Background

The biological control of phytopathogens is improved by incorporating native strains of biocontrol agents; this is the case of Trichoderma spp. The control effect is higher when are applied groups of organisms and show incompatible interactions with increase antagonism.

Objective

The objective of the present study was to identify and evaluate in vitro the interspecific relation of native Trichoderma spp., and the antagonistic effect of incompatible species against Meloidogyne incognita.

Methods

The isolates of Trichoderma spp. were evaluated among them in dual culture, 45 dual cultures were performed, the four with greater incompatibility: T. virens (Th27-08) /T. harzianum (Th33-59), T. citrinoviride (Th33-58) /T. harzianum (Th33-59), T. virens (Th43-13) /T. ghanense (Th26-52) y T. simmonsii (Th09-06) /T. harzianum (Th33-59) and were evaluated against M. incognita in Solanum lycopersicum, in greenhouse.

Results and conclusions

The results showed interactions incompatible with significant differences (P≤0.01) against the nematode in relation to the control without fungal inoculants, reductions of 50.8-83.0% in the severity of the radical damage were estimated, 25.7-80.3% in the number of eggs and 31.5-94.1% in the number of females. The best effect was observed in the confrontation of T. citrinoviride (Th33-58) /T. harzianum (Th33-59) when compared to the Oxamil 24% control.