Screening of genotypes against viral diseases and assessment of yield loss due to yellow vein mosaic virus in okra grown in the eastern part of India

Yellow vein mosaic virus (YVMV) and enation leaf curl virus (ELCV) are major viral diseases of okra (Abelmoschus esculentus [L.] Moench) in the tropics threatening its commercial cultivation. The study aims to screen okra genotypes against viral diseases and to study inter-relationships between YVMV disease severity and whitefly population with leaf morphological parameters and to assess the extent of marketable yield loss due to YVMV infection. Out of 565 genotypes screened, only BCO-1 was found to be resistant against YVMV disease, while two genotypes IC111551 and IC433616 were found moderately susceptible against ELCV disease up to 60 days after sowing. Negatively significant correlations were recorded between adaxial and abaxial pubescence density and the number of whitefly adults throughout the growth stages of plant. Similar trend of correlations were also observed between leaf morphological parameters and YVMV disease severity. The marketable yield loss of YVMV ranged from 17.09 to 96.49%. The resistance of BCO-1 to YVMV and ELCV is based on antixenotic property of the genotype, and could be utilized in future dual disease resistant breeding programme.