The complete genome of a Thailand isolate of the geminivirus tomato yellow leaf curl virus (TYLCV-Th) has been cloned and the nucleotide sequence determined. The genome consists of two DNAs each slightly greater than 2700 nucleotides in length and designated A-DNA and B-DNA. The A-DNA contains six open reading frames (ORFs) capable of encoding proteins with M(r)s greater than 10K; two ORFs were...

Geminiviruses encapsidate single-stranded DNA genomes that replicate in plant cell nuclei through double-stranded DNA intermediates that associate with cellular histone proteins to form minichromosomes. Like most plant viruses, geminiviruses are targeted by RNA silencing and encode suppressor proteins such as AL2 and L2 to counter this defense. These related proteins can suppress silencing by m...

Genomes of two isolates of tomato leaf curl geminivirus from India (ToLCV-India) have been sequenced. ToLCV-India contains A and B components, both of which are required for systemic movement and symptom development. The two isolates have 94% sequence identify but one isolate gave mild symptoms in Nicotiana benthamiana and tomato. The genome organization of ToLCV-India is similar to other white...

Abstract Geminiviruses can infect a wide range of plant hosts worldwide and have hence become an emerging global agroeconomic threat. The association these viruses with satellite molecules highly efficient insect vectors such as whiteflies further prime their devastating impacts. Plants elicit strong antiviral immune response to restrict the invasion destructive pathogens. Phytohormones help pl...

The genome of tomato leaf curl virus (TLCV) from Australia was cloned and its complete nucleotide sequence determined. It is a single circular ssDNA of 2766 nucleotides containing the consensus nonanucleotide sequence present in all geminiviruses. It has six open reading frames with an organization resembling that of certain other dicotyledonous plant-infecting monopartite geminiviruses, i.e. t...

Each year geminiviruses cause millions of dollars in damage to tomato crops in Central America. Attempts to create a resistant plant with a suitable fruit through breeding programs have been unsuccessful. This study hopes to develop a molecular marker for the gene that controls resistance to geminiviruses. We hypothesize that a molecular marker for geminivirus resistance can be found within the...