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Analysis of phenazine for fifteen pigment-producing Fusarium oxysporum f. sp. ciceris (Foc) antagonistic rhizobactria, ranged between 20.5 and 706.4 μg/mL, with the maximum production recorded by the isolate Ps45. Similarly, isolate Ps45 exhibited the highest values of phenazine-1-carboxylic acid (PCA) and 2-hydroxy-phenazine carboxylic acid (2-OH-PCA) concentration (268.1 and 44.4 μg/mL, respectively), whereas isolate Ps44 exhibited the highest hydroxy phenazine-dioxide (OH-P-dioxide) or iodinin concentration (621.2 μg/mL). In 10 pseudomonads, phz CD genes were marked for their capability to synthesize PCA. Thin layer chromatography (TLC) and high-performance liquid chromatography (HPLC) of five potential phenazines producers showed coloured spots with the same mobility and Rf value with the standard phenazine and a typical peak maxima at 247 nm. The highest phenazine concentration (612.1 μg/mL) was recorded by isolate Ps44. Scanning electron microscopic(SEM) evaluation of the crude phenazine extract of potential isolates disclosed disrupting and dwindling effects on the hyphal growth of selected virulent strain of Foc hyphal growth.

Background: Phytophthora blight (PB), caused by Phytophthora drechsleri f. sp. cajani, is soil borne disease of pigeonpea (Cajanus cajan L). The use of PGPR in agriculture leads to alternative disease management of crop in a sustainable ecofriendly way. Methods: In vitro and In vivo experimentation was conducted at fields of Punjab Agricultural University, Ludhiana during kharif season of 2017-18 to study the percentage of blight inhibition by rhizobacteria and production potential in pigeonpea. The present study consisted of 6 treatments of dual inoculation of antagonistic bacteria with recommended rhizobium of PAU (LAR-06).Results: The selected rhizoisolates were studied against Phytophthora drechsleri caused stem blight of pigeonpea. The allelochemicals and Plant Growth Promoting Rhizobacteria traits involved in antagonistic behavior significantly inhibited the growth of the test fungus. Scanning electron microscopy between potential rhizoisolates and test fungus revealed intumescent hyphae with irregular cell surface morphology. The synergistic effects of LAR-06 + S-2 and LAR-06+ S-18 were found to be the most potent ones in inhibiting the radial growth of the test pathogen with increased yield production in the field as well as greenhouse conditions.

Soil management today is dominated by toxic chemical fertilizers that pose a serious health and environmental risk. Beneficial soil microbes play a promising role in sustainable agriculture when used as biofertilizers. Pigeonpea (Cajanus cajan) is an ancient protein-rich leguminous pulse in India. Twelve different locations in Punjab (India) provided rhizospheric soil samples and the growth rates of 35 isolates were assessed at various temperatures. To identify potential plant growthpromoting traits with antifungal properties, morphological and biochemical characterization were carried out. Compared to uninoculated pigeonpea seeds, inoculated seeds with rhizoisolates showed a significant increase in growth parameters in greenhouse pot conditions. Plant growth-promoting rhizobacteria (PGPRs) are a good way to increase crop yields while also controlling disease outbreaks.