REPORT ON EXPERIMENTS TO CONTROL CORN DOWNY MILDEW IN THAILAND

บทคัดย่อ

Downy mildew (DM) of corn (Zea mays L.) is regarded as a serious disease in several countries in Asia and in some other regions of the world. In Thailand, the disease first reached epidemic proportions in 1986. The disease has apparently occurred in Nakhon Sawan Province on corn for several years prior to the 1968 official report and perhaps in Lop Buri Province as well. It was first seen at Farm Suwan (Thailand’s center for corn and sorghum improvement) in Nakon Rachasima Proveince in October-November, 1970 and become epidemic there after early season rain in April-May. 1971. Currently it is found in nearly all corn producing areas. Unless it is brought under control this disease may soon be reducing yields by 40% as it India (5) the Philippines (3,8) and Taiwan (1).