PENNYROYAL (MENTHA PULEGIUM) AND HART´S PENNYROYAL (MENTHA CERVINA) BIODIVERSITY IN ALENTEJO, PORTUGAL

Mentha pulegium and M. cervina are traditionally used in Alentejo to flavour fish and “açordas” recipes, as well as for medicinal purposes. The essential oil has also industrial applications in foods conservation. M. pulegium is still common in nature, but M. cervina has been disappearing due to excessive collection, overgrazing and habitat destruction. This study was based on 25 accessions for M. pulegium and 30 accessions for M. cervina collected in backyards and the wild to represent the natural habitat of the Alentejo region. Data on morphological descriptors were submitted to principal component analysis (PCA) and cluster analysis. Accession clusters were found for both taxa. M. pulegium cluster group 1 was characterized by plants with the longest stem length, the largest plant diameter, and the tallest plants, while M. pulegium cluster group 2 contained the remaining acessions. M. cervina cluster group 1 was characterized by plants with low vegetative vigor (short plants, short stems, and late flowering), while M. cervina cluster group 2 contained the remaining acessions. PCA for both taxa showed that stem length was a very important characteristic/component in explaining variability.