感染大麦黄花叶病毒(BaYMV)的大麦细胞质内含体及细胞器病变的研究

Cytoplasmic Inclusions and Organelle Alternations in Barley Infected by Barley Yellow Mosaic Virus (BaYMV)

超薄切片电镜观察表明,在感染大麦黄花叶病毒(BaYMV)的大麦(品种“早熟3号”)叶肉细胞中,液泡周围偶而可看到病毒颗粒束,在发病后期黄化或坏死的叶肉细胞中,可见到散布的病毒颗粒。在所有表现症状的病叶叶肉细胞,表皮细胞和木质部薄壁细胞中均可观察到风轮体、束状体、板状集结体以及膜状体等细胞质内含体,未见 卷简体和细胞核内含体。感病初期细胞中,细胞质丰富,核糖体数量增加,内质网肥大,随着病毒症状发喂,叶绿体、线粒体等细胞器逐渐肿大,外膜破裂直至解体。

Wheat yellow mosaic virus(WYMV) has been occurred on wheat in Shanxi province since 1970s. The virus preparation was purified from naturally infected wheat plants by extracting in 0.5mol/L potassium phosphate buffer pH7.0, clarifying in 1/4 v carbon tetrachloride, precipitating with 6% PEG, 3% NaCl and 1% Triton X-100 followed by two cycles of differential centrifugations with 20% sucrose cushions containing 0.3% Triton X-100 and finally centrifuged in 10-50% sucrose density gradients. The yields of virus preparation were about 7.45 mg/kg leaves. Purified virus preparation showed a typical UV spe- ctrum of a nucleoprotetin with max. and min. absorption at 260nm and 242nm, respectively, the ratios of OD_(260)/OD_(242) and OD_(260)/OD_(280) were 1.24 and 1.38. Purified virus preparations contained filamentous particles measuring 13-14nm in width, 250-300nm, 550-700nm in length, and contained a single polypeptide species of mol. wt of c. 30 kd. The virus particles were serologically trapped and decorated by Japanese antiserum against WYMV in immunosorbent electronmicroscopy(ISEM) tests. Numerous cylindrical inclusions(pinwheel) and complex membranous bodies in the cytoplasm of fresh infected wheat leaves were observed with an electron microscope.