油菜病毒病种子带病毒的初步研究

 感染芜菁花叶型病毒和烟草花叶型病毒的油菜病株种子的种皮内带有病毒,种胚自未成熟到成熟始终不带病毒。
烟草花叶型病毒在种皮内的存活期限长于芜菁花叶型病毒。烟草花叶型毒株61-16号,在"胜利"油菜病株种子的种皮内可以存活26个月以上;芜菁花叶型病毒存活期最长的一个毒株不超过25个月,最短的不到4个月。

DETECTION OF VIRUSES IN SEED COAT OF RAPE

Three isolates of the turnip mosaic group (isolate No.61-15,62-12 and 62-14) and one isolate of the tobacco mosaic group (isolate No.61-16) from the rape were used to inoculate Brassica napella C.and B.campestris L.in the greenhouse,and seeds of the diseased plants were collected to test for the respective virus.The seeds were disinfected by dipping in 5% Na₃PO₄ for ten minutes,and the embryo and the testa of the seed was assayed for the presence of viruses by inoculating their expressed extracts on suitable test plants.Nicotiana tabacum L.var.Samsum was used to assay the virus of the turnip mosaic group,N.glutinosa L.was used to assay the virus of the tobacco mosaic group.Results proved that these viruses were found only in the testa of the seeds,and the embryo was virus-free at all stages of its development.The virus in the testa remained viable for a certain period of time,but the amount of viable virus decreased readily during storage.The virus of the tobacco mosaic group in the testa remained viable longer (over 26 months) than the virus of the turnip mosaic group (4-25 months).No evidence was found to indicate that the virus carried in the testa could induce seedling infection.