Grafting Cucumber Onto Pumpkin Induced Early Stomatal Closure by Increasing ABA Sensitivity Under Salinity Conditions
Grafting Cucumber Onto Pumpkin Induced Early Stomatal Closure by Increasing ABA Sensitivity Under Salinity Conditions
复制标题
将黄瓜嫁接到南瓜上通过增加盐度条件下的 ABA 敏感性诱导气孔早期关闭
DOI：
10.3389/fpls.2019.01290
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发表时间：
2019-11-11
影响因子：
5.6
通讯作者：
Bie, Zhilong
中科院分区：
文献类型：
--
作者：
Niu, Mengliang;Sun, Shitao;Bie, Zhilong
在盐胁迫的早期，气孔开度的减少可以防止水分流失和枯萎。脱落酸（ABA）信号在这一过程中起着重要作用。在这里，我们发现嫁接到南瓜上的黄瓜表现出快速的气孔关闭，这有助于植物适应盐分引起的渗透胁迫。研究了自嫁接和黄瓜嫁接两种嫁接方式对黄瓜根、木质部汁液和叶片中ABA含量的影响。研究了ABA生物合成或信号相关基因NCED2（9-顺式环氧类胡萝卜素双加氧酶基因2）、ABCG22 （atp结合盒转运基因22）、PP2C （2c型蛋白磷酸酶）和SnRK2.1（蔗糖非发酵1相关蛋白激酶2）的表达水平。结果表明，根源ABA信号导致嫁接植株气孔开度和蒸腾速率降低。此外，与自接黄瓜相比，嫁接到南瓜上的植株对ABA的敏感性增加。氟脲对ABA合成的抑制使叶片蒸腾速率和气孔导度增加。本研究表明，南瓜根部增加了接穗对从根部向茎部输送ABA的敏感性，增强了NaCl胁迫下的渗透耐受性。这种机制可以大大有利于蔬菜生产，特别是在半干旱盐碱区。
During early periods of salt stress, reduced stomatal opening can prevent water loss and wilting. Abscisic acid (ABA) signal plays an important role in this process. Here, we show that cucumber grafted onto pumpkin exhibits rapid stomatal closure, which helps plants to adapt to osmotic stress caused by salinity. Increased ABA contents in the roots, xylem sap, and leaves were evaluated in two grafting combinations (self-grafted cucumber and cucumber grafted onto pumpkin rootstock). The expression levels of ABA biosynthetic or signaling related genes NCED2 (9-cis-epoxycarotenoid dioxygenase gene 2), ABCG22 (ATP-binding cassette transporter genes 22), PP2C (type-2C protein phosphatases), and SnRK2.1 (sucrose non-fermenting 1-related protein kinases 2) were investigated. Results showed that a root-sourced ABA signal led to decreased stomatal opening and transpiration in the plants grafted onto pumpkin. Furthermore, plants grafted onto pumpkin had increased sensitivity to ABA, compared with self-grafted cucumbers. The inhibition of ABA biosynthesis with fluridon in roots increased the transpiration rate (Tr) and stomatal conductance (Gs) in the leaves. Our study demonstrated that the roots of pumpkin increases the sensitivity of the scion to ABA delivered from the roots to the shoots, and enhances osmotic tolerance under NaCl stress. Such a mechanism can be greatly exploited to benefit vegetable production particularly in semiarid saline regions.