2014 Volume 56 Pages 37-41
We examined the effect of lime applications with serial earthing-ups on welsh onion white rot disease in an infested field. By 4-serial lime applications from October until December, the rate of vendible welsh onions was raised from 3.3% to 24.0%. To define the effect of maintaining high soil pH in cold season, we carried out the inoculation test using a combination of leaf sheath disks and sclerotia at different pH values and temperatures. The disease incidence in leaf sheath disks with the initial pH 7.0 or 7.5 was significantly fewer than that with pH 6.5 or lower at 10 or 5°C. From these results, we suggest the benefit of the maintaining high soil pH in cold season to alleviate welsh onion white rot disease.