Title: | Unravelling the structure and function of the petal appendages in the tribe Schwenckieae (Solanaceae) |
Author(s): | Paucar JOA; Isaias RMS; Stehmann JR; |
Address: | "Departamento de Botanica, Instituto de Ciencias Biologicas, Universidade Federal de Minas Gerais, Belo Horizonte, Minas Gerais, Brazil" |
ISSN/ISBN: | 1438-8677 (Electronic) 1435-8603 (Linking) |
Abstract: | "The tribe Schwenckieae (Solanaceae) is characterised by the presence of appendages on the corolla, a diagnostic trait for the group. These appendages constitute a median distal projection of the three-lobed petal and occur in the genera Melananthus and Schwenckia but are absent in Heteranthia. We investigated the micromorphology and anatomical structure of the appendages and lateral petal lobes of Schwenckia americana (two varieties), S. angustifolia, S. curviflora and S. novaveneciana, and Melananthus fasciculatus. We also performed histochemical tests to determine if the appendages are involved in the production of volatiles, acting as a fragrance secretory structure (osmophore). The appendages have a uniseriate epidermis, whose cells store phenolics and lipids. The parenchyma is starch-rich just prior to anthesis in all species studied. The sensory test and anatomical analyses identified scent-secreting tissues, not only in the appendages, but also in the lateral petal lobes, whose cells are papillose with a sculptured surface. The alpha-naphthol p-phenylenediamine (NADI) reaction detected volatile (essential oils) compounds in S. americana var. americana and S. americana var. angustifolia. We demonstrated the secretory tissues and the production of lipids in the corolla appendages of Schwenckia and Melananthus, which indicate their osmogenic function and probable scent emission to attract pollinators" |
Keywords: | *Flowers/anatomy & histology Odorants *Solanaceae/anatomy & histology/physiology Melananthus Schwenckia Floral anatomy micromorphology osmophores petal appendages secretory tissues; |
Notes: | "MedlinePaucar, J O A Isaias, R M S Stehmann, J R eng 001/Coordenacao de Aperfeicoamento de Pessoal de Nivel Superior/ APQ 306086/2017-4/Conselho Nacional de Desenvolvimento Cientifico e Tecnologico/ APQ 307011/2015-1/Conselho Nacional de Desenvolvimento Cientifico e Tecnologico/ Center for Microscopy at the Universidade Federal de Minas Gerais/ England 2019/10/24 Plant Biol (Stuttg). 2020 Mar; 22(2):146-156. doi: 10.1111/plb.13061. Epub 2019 Dec 13" |