Optimization of surface sterilization protocol, induction of axillary shoots regeneration in Zingiber zerumbet (L.) Sm. as affected by season

Abstract

The investigation was undertaken to standardize the protocol for the micropropagation of Zingiber zerumbet (L.) Sm. Rhizome buds were surface sterilized using 0.1% mercuric chloride for 15 min, 100 μg/ml fungicide (Carbendazim) and 70% ethanol for different exposure timings. Among the tested sterilization steps, treatment of rhizome with fungicide for 30 min and 70% ethanol for 10 min, 0.1% HgCl2 shows the highest bud break of 83.6% and contamination of 18.71%. However, increasing the exposure of 70% for 15 min decreases the contamination to 16.53% but the bud break also decreased to 75.23%. Increasing the exposure time, rhizome tissues were damaged as alcohol may have been toxic to the tissues due to longer exposure time. Three seasons of explants collection and inoculation were tested: November–Feb, March–June and July–Oct. In the present study, a more intensive shoot initiation was observed in the summer period than in the winter season. The seasonal period of March–June proves to be the most suitable and favourable season for in vitro shoot initiation than the rest of the season. Thus, season plays an important role in plant tissue culture study. There are no published data on effect of rhizome collection time and different sterilization methods on induction of shoots in Zingiberaceae plant, Z. zerumbet, and hence this is the first report of its kind.