In Vitro Antibacterial, Antifungal, Nematocidal and Growth Promoting Activities of Trichoderma hamatum FB10 and Its Secondary Metabolites

Abstract

Microbial natural biocides have attracted much more attention in recent years in order to avoid the unrestricted use of chemical biocides in the environment. The aim of this study is to analyze the antibacterial and antifungal activities of secondary metabolites and growth promoting, nematicidal, and soil enzyme activity mediated by Trichoderma hamatum FB10. The bactericidal and fungicidal activities were performed using cell-free extract. Results revealed that the selected strain exert antibacterial activity against Acidovorax avenae, Erutimacarafavora, and Xanthomonas campestris. The selected fungal strain FB10 showed antagonistic activity against fungal pathogens such as, S. sclerotiorum, Rhizoctonia solani, Alternaria radicina, Alternaria citri, and Alternaria dauci. Among the bacterial pathogens, A. avenae showed least MIC (30 ± 2.5 µg/mL) and MBC (70 ± 1.25 µg/mL) values. T. hamatum FB10 strain synthesized bioactive volatile secondary metabolite, which effectively inhibited the growth of bacteria and fungi and indicated the presence of 6-pentyl-alpha-pyrone as the major compound (67.05%). The secondary metabolite synthesized by T. hamatum FB10 showed nematicidal activity against M. incognita eggs. Egg hatch inhibition was 78 ± 2.6% and juvenile stage mortality rate was 89 ± 2.5% when the strain FB10 was treated with nematode. The cell free extract of T. hamatum FB10 showed protease, amylase, cellulase, chitinase, glucanase activities. T. hamatum FB10 inoculated with green gram increased 11% plant height, compared to the control. The fresh weight of the experimental group inoculated with T. hamatum FB10 increased 33.6% more compared to the control group. The green gram seedlings inoculated with T. hamatum FB10 increased 18% more dry weight than control group. Soil enzymes such as, urease, phosphatase, catalase and saccharase were improved in the soil inoculated with T. hamatum FB10. These biochemical components play potent role in soil fertility, energy conversion, and in soil organic matter conversion.

Trichoderma: The Current Status of Its Application in Agriculture for the Biocontrol of Fungal Phytopathogens and Stimulation of Plant Growth

“…Changes in the morphology of R. solanacearum cells (the rupturing of cell walls, the disintegration of the cell membrane, and leakage of cell contents) were observed as a result of the action of various secondary compounds from Trichoderma [165]. Moreover, T. hamatum synthesized the bioactive volatile secondary metabolite, 6PAP, which effectively inhibited the growth of Acidovorax avenae, Erutimacarafavora, and Xanthomonas campestris [167]. Sarsaiya et al [168] demonstrated for the first time that the endophytic strain of T. longibrachiatum, isolated from the medicine plant Dendrobium nobile, produced the dendrobine compound responsible for enhancing human immunity, preventing metastatic cancer, and therapeutic effects on Alzheimer's disease.…”

Protease Produced by Endophytic Fungi: A Systematic Review

“…Alkaline proteases could be used as bio-additive compounds in the textile and food industries and to increase cleaning power [36,42,43]. In this review, Li et al [24] and Lindstrom and Belanger [25] found fungal alkaline proteases of pH 9, 10, and 11, respectively, however, there was no assay for the application of these enzymes.…”

Efficacy of the biocontrol agent Trichoderma hamatum against Lasiodiplodia theobromae on macadamia

“…The fungal pathogen, L. theobromae strain L1, was originally isolated from a root of an infected macadamia tree growing in the same region. Both fungal isolates were identified based on their morphology and the nucleotide sequence of ITS rDNA ( Malachová et al, 2020 ; Baazeem et al, 2021 ). Specifically, the partial nucleotide sequences of ITS rDNA of the strain C9 ( Figure 1A ) and the strain L1 ( Figure 1B ) obtained in our study were 100% identical to those of T. hamatum isolate F4 (NCBI Accession: MT341773.1 ) and L. theobromae isolate FH14K03 (NCBI Accession: MK886711.1 ), respectively.…”