Red de Estudios Moleculares Avanzados, Instituto de Ecología, A.C. Carretera antigua a Coatepec 351, Col. El Haya, 91070, Xalapa, Veracruz, Mexico; Instituto de Agroindustrias, Universidad Tecnológica de la Mixteca, Carretera a Acatlima Km. 2.5, Acatlima, 69000, Huajuapan de León, Oaxaca, Mexico.
Red de Estudios Moleculares Avanzados, Instituto de Ecología, A.C. Carretera antigua a Coatepec 351, Col. El Haya, 91070, Xalapa, Veracruz, Mexico.
Microbiol Res. 2019 Feb;219:74-83. doi: 10.1016/j.micres.2018.11.009. Epub 2018 Nov 24.
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（VOCs）在抑制植物病原菌方面发挥着重要作用。因此，研究了鳄梨（Persea americana Mill.）根际细菌产生的 VOC 抑制常见鳄梨病原菌生长的能力。我们首先评估了鳄梨根际细菌产生的 VOC 对尖孢镰刀菌的抗真菌活性，然后在后续的拮抗试验中对抗与黑潮穿孔虫相关的镰刀菌、胶孢炭疽菌和疫霉属，它们分别负责鳄梨的镰刀菌枯萎病、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（GC-MS）分析了细菌挥发性图谱的组成。属于芽孢杆菌属和假单胞菌属的七个分离物降低了尖孢镰刀菌的菌丝生长，抑制率高于 20%。与解淀粉芽孢杆菌相关的分离物 HA 显著降低了镰刀菌和胶孢炭疽菌的菌丝生长以及疫霉菌丝密度。芽孢杆菌属的分离物 SO 和 SJJ 也降低了镰刀菌的菌丝生长，并诱导真菌菌丝的形态改变，而与枯草芽孢杆菌密切相关的分离物 HB 则抑制了胶孢炭疽菌。挥发性图谱的分析表明存在具有抗真菌活性的酮类、吡嗪类和含硫化合物。总之，我们的研究结果支持鳄梨根际细菌作为鳄梨真菌病原体生物防治剂的潜力，并强调了芽孢杆菌属在控制新兴鳄梨疾病（如镰刀菌枯萎病）方面的重要性。
