Pseudomonas koreensis culture filtrate alleviates tomato drought stress: modulation of antioxidant systems coupled with the porphyrin and chlorophyll–photosynthesis–fructose and mannose axis

• Published in: Plant and soil 2023-03, Vol.484 (1-2), p.237-256
• Main Authors: Guo, Qiao, Sun, Chenyu, Jing, Yuexi, Yang, Shanshan, Li, Haiyang, Xue, Quanhong, Lai, Hangxian
• Format: Article
• Language: English
• Subjects: Agriculture; Analysis; Antioxidants; Biomedical and Life Sciences; Biosynthesis; Catalase; Cell culture; Chlorophyll; Crop growth; Diseases and pests; Drought; Droughts; Ecology; Filtrate; Flavonoids; Fructose; Glutathione; Growth; Identification and classification; Influence; Leaves; Life Sciences; Mannose; Metabolism; Metabolites; Metabolomics; Moisture content; Peroxidase; Photosynthesis; Physiology; Plant growth; Plant Physiology; Plant Sciences; Plants (botany); Porphyrins; Pseudomonas; Pseudomonas koreensis; Research Article; Seedlings; Soil Science & Conservation; Solanum lycopersicum; Tomatoes; Transcriptomics; Water content
• ISSN: 0032-079X; 1573-5036
• DOI: 10.1007/s11104-022-05786-7

Aims Drought stress affects crop growth and productivity by causing morphological, physiological, and molecular changes. Pseudomonas koreensis is a plant-growth-promoting rhizobacterium that has potential for inducing stress tolerance in crops; however, the underlying mechanisms remain unclear. Therefore, this study verified the effects of P. koreensis on drought stress in tomato ( Solanum lycopersicum Mill.) and explored the associated mechanisms. Methods Tomato seedlings that were exposed to the cell-free culture filtrate of P. koreensis GS or not were grown under non-stressed and drought-stressed conditions. Plant and leaf samples subjected to integrated physiological, transcriptomic, and metabolomic analyses. Results Under drought stress, treatment with cell-free culture filtrate prominently increased plant height (7.7%), root length (17.2%), dry biomass (19.8%), relative water content (19.2%), leaf chlorophyll content (13.6%), and net photosynthesis rate (56.5%) in tomato. The culture filtrate treatment also enhanced catalase and peroxidase activity but decreased malondialdehyde content in drought-stressed leaves. Many differentially expressed genes and accumulated metabolites associated with antioxidant defense were enriched in flavonoid biosynthesis, glutathione metabolism, porphyrin and chlorophyll metabolism, photosynthesis, and fructose and mannose metabolism, which jointly contributed to the alleviation of drought stress. Conclusions The enhancement of plant antioxidant capacity is the key factor for P. koreensis GS cell-free culture filtrate in alleviating drought stress in tomato.