In this study, Pseudomonas putida BSP9 isolated from rhizosphere of Brassica juncea was investigated for its plant growth promoting and biosurfactant producing activities. The isolate showed the ability to produce indole acetic acid, siderophore, phosphate solubilization activity and was an efficient producer of biosurfactant. Purification (of the biosurfactant) by thin layer chromatography (TLC) and further characterization by Fourier transform infrared spectroscopy (FTIR) revealed that biosurfactant produced by the isolate belonged to the glycolipid category, which is largely produced by Pseudomonas sp. In addition, liquid chromatography-mass spectroscopy (LC-MS) analysis showed the presence of a mixture of six mono-rhamnolipidic and a di-rhamnolipidic congeners, confirming it as a rhamnolipid biosurfactant. Bioformulations were developed using BSP9 and its biosurfactant to check their impact on promoting plant growth in B. juncea. It was noted from the study that bioformulations amended with biosurfactant (singly or in combination with BSP9) resulted in enhancement in the growth parameters of B. juncea as compared to untreated control. Maximum increment was achieved by plants inoculated with bioformulation that had BSP9 plus biosurfactant. The study also suggested that growth promotion was significant up to a threshold level of biosurfactant and that further increasing the concentration did not further enhance the growth parameter values of the plant. The study proves that novel bioformulations can be developed by integrating plant growth promoting rhizobacteria (PGPR) and their biosurfactant, and they can be effectively used for increasing agricultural productivity while minimizing our dependence on agrochemicals.

中文翻译：

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从恶臭假单胞菌BSP9开发的新型生物制剂及其生物表面活性剂，用于促进芥菜（L.）的生长

在这项研究中，研究了从芥菜根际分离的恶臭假单胞菌BSP9的植物生长促进作用和生物表面活性剂生产活性。该分离物显示出产生吲哚乙酸，铁载体，磷酸盐溶解活性的能力，并且是生物表面活性剂的有效生产者。通过薄层色谱（TLC）纯化（生物表面活性剂）并通过傅立叶变换红外光谱法（FTIR）进一步表征，发现分离物产生的生物表面活性剂属于糖脂类，其中大部分由假单胞菌产生sp。另外，液相色谱-质谱（LC-MS）分析显示存在六个单鼠李糖脂和二鼠李糖脂同系物的混合物，证实其为鼠李糖脂生物表面活性剂。使用BSP9及其生物表面活性剂开发了生物制剂，以检查它们对促进芥菜的生长的影响。从研究中注意到，用生物表面活性剂（单独或与BSP9组合）修正的生物制剂导致芥菜芽胞杆菌的生长参数提高与未处理的对照组相比。接种含BSP9和生物表面活性剂的生物制剂的植株可实现最大增量。研究还表明，在生物表面活性剂达到阈值水平之前，生长促进作用是显着的，进一步提高浓度并不能进一步提高植物的生长参数值。该研究证明，通过整合植物促生根瘤菌（PGPR）及其生物表面活性剂可以开发出新颖的生物制剂，它们可以有效地用于提高农业生产率，同时最大限度地减少我们对农药的依赖。