Selecting donor parents for future breeding aiming at tolerance to viral diseases with special emphasis on enation leaf curl virus in Okra

ABSTRACT

Okra [Abelmoschus esculentus (L.) Moench] production is threatened by yellow vein mosaic virus (YVMV) and enation leaf curl virus (ELCV) diseases, of which ELCV has become prevalent and serious in the tropics. Identification of tolerance to ELCV among cultivated species of okra for utilization in breeding is lacking. The study was conducted to identify okra genotypes that can be utilized in hybridization to retrieve potential line(s) having degrees of tolerance against ELCV and YVMV, and which also exhibit high yield. Thirty-five okra genotypes, collected from different sources, were screened for tolerance to YVMV and ELCV and other quantitative traits. A wide range of variability occurred for the traits. No coincidence of YVMV and ELCV diseases occurred at the same time in any genotype. Genotypes were grouped into six distinct clusters emphasizing the relative contribution of various quantitative characters to total variability. The clusters do not represent place of origin indicating genotypes in a cluster were geographically diverse; genotypes obtained from the same region were genetically different. The principal components, Percent disease index (PDI) of YVMV, PDI of ELCV and plant height, had eigen values >1 and together accounted for 100% of total variation. Based on multivariate analysis and average values, genotypes ‘285-1-3A-1-17-1,’ ‘VRO-178,’ ‘285-1-3-1-15-2-1,’ and ‘12/OKYV RES-1’ were identified as potential donors that could be passed on to breeders for ELCV and YVMV disease resistant breeding, respectively.

KEYWORDS:

• Abelmoschus esculentus
• ELCV
• genetic diversity
• Okra
• selection indices
• YVMV

Acknowledgments

The authors acknowledge financial help, and cooperation, by the Project Coordinator, All India Coordinated Research Project on Vegetable Crops, Indian Council of Agricultural Research-Indian Institute of Vegetable Research, Varanasi, India to conduct the study.

Additional information

Funding

This study was financially supported by Indian Council of Agricultural Research – Indian Institute of Vegetable Research, Varanasi, India, through “All India Coordinated Research Project on Vegetable Crops”.