Arbuscular mycorrhizal fungi (AMF) and plant growth–promoting rhizobacteria inhabit the plant rhizosphere. Both functional groups can influence plant community structures, and interactions between them can vary from being synergistic to antagonistic. HCN‐producing Pseudomonas protegens CHA0 is a plant growth–promoting rhizobacterium. P. protegens CHA0 has been shown to weakly attach to AMF hyphae. Here, we analyze the effect of P. protegens CHA0 on the viability of intraradical AMF hyphae. Using pot experiments, we have grown mycorrhizal and nonmycorrhizal Sorghum vulgare var. M35 with P. protegens CHA0 or HCN– mutant P. protegens CHA77, which did not produce HCN. Mycorrhizal and nonmycorrhizal Sorghum grown without CHA0 or CHA77 served as the control. While metabolically active AMF was not detected in mycorrhizal plants grown with HCN+ CHA0, the percentage of root colonization of metabolically active AMF in plants grown with HCN– CHA77 was lower than in the control. Root phosphorus was highest in mycorrhizal plants grown with HCN+ CHA0, but root Fe was higher in plants grown with the bacterial strains. Our results indicate that HCN‐producing P. protegens can affect the viability of intraradical AMF.

中文翻译：

---

产 HCN 假单胞菌 CHA0 影响高粱根中不规则根瘤菌的根内活力

丛枝菌根真菌（AMF）和促进植物生长的根际细菌栖息在植物根际。两个功能组都可以影响植物群落结构，它们之间的相互作用可以从协同到拮抗不等。产 HCN 假单胞菌 CHA0 是一种促进植物生长的根际细菌。P. protegens CHA0 已被证明弱附着于 AMF 菌丝。在这里，我们分析了 P. protegens CHA0 对根内 AMF 菌丝活力的影响。使用盆栽实验，我们种植了菌根和非菌根高粱变种。M35 与 P. protegens CHA0 或 HCN– 突变体 P. protegens CHA77，不产生 HCN。在没有 CHA0 或 CHA77 的情况下生长的菌根和非菌根高粱用作对照。虽然在用 HCN+ CHA0 生长的菌根植物中未检测到具有代谢活性的 AMF，在用 HCN-CHA77 生长的植物中，代谢活性 AMF 的根部定植百分比低于对照。在用 HCN+ CHA0 生长的菌根植物中根磷最高，但在用细菌菌株生长的植物中根 Fe 更高。我们的结果表明产生 HCN 的 P. protegens 可以影响自由基内 AMF 的活力。