Department of Environmental Science, School of Earth and Environmental Sciences, Babasaheb Bhimrao Ambedkar University, Lucknow, 226025, India.
World J Microbiol Biotechnol. 2024 Aug 20;40(10):305. doi: 10.1007/s11274-024-04092-x.
In past few years, salinity has become one of the important abiotic stresses in the agricultural fields due to anthropogenic activities. Salinity is leading towards yield losses due to soil infertility and increasing vulnerability of crops to diseases. Fluorescent pseudomonads are a diverse group of soil microorganisms known for promoting plant growth by involving various traits including protecting crops from infection by the phytopathogens. In this investigation, salt tolerant plant growth promoting bacterium Pseudomonas hunanensis SPT26 was selected as an antagonist against Fusarium oxysporum, causal organism of fusarium wilt in tomato. P. hunanensis SPT26 was found capable to produce various antifungal metabolites. Characterization of purified metabolites using Fourier transform infrared spectroscopy (FT-IR) and liquid chromatography-electron spray ionization-mass spectrometry (LC-ESI/MS) showed the production of various antifungal compounds viz., pyrolnitrin, pyochelin and hyroxyphenazine by P. hunanensis SPT26. In the preliminary examination, biocontrol activity of purified antifungal metabolites was checked by dual culture method and results showed 68%, 52% and 65% growth inhibition by pyrolnitrin, 1- hydroxyphenazine and the bacterium (P. hunanensis SPT26) respectively. Images from scanning electron microscopy (SEM) revealed the damage to the mycelia of fungal phytopathogen due to production of antifungal compounds secreted by P. hunanensis SPT26. Application of bioinoculant of P. hunanensis SPT26 and purified metabolites significantly decreased the disease incidence in tomato and increased the plant growth parameters (root and shoot length, antioxidant activity, number of fruits per plant, etc.) under saline conditions. The study reports a novel bioinoculant formulation with the ability to promote plant growth parameters in tomato in presence of phytopathogens even under saline conditions.
在过去的几年中，由于人为活动，盐度已成为农业领域的重要非生物胁迫因素之一。盐度导致土壤贫瘠，作物对疾病的易感性增加，从而导致产量下降。荧光假单胞菌是一组多样化的土壤微生物，以通过涉及各种特性（包括保护作物免受植物病原体感染）来促进植物生长而闻名。在这项研究中，选择耐盐植物生长促进细菌 Pseudomonas hunanensis SPT26 作为番茄枯萎病的病原体尖孢镰刀菌的拮抗剂。发现 P. hunanensis SPT26 能够产生各种抗真菌代谢物。使用傅里叶变换红外光谱（FT-IR）和液相色谱-电子喷雾电离质谱（LC-ESI/MS）对纯化代谢物进行的表征表明，P. hunanensis SPT26 产生了各种抗真菌化合物，如吡咯霉素，pyochelin 和羟苯嗪。在初步检查中，通过双培养法检查了纯化抗真菌代谢物的生物防治活性，结果表明吡咯霉素，1-羟基苯嗪和细菌（P. hunanensis SPT26）分别抑制了 68％，52％和 65％的生长。扫描电子显微镜（SEM）的图像显示，由于 P. hunanensis SPT26 分泌的抗真菌化合物的产生，真菌植物病原体的菌丝受到了破坏。在盐胁迫条件下，P. hunanensis SPT26 的生物接种剂和纯化代谢物的应用可显著降低番茄的病害发生率，并增加植物生长参数（根和茎长，抗氧化活性，每株果实数等）。该研究报告了一种新型的生物接种剂配方，即使在盐胁迫条件下，该配方也具有在存在植物病原体的情况下促进番茄生长参数的能力。
