Endogenous ethylene in indirect somatic embryogenesis of Medicago sativa L.

Abstract

Ethylene biosynthesis during different phases of somatic embryogenesis in Medicago sativa L. cv. Rangelander using two regeneration protocols, RPI and RPII, was studied. The highest ethylene production was detected during callus growth on induction medium in both regeneration protocols. Significantly less ethylene was produced by embryogenic suspension than by callus (RPII). Developing embryos synthesized higher amounts of ethylene than mature embryos. Production of ethylene was strongly limited by the availability of 1-aminocyclopropane-1-carboxylic acid and also by ACC-oxidase activity. However, removal of ethylene from culture vessels' atmosphere using KMnO 4 or HgClO 4 had no significant effect on callus growth, somatic embryo induction and development. Reducing of ethylene biosynthesis by aminoethoxyvinylglycine substantially decreased somatic embryo production and adversely affected their development, indicating ethylene requirement during proliferation and differentiation but not induction.

AGAMOUS-Like15 Promotes Somatic Embryogenesis in Arabidopsis and Soybean in Part by the Control of Ethylene Biosynthesis and Response

“…An ACO was previously reported as up-regulated during SE, although transcript accumulation was higher on the abaxial side than the adaxial side that forms embryos (Thibaud-Nissen et al, 2003). In other systems, ethylene has been shown to have a role in cotyledon development of B. napus microspore embryos (Hays et al, 2000) and in the development and conversion of alfalfa somatic embryos (Kepczynska et al, 2009;Kepczynska and Zielinska, 2011). In some situations, a suppression of embryogenesis with ethylene is observed (for review, see Jiménez and Thomas, 2006), and a number of systems show enhanced SE by the addition of AgNO 3 to medium (for review, see Kumar et al, 2009).…”

Disturbance of ethylene biosynthesis and perception during somatic embryogenesis in Medicago sativa L. reduces embryos’ ability to regenerate

“…When using a regeneration system in which two main phases of SE, induction and differentiation, are separated by an additional step of embryogenic tissue proliferation, we observed that ethylene production during callus growth, proliferation of cell suspension and embryo development in Medicago sativa L. cv. Rangelander are greatly altered during SE (Kępczyńska et al 2009a). Ethylene accumulation in vessels was correlated with the ability of tissues to produce ACC and to convert it into ethylene.…”

65 years of in vitro culture in Poland

“…When investigating the phytohormonal regulation of somatic embryogenesis, E. Kępczyńska from Szczecin University evaluated the influence of gibberelins [113], ABA and MeJA [114,115], ethylene [116] and auxins on specific phases of SE (i.e. induction, proliferation, differentiation, maturation and embryo regeneration) in two model species: Medicago sativa and M. truncatula.…”

“…induction, proliferation, differentiation, maturation and embryo regeneration) in two model species: Medicago sativa and M. truncatula. She found that endogenous jasmonates and ABA (natural growth inhibitors) restrict proliferation and growth of proembryogenic callus but stimulate germination and conversion of alfalfa embryos [116]. She continues her work on increasing the rates of germination and conversion of embryos of cultivated plants, aiming to formulate the optimal conditions for somatic embryo production.…”