以浙江省的水稻黑条矮缩病和河北省的玉米粗缩病的病毒分离物为材料．对我国南北方两种病毒分离物进 行了比较研究。两种病毒分离物的粒子大小形态相似，且在血清学上密切相关；二者的介体、寄主相同，并引起相 同的症状。提纯两种病毒分离物的基因组片段凝胶电泳显示它们相应的基因组片段之间大小极其相似： 根据水 稻黑条矮缩病毒(ttiee black streaked dwarf virus)，RBSDV的研和s8设计引物，利用RT-PC~技术，在两种病毒分离物 中均可特异扩增到预期太小的片段。序列测定比较分析表明：它们的同源性达97．0％ 一98 9％，与日本R．BS’DV的 同源性(92 2％ 95．5％)高于与意太利MRDV的同源性(76．6％ ～88 4％)。从而认为我国南方的水稻黑条矮缩病 和北方和玉米粗缩病都是同一种病毒——RBsDv引起的，也就是说我国北方的玉米粗缩病病原实际上是水稻黑条 矮缩病毒，而不是玉米粗缩病毒。

Two isolates of plant reoviruses causing severe stunting and dark leaf symptoms on wheat and maize from Hebei province and on rice from Zhejiang province have been characterized.The virus particles of both isolates were about 60～80nm in diameter and closely related serologically.Their dsRNA electrophoretic profiles in agarose gel were similar.They were both transmitted efficiently by the planthopper Laodelphax striatellus to maize and rice from their original hosts but maize was not a very suitable host for the vector and was a poor source of virus.Two fragments corresponding to dsRNA parts of rice black-streaked dwarf virus(RBSDV)S7 and S8 were amplified by RT-PCR from both isolates and sequenced.There were 97.0～98.9% identical nucleotides between the two Chinese isolates,which appear to be RBSDV(92.2%～95.5% identical nucleotides to Japanese isolate)rather than maize rough dwarf virus(79.6%～88.4% identical nucleotides to Italian isolate).