Submitted to: Phytopathology
Publication Type: Abstract Only
Publication Acceptance Date: September 8, 1998
Publication Date: N/A
Technical Abstract: Several Trichoderma virens (Gliocladium virens) strains have good biocontrol activity against Rhizoctonia solani on cotton seedlings but lack some of the commercially desirable characteristics found in other Trichoderma species. In an attempt to consolidate desirable characteristics, we used a highly effective biological control strain of T. virens (Tv) in protoplast fusions with strains of T. harzianum (Th) and T. koningii (Tk). All fusants were morphologically similar to one of the parent species. When compared to the morphologically similar parent, two Tv-like fusants grew better at 10 degrees C than did the Tv parent, two Tk-like fusants showed significantly better biological control activity against Rhizoctonia on cotton than did the Tk parent, and one Tv-like fusant gave significantly less control than did the Tv parent. Fusants that were morphologically similar to Tv also differed in the production of secondary metabolites such as gliotoxin, viridiol, and heptelidic acid.