Phenotypic screening of cultivated and wild okra germplasm against yellow vein mosaic and enation leaf curl diseases of okra in India

Okra yellow vein mosaic (OYVMD) and enation leaf curl diseases (OELCuD) caused by whitefly (Bemisia tabaci) transmitted begomoviruses are important constraint for improvement and production okra in India. Okra germplasms consists of 178 cultivated/advanced lines (147 Advances okra lines + 31 popular varieties) and 146 accessions from 14 wild species originally collected from different national institutes located at different agroclimatic zones of India were evaluated for their response against OYVMD and OELCuD. The resistance levels both cultivated and wild species were assessed by visual scoring of symptoms in the field under natural conditions for two consecutive years in 2015 and 2016. None of the cultivated genotypes and wild species tested was found to be disease free except Abelmoschus enbeepeegeearnse, however, considerable variation in responses against OYVMD and OELCuD was observed among the genotypes. Of the 178 cultivated/advanced lines screened against OYVMD and OELCuD, seven genotypes showed highly resistant, one resistant, 2 moderately resistant and 146 accessions from 14 wild species, 17 accessions were showed highly resistant reaction, one accession resistant, 5 accessions moderately resistant for OYVMD. Similarly, for OELCuD, fifty-two okra genotypes showed highly resistant, three moderately resistant in cultivated/advanced lines and 125 accessions were found to be highly resistant, two resistant and three moderately resistant in wild accessions. The resistance cultivated/advanced lines could be used directly as varieties to manage OYVMD and OELCuD after adaption to various agroclimatic regions. The resistance in wild accessions could be used in future breeding programmes to develop okra cultivars resistant against both OYVMD and OELCuD.