Production of lytic enzymes by Trichoderma strains during in vitro antagonism with Sclerotium rolfsii, the causal agent of stem rot of groundnut

Abstract

Six Trichoderma strains (collected from IARI, New Delhi and MTCC, Chandigarh) were tested for their ability to inhibit soil-borne pathogen of groundnut mainly Sclerotium rolfsii (causing stem rot on groundnut). In vitro percent growth inhibition of S. rolfsii by various Trichoderma strains were recorded at 5 th day after inoculation (DAI). Results obtained from the antagonism study indicated that Trichoderma viride (NBAII Tv 23) inhibited 61% growth of phytopathogenic fungi S. rolfsii followed by Trichoderma harzianum (NBAII Th1) (55% growth inhibition of pathogen). The specific activities of cell wall degrading enzymes chitinase, β-1,3 glucanase, protease and cellulase were tested during different incubation period (48, 72 and 96 h) when Trichoderma spp. grew in the presence of pathogen cell wall in synthetic media. The antagonist T. viride (NBAII Tv 23) induced higher chitinase and protease activity. The growth inhibition of pathogen during antagonism were positively correlated with coiling pattern of antagonists at 14 th day after inoculation (DAI) as well as with the induction of chitinase, β-1,3 glucanase and total phenol content. However, the amount of cellulase and polygalacturonase recorded was least in these antagonists treatment. A significant positive correlation (p = 0.01) between percentage growth inhibition of test fungus and lytic enzymes (chitinase, β-1,3-glucanase and protease) in the culture medium of antagonist treatment established a relationship to inhibit growth of fungal pathogen by increasing the levels of these enzymes. Among all the tested Trichoderma strains, T. viride (NBAII Tv 23) was found to be the best strain to be used in biological control of plant pathogen S. rolfsii.

Diagnosis and Integrated Management of Fruit Rot in Cucurbita argyrosperma, Caused by Sclerotium rolfsii

“…produces enzymes (glucanases and chitinases), antibiotics (viridina, gliotoxin or peptaiboles) and mycotoxins (Shoresh and Harman, 2008), which are involved in the fungistatic effect Trichoderma produces against fungal pathogens such as S. rolfsii (Hirpara et al, 2017). The results obtained in the present experiment with T. virens are different to those reported by Parmar et al (2015), who studied, antibiosis of various Trichoderma strains in vitro in the biocontrol of S. rolfsii isolated from peanut. In which, 50% inhibition was obtained with T. virens .…”

Seed Biopriming With Trichoderma Strains Isolated From Tree Bark Improves Plant Growth, Antioxidative Defense System in Rice and Enhance Straw Degradation Capacity

“…Fungal biocontrol agents are popular as they may be reproduced easily in an artificial nutrient media and are suitable for commercial multiplication (Singh et al, 2013). Genus Trichoderma is compelling as a biocontrol operator against various pathogens (Parmar et al, 2015). The primary natural habitat of Trichoderma is traditionally seen as soil or plant rhizosphere, even though maximum diversity of these species happens over-the-ground (Druzhinina et al, 2011).…”

Mycolytic effect and underlying mechanism of Chaetomium subaffine LB‐1 on phytopathogenic fungi via morphological, physio‐biochemical and transcriptomic analysis

“…Production of cell wall hydrolase is often considered as an important way for biocontrol strain to exert its mycolytic effect (Parmar et al, 2015;Viterbo et al, 2002). It has been discovered that Trichoderma harzianum-1 (Ghosh et al, 2015), Streptomyces blastmyceticus JZB130180 (Ni et al, 2019), Bacillus methylotrophicus NJ13 F I G U R E 7 Homology alignment of strain LB-1 with other species according to annotated unigenes.…”