1984年5月在云南省保山茶区发现茶树(Camellia sinensis)黄化病。感病茶园发病率约30％,甚至高达50％。主要为害梢部,新发出的芽叶显著变小(叶面积减小70％),均匀发黄。新梢节间缩短,簇生,表现出系统侵染的症状,尤以春茶时期发病为重。偶见叶片呈镰刀状畸形。雨后晴天,叶尖及尖部叶缘常变成黄褐色,进而变枯。发病严重时,芽叶稀少,芽蔫瘪不展,黄色幼叶易脱落,几乎无茶可采。成叶很少,成叶有时除主侧脉绿色或淡绿色外,其余部分为黄色或黄白色。植株矮小,枝条回枯,数年内终至整株死亡,对茶叶生产影响极大。由于该病特有的黄化、小叶、簇生等症状与茶树缺锌症状相似,故曾按生理病害作过试验研究,结果表明不是生理病害。1986—1987年,进行了电子显微观察。取症状明显的幼叶的主脉切成1～2mm~3大小,经常规方法戊二醛-锇酸双固定,丙酮系列脱水,环氧树酯包埋,超薄切片。醋酸铀-柠檬酸铅双染色。JEM-100CX透射电镜观察 May 1984 Camellia sinensis yellowing disease was found in the tea area of ​​Baoshan, Yunnan Province. Sick tea plantation incidence of about 30%, or even up to 50%. The main tip of the shoot, the newly issued shoots significantly smaller (leaf area reduced by 70%), uniform yellow. New shoots internode shortening, clustering, showing the symptoms of systemic infection, especially in the spring tea incidence. Occasionally leaves sickle-shaped deformity. Sunny day after the rain, leaf tips and sharp edges often become brown, and then become dry. When the disease is serious, sprouts sparse, Bud Shou deflated not show, yellow leaves easy to fall off, almost no tea recoverable. Leaves into a very small, sometimes into the leaves in addition to the main flank green or light green, the rest is yellow or yellowish white. Short plants, branches back to dry, died within a few years to the whole plant, a great impact on tea production. Due to the disease unique yellow, leaflet, tufted and other symptoms of zinc deficiency similar to tea, it had been made by physiological disease test study, the results show that not a physiological disease. From 1986 to 1987, electron microscopy was performed. Take the main symptoms of young leaves of the main cut into 1 ~ 2mm ~ 3 size, by conventional methods glutaraldehyde - osmium acid double fixation, acetone dehydration series, epoxy resin embedded, ultra-thin slices. Uranyl acetate - lead citrate double staining. TEM observation with JEM-100CX