Molecular identification and biological characterisation of a begomovirus associated with okra enation leaf curl disease in India.

Venkataravanappa, V.; Reddy, C.N.; Jalali, Salil; Briddon, Rob; Reddy, M.

An unusual symptom was noted in okra originating from Haryana state (India) consisting of leaf curl associated with enations. These were distinct from the leaf curl and/or vein yellowing symptoms usually shown by okra. PCR-mediated amplification was used to show the presence of a begomovirus and the complete genome sequences were determined for seven isolates. The sequences showed high levels of nucleotide sequence identity (91.9-99.1 %). In comparison to begomovirus sequences available in the databases the okra sequences showed the highest levels of nucleotide sequence identity (84.5 to 87.1 %) with Mesta yellow vein mosaic virus (MeYVV) and thus were classified as belonging to a novel begomovirus species, tentatively named Okra enation leaf curl virus. In common with the majority of begomoviruses, Okra enation leaf curl virus (OELCuV) was shown to have a recombinant origin. Analysis of the transmission characteristics of a wild-type virus isolate by Bemisia tabaci showed the minimum acquisition access period to be 1 h and the minimum inoculation access period to be 30 min, with female insects transmitting with a greater efficiency than male insects. Under controlled conditions the host range of the virus was shown to be very narrow, limited to two species in the family Malvaceae, okra ( Abelmoschus esculentus) and hollyhock ( Althaea rosea), and seven in the family Solanaceae.

INDIA; BEGOMOVIRUSES; OKRA; LEAF diseases & pests; SWEETPOTATO whitefly; PLANTS; POLYMERASE chain reaction; HOLLYHOCK

European Journal of Plant Pathology, 2015, Vol 141, Issue 2, p217

0929-1873

Academic Journal

10.1007/s10658-014-0463-0