Khan Abdur Rashid, Ali Qurban, Ayaz Muhammad, Bilal Muhammad Saqib, Sheikh Taha Majid Mahmood, Gu Qin, Wu Huijun, Gao Xuewen
Key Laboratory of Monitoring and Management of Crop Diseases and Pest Insects, Department of Plant Pathology, College of Plant Protection, Nanjing Agricultural University, Ministry of Education, Nanjing 210095, China.
Key Laboratory of Food Quality and Safety of Jiangsu Province, State Key Laboratory Breeding Base Institute of Plant Protection, Jiangsu Academy of Agricultural Sciences, Nanjing 210014, China.
Biology (Basel). 2023 Jun 30;12(7):940. doi: 10.3390/biology12070940.
The interaction between plant and bacterial VOCs has been extensively studied, but the role of VOCs in growth promotion still needs to be explored. In the current study, we aim to explore the growth promotion mechanisms of cold-tolerant strains GBAC46 and RJGP41 and the well-known PGPR strain FZB42 and their VOCs on tomato plants. The result showed that the activity of phytohormone (IAA) production was greatly improved in GBAC46 and RJGP41 as compared to FZB42 strains. The in vitro and in-pot experiment results showed that the VOCs improved plant growth traits in terms of physiological parameters as compared to the CK. The VOCs identified through gas chromatography-mass spectrometry (GC-MS) analysis, namely 2 pentanone, 3-ethyl (2P3E) from GBAC46, 1,3-cyclobutanediol,2,2,4,4-tetramethyl (CBDO) from RJGP41, and benzaldehyde (BDH) from FZB42, were used for plant growth promotion. The results of the partition plate (I-plate) and in-pot experiments showed that all the selected VOCs (2P3E, CBDO, and BDH) promoted plant growth parameters as compared to CK. Furthermore, the root morphological factors also revealed that the selected VOCs improved the root physiological traits in tomato plants. The plant defense enzymes (POD, APX, SOD, and CAT) and total protein contents were studied, and the results showed that the antioxidant enzymes and protein contents significantly increased as compared to CK. Similarly, plant growth promotion expression genes ( and ) were significantly upregulated and the gene was downregulated as compared to CK. The overall findings suggest that both isolates and their pure VOCs positively improved plant growth promotion activities by triggering the antioxidant enzyme activity, protein contents, and relative gene expressions in tomato plants.
植物与细菌挥发性有机化合物（VOCs）之间的相互作用已得到广泛研究，但VOCs在促进生长方面的作用仍有待探索。在本研究中，我们旨在探究耐寒菌株GBAC46和RJGP41以及著名的植物根际促生细菌（PGPR）菌株FZB42及其VOCs对番茄植株的促生长机制。结果表明，与FZB42菌株相比，GBAC46和RJGP41中植物激素（IAA）的产生活性有显著提高。体外和盆栽实验结果表明，与对照相比，VOCs在生理参数方面改善了植物生长性状。通过气相色谱-质谱联用（GC-MS）分析鉴定出的VOCs，即来自GBAC46的2-戊酮、3-乙基（2P3E），来自RJGP41的1,3-环丁二醇、2,2,4,4-四甲基（CBDO），以及来自FZB42的苯甲醛（BDH），被用于促进植物生长。分隔板（I-板）和盆栽实验结果表明，与对照相比，所有选定的VOCs（2P3E、CBDO和BDH）均促进了植物生长参数。此外，根系形态因子还表明，选定的VOCs改善了番茄植株的根系生理性状。对植物防御酶（POD、APX、SOD和CAT）和总蛋白含量进行了研究，结果表明，与对照相比，抗氧化酶和蛋白含量显著增加。同样，与对照相比，植物促生长表达基因（和）显著上调，而基因下调。总体研究结果表明，分离菌株及其纯VOCs均通过触发番茄植株中的抗氧化酶活性、蛋白含量和相关基因表达，积极改善了植物的促生长活性。
