Wyniki wyszukiwania

Sortuj według:

Ogranicz wyniki do:

Effects of salt-tolerant rootstock grafting on ultrastructure, photosyntetic capacity, and H2O2-scavening system in chloroplasts of cucumber seedling under NaCl stress

100%

Zhen A., Bie Z., Huang Y., Liu Z., Lei B.

Acta Physiologiae Plantarum

2011

tom 33

nr 6

Plant growth, photosynthetic parameters, chloroplast ultrastructure, and the ascorbate-glutathione cycle system in chloroplasts of self-grafted and rootstock-grafted cucumber leaves were investigated. Grafted plants were grown hydroponically and were exposed to 0, 50, and 100 mM NaCl concentrations for 10 days. Under NaCl stress, the hydrogen peroxide (H₂O₂) content in cucumber chloroplasts increased, the chloroplast ultrastructure was damaged, and the gas stomatal conductance, intercellular CO₂ concentration, as well as shoot dry weight, plant height, stem diameter, leaf area, and leaf relative water content were inhibited, whereas these changes were less severe in rootstock-grafted plants. The activities of ascorbate peroxidase (APX; EC 1.11.1.11), glutathione reductase (GR; EC 1.6.4.2), and dehydroascorbate reductase (DHAR EC 1.8.5.1) were higher in the chloroplasts of rootstock-grafted plants compared with those of self-grafted plants under 50 and 100 mM NaCl. Similar trends were shown in leaf net CO₂ assimilation rate and transpiration rate, as well as reduced glutathione content under 100 mM NaCl. Results suggest that rootstock grafting enhances the H₂O₂-scavenging capacity of the ascorbate–glutathione cycle in cucumber chloroplasts under NaCl stress, thereby protecting the chloroplast structure and improving the photosynthetic performance of cucumber leaves. As a result, cucumber growth is promoted.

Rootstocks improve cucumber photosynthesis through nitrogen metabolism regulation under salt stress

86%

Liu Z., Bie Z., Huang Y., Zhen A., Niu M., Lei B.

Acta Physiologiae Plantarum

2013

tom 35

nr 07

We examined the growth, photosynthetic parameters, initial and total ribulose-1,5-bisphosphate carboxylase/ oxygenase (Rubisco) activity, the relative expression of rbcL, rbcS, and rca gene, and nitrogen metabolism of cucumber (Cucumis sativus L. cv. Jinchun No.2, CS) plants grafted onto figleaf gourd (Cucurbita ficifolia Bouche´, CF) and pumpkin (Cucurbita moschata Duch. cv. Chaojiquanwang, CM) rootstocks. Growth inhibition under salt stress (90 mM NaCl) was characterized by the irreversible inhibition of CO2 assimilation 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 Rubiscorelated 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.

Ograniczanie wyników

2 Acta Physiologiae Plantarum

2 Bie Z.

2 Huang Y.

2 Lei B.

2 Liu Z.

2 Zhen A.

1 Niu M.

1 2013

1 2011

Wyniki wyszukiwania

Effects of salt-tolerant rootstock grafting on ultrastructure, photosyntetic capacity, and H2O2-scavening system in chloroplasts of cucumber seedling under NaCl stress

Rootstocks improve cucumber photosynthesis through nitrogen metabolism regulation under salt stress