Genetic conversion of a fungal plant pathogen to a non-pathogenic, endophytic mutualist

Stanley Freeman; Rusty J. Rodriguez

doi:10.1126/science.260.5104.75

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Genetic conversion of a fungal plant pathogen to a non-pathogenic, endophytic mutualist

Stanley Freeman·Rusty J. Rodriguez

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Abstract

The filamentous fungal ascomycete Colletotrichum magna causes anthracnose in cucurbit plants. Isolation of a nonpathogenic mutant of this species (path-1) resulted in maintained wild-type levels of in vitro sporulation, spore adhesion, appressorial formation, and infection. Path-1 grew throughout host tissues as an endophyte and retained the wild-type host range, which indicates that the genetics involved in pathogenicity and host specificity are distinct. Prior infection with path-1 protected plants from disease caused by Colletotrichum and Fusarium .Genetic analysis of a cross between path-1 and wild-type strains indicated mutation of a single locus.

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Stanley Freeman, Rusty J. Rodriguez. 1993. Genetic conversion of a fungal plant pathogen to a non-pathogenic, endophytic mutualist. https://doi.org/10.1126/science.260.5104.75

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