Zooming-in on floral nectar: a first exploration of nectar-associated bacteria in wild plant communities
Zooming-in on floral nectar: a first exploration of nectar-associated bacteria in wild plant communities
复制标题
DOI：
10.1111/j.1574-6941.2012.01329.x
复制
发表时间：
2012-06-01
影响因子：
4.2
通讯作者：
de Vega, Clara
中科院分区：
文献类型：
--
作者：
Alvarez-Perez, Sergio;Herrera, Carlos M.;de Vega, Clara
一些动物授粉植物的花蜜通常含有高度适应的酵母菌群，这些酵母菌群可以深刻地改变花蜜的特性，因此，通过它们对昆虫觅食行为的影响，可能对植物繁殖产生重大影响。在花蜜中也偶尔观察到细菌，但它们在植物传粉者酵母系统中的流行程度、系统发育多样性和生态作用仍不清楚。在这里，我们提出了第一次报告的调查，从自然植物群落的花蜜中的细菌。从南非27种植物中采集的71份花蜜样品中分离出可培养细菌，并通过16 S rRNA基因测序进行鉴定。基于稀疏的分析被用来评估操作分类单位（OTU）丰富度在植物群落水平上使用花蜜滴作为采样单位。我们的研究结果表明，细菌是南非植物（53.5%的样品产生的增长）的花蜜的常见居民，其社区的特点是低物种丰富度（18个OTU在16 S rRNA基因序列相异截止值为3%）和适度的系统发育多样性，与大多数菌株属于γ-变形菌。此外，菌株表现出耐腐性，过氧化氢酶活性和微好氧条件下生长的能力，这三个特性可能有助于细菌克服限制其在花蜜中生存和/或生长的重要因素。
Floral nectar of some animal-pollinated plants usually harbours highly adapted yeast communities which can profoundly alter nectar characteristics and, therefore, potentially have significant impacts on plant reproduction through their effects on insect foraging behaviour. Bacteria have also been occasionally observed in floral nectar, but their prevalence, phylogenetic diversity and ecological role within plantpollinatoryeast systems remains unclear. Here we present the first reported survey of bacteria in floral nectar from a natural plant community. Culturable bacteria occurring in a total of 71 nectar samples collected from 27 South African plant species were isolated and identified by 16S rRNA gene sequencing. Rarefaction-based analyses were used to assess operational taxonomic units (OTUs) richness at the plant community level using nectar drops as sampling units. Our results showed that bacteria are common inhabitants of floral nectar of South African plants (53.5% of samples yielded growth), and their communities are characterized by low species richness (18 OTUs at a 16S rRNA gene sequence dissimilarity cut-off of 3%) and moderate phylogenetic diversity, with most isolates belonging to the Gammaproteobacteria. Furthermore, isolates showed osmotolerance, catalase activity and the ability to grow under microaerobiosis, three traits that might help bacteria to overcome important factors limiting their survival and/or growth in nectar.