Influence of explant,temperature and different culture vessels on in vitro culture for germplasm maintenance of four mint accessions

Two experiments were conducted with four accessions of mint (Mentha spp.) on MS medium for their in vitro performance. In the first experiment apical and nodal explants were cultured at both 20 °C and 25 °C. Data was recorded at second and at fifth week. Both apical and nodal explants of mint showed better leaf production at 25 °C than 20 °C. Nodal explants of mint cultured at 25 °C in both cultivation periods exhibited the highest number of leaves. In the second experiment apical explants were cultured in four different culture vessels viz., industrial glass jar (IG), magenta vessel (MV), Erlenmeyer flask (EF) and culture tube with 1(CT1) and 2(CT2) explants at 25 °C for 6 weeks. The highest weight loss from the media, evapo-transpiration and fresh weight gain were recorded in IG and next in MV. The lowest weight loss from the media and fresh weight gain both were found in CT2. However the lowest evapo-transpiration was noted in EF. The highest numbers of leaves were recorded from MV. Without explants, depletion of medium and increase of headspace were both higher in IG than in the other vessels. Overall, Magenta vessel GA 7 showed the best in vitro performance.