Protoplasts of Page tangelo (Citrus reticulata Blanco×C. paradisi Macf.) cell suspension culture were electrically fused with mesophyll protoplasts isolated from trifoliate orange (Poncirus trifoliata (L.) Raf.)....Protoplasts of Page tangelo (Citrus reticulata Blanco×C. paradisi Macf.) cell suspension culture were electrically fused with mesophyll protoplasts isolated from trifoliate orange (Poncirus trifoliata (L.) Raf.). More than 150 plantlets regenerated after 4-5 months of culture. The regenerated plants were trifoliate with well developed root systems. Root_tip chromosome counting of more than 20 randomly selected plants revealed that they were all tetraploids (2n=4x=36). RAPD analysis of 7 randomly selected plants verified their hybridity. Inoculation of citrus Phytophthora parasitica Dastar toxin on leaves of somatic hybrids and both parental genotypes showed that Page tangelo was moderately susceptible, and trifoliate orange was highly resistant while the somatic hybrids were resistant. The potential of this somatic hybrid as rootstock is also discussed.展开更多
Leaf-derived protoplasts of Rough lemon (Citrus jambhiri Lush, 2n = 2x = 18) were electrofused with embryogenic suspension protoplasts of its relative, Microcitrus papuana Swingle (2n = 2x = 18), with an intention of ...Leaf-derived protoplasts of Rough lemon (Citrus jambhiri Lush, 2n = 2x = 18) were electrofused with embryogenic suspension protoplasts of its relative, Microcitrus papuana Swingle (2n = 2x = 18), with an intention of creating novel germplasm. Six plants were regenerated following protoplasts fusion. Cytological examination demonstrated that they were diploids with 18 chromosomes (2n = 2x = 18). RAPD (random amplified polymorphic DNA) analyses with six arbitrary 10-mer primers showed that the regenerated plants had identical band patterns to those of Rough lemon for primers OPA-07, OPAN-07, OPE-05 and OPA-08, Whereas for the other two primers, OPA-04 and OPS-13, bands specific to M. papuana could be detected in the regenerated plants. Cytological and RAPD analysis revealed that the regenerated plants were diploid somatic hybrids between M. papuana and Rough lemon. The putative hybrids were morphologically similar to Rough lemon. This is the first report on production of diploid somatic hybrid plants between citrus with its related genus via symmetric fusion.展开更多
Protoplasts of Valencia sweet orange ( Citrus sinensis Osb.),irradiated by X_ray with a dose rate of 3.8 krad/min for 45 min, were electrically fused with protoplasts of Murcott tangor ( C. reticulata×C. sin...Protoplasts of Valencia sweet orange ( Citrus sinensis Osb.),irradiated by X_ray with a dose rate of 3.8 krad/min for 45 min, were electrically fused with protoplasts of Murcott tangor ( C. reticulata×C. sinensis ) that were treated with 0.25 mmol/L iodoacetic acid for 15 min. It took nearly 15 months for the fusion_derived calli to develop into embryoids that were only originated in the medium of MT supplemented with 2% glycerol. The shoots were recalcitrant to rooting in the root_induction medium. In vitro grafting was employed to produce whole plants though one self_rooting plant was obtained. Cytological determination of root and shoot tips showed mainly diploid and aneuploid cells, together with few tetraploid cells in some plants. RAPD (random amplified polymorphism DNA) analysis with 10_mer primers demonstrated that bands specific to the fusion parents were detected in the regenerated plants, indicating that interspecific somatic hybrids have been obtained via protoplast asymmetric fusion in Citrus .展开更多
文摘Protoplasts of Page tangelo (Citrus reticulata Blanco×C. paradisi Macf.) cell suspension culture were electrically fused with mesophyll protoplasts isolated from trifoliate orange (Poncirus trifoliata (L.) Raf.). More than 150 plantlets regenerated after 4-5 months of culture. The regenerated plants were trifoliate with well developed root systems. Root_tip chromosome counting of more than 20 randomly selected plants revealed that they were all tetraploids (2n=4x=36). RAPD analysis of 7 randomly selected plants verified their hybridity. Inoculation of citrus Phytophthora parasitica Dastar toxin on leaves of somatic hybrids and both parental genotypes showed that Page tangelo was moderately susceptible, and trifoliate orange was highly resistant while the somatic hybrids were resistant. The potential of this somatic hybrid as rootstock is also discussed.
文摘Leaf-derived protoplasts of Rough lemon (Citrus jambhiri Lush, 2n = 2x = 18) were electrofused with embryogenic suspension protoplasts of its relative, Microcitrus papuana Swingle (2n = 2x = 18), with an intention of creating novel germplasm. Six plants were regenerated following protoplasts fusion. Cytological examination demonstrated that they were diploids with 18 chromosomes (2n = 2x = 18). RAPD (random amplified polymorphic DNA) analyses with six arbitrary 10-mer primers showed that the regenerated plants had identical band patterns to those of Rough lemon for primers OPA-07, OPAN-07, OPE-05 and OPA-08, Whereas for the other two primers, OPA-04 and OPS-13, bands specific to M. papuana could be detected in the regenerated plants. Cytological and RAPD analysis revealed that the regenerated plants were diploid somatic hybrids between M. papuana and Rough lemon. The putative hybrids were morphologically similar to Rough lemon. This is the first report on production of diploid somatic hybrid plants between citrus with its related genus via symmetric fusion.
基金TheNational Natural Science Foundation of China(3983026039625017)the International Foundation for Science(D/3001_1)
文摘Protoplasts of Valencia sweet orange ( Citrus sinensis Osb.),irradiated by X_ray with a dose rate of 3.8 krad/min for 45 min, were electrically fused with protoplasts of Murcott tangor ( C. reticulata×C. sinensis ) that were treated with 0.25 mmol/L iodoacetic acid for 15 min. It took nearly 15 months for the fusion_derived calli to develop into embryoids that were only originated in the medium of MT supplemented with 2% glycerol. The shoots were recalcitrant to rooting in the root_induction medium. In vitro grafting was employed to produce whole plants though one self_rooting plant was obtained. Cytological determination of root and shoot tips showed mainly diploid and aneuploid cells, together with few tetraploid cells in some plants. RAPD (random amplified polymorphism DNA) analysis with 10_mer primers demonstrated that bands specific to the fusion parents were detected in the regenerated plants, indicating that interspecific somatic hybrids have been obtained via protoplast asymmetric fusion in Citrus .
