The viral nature of a disease of Ageratum conyzoides showing yellow vein-banding and leaf crinkling was established by transmission studies.The virus was graft transmissible from infected to healthy A. conyzoides. However, it was neither sap nor seed transmissible. Whiteflies, Bemisia tabaci, were found to be the vectors of this virus.They readily acquired and transmitted the virus from diseased to healthy A. conyzoides after a 24-hour acquisition access period. In a host range study using viruliferous whiteflies, only A. conyzoides was found to be susceptible to the virus. The name, Ageratum yellow vein-banding has been proposed for the virus. 

Full Text ( 292 KB )