In order to study the suitable transplanting date in Xingshan county Nicotiana tabacum L.producing areas,the experiment of four transplanting dates was conducted using randomized block design.The results showed that when the transplanting time of N.tabacum seedlings was during May 5 to May 20 in Xingshan county,the tobacco mosaic disease(Tobacco mosaic virus) and brown spot disease[Alternaria alternata(Fries) Keissler] were under control,the upper leaves of the plant were better,the yield and value was rela...