【摘要】 在西北农业大学校园内的白三叶草上分离到Wc分离物。该分离物经汁液摩擦接种莱豆和豇豆只产生局部坏死斑,在烟草上为系统侵染。致死温度为55℃,体外保毒期为12—24小时,稀释限点为10^-2—10^-3。琼脂双扩散试验表明Wc分离物与AMV抗血清有明显的沉淀反应。部分提纯制品在电镜下有5种形态:宽度一致（18—20nm）,长度分别为58、52、41和31nm,第5种粒子近球形。病毒粒子经3％凝胶电泳,染色扫描后有4个峰。超速离心分析有4个主峰,其沉降系数分别为S_20.w=98s（B组份）,82s（M组份）,72s（T_b组份）,和65s（T_a组份）。鉴定结果表明Wc是AMV的一个分离物。降解病毒所得总核酸（未变性）经聚丙烯酰胺凝胶电泳测定了4种核酸的分子量如下:RNA₁=1.3×10⁶,RNA₂=1.0×10⁶,RNA₃=0.8x10⁶,RNA₄=0.3×10⁶。更多还原

【Abstract】 A virus isolate-Wc has been obtained from diseased white clover which grows in the campus of Northwestern Agricultural University. The Wc isolate only gives necrotic local lesions on bean and cowpea without systematic spread, but systematic on tobacco. The thermal death point is between 50—55℃. The life in vitro is 12—24 hours and the dilution end point is 10^-2—10^-3.Under EM, partially purified virus preparation presents five components with uniform width（18—20nm） but different in length （58, 52, 41, 31 and 18—20nm respectively）.Four major peaks have been deteced on the 3％ PAGE after staining with Xylene Brilliant Cyanin C and scanning by visible light,Sehlieren and U/V pattern of We preparation in the analytical ultracentrifuge give four major peaks with S_20·w=98, 82, 72 and 65s. The whole results suggest that the four major components of We isolate are in correspondence with the four well known eomponents B, M, Tb, Ta of AMV. The viral n ucleie acids are extracted and purified, the biological activity of the viral nucleic acids are normal. The RNA’s molecular weights are also determined by PAGE. The four kinds of viral nucleic acids are RNA1=1.3×10⁶, RNA2=1.0×10⁶, RNA3=1.8×10⁶ and RNA4=0.3×10⁶ dalton. These calculated results may be higher than the actual situation.更多还原