Biological control of plant diseases with antagonistic bacteria is a promising alternative to conventional chemical control strategies. In vitro screening for inhibition of mycelial growth of phytopathogenic fungi by bacterial isolates is the first step in selecting putative bacterial biocontrol agents. Dual culture plate assay is the most common method involved in this first-line selection process. However, it needs independent agar plates to test antagonism by a specific bacterial isolate against each of the fungal phytopathogen. Two modified in vitro antagonism tests are proposed here. Antagonistic activity of a putative biocontrol bacterial strain against four different fungal phytopathogens could be assessed in a single agar plate simultaneously. A comparison of the new methods with conventional dual culture plate assay was also done. The proposed methods are easy to perform and results of antagonism are obtained rapidly. Results of fungal inhibition were qualitatively comparable with that generated through dual culture plate assay. Quantity of resources such as agar medium and plates required for the modified antagonistic assays is several folds less than that required for dual culture plate assay.

中文翻译：

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用于体外评估细菌生防分离株对多种真菌植物病原体的拮抗作用的新型快速琼脂平板方法

用拮抗细菌生物防治植物病害是传统化学防治策略的一种有前景的替代方法。体外筛选细菌分离物抑制植物病原真菌菌丝生长是选择假定的细菌生物防治剂的第一步。双培养板检测是这一一线选择过程中最常用的方法。然而，它需要独立的琼脂平板来测试特定细菌分离物对每种真菌植物病原体的拮抗作用。两种体外修饰此处建议进行拮抗试验。可以在单个琼脂平板中同时评估推定的生物防治细菌菌株对四种不同真菌植物病原体的拮抗活性。还进行了新方法与传统双培养板测定的比较。所提出的方法易于执行并且可以快速获得拮抗作用的结果。真菌抑制的结果与通过双培养板测定产生的结果具有定性可比性。改良拮抗试验所需的琼脂培养基和平板等资源的数量比双培养板试验所需的资源少几倍。