Genetics, Faculty of Biology, University of Munich (LMU), Martinsried-München, Germany.
Curr Opin Plant Biol. 2009 Aug;12(4):491-9. doi: 10.1016/j.pbi.2009.05.010. Epub 2009 Jul 23.
The mechanisms by which legumes choose their rhizobial partners operate independently from their ability to fix nitrogen. As a result of this naivety, symbiotic nitrogen fixation is often suboptimal. The initial recognition of the bacterial partner and the subsequent signal transduction in the host root utilises components that are functionally conserved between legumes and probably actinorhiza host plants. However, the later steps, which largely determine symbiotic performance, are subject to ongoing evolutionary diversification of molecular mechanisms. For example, the impact of bacterial effector proteins, the occurrence of terminal bacteroid differentiation and the expression of bacterial hydrogenase, all depend on the plant genotype. Strategies towards increased nitrogen fixation of legumes in agriculture need to encompass this diversification of mechanisms.
豆科植物选择根瘤菌伙伴的机制与其固氮能力是独立运作的。由于这种天真，共生固氮往往不是最佳的。细菌伙伴的最初识别和随后在宿主根中的信号转导利用了豆科植物和放线菌宿主植物之间功能保守的成分。然而，决定共生性能的后期步骤，受到分子机制的持续进化多样化的影响。例如，细菌效应蛋白的影响、终端类菌体分化的发生和细菌氢化酶的表达，都取决于植物基因型。在农业中提高豆科植物固氮能力的策略需要包含这种机制的多样化。
