title: Development of an Agrobacterium-mediated transformation method for pear (Pyrus communis L.) with leaf-section and axillary shoot-meristem explants.
abstract: We have developed a new Agrobacterium-mediated transformation method for the low-frequency-regenerating pear (Pyrus communis L.) cvs. Silver bell and La France. Leaf sections derived from in vitro shoots were initially used for the transformation procedure. Under optimum transformation conditions, which included culture and selection on 30 mg/l kanamycin (Km) combined with 500 mg/l sulbenicillin, a 3.2% transformation efficiency was obtained for cv. Silver bell, but no transformants of La France were obtained because of the very low regeneration frequency. Axillary shoot meristems were then examined as potential explants for La France. Selection in 5 mg/l Km and 375 mg/l carbenicillin resulted in transformed shoots being produced at an efficiency of 4.8%, and the apparent white Km-sensitive shoots were not formed during a 2-year subculture on micropropagation medium containing 50 mg/l Km. Therefore, transformations using axillary shoot meristems may be an alternative method for pear cultivars recalcitrant to regeneration from leaf sections.
authors.affiliation: Yamagata Prefectural Horticultural Experiment Station, 423 Shimaminami, Sagae, Yamagata 991-0043, Japan. matsudanar@pref.yamagata.jp
authors.forename: Narumi
authors.initials: N
authors.lastname: Matsuda
authors.forename: Mei
authors.initials: M
authors.lastname: Gao
authors.forename: Kanji
authors.initials: K
authors.lastname: Isuzugawa
authors.forename: Tadashi
authors.initials: T
authors.lastname: Takashina
authors.forename: Koichi
authors.initials: K
authors.lastname: Nishimura
mesh_terms: D016960:Agrobacterium tumefaciens; D005818:Genetic Engineering / Q000379:methods*; D007612:Kanamycin; D018515:Plant Leaves / Q000235:genetics / Q000254:growth & development; D018520:Plant Shoots / Q000235:genetics / Q000254:growth & development; D030821:Plants, Genetically Modified; D031989:Pyrus / Q000235:genetics* / Q000254:growth & development; D014170:Transformation, Genetic
chemical_list: D007612:Kanamycin