Diagnosis, pathogenicity and antibiosis of Trichoderma spp., in vitro, of Fusarium oxysporum, Rhizoctonia solani and Macrophomina phaseoli in beans, tomatillo and chili

Abstract

Commercial crops of beans, tomatoes and peppers

with symptoms of wilt and chlorosis were sampled

in Mochitlán, Apipilulco and Cocula, Gro.,

respectively; of the roots, was isolated, and

morphologically identified to Fusarium oxysporum

(Fo), Rhizoctonia solani (Rs) and Macrophomina

phaseolina (Mp), respectively. Its pathogenicity was

checked and the following treatments were

evaluated: 1) Control, 2) Trichoderma sp. (native to

the place of origin of the pathogen), 3) T.

asperellum (native to Santa Teresa, Gro.), 4) T.

virens (PHC®  RootMate®), 5) Trichoderma sp.

(FITHAN^MR) and 6) T. harzianum (PHC®  T-22®);

distributed completely randomly with 3 repetitions.

The experimental unit was a Petri dish with 15 mL

of PDA + the metabolites of the biocontroller,

which were extracted using the cellophane paper

technique. It was found that strains of Trichoderma

spp., evaluated in vitro exerted fungistatic effect on

Fo, Rs and Mp. Strains of T. harzianum (PHC®  T-

22®), Trichoderma sp. (^MRFITHAN) and T.

asperellum (native of Cocula, Gro.) were the most

effective because they inhibited 73.84, 50.48 y

78.29% growth miceliar of Fo, Rs and Mp,

respectively.