Assessment of genetic diversity and population structure analysis in Himalayan garlic genotypes from Sikkim using SSR markers.

BACKGROUND

Garlic (Allium sativum L.) is an important crop with significant medicinal and culinary uses. Understanding the genetic diversity and population structure of Himalayan garlic genotypes from Sikkim is crucial for effective breeding and conservation efforts. This study aims to analyze the genetic diversity among 60 Himalayan garlic genotypes collected from various altitudinal locations of Sikkim, India, using 27 Simple Sequence Repeats (SSR) markers.

METHODS AND RESULTS

The genetic diversity was assessed using SSR markers, which revealed substantial variation among the genotypes. The number of alleles (Na) ranged from 1.13 to 2.00, while the major allele frequency (MAF) varied from 0.672 to 0.963. The observed heterozygosity (H) ranged from 0.0667 to 0.475, indicating moderate genetic diversity. Population structure analysis using STRUCTURE software grouped the genotypes into three distinct sub-populations, suggesting genetic differentiation not solely based on leaf morphology. Analysis of Molecular Variance (AMOVA) showed that genetic variation was more significant among individuals within populations (41%) than among populations (16%). UPGMA dendrogram and Principal Coordinates Analysis (PCoA) further confirmed the genetic relationships among the genotypes.

CONCLUSIONS

This study reveals significant genetic diversity among Himalayan garlic genotypes from Sikkim, with clear genetic differentiation observed within and between populations. The results highlight the importance of both leaf morphology types and genetic structure in understanding the genetic basis of phenotypic variation in garlic. The finding provides valuable insights for future breeding programs and conservation strategies, emphasizing the need to consider morphological and genetic data for effective germplasm management and improvement of garlic cultivars.