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Genetic diversity analysis of crop genetic resources is a prerequisite for parental selection with suitable and complementary profiles for breeding. The objectives of this study were to determine genetic diversity present among okra accessions using simple sequence repeat (SSR) and complementary phenotypic markers and to select genetically divergent and superior parental accessions for pre-breeding. Twenty-six preliminarily selected okra accessions were assessed using nine highly polymorphic SSR markers and phenotyped under drought-stressed (DS) and non-stressed (NS) environmental conditions using a 13 × 2 alpha lattice design with two replications. Data were collected on the following eleven phenotypic traits: plant height (PH), days to 50% maturity (DTM), fresh pod length (FPL), dry pod weight (DPW), dry pod length (DPL), number of pods per plant (NPPP), pod yield per plant (PYPP), total above-ground biomass (AGB), harvest index (HI), root weight (RW), and root to shoot ratio (RSR). The SSR markers revealed an expected mean heterozygosity value of 0.54, indicating moderate genetic diversity among the tested okra accessions. Cluster analysis based on phenotypic and SSR markers differentiated the accessions into three distinct genetic groups. Wide phenotypic variation was observed for PH, FPL, NPPP, and PYPP under NS and DS conditions. PYPP was positively and significantly correlated with FPL (r = 0.81), ABG (r = 0.69), and HI (r = 0.67) under DS conditions, and FPL (r = 0.83) and AGB (r = 0.60) under NS conditions. Genetically complementary accessions such as LS04, LS05, LS06, LS07, LS08, LS10, LS11, LS15, LS18, LS23, LS24, and LS26 were identified for their high yield potential and related yield-improving traits under DS conditions. The identified accessions are recommended as parents for hybridization and selection programs to improve the yield potential of okra under drought-stressed environments. [ABSTRACT FROM AUTHOR]

Bambara groundnut is a highly nutritious underutilized legume crop, which can be cultivated in unfavorable environments, has the potential to address food security and can significantly contribute to climate-smart agriculture. The objectives of this study were to determine the phenotypic diversity and characterize a southern African bambara groundnut germplasm collection for grain yield and yield components, to identify superior bambara accessions and to determine the correlation between measured traits. The 100 bambara accessions were planted in two different locations over two seasons. There was significant variability among the accessions, locations, seasons and their interactions for all traits. Low broad-sense heritability values (<0.5) were observed for almost all traits. Significant positive correlations between all measured traits were observed. High-yielding accessions; WS 42 (AS), MV 67-1, K 5, AS 9, SCORE 1 and SB 12-3 were identified. Bambara accessions 224 (RF-7684), 179 (AB 16-5C), 121 (Red Ex Zimbabwe), 62 (SB 8-3), 9 (SB 4-1), 181 (SB 8-1B), 89 (AS 20), 217 (RF-6221), 94 (K 5), 177 (S1 Sel2) and 74 (AS 5) were associated with a high grain yield, plant spread and plant height. These accessions could be used as potential parents in a breeding program for the development of high-yielding varieties. [ABSTRACT FROM AUTHOR]