title: Nectar production and transportation in the nectaries of the female Cucumis sativus L. flower during anthesis.
abstract: In an effort to gain a greater understanding of nectar production, we studied the dynamic mechanisms of starch accumulation and transformation and nectar transportation in the Cucumis sativus L. female flower. Starch, which is the main precursor of nectar, accumulates in the epidermis and underlying parenchyma, with the most active accumulation occurring in the parenchyma cells within 3 days prior to anthesis. Thereafter, the starch was successively hydrolyzed and the hydrolyte was transported from the amyloplasts to vacuoles, suggesting that amyloplasts and vacuoles are the centers of nectar production. In addition, we observed few plasmodesmata and the presence of invaginated plasmalemma and electron-dense material in the intercellular spaces, suggesting that the apoplast system is involved in nectar transportation in an ATPase-dependent fashion.
authors.affiliation: Peking-Yale Joint Center for Plant Molecular Genetics and Agrobiotechnology, College of Life Sciences, Peking University, Beijing, People's Republic of China.
authors.forename: Yi-Ben
authors.initials: YB
authors.lastname: Peng
authors.forename: Yi-Qin
authors.initials: YQ
authors.lastname: Li
authors.forename: Yu-Jin
authors.initials: YJ
authors.lastname: Hao
authors.forename: Zhi-Hong
authors.initials: ZH
authors.lastname: Xu
authors.forename: Shu-Nong
authors.initials: SN
authors.lastname: Bai
mesh_terms: D001692:Biological Transport; D018553:Cucumis sativus / Q000502:physiology* / Q000648:ultrastructure; D035264:Flowers / Q000502:physiology* / Q000648:ultrastructure; D006180:Proton-Translocating ATPases / Q000032:analysis; D013213:Starch / Q000096:biosynthesis; D014617:Vacuoles / Q000378:metabolism / Q000648:ultrastructure
chemical_list: D013213:Starch; D006180:Proton-Translocating ATPases