Recent studies showed that bacterial volatile organic compounds (VOCs) play an important role in the suppression of phytopathogens. The ability of VOCs produced by avocado (Persea americana Mill.) rhizobacteria to suppress the growth of common avocado pathogens was therefore investigated. We evaluated the antifungal activity of VOCs emitted by avocado rhizobacteria in a first screening against Fusarium solani, and in subsequent antagonism assays against Fusarium sp. associated with Kuroshio shot hole borer, Colletotrichum gloeosporioides and Phytophthora cinnamomi, responsible for Fusarium dieback, anthracnosis and Phytophthora root rot in avocado, respectively. We also analyzed the composition of the bacterial volatile profiles by solid phase microextraction (SPME) gas chromatography coupled to mass spectrometry (GC–MS). Seven isolates, belonging to the bacterial genera Bacillus and Pseudomonas, reduced the mycelial growth of F. solani with inhibition percentages higher than 20%. Isolate HA, related to Bacillus amyloliquefaciens, significantly reduced the mycelial growth of Fusarium sp. and C. gloeosporioides and the mycelium density of P. cinnamomi. Isolates SO and SJJ, also members of the genus Bacillus, reduced Fusarium sp. mycelial growth and induced morphological alterations of fungal hyphae whilst isolate HB, close to B. mycoides, inhibited C. gloeosporioides. The analysis of the volatile profiles revealed the presence of ketones, pyrazines and sulfur-containing compounds, previously reported with antifungal activity. Altogether, our results support the potential of avocado rhizobacteria to act as biocontrol agents of avocado fungal pathogens and emphasize the importance of Bacillus spp. for the control of emerging avocado diseases such as Fusarium dieback.

最近的研究表明，细菌挥发性有机化合物（VOC）在抑制植物病原体中起着重要作用。因此，研究了鳄梨（Persea americana Mill。）根瘤菌产生的VOC抑制常见鳄梨病原体生长的能力。我们在首次对茄镰刀菌的筛选以及随后对镰刀菌属的拮抗试验中，评估了鳄梨根瘤菌释放的VOC的抗真菌活性。与黑潮枪hole，炭疽菌和疫霉菌有关，分别导致鳄梨枯萎病，炭疽病和疫霉根腐病。我们还通过固相微萃取（SPME）气相色谱-质谱联用技术（GC-MS）分析了细菌挥发性成分的组成。属于细菌芽孢杆菌属和假单胞菌属的七个分离株降低了茄形镰刀菌的菌丝生长，其抑制百分数高于20％。与解淀粉芽孢杆菌相关的分离株HA显着降低了镰刀菌的菌丝体生长。和C. gloeosporioides和菌丝体密度肉桂。隔离SO和SJJ，也是属芽孢杆菌，减少镰刀菌。菌丝生长和真菌菌丝的诱导形态变化，同时分离HB，接近B. mycoides，抑制了C. gloeosporioides。挥发性物质的分析表明，以前报道过具有抗真菌活性的酮，吡嗪和含硫化合物的存在。总之，我们的结果支持鳄梨根瘤菌作为鳄梨真菌病原体生物防治剂的潜力，并强调了芽孢杆菌的重要性。用于控制鳄梨病等新出现的鳄梨病。