Classification of Southeast Asian mints (Mentha spp.) based on simple sequence repeat markers

Area of Science:

• Botany
• Genetics
• Plant Taxonomy

Background:

• The mint genus (Mentha) is complex due to hybridization and polyploidy.
• Southeast Asian mints are widely used but poorly distinguished.
• Accurate classification is crucial for understanding genetic diversity.

Purpose of the Study:

• To analyze Southeast Asian mints and known varieties using molecular and morphological methods.
• To develop and utilize simple sequence repeat (SSR) markers for mint classification.
• To clarify the genetic composition of unclassified mints.

Main Methods:

• Analysis of Southeast Asian mints, known varieties, and a related Lamiaceae species (Nepeta sp.).
• Utilized leaf morphology, including venation pattern and leaf shape index.
• Developed and applied 12 simple sequence repeat (SSR) markers for genetic analysis.

Main Results:

• Leaf morphology distinguished two types of mints.
• SSR markers provided good amplification in Mentha and Nepeta species.
• A phylogram based on SSR data delineated Mentha into groups I-VI.
• Southeast Asian mints were classified into groups I and II, aligning with known species M. × cordifolia and M. arvensis.
• Population structure analysis supported the observed groupings.

Conclusions:

• Simple sequence repeat (SSR) markers are effective for classifying mint species.
• This study enhances the understanding of genetic diversity within the Mentha genus.
• The developed SSR markers will aid in classifying and understanding Southeast Asian mints.