Abstract

The antagonist effects of thirty one Trichoderma strains isolated from different regions of México onPhytophthora capsici Leonian were evaluated.  In this study, both fungal species were confronted on petri dishes with agar-potato-dextrose (PDA) medium. Thirteen out of thirty one Trichoderma strains showed a good competition level, covering the petri dish area completely. Volatile compounds were observed in twenty four out of thirty one Trichoderma strains which inhibited to P. capsici in a range from 4.3 to 48.8%. In addition, it was observed that the supernatant of fourteen out of thirty one Trichoderma strains showed inhibitory effects on P. capsici.  Thirteen of the fourteen Trichoderma strains were identified at the specie level using sequencing of 18S rDNA.  Eleven of those strains were identified as T. asperellum, one as T. hamatum and one as T. rossicum.

Key works: Trichoderma, antagonist, antibiosis, volatile compounds.