间均显著高于自根植株，结合态和束缚态PAs在胁迫第6天出现峰值；结合态多胺的Put/PAs值和(Spd+Spm)/Put值变化趋势与游离态多胺一致；嫁接植株束缚态Put/PAs值在胁迫6 d时与自根植株无显著差异，其余时间均显著低于自根植株，而(Spd+Spm)/Put值在整个胁迫期间均显著高于自根植株.表明黄瓜嫁接植株表现出较强的耐盐特征.

Effects of NaCl stress on polyamine contents in grafted cucumber leaves.

With a Japanese salt-tolerant pumpkin cultivar 'King Shintosa' (Cucurbita maxima x C. moschata) as rootstock and a cucumber (Cucumis sativus) cultivar 'Xintaimici' as cion, this paper studied the temporal dynamics of different form polyamines contents in the leaves of grafted and own-rooted cucumber plants under 100 mmol x L(-1) NaCl stress. The results showed that the free putrescence (Put) content of graftedplant leaves (G2) was significantly higher than that of own-rooted plant leaves (O2), except on the second day of NaCl stress. During the whole period of NaCl stress, the free spermidine (Spd) and spermine (Spm) contents of G2 were significantly higher than those of O2, and the total free polyamine content of G2 peaked on the fourth day of stress. The free Put/PAs value of G2 was significantly lower than that of O2 except on the fourth day of stress, but (Spd + Spm)/Put value was significantly higher than that of O2 during the whole period of stress. In the test period, the contents of conjugated and bound Put, Spd, Spm of G2 were significantly higher than those of O2. The total conjugated and bound polyamine contents of G2 peaked on the sixth day of stress. Both conjugated Put/PAs and conjugated (Spd + Spm)/Put values had a similar changing trend to free polyamine. The bound Put/PAs value of G2 was significantly lower than that of O2 except on the sixth day of stress, while the bound (Spd + Spm)/Put value was significantly higher than that of O2 during the whole period of stress. All of these demonstrated that grafted cucumber plant possessed a stronger salt tolerance.