Auxin secretion by Bacillus amyloliquefaciens FZB42 both stimulates root exudation and limits phosphorus uptake in Triticum aestivium.
Auxin secretion by Bacillus amyloliquefaciens FZB42 both stimulates root exudation and limits phosphorus uptake in Triticum aestivium.
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DOI：
10.1186/1471-2229-14-51
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发表时间：
2014-02-21
影响因子：
5.3
通讯作者：
Jones DL
中科院分区：
文献类型：
--
作者：
Talboys PJ;Owen DW;Healey JR;Withers PJ;Jones DL
利用产生生长素的根际细菌作为农产品有望增加根系产量，从而增加磷酸盐（Pi）的吸收。虽然这些细菌在体外促进根的产生，但细菌-植物在活土中相互作用的性质，特别是对养分吸收的影响，尚不清楚。本研究以解淀粉芽孢杆菌FZB42作为生长素根瘤菌对小麦种子进行处理。然后研究了对根系生产、Pi吸收、Pi相关基因表达和有机碳(C)渗出的影响。解淀粉芽孢杆菌FZB42种子处理在低环境Pi浓度下增加了根系产量，但显著抑制了根系对Pi的吸收。这与生长素介导的Pi转运体TaPHT1.8和TaPHT1.10的表达减少相吻合。外源生长素的施用也引起根C分泌量的增加。在较高的外源浓度下，解淀粉芽孢杆菌FZB42促进了根的生长，但对Pi的吸收不受影响。我们得出结论，解淀粉芽孢杆菌FZB42在促进根生成的同时，生长素的生物合成也重塑了Pi转运蛋白的表达，并增加了有机C的分泌。这表明根细菌衍生的生长素在根表面定植后的潜在重要性，以及这种细菌-植物在土壤中相互作用的性质。
The use of auxin-producing rhizosphere bacteria as agricultural products promises increased root production and therefore greater phosphate (Pi) uptake. Whilst such bacteria promote root production in vitro, the nature of the bacteria-plant interaction in live soil, particularly concerning any effects on nutrient uptake, are not known. This study uses Bacillus amyloliquefaciens FZB42, an auxin-producing rhizobacterium, as a dressing on Triticum aestivum seeds. It then examines the effects on root production, Pi uptake, Pi-related gene expression and organic carbon (C) exudation. Seed treatment with B. amyloliquefaciens FZB42 increased root production at low environmental Pi concentrations, but significantly repressed root Pi uptake. This coincided with an auxin-mediated reduction in expression of the Pi transporters TaPHT1.8 and TaPHT1.10. Applied exogenous auxin also triggered an increase in root C exudation. At high external Pi concentrations, root production was promoted by B. amyloliquefaciens FZB42, but Pi uptake was unaffected. We conclude that, alongside promoting root production, auxin biosynthesis by B. amyloliquefaciens FZB42 both re-models Pi transporter expression and elevates organic C exudation. This shows the potential importance of rhizobacterial-derived auxin following colonisation of root surfaces, and the nature of this bacteria-plant interaction in soil.