title: Auxin synthesis-encoding transgene enhances grape fecundity.
abstract: Grape (Vitis vinifera) yield is largely dependent on the fecundity of the cultivar. The average number of inflorescences per shoot (i.e. shoot fruitfulness) is a trait related to fecundity of each grapevine. Berry number and weight per bunch are other features affecting grape yield. An ovule-specific auxin-synthesizing (DefH9-iaaM) transgene that increases the indole-3-acetic acid content of grape transgenic berries was transformed into cultivars Silcora and Thompson Seedless, which differ in the average number of inflorescences per shoots. Thompson Seedless naturally has very low shoot fruitfulness, whereas Silcora has medium shoot fruitfulness. The average number of inflorescences per shoot in DefH9-iaaM Thompson Seedless was doubled compared to its wild-type control. Berry number per bunch was increased in both transgenic cultivars. The quality and nutritional value of transgenic berries were substantially equivalent to their control fruits. The data presented indicate that auxin enhances fecundity in grapes, thus enabling to increase yield with lower production costs.
authors.affiliation: Dipartimento Scienze Ambientali e delle Produzioni Vegetali, Marche Polytechnic University, 60131 Ancona, Italy.
authors.forename: Elisa
authors.initials: E
authors.lastname: Costantini
authors.forename: Lucia
authors.initials: L
authors.lastname: Landi
authors.forename: Oriana
authors.initials: O
authors.lastname: Silvestroni
authors.forename: Tiziana
authors.initials: T
authors.lastname: Pandolfini
authors.forename: Angelo
authors.initials: A
authors.lastname: Spena
authors.forename: Bruno
authors.initials: B
authors.lastname: Mezzetti
mesh_terms: D017343:Genes, Plant; D007210:Indoleacetic Acids / Q000378:metabolism*; D008969:Molecular Sequence Data; D009753:Nutritive Value; D016133:Polymerase Chain Reaction; D019076:Transgenes; D027843:Vitis / Q000378:metabolism / Q000502:physiology*
chemical_list: D007210:Indoleacetic Acids