Environmentally safe in vitro regeneration protocol for Curcuma, Kaempferia and Zingiber

Abstract

This study is a pioneer report on the development of an environmentally safe in vitro regeneration protocol for Curcuma, Kaempferia and Zingiber. The germplasm of the species was collected from Myanmar, a Southeast Asian country, rich in unexplored Zingiberaceae genetic resources.  Rhizome buds were directly regenerated on the Murashige and Skoog medium containing a growth regulator, 6-benzyladenine and a commercial fungicide, Benlate (50% of Benomyl). The pre-treatment protocol did
not contain HgCl2, a toxic pollutant for Curcuma amada, Curcuma longa, Zingiber barbatum and Kaempferia galanga. Plantlets were regenerated from the buds without any intervention of the callus phase. The contamination free survival of the bud explants from Curcuma, Zingiber and Kaempferia was more than 75, 57 and 53%, respectively. Buds from immature rhizomes were difficult to regenerate on the media, as well as resulted in higher contamination percentages while the buds from mature
rhizomes efficiently regenerated with very few contamination percentages. The contamination was in the range of 0 to 39% among the different accessions. This was also the first report of direct in vitro regeneration of plantlets from Z. barbatum bud explants. The protocol was cost-beneficial, time saving and effective for the conservation of Zingiberaceae genetic resources.

Key words: Conservation, regeneration, Zingiberaceae, tissue culture, Curcuma, Zingiber, Myanmar.