Reciprocal grafting between cucumber and pumpkin demonstrates the roles of the rootstock in the determination of cucumber salt tolerance and sodium accumulation
Reciprocal grafting between cucumber and pumpkin demonstrates the roles of the rootstock in the determination of cucumber salt tolerance and sodium accumulation
复制标题
黄瓜和南瓜之间的相互嫁接证明了砧木在黄瓜耐盐性和钠积累的测定中的作用
DOI：
10.1016/j.scienta.2012.04.018
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发表时间：
2013-01-04
影响因子：
4.3
通讯作者：
Wang, Baitian
中科院分区：
文献类型：
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作者：
Huang, Yuan;Bie, Zhilong;Wang, Baitian
利用砧木是通过降低钠毒害来提高黄瓜耐盐性的有效策略。然而，嫁接黄瓜植株较高的耐盐性和较低的Na+浓度的机制尚不清楚。本研究以南瓜(Cucurbita Moschata Duchene)和黄瓜(Cucurbita Moschata Duchene)为试材，分别对黄瓜和南瓜、南瓜和南瓜、南瓜和南瓜嫁接的6个组合进行了1 mM和91 mM盐胁迫处理。测定了盐处理后第10天和第30天的植株生长和Na+浓度。结果表明，当植株暴露在91 mM的氯化钠溶液中10d时，嫁接在南瓜上的黄瓜新梢生长减少量(29%)低于自嫁接黄瓜(58%)。同时，黄瓜嫁接南瓜的减少量(44%)高于自嫁接南瓜(27%)。嫁接到南瓜上的黄瓜地上部Na+浓度比自接黄瓜下降了69%，而嫁接到黄瓜上的南瓜地上部Na+浓度比自嫁接南瓜增加了203%。定量分析表明，南瓜根对Na+的排斥率为50.5%，而黄瓜对Na+的排斥率几乎为零。南瓜根植株的地上部Na+存留量平均下降了15.9%，而黄瓜根植株则未观察到Na+存留量。91 mM盐胁迫30d后，南瓜砧木木质部汁液中Na+的平均浓度由砧木的6.5 mM下降到接穗的1.9 mM，下降了71%。然而，以黄瓜为砧木时，嫁接结合并不是Na+转运的障碍。这些结果表明，南瓜砧木具有较高的Na+排斥和Na+保持能力，从而减少了Na+向地上部的运输，提高了黄瓜的耐盐性。此外，黄瓜耐盐性所需的从砧木到接穗的Na+转运减少，主要是由砧木驱动的。(C)2012爱思唯尔B.V.保留所有权利。
The use of rootstock is a valid strategy in increasing cucumber salt tolerance by reducing sodium toxicity. However, the mechanism responsible for higher salt tolerance and lower Na+ concentration in the shoot of grafted cucumber plants remains unclear. In this study, six combinations of cucumber (Cucumis sativus L., salt sensitive) and pumpkin (Cucurbita moschata Duchesne, salt tolerant): namely, ungrafted cucumber and pumpkin, self-grafted cucumber and pumpkin cucumber grafted onto pumpkin, and pumpkin grafted onto cucumber, were exposed to 1 or 91 mM NaCl. The plant growth and Na+ concentrations were measured at day 10 and day 30 after NaCl treatment. The results showed that when plants were exposed to 91 mM NaCl for 10 days, the shoot growth reduction in cucumber grafted onto pumpkin (29%) was lower than that in self-grafted cucumber (58%). Meanwhile, the reduction in pumpkin grafted onto cucumber (44%) was higher than that in self-grafted pumpkin (27%). The Na+ concentration in the shoot of cucumber grafted onto pumpkin decreased by 69% compared with self-grafted cucumber, whereas the Na+ concentration in the shoot of pumpkin grafted onto cucumber increased by 203% compared with self-grafted pumpkin. Quantitative analysis revealed that the pumpkin roots excluded 50.5% of Na+, whereas nearly no Na+ exclusion was observed, in the cucumber roots. The Na+ retention of plants with pumpkin roots decreased by an average of 15.9% in the shoot, whereas no retention of Na+ was observed in the plants with cucumber roots. When the plants were exposed to 91 mM NaCl for 30 days, the average Na+ concentration in the xylem sap of plants With pumpkin rootstocks decreased from 6.5 mM in the rootstock to 1.9 mM in the scion, decreased by 71%. However, the graft union was not a barrier for Na+ transport when the cucumber was used as rootstock. These results suggest that pumpkin rootstock had higher capacity for Na+ exclusion and Na+ retention, which resulted in reduced Na+ transport to the shoot and increased the salt tolerance of cucumber. In-addition, the decreased Na+ transport from rootstock to scion, which is required for cucumber salt tolerance, is primarily driven by the rootstock. (C) 2012 Elsevier B.V. All rights reserved.