Polyethylene glycol and abscisic acid improve maturation and regeneration of Panax ginseng somatic embryos

Abstract

Embryogenic culture was initiated from mature zygotic embryos of Panax ginseng. Multiple somatic embryos formed and proliferated on Murashige and Skoog medium supplemented with 2,4-dichlorophenoxyacetic acid (2.26 microM) and kinetin (0.046 microM). Mature as well as immature somatic embryos grew into plantlets lacking roots on the same media. Histomorphological analysis of somatic embryos treated with abscisic acid (ABA) and polyethylene glycol (PEG 4000) showed a slight improvement in the root meristem organization of torpedo-stage embryos (embryos were more compact and their cells exhibited a lower degree of vacuolation). Shoot regeneration of non-treated somatic embryos was 31% while that for somatic embryos treated with PEG 4000 and ABA was 70%. Moreover, 75% of plants regenerated from PEG- and ABA-treated embryos formed roots while plants from non-treated embryos did not form roots.

An efficient regeneration system via direct and indirect somatic embryogenesis for the medicinal tree Murraya koenigii

“…Low plant recovery rates are due to poor embryo quality and the lack of maturation and desiccation tolerance (Etienne et al 1993). In general, maturation of somatic embryos can be achieved through treatments with cold temperature, gibberellic acid, abscisic acid, and/or permeating osmotica (high concentrations of sugars, sugar alcohols, amino acids) or non-permeating osmotica [polyethylene glycol (PEG) and dextran] which induce water stress in the culture medium (Langhansová et al 2004). The normal somatic embryos, irrespective of their origin, suitably germinated in 1/2 MS basal medium with or without PGRs.…”

The role of abscisic acid in plant tissue culture: a review of recent progress

“…ABA not only promotes the transition of somatic embryos from the proliferation to the maturation phase (Langhansova et al 2004), but it has also been used to enhance embryo quality by increasing desiccation tolerance and preventing precocious germination (Ammirato 1977;Senaratna et al 1989;Attree et al 1990;Lecouteux et al 1993;Capuana and Debergh 1997;Li et al 1997;Robichaud et al 2004;Vahdati et al 2008;Rai et al 2008a; Fig. 2).…”

Germination and conversion of somatic embryos derived from mature Quercus robur trees: the effects of cold storage and thidiazuron

“…However, the rooting of shoots produced by somatic embryos that fail to convert into whole plants constitutes a viable alternative that can considerably improve the efficiency of oak embryogenic lines with low conversion capacity. The combined strategy based on somatic embryo conversion to the extent that it is possible, and/or rooting the shoots of unconverted embryos that produce them, has been reported in several species with poor embryo conversion rates, including Cercis canadensis (Distabanjong and Geneve 1997), Panax ginseng (Langhansova et al 2004), Garcimnia indica (Thengane et al 2006) and Ceratonia siliqua (Canhoto et al 2006).…”