Genetic Characterization of Trichoderma spp. Isolated from Different Locations of Menoufia, Egypt and Assessment of their AntagonisticAbility

Trichoderma has been used as a biocontrol agent against soil borne diseases that cause economic losses for crops. The objectives of the present investigation were (i) to isolate and characterize Trichoderma spp. from Menoufia Governorate and (ii) to evaluate the isolated Trichoderma spp. as potential biocontrol agents against some soil borne diseases. Soil samples were collected from nine districts and 25 isolates were obtained. Methods of identification of macroscopic and microscopic features, and the sequences of ITS and TEF1-α yielded three species; T. harzianum, T. longibrachiatum and T. asperellum. Phylogenetic tree of the identified 22 strains confirmed that the two strains T. longibrachiatum and T. asperellum came together in the same branch while the rest of the strains which were T. harzianum were on the other side of the tree. All 25 Trichoderma strains and isolates exhibited inhibition to the mycelial growth of four pathogenens. They were antagonized by competition mechanism against 000v m Sclerotium spp., by antibiosis against Fusarium oxysporum and partially against Sclerotium spp. and by mycoparasitism against Rhizoctonia solani. Also, they elucidated differences in total chitinolytic activity measured by two different methods and exochitonolytic activity. Finally, no correlation was found between total chitinolytic activities and total protein contents.