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以云南烟草丛枝症病株为毒源，通过蚜虫传染接种大十字期、猫耳朵期、摆盘期、团棵期、旺长期和现蕾期的烟株，观察症状反应并检测与云南烟草丛枝症病害相关的低分子量ＲＮＡ．研究表明：云南烟草丛枝症病害的病程可分为４个阶段：潜育期、过敏反应期、缩顶期和丛枝期，烟株从感染到表现丛枝要经过约１个月；蚜虫接种后约１周，在蚜虫口针刺吸部位开始出现褪绿斑，继而产生强烈的过敏反应，即从褪绿斑中心开始坏死出现蚀点斑，叶片上布满坏死斑纹，有典型的环纹和蚀纹，严重的烟株叶片破裂，细脉坏死；随后进入缩顶期，烟株生长缓慢，叶间距明显缩短，顶部几乎成为一个平面，叶色稍黄，大十字期和猫耳朵期接种烟株缩顶后生长极其缓慢，萎缩成为僵苗，不表现丛枝症状，也不会开花结实；感染约４周后，摆盘期、团棵期、旺长期和现蕾期接种的烟株开始腋芽丛生，生长速度加快，几天后便表现为典型的黄化丛枝症状，叶黄化且变圆，能够开花结实．其症状和文献记载的所有烟草丛枝、丛顶和丛蔟类病害有明显区别，初步认为是１种未见记载的新病害，建议称之为“烟草簇矮病（Ｔｏｂａｃｏｂｕｓｈｙｄｗａｒｆ）”．文中附病程症状图２版．
Tobacco witches twig disease in Yunnan Province was used as a source of infection. Aphids were used to inoculate tobacco plants with large cross, cat ears, wobble, Bush disease disease associated low molecular weight RNA. The results showed that the disease course of Yunnan bush could be divided into four stages: latent period, anaphylactic reaction period, shrinkage period and bush branch. About 1 week after inoculation, chlorotic spots began to appear in the acupuncture points of the aphids, and then there was a strong anaphylactic reaction, that is, the necrotic spots appeared from the center of the chlorotic spot and the necrotic spots were covered on the leaves. Typical rings Wrinkles and necrosis. The leaves of the serious tobacco plants ruptured and necrosis of the veins died. Afterwards, the tobacco plants grew slowly and the leaf spacing was shortened. The top became almost a flat surface. The leaf color slightly yellow, large cross and cat ears Inoculation of tobacco plant shrinking after the top growth is extremely slow, shrinking into a stiff seedlings, does not show the symptoms of Congzhi, it will not flowering; infection about 4 weeks after the wobble, the Mission period, prosperous period and budding period of tobacco Strain axillary buds began to grow, the growth rate to speed up, a few days later showed a typical symptoms of yellowing Cong, yellowing and round, able to flowering. The symptoms and records of all the tobacco bush, plexus and Cong Cong disease are significantly different, initially considered to be an undiscovered new diseases, it is recommended that the “Tobacco cluster dwarf disease (Tobacobushydwarf).” Attached to the article pathological symptoms Figure 2 version.