Department of Entomology and Plant Pathology, Auburn University, Auburn, AL 36849.
Plant Dis. 2018 Jan;102(1):67-72. doi: 10.1094/PDIS-04-17-0478-RE. Epub 2017 Oct 23.
Several studies have shown that mixtures of plant-growth-promoting rhizobacteria (PGPR) could enhance biological control activity for multiple plant diseases through the mechanisms of induced systemic resistance or antagonism. Prior experiments showed that four individual PGPR strains-AP69 (Bacillus altitudinis), AP197 (B. velezensis), AP199 (B. velezensis), and AP298 (B. velezensis)-had broad-spectrum biocontrol activity via antagonism in growth chambers against two foliar bacterial pathogens (Xanthomonas axonopodis pv. vesicatoria and Pseudomonas syringae pv. tomato) and one of two tested soilborne fungal pathogens (Rhizoctonia solani and Pythium ultimum). Based on these findings, the overall hypothesis of this study was that a mixture of two individual PGPR strains would exhibit better overall biocontrol and plant-growth promotion than the individual PGPR strains. Two separate greenhouse experiments were conducted. In each experiment, two individual PGPR strains and their mixtures were tested for biological control of three different diseases and for plant-growth promotion in the presence of the pathogens. The results demonstrated that the two individual PGPR strains and their mixtures exhibited both biological control of multiple plant diseases and plant-growth promotion. Overall, the levels of disease suppression and growth promotion were greater with mixtures than with individual PGPR strains.
几项研究表明，植物生长促进根际细菌（PGPR）的混合物可以通过诱导系统抗性或拮抗作用来增强对多种植物病害的生物防治活性。先前的实验表明，四种单独的 PGPR 菌株-AP69（高山芽孢杆菌）、AP197（贝莱斯芽孢杆菌）、AP199（贝莱斯芽孢杆菌）和 AP298（贝莱斯芽孢杆菌）-通过在生长室中对两种叶部细菌性病原体（辣椒疮痂病和番茄丁香假单胞菌）和两种测试的土传真菌病原体之一（立枯丝核菌和终极腐霉）的拮抗作用具有广谱生物防治活性。基于这些发现，本研究的总体假设是，两种单独的 PGPR 菌株的混合物将比单独的 PGPR 菌株表现出更好的整体生物防治和植物生长促进作用。进行了两项单独的温室实验。在每个实验中，测试了两种单独的 PGPR 菌株及其混合物对三种不同疾病的生物防治和在病原体存在下的植物生长促进作用。结果表明，两种单独的 PGPR 菌株及其混合物均表现出对多种植物病害的生物防治和植物生长促进作用。总体而言，与单独的 PGPR 菌株相比，混合物的疾病抑制和生长促进水平更高。
