Unveiling Genetic Variation in Garlic Genotypes in Response to Rust Disease Using RAPD Markers

Abstract

Garlic (<em>Allium sativum</em>), cultivated worldwide for its medicinal and nutritional value, faces challenges due to diseases caused by various pathogens. In this study, eleven garlic genotypes from Iran and one from China were selected and sown under natural infection rendered by the rust fungus (<em>Puccinia alli</em>) over two consecutive years. Subsequently, disease distribution and severity, percentage of infection and susceptibility of different garlic genotypes to rust disease were investigated. The results showed that genotype Solan was the most susceptible, with disease severity of 30.81%. In comparison, genotypes Aliabad and Bahar were resistant against rust disease with the lowest infection percentages of 13% and 16.37%, respectively. Further, genetic diversity was assessed using random-amplified polymorphic DNA (RAPD) markers. Out of 10 primers used, 95 scorable bands were generated, of which 66 (69.48%) were found to be polymorphic. A dendrogram was constructed based on RAPD polymorphism using the UPGMA method, and the genotypes were separated into six distinct clusters based on Jaccard's coefficient of similarity. Additionally, it was observed that there is no genetic differentiation among the genotypes based on their geographical origin. This study highlights the significant diversity in resistance and susceptibility among garlic genotypes, which can be harnessed in plant breeding programs.