In vitro toxicity of tropical Mexican micromycetes on infective juveniles of Meloidogyne incognita.

Culture filtrates and mycelia extracts (methanol and ethyl acetate) from nine selected Mexican tropical fungal strains were tested against second stage juveniles (J 2 ) of Meloidogyne incognita , in vitro conditions. The micromycetes Acremonium kiliense TA31, Aspergillus sp. 2XA5, Gliocladium sp. MR41, Selenosporella sp. MR26, Stagonospora sp. TA34, and four unidentified strains (TA13, 2TA6, 2TA7, and 2XA7) were cultured on Czapeck-Dox medium for 14 days and mycelial mat was separated by filtration for metabolites extraction. Aspergillus sp. 2XA5 and Selenosporella sp. MR26 showed the highest nematotoxic activity both in culture filtrates (100% mortality) and methanol extracts (> 90% mortality). The lowest EC 50 (0.08 mg mL -1 ) was exhibited by the methanol extract of the unidentified strain 2XA7. The results obtained indicate that tropical mycobiota have potential as biological control agents of plant parasitic nematodes.