Somatic Embryogenesis of Tuberose (Agave amica L.) was Improved by Milk as a Potential Biostimulant in Plant Tissue Culture

In this study, an efficient in vitro method was established for indirect somatic embryogenesis of tuberose from pedicel-derived calluses on MS medium. The effects of ۲,۴-D, NAA, BAP, and ABA on callus induction, callus growth, embryogenic callus formation, embryo maturation, and plantlet regeneration were evaluated. Combination of ۰.۵ mg L-۱ ۲,۴-D + ۰.۵ mg L-۱ NAA resulted in the highest percentage of callus induction (۱۰۰%) and callus quality. The highest average of callus growth was achieved at ۱ mg L-۱ ۲,۴-D + ۱ mg L ۱ BAP. Embryogenic calluses were induced on the media containing ۱ mg L-۱ ۲,۴-D after ۹۰ days of subculturing. The highest number of matured somatic embryos per petri dish (۸۱) and callus greening were observed on the medium containing ۱ mg L-۱ ABA + ۴۵ g L-۱ maltose. Further germination of embryos was observed on MS medium containing ۱۰ to ۱۵ ml L-۱ goat colostrum and embryos with leaves regenerated after ۹۰ days. Beside induction of osmotic pressure, colostrum is a rich source of organic nitrogen and calcium which play key roles in somatic embryogenesis. The whole plantlets were achieved after ۶۰ days of subculturing on the media containing IBA (۰.۷۵ mg L-۱) with a survival rate of ۸۸%. In conclusion, the present study provides a suitable somatic embryogenesis system which may serve in micropropagation, genetic transformation, and ploidy manipulation of tuberose.

Keywords:

Bulbous plant , Indirect somatic embryo , Micropropagation , Organic additive , plant tissue culture