作者：曾惠中

類別：圖書文獻類 - 手稿

材質：紙質

年代：1969~1969

尺寸：長:24.6 x 寬:20.5 (cm)

藏品來源：曾惠中捐贈

登錄號：2019-001-0001-084

藏品描述：葉稻熱病：發病初期先於葉面上形成褐色或暗綠色小斑點，如環境適合，擴大成紡錘形。此時病斑周圍呈黃色，中間赤褐色，內部灰白色。嚴重時葉片枯萎甚至全株枯死。穗稻熱病：發生於穗頸、枝梗及穀粒。一般穗頸及枝梗上病斑呈淡褐色或暗褐色，穀粒之病斑則為暗灰色或白色。發病後穀粒不充實或為不稔粒。節稻熱病：稻莖節呈暗褐色，容易折斷，且上部逐漸枯死，通常在水稻抽穗後較易發現。葉舌稻熱病：發生在葉鞘與葉鄰接位置呈褐色。

Rice blast disease, caused by Magnaporthe oryzae, occurs in about 80 countries. It is one of the most devastating cereal diseases, resulting in losses of 10–30% of the global yield of rice. In rice seedlings, small necrotic regions appear initially, which become larger and coalesce, and have chlorotic margins. In older rice plants, disease symptoms can occur in leaves, collar–junction of the leaf blade and leaf sheath, nodes, neck, and panicle. Neck rot and panicle blast are particularly devastating causing up to 80% yield losses in severe epidemics. Triangular, purple-colored lesions form on the neck node which elongate on both sides, seriously impairing grain development. The panicles become white when young neck nodes are invaded; infection later in plant growth results in incomplete grain filling.