Ryniewicz Justyna, Skłodowski Mateusz, Chmur Magdalena, Bajguz Andrzej, Roguz Katarzyna, Roguz Agata, Zych Marcin
Botanic Garden, Faculty of Biology, University of Warsaw, 00-478 Warsaw, Poland.
Department of Biology and Ecology of Plants, Faculty of Biology, University of Bialystok, 15-245 Bialystok, Poland.
Plants (Basel). 2020 Oct 1;9(10):1297. doi: 10.3390/plants9101297.
Floral nectar, being a primary reward for insect visitors, is a key factor in shaping plant-pollinator interactions. However, little is known about the variability in nectar traits, which could potentially affect pollinators and the reproduction of the species. We investigated intraspecific variation in nectar traits in 14 populations of a Red-listed plant. Populations varied in terms of the proportion of self-compatible and self-incompatible individuals, and insect communities visiting flowers. Using HPLC, we determined the nectar sugar and amino acid (AA) composition and concentration. We also recorded some basic habitat parameters, which could influence nectar chemistry. In seven selected populations, we investigated the taxonomic composition of the insects visiting flowers. Our observations revealed significant intraspecific variability in nectar chemistry in . Nectar production was male-biased, with male-phase flowers secreting sucrose- and AA-rich nectar. An analysis revealed that variability in nectar may be slightly shaped by environmental factors. The studied nectar characters, especially sugars, had little effect on insects visiting flowers. We argue that variation in nectar traits in this generalist plant is a matter of random genetic drift or "adaptive wandering" rather than directional specialization and adaptation in the most effective and abundant group of pollinators.
花蜜作为对访花昆虫的主要回报，是塑造植物 - 传粉者相互作用的关键因素。然而，对于花蜜性状的变异性了解甚少，而这种变异性可能会影响传粉者和物种的繁殖。我们调查了一种濒危植物14个种群的花蜜性状种内变异。种群在自交亲和与自交不亲和个体的比例以及访花昆虫群落方面存在差异。我们使用高效液相色谱法测定了花蜜的糖和氨基酸（AA）组成及浓度。我们还记录了一些可能影响花蜜化学组成的基本栖息地参数。在七个选定的种群中，我们调查了访花昆虫的分类组成。我们的观察结果显示，[原文此处可能缺失具体种群信息]花蜜化学存在显著的种内变异性。花蜜分泌偏向雄性，雄花期花朵分泌富含蔗糖和氨基酸的花蜜。一项分析表明，花蜜的变异性可能受到环境因素的轻微影响。所研究的花蜜特征，尤其是糖类，对访花昆虫影响很小。我们认为，这种广布植物花蜜性状的变异是随机遗传漂变或“适应性漫游”的结果，而非针对最有效且数量最多的传粉者群体进行定向特化和适应。
