Rootstocks improve cucumber photosynthesis through nitrogen metabolism regulation under salt stress
Rootstocks improve cucumber photosynthesis through nitrogen metabolism regulation under salt stress
复制标题
盐胁迫下砧木通过调节氮代谢提高黄瓜光合作用
DOI：
10.1007/s11738-013-1262-5
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发表时间：
2013-07-01
影响因子：
2.6
通讯作者：
Lei, Bo
中科院分区：
文献类型：
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作者：
Liu, Zhixiong;Bie, Zhilong;Lei, Bo
We examined the growth, photosynthetic parameters, initial and total ribulose-1,5-bisphosphate carboxylase/oxygenase (Rubisco) activity, the relative expression ofrbcL,rbcS, andrcagene, and nitrogen metabolism of cucumber (Cucumis sativusL. cv. Jinchun No.2, CS) plants grafted onto figleaf gourd (Cucurbita ficifoliaBouché, CF) and pumpkin (Cucurbita moschataDuch. cv. Chaojiquanwang, CM) rootstocks. Growth inhibition under salt stress (90 mM NaCl) was characterized by the irreversible inhibition of CO2assimilation in the cucumber plants grafted onto cucumber rootstocks (CS/CS). In contrast, this effect was significantly alleviated by grafting the cucumber plants onto the CF and CM roots (CS/CF, CS/CM). Under NaCl stress, the CS/CF and CS/CM plants exhibited higher photosynthetic activity, higher initial and total Rubisco activity, and higher Rubisco-related gene expression than the CS/CS plants. Salinity resulted in a lesser increase in nitrate content and decrease in free amino acid content in the CS/CF and the CS/CM plants compared with the CS/CS plants. Accordingly, the activity of nitrate reductase, glutamine synthetase, and glutamate synthase decreased significantly, especially in the CS/CS plants. These results suggest that grafting cucumber plants onto salt-tolerant rootstocks enhances Rubisco activity and the expression of Rubisco-related genes by effectively accelerating nitrate transformation into amino acids under NaCl stress, thereby improving the photosynthetic performance of cucumber leaves.
