Nectaries and reproductive biology of croton sarcopetalus (euphorbiaceae)

dc.contributor.authorFreitas, Leandro [UNESP]
dc.contributor.authorBernardello, Gabriel
dc.contributor.authorGaletto, Leonardo
dc.contributor.authorPaoli, Adelita A. S. [UNESP]
dc.contributor.institutionUniversidade Estadual Paulista (UNESP)
dc.contributor.institutionCONICET-Universidad Nacional de Córdoba
dc.description.abstractFlower morphology, nectary structure, nectar chemical composition, breeding system, floral visitors and pollination were analysed in Croton sarcopetalus, a diclinous-monoecious shrub from Argentina. Male flowers have five receptacular nectaries, with no special vascular bundles, that consist of a uniserial epidermis with stomata subtended by a secretory parenchyma. Female flowers bear two different types of nectaries: inner (IN) and outer (ON) floral nectaries. IN, five in all, are structurally similar to the nectaries of male flowers. The five ON are vascularized, stalked, and composed of secretory, column-shaped epidermal cells without stomata subtended by secretory and ground parenchyma. In addition, ON act as post-floral nectaries secreting nectar during fruit ripening. Extrafloral nectaries (EFN) are located on petioles, stipules and leaf margins. Petiolar EFN are patelliform, stalked and anatomically similar to the ON of the female flower. Nectar sampled from all nectary types is hexose dominant, except for the ON of the female flower at the post-floral stage that is sucrose dominant. The species is self-compatible, but geitonogamous fertilization is rarely possible because male and female flowers are not usually open at the same time in the same individual, i.e. there is temporal dioecism. Flowers are visited by 22 insect species, wasps being the most important group of pollinators. No significant differences were found in fruit and seed set between natural and hand pollinated flowers. This pattern indicates that fruit production in this species is not pollen/pollinator limited and is mediated by a wide array of pollinators. © 2001 The Linnean Society of London.en
dc.description.affiliationDepartamento de Botânica UNESP, Caixa Postal 199, 13506-900 Rio Claro, SP
dc.description.affiliationInstituto Multidisciplinario de Biología Vegetal CONICET-Universidad Nacional de Córdoba, Casilla de Correo 495, 5000 Córdoba
dc.description.affiliationUnespDepartamento de Botânica UNESP, Caixa Postal 199, 13506-900 Rio Claro, SP
dc.identifier.citationBotanical Journal of the Linnean Society, v. 136, n. 3, p. 267-277, 2001.
dc.relation.ispartofBotanical Journal of the Linnean Society
dc.subjectExtrafloral nectaries
dc.subjectFloral nectaries
dc.subjectInsect pollination
dc.subjectNectar chemical composition
dc.subjectPost-floral nectaries
dc.subjectTemporal dioecism
dc.titleNectaries and reproductive biology of croton sarcopetalus (euphorbiaceae)en