Plant defense activation and management of tomato root rot by a chitin-fortified Trichoderma/Hypocrea formulation

Abstract

Tomato root rot caused by Rhizoctonia solani is a major soilborne disease resulting in significant yield loss. The culture filtrates of six isolates of Trichoderma/Hypocrea species were evaluated for in vitro production of hydrolytic enzymes. Results demonstrated that all the six isolates were able to produce chitinase, β-1, 3 glucanase and protease in the range of 76-235 μmol GlcNAc min -1 mg -1 protein, 31.90-37.72 nmol glucose min -1 mg -1 proteins and 63.05-86.22 μmol min -1 mg -1 proteins, respectively. Trichoderma/Hypocrea-based formulation(s) were prepared with chitin (1% v:v) and CMC (0.5% w:v) for root rot management in a greenhouse. Root dip application with bioformulation(s) resulted in a significant reduction of the root rot index. In addition, bioformulations increased plant growth attributing traits significantly relative to untreated control. Accumulation of total phenols, peroxidase, polyphenoloxidase and phenylalanine ammonia lyase increased in chitin-supplemented Trichoderma/Hypocrea formulation-treated plants challenged with R. solani. The results suggest that chitin-fortified bioformulation(s) could be an effective system to control root rot of tomato in an eco-compatible manner.

Identification, characterization and phylogenetic analysis of antifungal Trichoderma from tomato rhizosphere

“…Several species of Trichoderma have been used as biological control agents to manage diseases of vegetable and other crops (Solanki et al 2011; Srivastava et al 2012; Al-Sadi et al 2015). In the present study, twenty isolates of Trichoderma collected from rhizosphere soil of tomato were phenotypically, biochemically and genetically characterized to identify and screen the most efficient antagonistic against four tomato fungal pathogens (FOL, AA, CG and RS).…”

“…They reported that the mycoparasitic capacity of various species and isolates of Trichoderma differs. There are several mechanisms involved in Trichoderma antagonism, namely, antibiosis whereby the antagonist fungus produces antibiotics, competes for nutrients and mycoparasitism, whereas Trichoderma directly attacks the plant pathogen by excreting lytic enzymes such as chitinases and β-1,3 glucanases (Kubicek et al 2001; Radjacommare et al 2010; Solanki et al 2011). Such hydrolytic enzymes partially degrade the pathogen cell wall that leads to parasitization (Howell 2003).…”

“…Some species of Trichoderma viz., Trichoderma harzianum , T. viride , T. virens and T. koningii are well known antagonists and are being utilized to control plant pathogens under field conditions (Solanki et al 2011; Srivastava et al 2012; Galarza et al 2015). Promising Trichoderma isolates have different mechanisms or combination of direct parasitism, competition for nutrients, stimulators of plant health, or inducers of plant systemic resistance against various pathogens (Harman et al 2004; Anees et al 2010; Woo et al 2014; Jain et al 2015; Rai et al 2016).…”

Advances in Formulation of Trichoderma for Biocontrol

“…Trichoderma asperellum has shown biocontrol potential against Fusarium head blight by using liquid media of differing composition (Kolombet et al, 2008). A chitin fortified bioformulation of Trichoderma/Hypocrea species allowed increased accumulation of total phenols, peroxidase, polyphenoloxidase and phenylalanine ammonia lyase in treated tomato plants when challenged with R. solani (Solanki et al, 2011). The biomass paste formulation remained viable for at least 6 months at room temperature (Kolombet et al, 2008).…”

Studies on Exo-Chitinase Production from Trichoderma asperellum UTP-16 and Its Characterization

“…The chitinolytic enzymes of microbial origins, especially exo-chitinases of Trichoderma spp. can restrict the growth of soil-borne pathogens through hydrolysis of cell wall associated chitin [3]. Chitinase production by T. harzianum was found to be induced using wheat bran-based solid medium containing 1% colloidal chitin and the chitinase lead to the lysis of the phytopathogenic fungus Colletotrichum gloeosporioides [4].…”