Genetic Diversity and Differentiation Among Guatemalan Cardamom (Elettaria cardamomum (L.) Maton) Accessions

TL;DR

This study explores the genetic diversity of cardamom in Guatemala, revealing low diversity likely due to historical challenges and offering insights for future breeding.

Contribution

The study provides the first genetic baseline for Guatemalan cardamom using molecular markers and identifies potential for marker-assisted selection.

Findings

Low genetic diversity was observed in Guatemalan cardamom accessions, consistent with historical bottlenecks and human-driven selection.

Three distinct genetic groups were identified using Bayesian and hierarchical analysis.

Private and high-frequency genetic bands suggest potential for marker-assisted selection to improve resilience and productivity.

Abstract

Cardamom (Elettaria cardamomum (L.) Maton) is a major export crop in Guatemala; however, its genetic basis remains largely unexplored. This study aimed to evaluate the genetic diversity and differentiation among 288 cardamom accessions from the Northern Transversal Strip, the country’s primary production area. Eleven molecular markers (SSR, ISSR, and EST-SSR) were used to generate multilocus profiles analyzed under a dominant model. Genetic diversity revealed average values of Shannon’s index (I = 0.316) and expected diversity (h = 0.207), with SSR markers providing the highest values (I = 0.364, h = 0.233). Bayesian and hierarchical analysis identified three genetic groups (K = 3). The relatively low diversity observed is consistent with the introduction history of this crop in Guatemala, human-driven selection, and historical bottlenecks caused by Cardamom Mosaic Virus and thrips infestations. Despite these constraints, private and high-frequency bands were detected across genetic groups, offering potential for marker-assisted selection. These findings provide the first genetic baseline for Guatemalan cardamom, supporting future breeding strategies aimed at improving resilience, productivity, and adaptation to climate change.

Figures