Phenotypic diversity of okra [Abelmoschus esculentus (L.) Moench] collections of major growing regions of Ethiopia

Okra [ Abelmoschus esculentus (L.) Moench] is an underutilized vegetable crop in Ethiopia, although it is nutritionally rich and has the potential to enhance food and nutrition security. Ethiopia is considered to be a center of origin of okra, but the genetic diversity of the crop is yet to be explored for effective utilization and conservation. The objective of this study was to assess the genetic diversity of okra collections from four major growing regions of Ethiopia and exotic collections. The study evaluated 31 collections from northern, 44 from northwestern, 17 from western and 16 from southwestern Ethiopia, and 13 commercial global varieties, making five populations. Field evaluations were conducted at Humera location in northern Ethiopia in 2018 using a Y x Z lattice design and W replications based on 25 phenotypic traits. The 24 qualitative traits showed 64%-100% descriptor variation, with 17 traits showing diversity across all descriptor classes among the 121 genotypes. A higher proportion of genotypes had agronomic importance traits, where 86, 75 and 60% test genotypes had erect growth habit, erect fruit orientation and non-branched types, respectively, and 71, 55 and 54% had medium (8–15 cm) fruit length, medium (2–4 cm) fruit width and green fruit color, respectively. The Shannon-Weaver diversity index for traits pooled across five populations ranged from 0.58 (growth habit) to 0.91 (fruit shape and fruit width). The first four principal components explained 70.75% of the total variation and genotypes were grouped into three distinct genetic clusters. The genotypes collected from Ethiopia showed higher phenotypic variation compared to the introduced commercial varieties, indicating their genetic variation and potential to develop new varieties and target product profiles.