Micropropagation, acclimatization, essential oil content and chemical composition of japanese mint genotypes

Japanese mint (Mentha arvensis L.) is an aromatic species originated from South China and its essential oil is rich in menthol, which is used in the pharmaceutical, food and cosmetic industries. The aim of this work was to develop a protocol for micropropagation and acclimatization of japanese mint genotypes and analyze the chemical composition of the essential oils from micropropagated and not micropropagated plants. Nodal segments are the most indicated for micropropagation of the M arvensis genotypes. The concentration of 4.4 mu M of IAA promoved higher number of shoots and leaves per explant of the MA701-02 genotype when compared with the others. The use of 4,4 mu M of IAA and 9,3 mu M of KIN + 8,9 mu M of BAP + 2,2 mu M of IAA resulted in major dry mass accumulation at genotype MA701-02. Major dry mass accumulation of genotype MA701-04 was promoted when 8,9 mu M BAP + 5,4 mu M NAA was used. The substrate coconut dust + 1 g L-1 of limestone + 12 g L-1 of Biosafra (R) (3-12-6) can be indicated to acclimatization of micropropagated plantlets of the tested japanese mint genotypes. Micropropagation did not change essential oil content and 17 chemical constituents were indentified, totalizing 92 to 99%.