Department of Biological Sciences, University at Buffalo, Buffalo, New York 14260, USA.
J Exp Bot. 2010;61(1):5-9. doi: 10.1093/jxb/erp349.
Carnivorous plants inhabit nutrient-poor environments, where prominent targets of prey capture are organic nitrogen and phosphorus. Some carnivorous plants also acquire carbon from their victims. A new report focusing on Utricularia, the bladderwort, demonstrates that carbon assimilated from photosynthesis is paradoxically secreted into the trapping environment, where it may help to support a mutualistic bacterial community. This bacterial community may also secrete allelochemicals that attract microcrustaceans which bear a strong overt resemblance to bladderwort traps. Furthermore, Utricularia and its sister genus Genlisea share anomalous molecular evolutionary features, such as highly increased rates of nucleotide substitution and dynamic evolution of genome size, from approximately 60-1500 megabases depending on the species or even population. A mechanistic hypothesis, based on the mutagenic action of reactive oxygen species (ROS) is proposed to underlie these phenomena, involving error-prone repair at the level of DNA bases and double-strand breaks. It is argued that these plants are prime candidates for further research on the complexities of plant physiology associated with carnivory, metagenomic surveys of trap microbial communities, novel plant nitrogen/nutrient utilization pathways, the ecology of prey attraction, whole-plant and trap comparative development, and, finally, evolution of the minimal angiosperm genome.
食虫植物生活在营养贫瘠的环境中，其猎物的主要目标是有机氮和磷。一些食虫植物也从它们的猎物中获取碳。一项新的研究报告聚焦于狸藻类植物，表明从光合作用中同化的碳被反常地分泌到捕虫环境中，这可能有助于支持互利共生的细菌群落。这种细菌群落也可能分泌化感物质，吸引与狸藻类植物陷阱具有强烈相似性的小型甲壳类动物。此外，狸藻类植物及其姊妹属 Genlisea 具有异常的分子进化特征，例如核苷酸替换率的高度增加以及基因组大小的动态进化，具体取决于物种甚至种群，大小约为 60-1500 兆碱基。提出了一个基于活性氧（ROS）诱变作用的机制假说，来解释这些现象，包括 DNA 碱基和双链断裂水平上易错修复。有人认为，这些植物是进一步研究与食虫有关的植物生理学复杂性、陷阱微生物群落的宏基因组调查、新型植物氮/养分利用途径、猎物吸引力生态学、全株和陷阱比较发育，以及最后，最小被子植物基因组的进化的主要候选者。
