Association of a monopartite chilli leaf curl virus and defective betasatellite molecule isolated from leaf curl disease affected papaya in India

Papaya leaf curl disease (PaLCuD) is a serious problem to the production of papaya (Carica papaya L.) in India and infection due to this virus is not limited to papaya, but to chilli and tomato. In this study, leaf samples from diseased papaya plant showing extreme leaf curling and venation were collected from New Delhi region, India during the period of 2016–2017. Rolling Circle Amplification(RCA)–PCR-sequencing showed the presence of typical Old World begomovirus. The nucleotide sequence of two cloned begomovirus genome of this study shared maximum percentage nucleotide identity with chilli leaf curl virus (ChiLCV) and tomato leaf curl virus reported from different parts of India. Interestingly, a defective betasatellite DNA of 0.6 kb was found to be associated with one of the isolates of begomovirus under study. Agroinfectious clone of one isolate was developed and tested with the help of needleless syringe in chilli leaves which later developed into leaf curl disease symptoms. This is a first study in which biological and molecular characterisation of a recombinant ChiLCV isolated from papaya plant is demonstrated.