Abstract
A new screening system to select anti-mildew substances using barley seedling was devised. To begin with, anti-mildew substances exhibiting translocating property were selected by means of brush inoculation method; a leaf of the seedling the root of which was wrapped in an absorbent cotton containing a test solution was inoculated with conidia of Erysiphe graminis from barley plant using a small brush. Preventive and, or curative activities was examined as the second screening; conidia of E. graminis were dispersed from inocula plants to the test plants by the artificial wind in a cabinet equipped with an electric fan. Finally, anti-mildew substance effective against the disease of cucumber was selected in a green house as the third screening. From among 1, 680 strains of Actinomycetes, only one strain (B-98891) was selected through the screening system. The brush inoculation method was successfully applied to detect anti-mildew activity through the isolation and the purification process of mildiomycin.
