trichoderma species are among important antagonists of plant pathogenic fungi. the main purpose of this study was to evaluate the biocontrol potential of native trichoderma spp. isolates from sugar beet fields against phytophthora drechsleri and p. cryptogea, the causal agents of phytophthora root rot of sugar beet. during 2007–08, 85 isolates of trichoderma spp. from sugar beet fields in eight...

Fusarium graminearum Schwabe causes Fusarium head blight (FHB), a devastating disease that leads to extensive yield and quality loss of wheat and other cereal crops. Twelve isolates of F. graminearum were collected from naturally infected spikes of wheat from Assiut Egypt. These isolates were compared using SRAP. The results indicated distinct genetic groups exist within F. graminearum, and dem...

Fusarium head blight is one of the most severe diseases of small grain cereals and is caused by several toxigenic Fusarium species. Yield losses and mycotoxin accumulation in grain are caused by the disease. F. sporotrichioides and F. poae produce type A trichothecenes. Saprophyte fungal antagonists, especially Trichoderma harzianum, are effective biocontrol agents against several fungal soil-b...

The antigenic cross-reactivity between Treponema pallidum and several pathogenic members of the family Spirochaetaceae was examined by sodium dodecyl sulfate-polyacrylamide gel electrophoresis and Western blotting techniques. Blots of T. pallidum antigens were incubated with antiserum from rabbits infected or immunized with T. pallidum, Treponema paraluiscuniculi, Treponema hyodysenteriae (stra...

The dual culture of Trichoderma harzianum and Catharanthus roseus callus produced an antimicrobial compound with a remarkable activity against the Gram-positive bacteria Staphylococcus aureus and Bacillus subtilis. Structural elucidation revealed that this compound, which we have named trichosetin, is a novel tetramic acid (2,4-pyrrolidinedione) antibiotic and a homolog of the fungal metabolite...

When the mycoparasitic, biocontrol fungus Trichoderma harzianum was allowed to grow on nylon fibers treated with concanavalin A or Sclerotium rolfsii lectin, it coiled around the nylon fibers and produced hooks in a pattern similar to that observed with the real host hyphae. The incidence of interaction between T. harzianum and S. rolfsii lectin-treated fibers was significantly higher than that...

Trichoderma is one of the fungi genera that produce important metabolites for industry. The growth of these organisms is a consequence of the nutritional sources used as also of the physical conditions employed to cultivate them. In this work, the automated Bioscreen C system was used to evaluate the influence of different nutritional sources on the growth of Trichoderma strains (T. hamatum, T....

Twelve isolates of Trichoderma (six of T. harzianum, five of T. viride, one of T. virens), which reduced variably the incidence of collar rot disease caused in peanut by Aspergillus niger Van Tieghem, were evaluated for their potential to produce lytic enzymes during in vitro antagonism. T. viride 60 inhibited highest (86.2%) growth of test fungus followed by T. harzianum 2J (80.4%) at 6 days a...

Production of extracellular endochitinase could be increased 5-fold in the mycoparasite fungus Trichoderma harzianum by using the cellulase promoter cbh1 of Trichoderma reesei, whereas the total endochitinase activity increased 10-fold. The cbh1 promoter was not expressed on glucose and sucrose in T. harzianum and was induced by sophorose and on cellulase-inducing medium. The endogenous endochi...