Serendipita indica as a Plant Growth Promoter and Biocontrol Agent against Black Rot Disease in Cabbage Grown in a Phytotron

Serendipita indica, a mutualistic root endophytic fungus, has gained attention for its potential to enhance plant health and resistance to various stresses. This study investigated the impact of S. indica (strain DSM 11827) on plant growth promotion and the management of black rot disease. This is a devastating bacterial ailment caused by Xanthomonas campestris pv. campestris, which affects cruciferous crops worldwide. The experiment was conducted under sterile conditions in a phytotron for 10 weeks. It involved the substrate and seed inoculation of S. indica in a cabbage crop. The findings suggested that S. indica establishes mutualistic relationships with cruciferous plants, positively influencing their growth while simultaneously reducing their susceptibility to black rot disease. Plant morphological and physiological parameters were enhanced by S. indica application. Additionally, bio stress markers were also enhanced in response to black rot disease. Moreover, disease severity was reduced by 27.9% and 18.8% in the substrate and seeds treated with S. indica, respectively. However, our findings did not report any antagonistic effect between S. indica and two pathogens, i.e., Xanthomonas campestris pv. campestris and Alternaria brassicicola under the in vitro test, suggesting that the suppression of black rot disease in cabbage seedlings was induced indirectly by S. indica. This study, therefore, underscores the promising prospect of utilizing S. indica to promote crop productivity and combat the destructive impact of black rot disease in cruciferous plants, contributing to more sustainable and resilient agriculture.