Department of Animal Ecology & Tropical Biology, University of Würzburg, Biozentrum, Würzburg, Germany.
Plant Biol (Stuttg). 2011 Nov;13(6):918-24. doi: 10.1111/j.1438-8677.2011.00454.x. Epub 2011 Mar 3.
The epiphytic bacterial communities colonising roots and leaves have been described for many plant species. In contrast, microbiologists have rarely considered flowers of naturally growing plants. We identified bacteria isolated from the surface of petals and leaves of two plant species, Saponaria officinalis (Caryophyllaceae) and Lotus corniculatus (Fabaceae). The bacterial diversity was much lower on petals than on leaves of the same plants. Moreover, the bacterial communities differed strongly in composition: while Pseudomonadaceae and Microbacteriaceae were the most abundant families on leaves, Enterobacteriaceae dominated the floral communities. We hypothesise that antibacterial floral volatiles trigger the low diversity on petals, which is supported by agar diffusion assays using substances emitted by flowers and leaves of S. officinalis. These results suggest that bacteria should be included in the interpretation of floral traits, and possible effects of bacteria on pollination are proposed and discussed.
定殖于根和叶的附生细菌群落已被描述为许多植物物种的特征。相比之下，微生物学家很少考虑自然生长植物的花。我们从两种植物，肥皂草（石竹科）和百脉根（豆科）的花瓣和叶片表面分离出细菌。与同一植物的叶片相比，花瓣上的细菌多样性要低得多。此外，细菌群落的组成差异很大：虽然假单胞菌科和微杆菌科是叶片上最丰富的科，但肠杆菌科则主导着花区群落。我们假设抗菌花挥发物导致花瓣上的低多样性，这一点得到了使用肥皂草的花和叶散发的物质进行琼脂扩散试验的支持。这些结果表明，细菌应被纳入对花部特征的解释中，并提出和讨论了细菌对传粉的可能影响。
