核桃树在世界范围内被种植和开发用于商业木材和坚果生产。它们是异形移植的植物,选择在不同土壤类型和条件下生长的砧木,并提供最佳的锚固,活力,以及对土传病虫害的抗性或耐受性。然而,没有一个砧木能容忍所有影响核桃生产的因素。在欧洲,核桃属主要用作砧木。像大多数陆地植物一样,核桃树形成丛枝菌根共生,改善水和养分吸收并提供额外的生态系统服务。丛枝菌根共生对根系基因调控的影响,然而,从未被评估过。我们分析了J.regia的一种砧木对丛枝菌根真菌不规则根瘤菌DAOM197198定殖的反应。与未定殖植物相比,菌根植物的植物生长以及根和芽中的氮和磷浓度显着增加。此外,我们已经表明1,549个基因差异表达,832和717个基因上调和下调,分别。分析还揭示了一些砧木基因通过菌根途径参与植物营养,与其他菌根木本物种相似:葡萄和毛果杨。此外,对GO和KEGG途径进行的富集分析揭示了一些特定于J.regia的调控(即,juglone途径)。该分析加强了丛枝菌根共生在根基因调控中的作用,并且需要深入研究多种丛枝菌根真菌对根基因调控的影响,而且接穗对核桃树等异株植物中丛枝菌根真菌的功能也有影响。
Walnut trees are cultivated and exploited worldwide for commercial timber and nut production. They are heterografted plants, with the rootstock selected to grow in different soil types and conditions and to provide the best anchorage, vigor, and resistance or tolerance to soil borne pests and diseases. However, no individual rootstock is tolerant of all factors that impact walnut production. In Europe, Juglans regia is mainly used as a rootstock. Like most terrestrial plants, walnut trees form arbuscular mycorrhizal symbioses, improving water and nutrient uptake and providing additional ecosystem services. Effects of arbuscular mycorrhizal symbiosis on root gene regulation, however, has never been assessed. We analyzed the response of one rootstock of J. regia to colonization by the arbuscular mycorrhizal fungus Rhizophagus irregularis DAOM197198. Plant growth as well as the nitrogen and phosphorus concentrations in roots and shoots were significantly increased in mycorrhizal plants versus non-colonized plants. In addition, we have shown that 1,549 genes were differentially expressed, with 832 and 717 genes up- and down-regulated, respectively. The analysis also revealed that some rootstock genes involved in plant nutrition through the mycorrhizal pathway, are regulated similarly as in other mycorrhizal woody species: Vitis vinifera and Populus trichocarpa. In addition, an enrichment analysis performed on GO and KEGG pathways revealed some regulation specific to J. regia (i.e., the juglone pathway). This analysis reinforces the role of arbuscular mycorrhizal symbiosis on root gene regulation and on the need to finely study the effects of diverse arbuscular mycorrhizal fungi on root gene regulation, but also of the scion on the functioning of an arbuscular mycorrhizal fungus in heterografted plants such as walnut tree.