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Flower Parts Floral nectaries Floral nectaries are glands formed within the flower that exude a food reward to entice pollinators to visit and probe the flower. Banana (Musa) with nectar dripping from the female flower. Back to main flower menu Next Back to flower parts menu Main menu Flower Parts Floral nectaries Floral nectaries are typically found at the base of the flower and can be formed on ovary tissue, petals, stamens or as a disc from the top of the receptacle. Nectar gland Back to main flower menu Back Next Back to flower parts menu Main menu Flower Parts Floral nectaries The nectaries at the base of flowers with floral tubes force the pollinator to push past the anthers and stigma on its way to the nectar reward. Longitudinal section through the flower. Stamens Stigma Nectar disk Ovary Sepals Back to main flower menu Back Next Corolla tube Juanulloa mexicana Back to flower parts menu Main menu Flower Parts Floral nectaries Echeveria produces a short tubular flower with nectar glands alternating with the stamens at the base of the ovary. Flower with petals removed. Flower longitudinal section Stamens Ovaries Nectar glands Back to main flower menu Back Next Back to flower parts menu Main menu Flower Parts Floral nectaries Flowering tobacco (Nicotiana) is a typical tubular flower with floral nectaries on the sides of the ovary. Stigma Floral tube Stamens Ovary Style Nectar glands Back to main flower menu Back Next Back to flower parts menu Main menu Flower Parts Floral nectaries – Nectar disk In some species, the nectaries are joined into a nectar disk or ring that forms at the top of the receptacle and surrounds the ovary. Stigma Style Nectar disk Stamens Flower with petals and stamens, style and stigma removed. Receptacle tissue Petals Back to main flower menu Sweet potato vine (Ipomoea) Back Next Nectar disk Back to flower parts menu Ovary Main menu Flower Parts Floral nectaries – Nectar disk Sweet gum produces separate male and female flowers. There is a receptacle disk where the nectaries are formed. Male flowers Female flowers Stigma Nectar Stamens Petals Corolla tube Receptacle nectar disk Petals Sweet gum (Nyssa) Back to main flower menu Back Next Back to flower parts menu Main menu Flower Parts Floral nectaries - Petals In Christmas rose (Helleborus), the sepals assume the showy role usually performed by the petals. The petals are reduced and modified into a basal ring of nectaries to attract pollinators. Stamens Sepals Stamens Modified petals with nectar glands Back to main flower menu Back Next Back to flower parts menu Main menu Flower Parts Floral nectaries – Petal-like Similar petal-modified organs with nectar glands are produced in black cumin (Nigella sativa). These structures are sometimes called nectar or honey leaves even though they are petal-derived. Stamens Sepals Nectar glands Nectar “leaves” Back to main flower menu Back Next Back to flower parts menu Main menu Flower Parts Floral nectaries – Petal-like Some Euphorbia pulcherrima) species produce nectar glands on colored, petal-like appendages often bordering the edge of a cyanthium. The color of the petal-like nectar appendage may be involved in attracting pollinators. Euphorbia amygdaloides Nectar glands Petal-like appendage Ovary Stigma and style Back to main flower menu Euphorbia myrsinites Back Next Back to flower parts menu Main menu Flower Parts Floral nectaries - Cyathia Poinsettia (Euphorbia pulcherrima) also produces cyathia, but it produces a single large nectar gland along the side of the inflorescence. A cyathium consists of multiple male flowers each reduced to a single stamen and a single female flower grouped together into an inflorescence that resembles a single flower. Cyathium Ovary Staminate flowers Nectar gland Bracts Back to main flower menu Back Next Back to flower parts menu Main menu Flower Parts Floral nectaries - Corona Several Hoya species have floral nectaries on the tips of the corona tissue. White petals Brown corona Nectar glands The corona is a tissue usually derived from the petals that forms between the petal (corolla) whorl and the stamen whorl in the flower. Hoya Back to main flower menu Back Next Back to flower parts menu Main menu Flower Parts Floral nectaries - Stamens Pansy (Viola) has five stamens with fused bases that surround the ovary. From two of the stamens, a long nectary is produced and the pair of horned nectaries grow down into the petal spur. Stamen nectaries are not common. Stigma and style Stigma and style Stamens Ovary Stamens Stamens Petal spur Pansy (Viola) Back to main flower menu Stamen nectary Back Next Back to flower parts menu Stamen nectary Main menu Flower Parts Floral nectaries - Extrafloral nectaries Nectaries can form on other tissue besides floral tissue. These are termed extrafloral nectaries. Since these nectaries on trumpet flower occur on the sepals that are outside the interior of the flower, they function as extrafloral nectaries even though they are technically on a part of the flower. Petals (corolla tube) Sepals Nectar glands Trumpet flower (Campsis) Back to main flower menu Back Back to flower parts menu Main menu
