Flowering biology and structure of floral nectaries in Galanthus nivalis L.

Abstract

In Poland <em>Galanthus nivalis</em> L. is partially protected. The flowers of this species are one of the first sources of nectar and pollen for insects from February to April. The aim of this study was to present the flowering biology as well as the topography, anatomical, and ultrastructural features of the floral nectary. The flower lifespan, the breeding system, and the mass of pollen and nectar produced by the flowers were determined. Examination of the nectary structure was performed using light, fluorescence, scanning and transmission electron microscopy. The flower of <em>G. nivalis</em> lives for about 30 days. The stamens and pistils mature simultaneously and during this time nectar is secreted. The anthers of one flower produced the large amount of pollen (4 mg). The breeding system of <em>G. nivalis</em> was found to be characterized by partial self-compatibility, outcrossing, and xenogamy. The nectary is located at the top of the inferior ovary. The nectary epidermal cells are characterized by striated cuticular ornamentation. Initially, the secreted nectar formed vesicle-like protuberances under the cuticle. The epidermal and parenchymal cells contain numerous plastids, mitochondria, dictyosomes, ER cisterns, and vesicles fused with the plasmalemma, which indicates granulocrine nectar secretion.