Effect of nanosilver on the in vitro propagation of Merr.

Abstract

Asarum glabrum Merr. is a rare and precious medicinal herb in the Red Data Book of Vietnam with the rating of "endangered". This species naturally distributed in some areas of the northern mountains with small amount of individuals and increasingly declined, therefore the propagation of Asarum glabrum Merr. for conservation is extremely necessary. In this study, nanosilver (nAg) is used as a surface sterilisation for the rhizoform samples with different concentrations: 75, 100, 125, 150 and 200 ppm within 20, 30, 40, 50 and 60 minutes. The explants were sterilised by nAg at the concentration of 150 ppm within 40 minutes, obtaining the highest percentage of alive and aseptic explants (70.32% and 65.34%, respectively) after 4 weeks of culture. The explants were cultured on MS media added with 20 g/l sucrose, 8.5 g/l agar, 1 mg/l BAP and containing different concentrations of nAg: 0, 2, 4, 6, 8 ppm. The results showed that the medium supplemented with 6 ppm nAg was optimal for the induction of callus obtained the highest percentage of callus (69.34%) and the average number of shoots per samples reached 1.58 after 4 weeks. The MS media supplemented with 20 g/l sucrose, 8.5 g/l agar, 2 mg/l BAP and 6 ppm nAg was the best for multiplying with the average height of shoots reached 2.81 and 1.78 cm (respectively) after 6 weeks of rapid propagation.