In this paper,a protocol for efficient shoot regeneration was successfully developed from hypocotyl explants of Euonymus fortunei var.radicans.Some factors that influenced shoot regeneration such as different combinat...In this paper,a protocol for efficient shoot regeneration was successfully developed from hypocotyl explants of Euonymus fortunei var.radicans.Some factors that influenced shoot regeneration such as different combinations of plant growth regulators,types of medium and inoculation ways were studied in order to establish an efficient plant regeneration for transformation.The results showed that hypocotyl explants were horizontally cultured on a basic medium composed of MS medium supplemented with 0.5 mg·L-1 BAP and 0.01 mg·L-1 NAA for induction and development of adventitious shoots.Ninety-four percent of regeneration frequency and 5.1 shoots per explants were obtained after 30 days of culture.Regenerated shoots proliferated efficiently on a shoot multiplication medium consisting of MS medium containing 1.0 mg·L-1 BAP and 0.1 mg·L-1 NAA.Microshoots were rooted on a rooting medium made up of MS medium enriched with 0.5 mg·L-1 IBA and 0.5 mg·L-1 IAA.After hardening,90% of plants were successfully established under greenhouse conditions.Histological observation revealed that shoot primordium originated from subepidermal cells of hypocotyl explants and directly developed into adventitious shoots without callus formation.展开更多
Various individual organs (tepal, flower bud, inflorescence branch, inflorescence, adult vegetative bud and juvenile vegetative bud) were directly regenerated respectively by callus in Dracaena fragrans cv. massangean...Various individual organs (tepal, flower bud, inflorescence branch, inflorescence, adult vegetative bud and juvenile vegetative bud) were directly regenerated respectively by callus in Dracaena fragrans cv. massangeana Hort. During the regeneration of these individual organs some regularity phenomena were observed. Firstly, the kind range of the individual organs, which are directly regenerated in vitro, is in close relationship to the differentiated stages of the organs used for explant excision during plant ontogeny. The explants excised from the epigeous organ that is differentiated at some stage (stage A) during plant ontogeny must be able to separately regenerate all of those individual epigeous organs: ones differentiated slightly later than the stage A, ones differentiated at the stage A and all ones differentiated earlier than the stage A. Secondly, within this range which kind of organ is regenerated depends on the exogenous auxin concentrations in medium. With the gradual increase of 2,4-D concentration from 0.005 mg/L to 0.5 mg/L, the kinds of regenerated organs will change by the order as follows: vegetative bud, inflorescence, inflorescence branch, flower bud, tepal. These regularities will be able to be used for inducing the direct regeneration of a given epigeous organ in angiosperms.展开更多
基金supported by Beijing Municipal Science and Technology Commission(H020620110130)
文摘In this paper,a protocol for efficient shoot regeneration was successfully developed from hypocotyl explants of Euonymus fortunei var.radicans.Some factors that influenced shoot regeneration such as different combinations of plant growth regulators,types of medium and inoculation ways were studied in order to establish an efficient plant regeneration for transformation.The results showed that hypocotyl explants were horizontally cultured on a basic medium composed of MS medium supplemented with 0.5 mg·L-1 BAP and 0.01 mg·L-1 NAA for induction and development of adventitious shoots.Ninety-four percent of regeneration frequency and 5.1 shoots per explants were obtained after 30 days of culture.Regenerated shoots proliferated efficiently on a shoot multiplication medium consisting of MS medium containing 1.0 mg·L-1 BAP and 0.1 mg·L-1 NAA.Microshoots were rooted on a rooting medium made up of MS medium enriched with 0.5 mg·L-1 IBA and 0.5 mg·L-1 IAA.After hardening,90% of plants were successfully established under greenhouse conditions.Histological observation revealed that shoot primordium originated from subepidermal cells of hypocotyl explants and directly developed into adventitious shoots without callus formation.
文摘Various individual organs (tepal, flower bud, inflorescence branch, inflorescence, adult vegetative bud and juvenile vegetative bud) were directly regenerated respectively by callus in Dracaena fragrans cv. massangeana Hort. During the regeneration of these individual organs some regularity phenomena were observed. Firstly, the kind range of the individual organs, which are directly regenerated in vitro, is in close relationship to the differentiated stages of the organs used for explant excision during plant ontogeny. The explants excised from the epigeous organ that is differentiated at some stage (stage A) during plant ontogeny must be able to separately regenerate all of those individual epigeous organs: ones differentiated slightly later than the stage A, ones differentiated at the stage A and all ones differentiated earlier than the stage A. Secondly, within this range which kind of organ is regenerated depends on the exogenous auxin concentrations in medium. With the gradual increase of 2,4-D concentration from 0.005 mg/L to 0.5 mg/L, the kinds of regenerated organs will change by the order as follows: vegetative bud, inflorescence, inflorescence branch, flower bud, tepal. These regularities will be able to be used for inducing the direct regeneration of a given epigeous organ in angiosperms.
