For the mass production of Koelreuteria bipinnata var. integrifoliola with selected, hybrid or genetically engineered genotypes, one potentially desirable propagation strategy is based on embryo culture. The immature ...For the mass production of Koelreuteria bipinnata var. integrifoliola with selected, hybrid or genetically engineered genotypes, one potentially desirable propagation strategy is based on embryo culture. The immature embryo development in vitro from K. bipinnata var. integrifoliola was studied under different conditions of embryo age, basic culture media and plant growth regulators. The results show that： 1） germination rate of grade 3 embryos in immature seeds with 0.6-0.8 cm diameter was 98.9%. The germination rate of grade 2 embryos in immature seeds with 0.4-0.6 cm diameter was 77,8% and the germination rate of grade 1 embryos in immature seeds with 0.4 cm diameter was 15.6%. 2） The amounts of macroelements in MS medium had no clear effect on the germination rate of immature grade 3 embryos and had a modest effect on plantlet growth, where the best medium was MS or 1/2 MS. The rates were all greater than 90%. 3） The germination rate of grade 3 embryos was greater than 87% when the medium contained a low concentration of NAA or no plant growth regulators at all and decreased markedly when BAP alone or BAP and NAA together were added to the media. We suggest that in vitro culture of immature embryos from K. bipinnata vat. integrifoliola can be enhanced when a small amount of plant growth regulators is added. The addition of BAP has an adverse reaction to the germination and development of immature embryos.展开更多
Somatic embryogenesis ofKoelreuteria bipinnata var. integrifoliola was observed, plantlet formation in different types of somatic embryos was studied and the effect of abnormal embryos on plantlet formation was identi...Somatic embryogenesis ofKoelreuteria bipinnata var. integrifoliola was observed, plantlet formation in different types of somatic embryos was studied and the effect of abnormal embryos on plantlet formation was identified. Results show that somatic embryos of K. bipinnata var. integrifoliola include normal embryos, embryos with abnormal cotyledons, vitrified embryos, albino embryos, secondary embryos, linked embryos, embryos with abnormal growing points and embryos with expanding hypocotyl. After 40 d of callus culture, the response of normal somatic embryos from K. bipinnata var. integrifoliola was 26.7%, embryos with abnormal cotyledon 30.3% while other types of somatic embryos were below the 20% level. Most of normal embryos developed into plantlets and plantlet formation reached 94.9%. But the percentage of plantlet formation decreased apparently in abnormal embryos： the number of embryos with abnormal cotyledon declined to 76.1%, that of linked embryos to 47.4% and other types of abnormal embryos to below the 20% level. Albino embryos and embryos with abnormal growing point did not develop at all into plantlets. Embryos with abnormal cotyledons, linked embryos and embryos with abnormal growing points were observed during early stages of somatic embryogenesis, but vitrified, secondary and albino embryos and calli of embryos were observed at later stages. Increasing sucrose concentrations can decrease the occurrence of vitrified embryos, but the number of albino embryos decreased with an in- creasing in sucrose concentration.展开更多
基金supported by the Key Laboratory of Genetics and Breeding in Forest Trees and Ornamental Plants of Ministry of Education, Beijing Forestry University, China (05–04)
文摘For the mass production of Koelreuteria bipinnata var. integrifoliola with selected, hybrid or genetically engineered genotypes, one potentially desirable propagation strategy is based on embryo culture. The immature embryo development in vitro from K. bipinnata var. integrifoliola was studied under different conditions of embryo age, basic culture media and plant growth regulators. The results show that： 1） germination rate of grade 3 embryos in immature seeds with 0.6-0.8 cm diameter was 98.9%. The germination rate of grade 2 embryos in immature seeds with 0.4-0.6 cm diameter was 77,8% and the germination rate of grade 1 embryos in immature seeds with 0.4 cm diameter was 15.6%. 2） The amounts of macroelements in MS medium had no clear effect on the germination rate of immature grade 3 embryos and had a modest effect on plantlet growth, where the best medium was MS or 1/2 MS. The rates were all greater than 90%. 3） The germination rate of grade 3 embryos was greater than 87% when the medium contained a low concentration of NAA or no plant growth regulators at all and decreased markedly when BAP alone or BAP and NAA together were added to the media. We suggest that in vitro culture of immature embryos from K. bipinnata vat. integrifoliola can be enhanced when a small amount of plant growth regulators is added. The addition of BAP has an adverse reaction to the germination and development of immature embryos.
基金supported by the Foundation for Science and Technology Research and Development Program of Hebei Province (09225511)the Project of the Key Laboratory of Genetics and Breeding in Forest Trees and Ornamental Plants of the Ministry of Education, Beijing Forestry University, China (05– 04)
文摘Somatic embryogenesis ofKoelreuteria bipinnata var. integrifoliola was observed, plantlet formation in different types of somatic embryos was studied and the effect of abnormal embryos on plantlet formation was identified. Results show that somatic embryos of K. bipinnata var. integrifoliola include normal embryos, embryos with abnormal cotyledons, vitrified embryos, albino embryos, secondary embryos, linked embryos, embryos with abnormal growing points and embryos with expanding hypocotyl. After 40 d of callus culture, the response of normal somatic embryos from K. bipinnata var. integrifoliola was 26.7%, embryos with abnormal cotyledon 30.3% while other types of somatic embryos were below the 20% level. Most of normal embryos developed into plantlets and plantlet formation reached 94.9%. But the percentage of plantlet formation decreased apparently in abnormal embryos： the number of embryos with abnormal cotyledon declined to 76.1%, that of linked embryos to 47.4% and other types of abnormal embryos to below the 20% level. Albino embryos and embryos with abnormal growing point did not develop at all into plantlets. Embryos with abnormal cotyledons, linked embryos and embryos with abnormal growing points were observed during early stages of somatic embryogenesis, but vitrified, secondary and albino embryos and calli of embryos were observed at later stages. Increasing sucrose concentrations can decrease the occurrence of vitrified embryos, but the number of albino embryos decreased with an in- creasing in sucrose concentration.
