Magagula Phinda, Taylor Nicky, Swart Velushka, van den Berg Noëlani
Forestry and Agricultural Biotechnology Institute, University of Pretoria, Hatfield 0002, South Africa.
Department of Plant and Soil Sciences, University of Pretoria, Hatfield 0002, South Africa.
Plant Dis. 2021 Nov;105(11):3385-3396. doi: 10.1094/PDIS-08-20-1751-RE. Epub 2021 Nov 7.
is the causal agent of white root rot (WRR), a fatal disease affecting many woody plants, including avocado (). As with other root diseases, an integrated approach is required to control WRR. No fully effective control methods are available, and no chemical or biological agents against have been registered for use on avocado in South Africa. Fluazinam has shown promising results in the greenhouse and field in other countries, including Spain. The current study aimed to investigate the potential of a fumigant, chloropicrin, and biological control agents (B-Rus, Beta-Bak, Mity-Gro, and ) against both in vitro and in vivo as compared with fluazinam. In a greenhouse trial, results showed that and B-Rus were as effective as fluazinam at inhibiting in vitro and suppressed WRR symptoms when applied before inoculation with . In contrast, Mity-Gro and Beta-Bak failed to inhibit the pathogen in vitro and in the greenhouse trial, despite application of the products to plants before infection. Fluazinam suppressed WRR symptoms in plants when applied at the early stages of infection, whereas chloropicrin rendered the pathogen nonviable when used as a preplant treatment. Plants treated with , B-Rus, and fluazinam sustained dry mass production and net CO assimilation by maintaining the green leaf tissues despite being infected with the pathogen. This study has important implications for the integrated management of WRR.
是白根腐病（WRR）的致病因子，白根腐病是一种影响包括鳄梨在内的许多木本植物的致命疾病。与其他根部疾病一样，需要采用综合方法来控制白根腐病。目前没有完全有效的控制方法，在南非也没有针对 在鳄梨上使用的化学或生物制剂注册。在包括西班牙在内的其他国家，氟唑菌酰胺在温室和田间试验中已显示出有前景的结果。本研究旨在调查熏蒸剂氯化苦和生物防治剂（B-Rus、Beta-Bak、Mity-Gro和 ）与氟唑菌酰胺相比，在体外和体内对 的防治潜力。在温室试验中，结果表明， 在体外抑制 方面与氟唑菌酰胺效果相当，并且在接种 之前施用时可抑制白根腐病症状。相比之下，尽管在 感染前将Mity-Gro和Beta-Bak施用于植物，但它们在体外和温室试验中均未能抑制病原菌。在感染早期施用氟唑菌酰胺可抑制植物中的白根腐病症状，而氯化苦在用作种植前处理时可使病原菌失去活力。用 、B-Rus和氟唑菌酰胺处理的植物尽管感染了病原菌，但通过维持绿叶组织维持了干物质生产和净二氧化碳同化。本研究对白根腐病的综合管理具有重要意义。
