Diversity of Okra [Abelmoschus esculentus (L.) Moench] Genotypes in Ethiopia
Background: Ethiopia is considered as a center of origin of okra [Abelmoschus esculentus (L.) Moench], but limited information is available on the genetic diversity of the crop in the country.
Objectives: This research was conducted to assess the genetic diversity of okra genotypes in Ethiopia.
Materials and Methods: Twenty-nine okra genotypes collected from Ethiopia and three varieties of the crop obtained from other countries were evaluated for 24 morpho-agronomic traits for two seasons in Ethiopia in a randomized complete block design with three replications. Besides, 19 Simple Sequences Repeats (SSRs) primers were used to assess the genetic diversity of okra genotypes.
Results: The genotypes showed significant differences for 24 morpho-agronomic traits. The number of days required by the genotypes to reach the first fruit harvest ranged from 55 to 84 days; the average plant height of the genotypes ranged from 106 cm to 173 cm, tender fruit weight from 14.65 g to 31.43 g, fruit yield per hectare from 0.89 t ha–1 to 32.13 t ha–1, number of seeds per pod ranged from 59 to 124 and hundred seeds weight ranged from 5.3 to 7.16 g. Growing season, genotype, and year and genotype interacted to significantly influence most of the traits except internode length, leaf length, and width, number of fruits per plant and number of ridges and seeds per pod and hundred seeds weight. The four principal component axes accounted for 72.588% of the total variation with an Eigenvalue of 8.702 to 1.645. The Euclidian distances between pair of genotypes ranged from 2.36 to 12.36 as estimated from 24 morpho-agronomic traits and grouped the genotypes into nine clusters. The 18 SSRs polymorphic primers amplified 120 fragments with a size of 61 to 414 bp. Euclidean distances calculated from120 alleles ranged from 2.2 to 7.10 and grouped the genotypes into seven distinct clusters. The distances of genotypes as estimated from SSRs and morpho-agronomic traits showed significant and positive linear relationships.
Conclusion: The diversity of the crop was assessed efficiently both by SSRs markers and data from morpho-agronomic traits. This implies that the genetic diversity existing among the studied okra genotypes represented varied morpho-agronomic traits, which can be used for the development high yielding new varieties for enhancing production of the vegetable crops in the country.