Departamento de Biologia, Faculdade de Filosofia, Ciências e Letras, Universidade de São Paulo, Ribeirão Preto, Brazil.
Departamento de Ecologia, Instituto de Biociências, Universidade de São Paulo, São Paulo, Brazil.
Plant Biol (Stuttg). 2021 Mar;23(2):259-266. doi: 10.1111/plb.13221. Epub 2020 Dec 31.
Oncidiinae is one of the most important subtribes among the Neotropical orchids, with an enormous diversity of floral morphology and secretory structures. This subtribe attracts a diverse array of pollinators which explore a variety of floral resources of its flowers. In this paper we provide a detailed investigation of the floral anatomy of 32 species of micro Oncidiinae. We applied histochemical tests in order to determine the diversity of the glands and rewards. The diversity of secretory flower structures and rewards was related to the group of pollinators known for this subtribe. We verified that half of the species (16 species, 50%) secrete oil as a resource, being pollinated by female of solitary bees. Species of some distinct nectar-secreting genera (four species, 12.5%) are pollinated by a range of nectar-searching animals. Species of the genus Notylia (four species, 12.5%) release floral perfumes that reward male Euglossini bees. Most of the investigated species (six species, 18.75%) possess osmophores that are involved in pollinator attraction. Two species of Capanemia (6.25%) do not offer any floral reward, suggesting that pollination by food deception is involved. There are strong variations in the anatomy of reward-producing structures and resources in Oncidiinae. The diversity of floral rewards affects the range of pollinators, which are related to the diversification of this subtribe throughout the Neotropics. The understanding of relationships between Oncidiinae species and their pollinators is crucial to our knowledge of the evolution of pollination systems in this huge plant family represented by the orchids.
兰屿鸟巢兰亚族是新热带地区兰花中最重要的亚族之一，其花朵具有多样的形态和分泌结构。该亚族吸引了各种各样的传粉者，它们探索着花朵多样化的花部资源。本文详细研究了 32 种微型兰屿鸟巢兰的花部解剖结构。我们应用组织化学测试来确定腺体和蜜源的多样性。分泌结构和蜜源的多样性与该亚族已知的传粉者群体有关。我们发现，一半的物种（16 种，50%）分泌油脂作为资源，由独居雌蜂授粉。一些具有明显花蜜分泌属（4 种，12.5%）的物种由一系列花蜜搜索动物授粉。Notylia 属（4 种，12.5%）的物种释放花的香味，以奖励雄性 Euglossini 蜜蜂。大多数研究物种（6 种，18.75%）具有吸引传粉者的香体。两种 Capanemia 属（6.25%）的物种不提供任何花部蜜源，表明涉及食性欺骗的传粉。兰屿鸟巢兰亚族的蜜源产生结构和资源在解剖学上存在强烈的变异。蜜源的多样性影响传粉者的范围，这与该亚族在新热带地区的多样化有关。了解兰屿鸟巢兰属物种与其传粉者之间的关系对于我们了解以兰花为代表的这个庞大植物科的授粉系统进化至关重要。
