The largest group of plant viruses is Begomovirus genus. It encompasses round about 100 species. Begomovirus is main genus of family Geminiviridae. Begomoviruses can produce severe infections in several economically important crops all around the world. These are single stranded DNA viruses which are transmitted by Whitefly (Bemisiatabaci). These viruses can cause infection in dicots only. Begomoviruses are divided into two groups. Old world Begomoviruses are existing usually in Asia, America and Europe comprising of monopartite and bipartite genomes and new world Begomoviruses are mostly distributed in the American continent having bipartite genome. There are several DNA satellites which are also associated with Begomoviruses. This review mainly focuses on the classification of the Begomoviruses, origin and evolution of the Begomovirus associated satellites and Begomoviruses proteins functions. This review also sheds light on mode of infection, replication mechanism and Begomovirus-host plant interactions.

Several dicot plant species are mostly infected by the vast variety of begomoviruses in different areas around the globe. Begomoviruses exhibit association with two satellites molecules, alphasatellites and betasatellites which are involved to cause severe viral infection. Whitefly plays a vital role as a vector in the transmission of virus from one plant to another. These viruses use weeds to cause infections when the major crop plants are absent in the field. Ageratum conyzoides is very important weed plant, infected with a unique virus complex. The study is intended to evaluate the satellite molecule diversity associated with yellow vein disease of A.conyzoides. Symptomatic leave samples of field grown ageratum plants were collected from different areas of Faisalabad. Betasatellites were extracted from infected ageratum plants.To amplify the beta satellite component clones, the rolling circular amplification was applied on extracted DNA-β isolated from infectious weed plants.The confirmation of DNA-β was done with the help of restriction by different suitable enzymes. The betasatellites were mainly focused in this study. The DNA-β was completely sequenced and infectious molecule was made.