In-vivo biocontrol of Fusarium wilt in chilli plants using hypersaline Bacillus paralicheniformis strain MPSK23

Abstract

Abstract Fusarium solani is the causative mycopathogen for wilting in chilli plants across India and results in a substantial yield loss of chillies. The current study aims at evaluating the potential of a hypersaline Bacillus paralicheniformis strain MPSK23 in the control of Fusarium wilt and its effect on the growth of the infected plants. Co-inoculation of MPSK23 with Fusarium solani, exhibited 94% decrease in weight of the pathogen in liquid media. Usage of MPSK23 as a biocontrol agent resulted in significant increase in germination percentage (100%) and germination energy (73.33%) of chilli seeds of Khola and Sitara variety. The treatment also reduced the mean germination time by 3 days in Khola and 1.5 days in Sitara. Both the hypocotyl and the root length of the seedlings exhibited increase after the MPSK23 treatment, with the vigour index of seedlings being 25 times higher than the control. In-vivo inoculation of chilli seedlings of both the varieties, with MPSK23 resulted in a complete suppression of wilt in plants hence exhibiting highest protective value against the pathogen. Increment in the plant’s defense enzyme activities (Peroxidase, Phenylalanine ammonia-lyase, Polyphenol oxidase) along with total phenol content was also observed after treating with MPSK23. Similarly, the treated plants revealed better foliage, increase in total height of the plants and increase in the length and weight of roots and shoot. This study thus ascertains the role of Bacillus paralicheniformis strain MPSK23 as an effective and efficient biocontrol agent in the control of wilt in chilli plants.