High frequency somatic embryogenesis and plant regeneration of interspecific ginseng hybrid between Panax ginseng and Panax quinquefolius

Abstract

BackgroundInterspecific ginseng hybrid, Panax ginseng × Panax quenquifolius (Pgq) has vigorous growth and produces larger roots than its parents. However, F1 progenies are complete male sterile. Plant tissue culture technology can circumvent the issue and propagate the hybrid.MethodsMurashige and Skoog (MS) medium with different concentrations (0, 2, 4, and 6 mg/L) of 2,4-dichlorophenoxyacetic acid (2,4-D) was used for callus induction and somatic embryogenesis (SE). The embryos, after culturing on GA3 supplemented medium, were transferred to hormone free ½ Schenk and Hildebrandt (SH) medium. The developed taproots with dormant buds were treated with GA3 to break the bud dormancy, and transferred to soil. Hybrid Pgq plants were verified by random amplified polymorphic DNA (RAPD) and inter simple sequence repeat (ISSR) analyses and by LC-IT-TOF-MS.ResultsWe conducted a comparative study of somatic embryogenesis (SE) in Pgq and its parents, and attempted to establish the soil transfer of in vitro propagated Pgq tap roots. The Pgq explants showed higher rate of embryogenesis (~56% at 2 mg/L 2,4-D concentration) as well as higher number of embryos per explants (~7 at the same 2,4-D concentration) compared to its either parents. The germinated embryos, after culturing on GA3 supplemented medium, were transferred to hormone free ½ SH medium to support the continued growth and kept until nutrient depletion induced senescence (NuDIS) of leaf defoliation occurred (4 months). By that time, thickened tap roots with well-developed lateral roots and dormant buds were obtained. All Pgq tap roots pretreated with 20 mg/L GA3 for at least a week produced new shoots after soil transfer. We selected the discriminatory RAPD and ISSR markers to find the interspecific ginseng hybrid among its parents. The F1 hybrid (Pgq) contained species specific 2 ginsenosides (ginsenoside Rf in P. ginseng and pseudoginsenosides F11 in P. quinquefolius), and higher amount of other ginsenosides than its parents.ConclusionMicropropagation of interspecific hybrid ginseng can give an opportunity for continuous production of plants.

Phalaenopsis LEAFY COTYLEDON1-Induced Somatic Embryonic Structures Are Morphologically Distinct From Protocorm-Like Bodies

“…For example, somatic embryos are used as transformation materials for alfalfa, American chestnut, cassava, cotton, grapevine, maize, mango, melon, Norway spruce, papaya, rose, tea tree, and walnut (Umbeck et al, 1987; Mcgranahan et al, 1988; Robertson et al, 1992; Fitch et al, 1993; Li et al, 1996; Brettschneider et al, 1997; Trinh et al, 1998; Mondal et al, 2001; Akasaka-Kennedy et al, 2004; Chavarri et al, 2004; Li et al, 2006; Polin et al, 2006; Vergne et al, 2010). In addition, the regeneration capacity of somatic embryos has made somatic embryogenesis a common method through which to clonally propagate economically important trees or herbal plants (Joshee et al, 2007; Nordine et al, 2014; Guan et al, 2016; Kim et al, 2019).…”

Recent Advances in the Tissue Culture of American Ginseng (Panax quinquefolius)

“…[66,67] Somatic embryo-genesis is an important and reliable regeneration method for establishing true-type clones of many plant species. [68,69] Kim et al [70] conducted a tissue culture study on hybrid Asian/American ginseng (Pgq) and found the optimal condition to induce callus and embryogenesis was MS medium containing 2 mg/L 2,4-D. The Pgq explants produced somatic embryos on MS medium after eight weeks of culture, and somatic embryos germinated rapidly on Schenk and Hilderbrandt (SH) medium containing 5 mg/L GA within two weeks.…”

“…Kim et al [70] . conducted a tissue culture study on hybrid Asian/American ginseng (Pgq) and found the optimal condition to induce callus and embryogenesis was MS medium containing 2 mg/L 2,4‐D.…”

Genetic Composition of Korean Ginseng Germplasm by Collection Area and Resource Type

“…Kim et al [56] studied the tissue culture of F1 plant propagation in a ginseng hybrid (P. ginseng × P. quinquefolius) to solve the seedless problem. In addition, some research groups have attempted mutation breeding using irradiation or chemicals, but they did not develop new ginseng varieties; they did confirm plants with high ginsenosides [59][60][61][62][63].…”