Major secondary metabolites produced by two commercial Trichoderma strains active against different phytopathogens

Abstract

Aims: Trichoderma harzianum strains T22 and T39 are two micro‐organisms used as active agents in a variety of commercial biopesticides and biofertilizers and widely applied amongst field and greenhouse crops. The production, isolation, biological and chemical characterization of the main secondary metabolites produced by these strains are investigated. Methods and Results: Of the three major compounds produced by strain T22, one is a new azaphilone that shows marked in vitro inhibition of Rhizoctonia solani, Pythium ultimum and Gaeumannomyces graminis var. tritici. In turn, filtrates from strain T39 were demonstrated to contain two compounds previously isolated from other T. harzianum strains and a new butenolide. The production of the isolated metabolites was also monitored by liquid chromatography/mass spectrometry during in vitro interaction with R. solani. Conclusions: This paper reports the isolation and characterization of the main secondary metabolites obtained from culture filtrates of two T. harzianum strains and their production during antagonistic interaction with the pathogen R. solani. Significance and Impact of the Study: This is the first work on secondary metabolites produced by the commercially applied strains T22 and T39. Our results provide a better understanding of the metabolism of these fungi, which are both widely used as biopesticides and/or biofertilizers in biocontrol.

Antagonistic and Biocontrol Potential of Trichoderma asperellum ZJSX5003 Against the Maize Stalk Rot Pathogen Fusarium graminearum

“…Trichoderma spp., also secrete a chemically diverse range of secondary metabolites, including peptaibols, polyketides, pyrones, terpenes, and polypeptides [27,28]. A previous study reported on the significance of secondary metabolites in the antagonistic action of Trichoderma spp., against the pathogenic fungi Pythium ultimum and Rhizoctonia solani [10,29]. We also found that Trichoderma produced a diverse group of metabolites that were species-specific.…”

“…Secondary metabolites were extracted from culture filtrates of Trichoderma as previously described [10]. The selected Trichoderma (spore suspension 4.7 9 10 3 CFU/ml) was cultured in one liter of a mineral medium containing (g l -1 of 50 % seawater) peptone (10), glucose (5), MgSO 4 , NH 4 NO 2 (2.4), yeasts extracts (5), ZnSO 4 (0.2), FeSO 4 (0.2) at pH 7.2 and incubated at 28°C with shaking at 180 rpm for 31 days.…”

“…Production of peptaibols, a class of non-ribosomally synthesised linear peptides with antimicrobial properties by Trichoderma virens (Miller, Giddens and Foster) Arx and cloning of the gene responsible for its production has been established [9]. Numbers of studies dedicated to biological control of plant pathogens by Trichoderma, [10] have identified the production of secondary metabolites such as T22-azaphilone, harzianolide and T39 butenolide inhibitory to the R. solani (Teleomorph: Thanatephorus spp. ), P. ultimum and G. graminis var.…”

Natural hydroxyanthraquinoid pigments as potent food grade colorants: an overview

“…The detection of emodin-glycosides and physcionglycosides was also pointed from a strain of Dermocytes spp. 98 Strains of Trichoderma aureoviride 99 and T. harzianum 29,100 were found to produce yellow pigment pachybasin (group E 3 ) and also the orange-red pigment chrysophanol (group A 1 ). Both species of Trichoderma polysporum and T. viride 99,101,102 can also produce pachybasin in addition to the emodin and chrysophanol pigments.…”

The Effectivity of Trichoderma Strains in the Protection of Cucumber and Lettuce Against Rhizoctonia Solani

“…They grow on the surface of roots, where then may protect plants against pathogens and enhance growth. Knowledge concerning the behavior of these fungi as antagonists is essential for their effective use, because they can act against pathogen in several ways (Fravel 1988, Howell 1998, Altomare et al 1999, Harman et al 2004, Vinale et al 2006, Degenkolb et al 2006.…”