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日本1967年报导了一种新的由土壤传染的认为是由病毒引起的“水稻坏死花叶病”。病株分蘖减少、矮化,叶片自下而上有花叶斑驳出现,这种花叶斑驳多自叶身尖端中部开始,起初是宽约1毫米、长约1～2厘米的长纺锤形退绿斑,以后退色斑增多,扩展成长约10厘米边缘玻状的淡绿色到黄色的条斑,后期病叶变黄,抽穗期以后则在剑叶表现症状;同时在茎秆基部和叶鞘基部出现纵长褐色坏死斑,可扩展到全株,在剑叶叶鞘上部第一节附近也可看到,病株即
Japan reported in 1967 a new soil-borne “rice necrotic mosaic disease” caused by a virus. The diseased plants have fewer tillers and dwarfities, and mosaic leaves appear mottled from bottom to top. This mottled mottled leaf begins at the tip of the tip of the blade with a long spindle-shaped recess of 1 mm in width and 1 to 2 cm in length Green spot, after the discoloration increased, expanded to grow about 10 cm edge glassy pale green to yellow streaks, the late diseased leaves turn yellow after heading stage in the performance of the flag leaves; the same time in the base of the stem and leaf sheath base Long brown necrotic spots appear, can be extended to the whole plant, in the upper part of the upper leaf blade sheath can also be seen near the first,