The location of nectaries and nectar secretion in the flowers of Allium giganteum Regel

Abstract

In the flowers of <i>Allium</i> there are found septal nectaries; in particular species, their outlet can be located in different parts of the ovary. The inflorescences of these plants are a rich source of nectar for insects. The location and structure of septal nectaries in the flowers of <i>Allium giganteum</i> Regel were investigated. Light and scanning electron microscopy was used. The septal nectaries were found to be located in the lower part of the ovary and in the gynophore on which the ovary is borne. Nectar is secreted into the nectary slits from which it flows through the ducts to three openings located in the upper part of the gynophore, from whence it gets outside in the vicinity of the expanded parts of the filaments. Sugar concentration in the nectar of <i>A. giganteum</i> averaged 54.5%, while sugar weight per flower was determined to be 0.36 mg. When converted into sugar weight per inflorescence, numbering more than 2,000 flowers, it was 771.7 mg

The flower morphology in three Convallariaceae species with various attractive traits

“…Short papillae on the lower portion of filaments as well as papillose trichomes on the adaxial surface of tepals of this species have striated cuticle, resembling tepaline osmophores in other members of the order Asparagales: Asphodelus aestivus [28], Galanthus nivalis [29], and Crocus vernus [30]. Papillose osmophores with striate cuticle were also found on the ovary in some Allium species [31][32][33]. The long trichomes in the upper portion of the filaments in P. multiflorum can prevent nectar outflowing from the pendant flower, as was presumed in Asphodelus albus with erect flowers [34], or they can provide sites for secondary pollen load.…”

Pollination Biology and Environmental Water Pollution Indicator of Onion (Allium cepa L.)

“…The inflorescences A. cepa L. is of dull white colour whereas Allium aflatunense bears violet colour then slowly turned into purple colour [15]. Allium giganteum inflorescences produce red-coloured florets from the purple colour [16]. Nevertheless, the onion inflorescence displays a very strong flavour and odour due to the presence of chemical alteration of a volatile secondary metabolite like S-methyl cysteine sulphoxide compound [17].…”

Flower morphology of Allium (Amaryllidaceae) and its systematic significance

“…(2008) investigated nectary anatomy in the subgenus Melanocrommyum with molecular analysis. In addition, several studies examined nectaries in various species ( Zuraw et al., 2009 , 2010 ). Choi et al.…”