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：2019-001-0001-057

藏品描述：破壞性最大的咖啡樹疾病，為咖啡駝孢銹菌(Hemileia vastatrix)所致。此病症狀為葉表面出現黃色小油斑，後擴大成鮮橙色至紅色圓斑，最後轉褐色，具黃色邊緣。銹菌孢子堆位於葉下表面，橙黃色，後轉黑色。病葉下垂，逐漸脫落，數年內植株即死亡。控制方法為於潮濕季節及時噴殺真菌劑；某些地區的種植園已遷移至海拔1,800∼2,100公尺較涼爽的地方，在該處鏽菌不易繁殖。

Hemileia vastatrix is a fungus that causes coffee leaf rust, a devastating disease of coffee plantations. At first, the spots are small, and forming yellow-orange powdery blotches on the underside of leaves and yellow areas on top. Later, the center of the spots on the top turn brown with yellow margins. Blotches may merge and cover the leaf blade. In severely affected plants, leaves fall and branches die back. Infection causes leaf fall, and this in turn affects the growth of new stems, which bear the next season's crop. Berries may ripen prematurely, resulting in beans of poor quality. Overbearing dieback may eventually kill the trees. Overall, a 30 to 50% reduction in yield is possible from coffee rust.