Bacterial ring rot of potato caused by Clavibacter sepedonicus: A successful example of defeating the enemy under international regulations

Abstract

Background Bacterial ring rot of potato (Solanum tuberosum) caused by the gram‐positive coryneform bacterium Clavibacter sepedonicus is an important quarantine disease threatening the potato industry around the globe. Since its original description in 1906 in Germany, management of ring rot has been a major problem due to the seedborne nature (via seed tubers not true seeds) of the pathogen allowing the bacterium to be transmitted long distances via infected tubers. Disease symptoms On growing potato plants: interveinal chlorosis on leaflets leading to necrotic areas and systemic wilt. On infected tubers: vascular tissues become yellowish brown with a cheesy texture due to bacterial colonization and decay. Host range Potato is the main host of the pathogen, but natural infection also occurs on eggplant, tomato, and sugar beet. Taxonomic status of the pathogen Class: Actinobacteria; Order: Actinomycetales; Family: Microbacteriaceae; Genus: Clavibacter; Species: Clavibacter sepedonicus (Spieckermann and Kotthoff 1914) Li et al. 2018. Synonyms (nonpreferred scientific names) Aplanobacter sepedonicus; Bacterium sepedonicum; Corynebacterium sepedonicum; Corynebacterium michiganense pv. sepedonicum; Clavibacter michiganensis subsp. sepedonicus. Microbiological properties Gram‐positive, club‐shaped cells with creamy to yellowish‐cream colonies for which the optimal growth temperature is 20–23°C. Distribution Asia (China, Japan, Kazakhstan, Nepal, North Korea, Pakistan, South Korea, Uzbekistan, the Asian part of Russia), Europe (Belarus, Bulgaria, Czech Republic, Estonia, Finland, Georgia, Germany, Greece, Hungary, Latvia, Lithuania, Norway, Poland, Romania, European part of Russia, Slovakia, Spain, Sweden, Turkey, Ukraine), and North America (Canada, Mexico, USA). Phytosanitary categorization CORBSE: EPPO A2 list no. 51. EU; Annex designation I/A2.

Field surveys indicate taxonomically diverse Pectobacterium species inducing soft rot of vegetables and annual crops in Iran

“…Effective diagnostic tests capable of distinguishing between target and non‐target samples are needed to support regulative rules with some degree of confidence (Pritchard et al, 2016). Trade of solanaceous vegetables/crops is under strict control in Iran especially when it comes to transportation of seed lots (Ansari et al, 2019; Khojasteh et al, 2019; Osdaghi et al, 2022; Sedighian, Krijger, et al, 2020; Sedighian, Taghavi, et al, 2020). Rapid and accurate identification of seedborne bacteria is a critical issue in terms of both storage and international trade (Cigna et al, 2017).…”

Clavibacter lycopersici sp. nov.: a peach-colored actinobacterium isolated from symptomless tomato plant

“…Plant pathogenic members of the genus, i.e. C. michiganensis, C. sepedonicus, C. insidiosus, and C. nebraskensis infecting tomato, potato, alfalfa, and maize plants, respectively, are included in the high-risk list of quarantine pathogens by the European and Mediterranean Plant Protection Organization [4,5]. Thus, they possess high economic importance, threatening solanaceous horticultural industry around the globe.…”

Symbiotic Antimicrobial Effects of Cellulose‐Based Bio‐Nanocomposite for Disease Management of Agricultural Crops

“…campestris is a Gram‐negative bacterium developing V‐shaped lesions and causing black rot disease in Brassicaceae crops [28–30] like cauliflower, broccoli, sprouts and cabbage. Clavibacter (CB) is an aerobic Gram‐positive bacterium responsible for wilt‐type diseases in tomatoes [31] and ring‐rot disease in potatoes [32] . On the other hand, P. fluorescens is a biocontrol agent which suppresses plant diseases by protecting the seeds and roots from fungal infection [33] .…”

“…Clavibacter (CB) is an aerobic Gram-positive bacterium responsible for wilt-type diseases in tomatoes [31] and ring-rot disease in potatoes. [32] On the other hand, P. fluorescens is a biocontrol agent which suppresses plant diseases by protecting the seeds and roots from fungal infection. [33] Further, the prepared nanocomposite (NC) antifungal properties were also examined against mycopathogens -Fusarium Graminearumm, and Phytophthora Spp using poison food agar assay.…”