Abstract：
Soft rot Pectobacteriaceae (SRP) are a group of destructive Gram-negative phytopathogens that can infect a wide range of plant hosts, including potatoes. There are no effective control agents available against SRP, making their management challenging. We have developed a novel approach to protect potato tubers against SRP. It makes use of encapsulated predatory Bdellovibrio bacteriovorus bacteria that upon release from a polymeric carrier, prey upon SRP. We applied a carrageenan-trehalose-based formulation containing a B. bacteriovorus HD100 predator to prevent soft-rot disease development in potato tubers, under various conditions. The dried formulation exhibited very high stability over an eighteen-month period at room temperature (˜25ºC), in contrast to unencapsulated suspensions of the predator, in which viability decreased rapidly below detection level. The rehydrated formulation was as efficient as freshly grown unencapsulated predators, and provided high protection in potted potato tubers, displaying an average of 50% reduction in disease parameters (e.g. tissue decay and disease index) under controlled conditions at 7-days post-inoculation and planting. The protective effect provided by this formulation was maintained in longer-term trials (28 days) conducted in larger vessels within a net-house under natural climate conditions, highlighting its potential for practical application in the field.
摘要：
软腐烂杆菌（SRP）是一组破坏性的革兰氏阴性植物病原体，可以感染多种植物宿主，包括土豆。没有针对SRP的有效控制剂，使他们的管理具有挑战性。我们开发了一种新的方法来保护马铃薯块茎免受SRP的侵害。它利用封装的捕食性Bdellovibrio细菌从聚合物载体释放后，捕食SRP。我们应用了一种基于角叉菜胶-海藻糖的配方，其中含有B.bacteriovorusHD100捕食者，以防止马铃薯块茎中的软腐病发展。在各种条件下。干燥的制剂在室温（约25ºC）下经过18个月的时间表现出非常高的稳定性，与未包裹的捕食者悬浮液相反，其中生存力迅速下降，低于检测水平。复水配方与新鲜生长的未包封的捕食者一样有效，并在盆栽马铃薯块茎中提供高度保护，在接种和种植后7天，在受控条件下显示疾病参数（例如组织腐烂和疾病指数）平均减少50％。该制剂提供的保护作用在自然气候条件下在网房内的较大容器中进行的长期试验(28天)中保持不变。突出了其在该领域的实际应用潜力。
