Native Trichoderma strains from Brazilian biomes exhibit dual activity: biocontrol of Sclerotinia sclerotiorum and growth promotion in common bean

Biological control using fungi of the Trichoderma genus has been gaining increasing prominence as a sustainable alternative to synthetic pesticides, particularly due to its ability to suppress phytopathogens and promote plant growth. While the beneficial role of Trichoderma species is well established, research involving native strains from Brazilian biomes remains limited. The present work comprised the investigation of 55 isolates of Trichoderma spp., isolated from the soil or endophytic from the plant species natives to the Pantanal and Cerrado of Mato Grosso do Sul (Brazil), regarding their capacity to inhibit the growth and spread of the phytopathogen Sclerotinia sclerotiorum (Lib.) de Bary. The results from confrontation assays (15.74–30.04% growth of S. sclerotiorum ), paired plate cultures (5.76–39.53% growth of S. sclerotiorum ), and cell wall-degrading enzyme (CWDEs) activity assays—whose activities ranged from 8.791–197.593 U·mg -1 for glucanase, 0.059–333.864 U·mg -1 for NAGase, 0.082–37.110 U·mg -1 for acid phosphatase, 1.234–45.716 U·mg -1 for chitinase, and 3.261–304.807 U·mg -1 for protease—were used to select Trichoderma spp. Five strains were selected: Trichoderma sp. T24, Trichoderma zelobreve T26, Trichoderma longibrachiatum T44, Trichoderma zelobreve T53, and Trichoderma sp. T55. Except for strain T44, all other strains demonstrated effectiveness in biological control of S. sclerotiorum (disease severity index ≤ 25%) and plant growth promotion in Phaseolus vulgaris L. cultivation (vigor index ≥ 268). The volatile organic compounds (VOCs) produced by five Trichoderma spp. strains post-exposure to S. sclerotiorum were analysed by Gas Chromatography-Mass Spectrometry (GC/MS) were identified, among these VOCs with known antifungal activity, such as β-cedrene (6), β-funebrene (7), and α-acoradiene (12). Trichoderma sp. T24, T. zelobreve T53, and Trichoderma sp. T55 have potential as biocontrol agents against S. sclerotiorum and as biostimulants, increasing plant growth and development. • Trichoderma spp. isolates from the Cerrado and Pantanal biomes combat white mold. • Dual functionality of Trichoderma spp. strains as both biocontrol agents and plant growth promoters. • Native species of Trichoderma suppressed S. sclerotiorum and promoted the growth of P. vulgaris. • Antifungal Trichoderma spp. strains produced VOCs β-funebrene, α-acoradiene, and β-cedrene with against S. sclerotiotum.