Mercury-resistantPyrenophora aveniiein New Zealand seed oats: A comparison of six different compounds as seed disinfectants

摘要

Seeds from a sample of New Zealand seed oats heavily infected withPyrenophora avenaeIto and Kuribay. and carrying mercury-resistant strains of the fungus were treated with four different non-mercurial compounds (benquinox, fentin acetate with maneb, captafol, and thiram) as well as two organomercurial compounds in an attempt to evaluate their effectivness in controlling leaf spot and seedling blight. Benquinox completely suppressed growth of the fungus on agar, but it failed to give complete control of the disease in pot tests, and it adversely affected germination and growth of seedlings. The other three non-mercurial compounds gave little control. Incidence of mercury-resistant strains of the fungus in New Zealand seed oats is low, and the organomercurials seem likely to be the best seed dressings available for some time.