Jujube (Ziziphus mauritiana Lam.) is a culturally, ecologically, and economically significant species in arid and semi-arid regions worldwide, including Sumbawa Island, Indonesia. Its wide morphological and pomological variability necessitates assessment of the genetic diversity for utilization and future conservation. The 13 jujube accessions (10 wild and three partially domesticated from West Sumbawa [SB], Sumbawa Regency [KS], and Dompu [DP]) underwent analysis for genetic diversity using 27 SSR markers. Genetic diversity revealed variations in allelic richness and polymorphism levels, and the DP population had the highest allelic richness, followed by SB and KS. The principal component analysis (PCA) showed that KS accessions formed a genetically cohesive group, while DP accessions displayed more dispersion, with considerable intra-population variation and partial overlap with SB accessions. The SSR-based clustering divided the accessions into two major groups: cluster I (KS3L1, DP1L2, DP1L3, KS1L1, KS2L2, SB1L2, and SB2L1) and cluster II (SB2L2, DP2L1, SB1LI, DP2L2, DP3L1, and SB2L3), consistent with PCA results. The results confirmed distinct genotypic profiles among ecotypes and the effectiveness of SSR markers in capturing the population structure of Z. mauritiana across Sumbawa Island. The two distinct genotype groups reflect complex local adaptation and domestication processes, and SB accessions showed intermediate genetic signals likely influenced by ecological overlap and historical exchange of planting materials.
Jujube (Z. mauritiana), genetic diversity, SSR polymorphism, UPGMA clustering, principal component analysis (PCA), ecotype, domestication
The SSR markers considerably revealed genetic diversity and structure among the jujube (Z. mauritiana) accessions from Sumbawa Island, identifying two distinct genotypic clusters. It indicates the presence of at least two distinct genotypes, reflecting complex patterns of domestication and local adaptation within the island’s populations.