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Plant‐growth‐promoting (PGP) endophytic bacteria are beneficial microorganisms that can help plants withstand biotic stress caused by fungal phytopathogens. In the present study, 78 endophytic bacterial isolates were isolated from chilli (Capsicum annuum L.). A potent isolate with several PGP attributes and better inhibition against Agroathelia rolfsii was selected and identified as Bacillus amyloliquefaciens using 16S rDNA homologies. Phosphate solubilization (65.9 μg ml−1), nitrogen fixation, production of IAA (9.77 to 24.45 μg ml−1), ammonia, ACC deaminase, siderophore, and hydrolytic enzymes were among the PGP traits shown by the strain SS_CR10. Furthermore, the strain demonstrated the ability to colonize roots. It significantly improved the plant's developmental traits, such as fresh and dry weight, photosynthetic pigments, and root and shoot length. LC–MS analysis and PCR amplification of lipopeptide genes also showed that surfactin, iturin, and bacilysin lipopeptides were present. Following treatments with lipopeptide extract and bacterial suspension, A. rolfsii mycelia showed severe deformation and cell death, as seen by live dead staining by fluorescent microscopy and scanning electron microscopy (SEM). Finally, the upregulation of defense‐related genes CaPR1, CaPR2, and CaPR4 after bacterial treatment confirmed the induction of systemic resistance. In conclusion, this study shows how strain SS_CR10 might be useful for promoting plant growth in chilli and controlling A. rolfsii in an eco‐friendly way, which would protect the health of the soil. [ABSTRACT FROM AUTHOR]

A severe outbreak of foot rot and head rot disease of cabbage was observed during September 2017 to November 2019 in major cabbage growing regions of southern Karnataka state of India. The disease incidence ranged between 3% and 28%. The initial symptoms were observed as tan, water‐soaked lesions at the point of infection and development of mycelia, followed by quick wilting of the whole plant. Subsequently, numerous sclerotia were produced. The pathogen isolated on PDA medium produced white fluffy aerial mycelia and numerous reddish‐brown sclerotia after 7−10 days. A total of 18 fungal isolates were used for mycelial compatibility analysis. Isolate SrBoC28 was used to test for pathogenicity on cabbage, marigold, chilli and brinjal plants. Typical disease symptoms on leaves, stem and roots were evident 5, 8 and 10 days' post‐inoculation respectively. The isolate was pathogenic on all tested hosts, and the identity was confirmed by re‐isolation and morpho‐cultural and molecular studies. The latter were based on amplification of ITS‐rDNA and phylogenetic analysis which showed 100% sequence similarity with reference sequences. The identity was confirmed as S. rolfsii. This is a well‐known pathogen and causes disease on various economically important crop plants. To date, there are no reports on the association between S. rolfsii and foot and head rot disease of cabbage in India and elsewhere. Thus, to the best of our knowledge, this is the first report of foot rot and head rot of cabbage caused by S. rolfsii in India. [ABSTRACT FROM AUTHOR]

The agar overlay TLC–bioautography is one of the crucial methods for simultaneous in situ detection and separation of antimicrobial metabolites of pharmaceutical interest. The main focus of this research relies on the dereplication of an antimicrobial metabolite coriloxin derived from mycoendophytic Xylaria sp. NBRTSB-20 with a validation of agar overlay TLC–bioautography technique. This polyketide metabolite coriloxin was purified by column chromatography, and its purity was assessed by HPLC, UPLC-ESI-QTOF-MS, FT-IR and NMR spectral analysis. The antimicrobial capability of ethyl acetate extract and the purified compound coriloxin was determined by disc diffusion, minimal inhibitory concentration and agar overlay TLC–bioautography assay. The visible LOD of coriloxin antimicrobial activity was found at 10 μg for Escherichia coli and 20 μg for both Staphylococcus aureus and Fusarium oxysporum. Inter- and intra-day precision was determined as the relative standard deviation is less than 6.56%, which proved that this method was precise. The accuracy was expressed as recovery, and the values were found ranging from 91.18 to 108.73% with RSD values 0.94–2.30%, respectively. The overall findings of this investigation suggest that agar overlay TLC–bioautography assay is a suitable and acceptable method for the in situ determination of antimicrobial pharmaceuticals. [ABSTRACT FROM AUTHOR]