Abstract Detail

Developmental and Structural Section

Matsunaga, Kelly K.S. [1], Mesler, Michael R. [2], Tomescu, Alexandru [1].

Nectary Structure of Scoliopus bigelovii (Liliaceae).

Scoliopus bigelovii (slinkpod, fetid-adder's tongue) is a member of the Liliaceae native to California's redwood forests, whose ill-scented flowers are self-incompatible and pollinated by fungus gnats. Although a handful of papers document various anatomical features, no detailed description of nectary structure exists. The perigonal nectaries of S. bigelovii are located in a median groove on the proximal portion of the sepals and do not visibly produce nectar, although foraging behavior of pollinators suggests that nectar is provided. In this study the presence of nectar was confirmed, and the anatomy of the nectary region was described using light and scanning electron microscopy. The nectaries consist of a band of parallel ridges of nectariferous tissue that extends from near the base of the sepal to just beyond where the sepals recurve. The nectariferous tissue is composed of a uniseriate, secretory epidermis overlying one to four layers of nectary parenchyma. Nectariferous cells were identified by their relatively small size and conspicuously dense cytoplasm containing small vacuoles. Although this tissue lacks its own vasculature, the nectary appears to be supplied by the main sepal bundles through a band of large, tightly packed subglandular parenchyma cells, in which the bundles are embedded. SEM reveals abundant protoplasmic material in cells of the subglandular and nectariferous tissues, with greatest density in the epidermis during anthesis. Considerably less material was observed in the mesophyll abaxial and lateral to the nectary region. A very thin cuticle lines the nectary, and we infer that the small volume of nectar produced permeates this cuticle without rupturing it. Moreover, the lack of both specialized vasculature and visible nectar, hallmarks of nectar-secreting tissues when present, can be explained by the small quantity of nectar produced and ultimately required for rewarding pollinators. Nevertheless, the position of the nectary remains consistent with other Liliaceae, and these findings contribute to our knowledge of the anatomical diversity of nectaries within the family.

Broader Impacts:

1 - Humboldt State University, Department of Biological Sciences, 1 Harpst Street, Arcata, CA, 95521, USA
2 - Humboldt State University, Department of Biological Sciences, 1 Harpst St., Arcata, CA, 95521, USA

Keywords:
Scoliopus
nectary
pollination
Liliaceae
sepal
fungus gnat.

Presentation Type: Oral Paper:Papers for Sections
Session: 16
Location: Lindell A/Chase Park Plaza
Date: Monday, July 11th, 2011
Time: 2:30 PM
Number: 16005
Abstract ID:409