Genetic Diversity in Okra and the Effect of Some Physiological Treatments on Seed Yield

Abstract

Two experiments were conducted on okra. The first experiment aimed to study the genetic diversity among 25 genotypes of okra (Abelmoschus esculentus L.), coded sequentially from 1 to 25, using 11 ISSR primers. Results showed that the maximum genetic distance between genotypes 2 and 13 was 0.5. The genotypes (16 and 17), (16 and 18), (17 and 18), and (17 and 19) recorded the lowest genetic distance of 0.03. The dendrogram of the genetic relationship among the genotypes also divided them into two main groups, A and B. Group B included most Iraqi cultivars, including the local cultivar Al-Bateerah (genotype 5), which was selected for the second experiment. During the spring of 2025, the second experiment was implemented in a field at the College of Agricultural Engineering Sciences, University of Baghdad, Al-Jadriyah. The objective was to examine the impact of certain physiological treatments on enhancing seed yield and its components. The experiment utilized a 2 × 2 × 4 factorial arrangement in a randomized complete block design (RCBD) with three replicates. It studied the effect of spraying amino acids, coded A1, a fruit-set regulator containing auxins, coded G1, and nutrient elements [Ca-Mg, coded N1; P-K, coded N2; and micronutrients + S, coded N3] on okra seed yield and its components. The results showed significant effects of the three-way interactions, two-way interactions, and individual factors on all studied traits. The treatment A1G1N3 achieved the highest values in seed yield (192.23 g plant−1), 1000-seed weight (75 g), seed bulk density, seed true density, germination percentage, and germination speed. The treatment A1G1N1 produced the highest number of dry pods.