New Trichoderma Morphotypes for Southeastern Mexico

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Meloidogyne incognita is a sedentary endoparasitic nematode that parasitizes and causes damage to tropical vegetables, such as tomato (Solanum lycopersicum L.); synthetic chemical nematicides are used for its management. The objective of this study was to determine the effectiveness of Trichoderma morphotypes in controlling second-stage juveniles (J2s) in vitro, reducing M. incognita reproduction, and decreasing disease severity in creole tomato. Two experiments were conducted: 1) In vitro, culture medium filtrates from 10 Trichoderma morphotypes were evaluated against J2s, and mortality was assessed at 24 and 48 h; and 2) The in vitro active strains were evaluated against M. incognita in S. lycopersicum; each morphotype was considered a treatment, and a nematicide and a control were included in a completely randomized experimental design. After 35 days, the galling index (GI), the number of females (NF), and the number of eggs (NE) per gram of root, as well as agronomic variables, were evaluated. In vitro, the CAM43, CAM44, CAM49, and CAM50 morphotypes caused 100% mortality of J2s within 48 h of evaluation. The GI was reduced by 22.35% upon inoculation with the CAM43 morphotype. Trichoderma morphotypes reduced the NF by 57%, while CAM43 and CAM44 reduced the NE by 48.59%, showing superior control compared to the nematicide. Plants with the greatest height (60.93 cm) and dry leaf biomass (2.27) were obtained with CAM50, while the highest root dry weight was achieved with CAM43, with increases of up to 70.52% relative to the control. This study demonstrates that Trichoderma morphotypes from southeastern Mexico have the potential to control M. incognita in tomato.