Diversity and Genetic Structure of Garlic(Allium sativum L.) Germplasm Resource in China

【Objective】The objective of the experiment is to understand the diversity and genetic structure of garlic germplasm resources in China.【Method】Two-hundred and twelve accessions of garlic germplasm preserved in China were detected and analyzed based on AFLP,SSR and InDel.Neighbor-joined clustering was analyzed by software Mega,and the population genetic structure was studied by software Structure 2.1.The effect of genetic structure on association analysis between the molecular markers and 21 quantitative traits including allicin content was evaluated by general linear model(GLM) by software SSPS13.0.【Result】Totally,502 allels were amplified by AFLP,SSR and InDel primers,and 492 of them were polymorphic among 212 accessions of garlic.All accessions were divided into 5 groups by both structure analysis and neighbor-joining clustering.However,the Shannon's index of each group assumed by genetic structure analysis was smaller than that assumed by neighbor-joining clustering,which indicated that the genetic structure analysis could interpret genetic relationship among the individual accessions in more details.Most of traits including allicin content were slightly affected by population structure,which indicated that the germplasm in this study was acceptable to be the populations for association mapping.【Conclusion】The garlic germplasm resources in China possess a great diversity.The population structure of the garlic germplasm resources slightly affect the quantitative traits including the allicin content,which means that the population of the garlic germplasm is a potential candidate natural population for association analysis between the molecular markers and the quantitative traits.