Genetic Assessment Of Different Varieties Of Mentha

Mentha is perennial or rarely annual aromatic herbage which mostly has high commercial value. They are widely used in the area of food, cosmetic and medicine industry. However, the cultivation area and yield in China shrank day by day because of one of most important problem that varieties degradation, slow new varieties update and the decline of content and quality of essential oil. The creation research of menthe resource appeared as a very significant and urgent job. The hereditary background and relationship between the varieties and species existed domestic and abroad should be analyzed in order to cultivate the new variety.As to the 11 varieties of mentha collected,this experiment researched and deduced the hereditary relationship between the varieties by synthetically utilizing morphology, essential oil composition analyze and molecular marker technique in their separate advantage. This research hoped that it can provide new thinking and establish the foundation of creation of menthe resource.The content of this research included: Observation and description of botany properties of each growth period of the materials, screening and marking botany properties of obvious difference and carry on taxology research from morphological view; Extraction of the essential oil , determination and analyzing the composition of the oils, screening the representative chemical composition and mark in different levels, appraisal and analyzing the hereditary relationship and background from phytochemical view; Genetic relationships between eleven varieties of Mentha were analyzed by ISSR molecular marker technology. Genetic diversity and similarity were analyzed in molecular level. This research synthesizes the three different methods and result and deduces the hybridization origin and genetic relationship based on the representative varieties.The research result showed that the three cluster's analysis charts computed by the three analysis methods have certain coincidence. However, there are also some varieties were classified into the different classifications. Based on the representative varieties of Mentha pulegium L., Mentha piperita L., Mentha spicata L. and Mentha suaveolens, hereditary relationship analyze chart was drawn out. This result is believed could provide evidence to the further creation of menthe resource. The determination of hereditary relationship between Mentha species is always a difficult problem since the characteristic of easy hybridization and many chemical types of menthe. Morphology classification, essential oil composition analyze or molecular marker technique were used separately in evaluation and identification different species in past. But in the same time also find these methods all have uncertainty each. This research combined manifold methods to deduce hereditary relationship and background of varieties synthetically, the defects of each method are believed could be made up and the analysis result would be more close to the fact.