First report of Cotton leaf curl Burewala virus infecting Ricinus communis.

Abstract

Castor bean (Ricinus communis; family Euphorbiaceae) is cul- tivated for the production of oil and as an ornamental plant throughout tropical regions. Leaf samples from castor bean plants with leaf curl and vein thickening were collected from ar- eas around Okara (Pakistan) in 2011. PCR amplification using di- agnostic primers showed the presence of a begomovirus and sub- sequently the specific primer pair (BurNF 5’-CCATGGTTGTG- GCAGTTGATTGACAGATAC-3’; BurNR 5’-CCATGGATT CACGCACAGGGGAACCC-3’) was used to amplify and clone the whole genome of the virus. The complete nucleotide se- quence was determined to be 2,759 nt (accession No. HE985227). Alignments showed the highest levels of nucleotide sequence identity (98.8%) with Cotton leaf curl Burewala virus (CLCuBuV; accession No. JF416947). The virus in castor beans lacks on intact C2 gene, as is typical of CLCuBuV in cotton (Am- rao et al., 2010). An amplification product of ca. 1.4 kb was ob- tained in PCR with primers for betasatellites (Briddon et al., 2002) and the complete nucleotide sequence of a clone was deter- mined to be 1373 nt (HE985228). The sequence showed 96.3% nucleotide sequence identity to the recombinant Cotton leaf curl Multan betasatellite (CLCuMB; JF502389). This is the first re- port of CLCuBuV and its betasatellite infecting castor bean, showing this plant species as an alternate host of the virus.