Nektaria

Nektaria, commonly referred to as nectaries, are nectar-secreting glands found in many flowering plants. The term comes from Latin nectarium and is used to describe tissues that produce nectar to attract animals that assist in pollination. Nektaria can be floral, located on flowers such as petals, sepals, or reproductive organs, or extrafloral, occurring on leaves, stems, or stipules away from the floral organs.

Floral nectaries often arise from various floral tissues and can be glandular epidermis or underlying parenchyma that develop secretory ducts. Extrafloral nectaries are typically positioned on non-reproductive parts and frequently lack direct contact with the flower’s reproductive structures. The morphology of nectaries is diverse, including disc-shaped glands at the base of petals, spur or disk glands, and marginal or ring-like nectaries.

Function and chemistry are central to nectaria. They secrete a sugar-rich nectar that serves as a reward for pollinators such as bees, butterflies, hummingbirds, and other animals, thereby promoting plant reproduction. Nectar composition is mainly sugars (glucose, fructose, and sucrose) and may include amino acids, minerals, and volatile compounds that influence consumer behavior. Extrafloral nectaries, by attracting ants and other protective insects, can provide indirect plant defense against herbivores.

Nektaria are widespread across angiosperms and exhibit substantial anatomical and ecological diversity. Their study informs understanding of plant–animal interactions, pollination biology, and plant defense strategies. See also: nectary, nectar, pollination.