Genetic diversity among Brazilian okra landraces detected by morphoagronomic and molecular descriptors

Abstract

The conservation of okra landraces [Abelmoschus esculentus (L.) Moench] in gene banks is essential for the success of their use in breeding programmes. This study evaluated the genetic diversity among okra landraces in Brazil based on morphoagronomic descriptors and AFLP markers. We studied 30 accessions of the vegetable gene bank of the Universidade Federal de Viçosa. To this end, 17 morphoagronomic descriptors and five combinations of AFLP primers were used. Genetic parameters were estimated for the quantitative traits and the accessions were grouped by Ward’s method, using the Gower’s and Jaccard’s distance measures, respectively, for the morphoagronomic and molecular data. Polymorphisms were observed for all qualitative traits, while the quantitative traits were significant by deviance analysis. The genetic parameters confirmed the existence of variability among accessions, and high accuracy and heritability indices were found for the traits related to fruit and plant height. Ward’s grouping showed no relationship between the clusters formed with the morphoagronomic and molecular data and the geographical origin of the accessions. No association between morphoagronomic descriptors and AFLP markers was observed. The lack of correlation suggests that both approaches of characterization are important to understand and differentiate the okra accessions.

Evaluation of okra landraces based on agronomic and biochemical traits

“…Accessions UEL2, UEL5, UEL10 and UEL15 that constitute the group 2 presented intermediate means for most of the evaluated traits (Figure 2). The wide genetic variability among these accessions was also observed by Massucato et al (2020) from the morpho-agronomical and molecular characterizations. Also, according to the authors, genetic dissimilarity of these accessions is related to different geographic locations of genotypes, as well as to the breeding carried out by small farmers.…”

“…The variability for agronomic and biochemical traits of okra has not yet been fully revealed, which is extremely important resource for plant breeding programs. Several studies have addressed the characterization of the genetic diversity of okra landraces based on phenotypic descriptors in different regions of the world ( Reddy et al, 2012;Yonas et al, 2014;Asare et al, 2016;Ramgiry & Singh, 2017) including Brazil (Massucato et al, 2020). However, to the best of our knowledge, there is little information about biochemical characteristics, which is also important for advancing the okra breeding.…”

“…Nine landraces of okra (UEL2, UEL3, UEL5, UEL6, UEL7, UEL9, UEL10, UEL13 and UEL15) were selected from germplasm bank of the Universidade Estadual de Londrina (UEL), which already were molecularly characterized (Massucato et al, 2020). The genotypes were evaluated in the experimental area of UEL in Londrina, Paraná, Brazil (23°19'42"S, 51°12'11"W), from January to April 2019 in field conditions.…”

Seed production system and adaptability of okra (Abelmoschus esculentus L.) cultivars in Buea, Cameroon

“…Massucato et al . [ 29 ] in a study conducted on 30 accessions of okra in Brazil, noted that small farmers usually store some of the seeds to sow during the next cropping season, generation after generation. The dominant cropping system for both seed production and okra cultivation was mixed cropping, followed by monoculture.…”

“…Ahiakpa et al [28] also presented similar findings and said that traditional farmers often engage in selection for different purposes, facilitating its diversification into a vast number of landraces adapted to various agroecological systems. Massucato et al [29] in a study conducted on 30 accessions of okra in Brazil, noted that small farmers usually store some of the seeds to sow during the next cropping season, generation after generation. The dominant cropping system for both seed production and okra cultivation was mixed cropping, followed by monoculture.…”