Abstract: | Volvariella volvacea, the straw mushroom, has long been considered as a primary homothallic species. However, great variations in monosporous isolates have ralsed a considerable debate on the sexuality pattern of this edible Basidiomycete fungus. Because clamp connection is absent in V. volvacea, the production of genetically marked strains offers a possible means of resolving this problem. In this study, ultraviolet irradiation of basidiospores and mycellal fragments was used to induce crystal-violet- and malachite-green-resistant mutants. Cross-resistance to crystal violet and malachite green occurred between both classes of mutant. The difficulties of inducing mutants in this multinucleate fungus and the significance of mutant markers are discussed.The authors are with the Department of Biology, The Chinese University of Hong Kong, Shatin, New Territories, Hong Kong. |