Characterization of Bacteriophages againstPseudomonas Syringaepv.Actinidiaewith Potential Use as Natural Antimicrobials in Kiwifruit Plants
Characterization of Bacteriophages againstPseudomonas Syringaepv.Actinidiaewith Potential Use as Natural Antimicrobials in Kiwifruit Plants
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DOI：
10.3390/microorganisms8070974
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发表时间：
2020-07-01
期刊：
影响因子：
4.5
通讯作者：
Bastias, Roberto
中科院分区：
文献类型：
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作者：
Flores, Oriana;Retamales, Julio;Bastias, Roberto
假单胞菌syringaepv。猕猴桃酸菌（Psa）是引起猕猴桃细菌性溃疡病的病原体，在世界范围内造成了经济损失。目前，控制这种病原体的主要策略包括使用铜基化合物甚至抗生素。然而，对这些农用化学品具有耐药性的Psa分离株的出现提高了对控制这种病原体的新替代品的需求。噬菌体已被提出作为控制农业细菌感染的替代方法，包括Psa。在这里，我们展示了13个噬菌体的分离和表征，这些噬菌体有可能控制猕猴桃植物的Psa感染。根据宿主范围和限制性片段长度多态性（RFLP）模式对噬菌体进行了鉴定。根据噬菌体对细菌的裂解作用以及对pH（4-7）、温度（4-37℃）、太阳辐射（30和60 min）等不同环境条件的耐受性选择4种噬菌体。对所选噬菌体CHF1、CHF7、CHF19和CHF21进行测序，发现与Psa phiPSA2的足噬体高度同源。猕猴桃叶片样品的体外实验表明，噬菌体混合物在施用后3小时内降低了Psa细菌负荷，并能够降低50%的损伤指数。同样，在温室条件下对猕猴桃植株进行的实验表明，这些噬菌体能够减少50%以上的Psa细菌负荷，并在30天后显著降低处理植株的损害指数。最后，所选择的噬菌体都不能感染猕猴桃植物天然微生物群中存在的其他细菌。这些结果表明，噬菌体是控制猕猴桃植物Psa感染的一种有吸引力的替代方法。
Pseudomonas syringaepv.actinidiae(Psa) is the causal agent of a bacterial canker in kiwifruit plants and has caused economic losses worldwide. Currently, the primary strategies to control this pathogen include the use of copper-based compounds and even antibiotics. However, the emergence of isolates of Psa that are resistant to these agrochemicals has raised the need for new alternatives to control this pathogen. Bacteriophages have been proposed as an alternative to control bacterial infections in agriculture, including Psa. Here, we show the isolation and characterization of 13 phages with the potential to control Psa infections in kiwifruit plants. The phages were characterized according to their host range and restriction fragment length polymorphism (RFLP) pattern. Four phages were selected according to their lytic effect on the bacteria and their tolerance to different environmental conditions of pH (4-7), temperature (4-37 degrees C), and solar radiation exposure (30 and 60 min). The selected phages (CHF1, CHF7, CHF19, and CHF21) were sequenced, revealing a high identity with the podophage of Psa phiPSA2. In vitro assays with kiwifruit leaf samples demonstrated that the mixture of phages reduced the Psa bacterial load within three hours post-application and was able to reduce the damage index in 50% of cases. Similarly, assays with kiwifruit plants maintained in greenhouse conditions showed that these phages were able to reduce the Psa bacterial load in more than 50% of cases and produced a significant decrease in the damage index of treated plants after 30 days. Finally, none of the selected phages were able to infect the other bacteria present in the natural microbiota of kiwifruit plants. These results show that bacteriophages are an attractive alternative to control Psa infections in kiwifruit plants.