Gynogenesis in gentians (Gentiana triflora, G. scabra): production of haploids and doubled haploids

Abstract

Gynogenesis was investigated on gentian (Gentiana triflora, G. scabra and their hybrids), which is an important ornamental flower. When unfertilized ovules were cultured in 1/2 NLN medium containing a high concentration of sucrose (100 g/l), embryo-like structures (ELS) were induced. Although genotypic variation was observed in ELS induction, all four genotypes produced ELSs ranging from 0.93 to 0.04 ELSs per flower bud. The ovules collected from flower buds of later stages (just before anthesis or flower anthesis) tended to exhibit higher response. The dark culture condition produced more than four times as many ELSs than in 16-h light condition. A significant number of plantlets were directly regenerated from ELSs on MS regeneration medium. The ploidy levels of 179 regenerated plants were determined by flow cytometry, revealing that the majority of them were diploid (55.9%) and haploid (31.3%). When a total of 54 diploid plants were examined by molecular genetic markers, 52 (96.3%) were considered as doubled haploids (DHs). This is the first report showing successful gynogenesis in gentian. The production of haploids and DHs by unfertilized ovule culture opens a novel prospect in gentian F1 hybrid breeding.

Evaluation of Factors Affecting Embryo-like Structure and Callus Formation in Unpollinated Ovary Culture of Cucumber (Cucumis sativus)

“…These homozygous doubled haploids have been induced via either androgenesis (pollen or anther culture) or gynogenesis (ovule or ovary culture) processes, or induced by pollination with irradiated pollen (Islam, 2010;Chen et al, 2011;Lazaridou et al, 2011;Gałązka and Niemirowicz-Szczytt, 2013). In several plants, including sugar beet and gentians, in vitro culture of unpollinated ovules or ovaries have been reported to be more efficient in haploid and doubled haploid production than pollen or anther culture (Gürel et al, 2000;Chen et al, 2011;Doi et al, 2011). Haploid or doubled haploid plants are regenerated through either the formation of ELS directly on ovules or the formation of ELS or shoots on calli induced from ovules/ovaries (Bhojwani and Razdan, 1996;Reed, 2005).…”

Development of haploid embryos and plants of Lactuca sativa induced by distant pollination with Helianthus annuus and H. tuberosus

“…Gynogenesis this method allows haploids to be obtained from an unfertilised egg cell or synergids (Mól 1999;Musiał et al 2005) through the culturing of unfertilised ovules or ovaries, such as in Beta vulgaris L. (Gośka et al 2004), Gentiana triflora Pall. (Doi et al 2011) or Allium cepa (Musiał et al 2001).…”

Haploid and Doubled Haploid Plant Production in Gentian (Gentiana spp.)

“…Of these factors, genotypic variations in response to gynogenesis have been reported in many plants. However, in gentians, Doi et al (2011) reported that ELSs were obtained from all tested genotypes and could develop into plantlets, though genotypic variations were found in ELS production (0.04-0.93 ELSs per flower bud). These authors demonstrated that G. scabra and the hybrid G. triflora × G. scabra, which is a recalcitrant species in anther culture, produced many ELSs via gynogenesis.…”