VIEW ARTICLE

Genetics and Nutritional Requirements of Endothia parasitica. John E. Puhalla, Department of Genetics, The Connecticut Agricultural Experiment Station, New Haven, Connecticut 06511; Sandra L. Anagnostakis, Department of Genetics, The Connecticut Agricultural Experiment Station, New Haven, Connecticut 06511. Phytopathology 61:169-173. Accepted for publication 8 September 1970. DOI: 10.1094/Phyto-61-169.

A medium containing inorganic salts, glucose, and thiamine supports good growth and conidial production of Endothia parasitica, but the conidia require the addition of biotin or aspartate for germination. The pH optimum for mycelial growth is 4, and the fungus does not grow above a pH of 5.5. The optimal temperature range is 25-30 C. Light does not affect mycelial growth rate or pigment development, but is necessary for formation of conidia. Biochemical and morphological mutants isolated after irradiation with ultraviolet light were used to synthesize heterokaryons and putative diploids. Perithecia containing normal ascospores were formed in the laboratory on chestnut stem segments inoculated with genetically marked strains. Ascospore analysis suggests that E. parasitica is homothallic but will preferentially outcross.