Cercospora beticola
| Cercospora beticola | |
|---|---|
 | |
| Cercospora beticola on sugarbeets | |
| Scientific classification | |
| Kingdom: | Fungi |
| Phylum: | Ascomycota |
| Class: | Dothideomycetes |
| Subclass: | Dothideomycetidae |
| Order: | Capnodiales |
| Family: | Mycosphaerellaceae |
| Genus: | Cercospora |
| Species: | C. beticola |
| Binomial name | |
| Cercospora beticola Sacc., (1876) | |
Cercospora beticola is a fungal plant pathogen which typically infects plants of the genus Beta, within the family of Chenopodiaceae. It is the cause of Cercospora leaf spot disease in sugar beets, spinach and swiss chard. Of these hosts, Cercospora leaf spot is the most economically impactful in sugar beets. Cercospora beticola is a deuteromycete fungi that reproduces using conidia. There is no teleomorph stage. C. beticola is a necrotrophic fungi that uses phytotoxins to kill infected plants. Yield losses from Cercospora leaf spot are around 20 percent.[1][2]
Hosts and Symptoms
Hosts of Cercospora beticola include sugar beets, swiss chard and other leafy greens. Symptoms include the random distribution of spots with brownish red rings which eventually cause leaf collapse.Older leaves will have spots of larger diameters. Signs are not observable by the unaided eye[1][2]
Disease Cycle
Stroma in field debris starts the life cycle. Sporulation occurs and conidia are produced. Conidia are rain splashed and insect carried to new hosts where under humid and wet conditions they germinate and penetrate through stomata. These conidia germinate in microcycles until the end of the growing season. At the end of the growing season C. beticola produces stroma again as a survival structure. Microcycles like the one used by C. beticola are very effective at producing lots of conidia. Because these conidia are effective at penetrating the host, mycelium is not necessary and conidia produce their own conidia at each new infection. There have been no direct observations of sexual spores in C. beticola.[1][2][3]
Management
In organic copper was historically used to control C. beticola in the field though today fungicides are more common. C. beticola has been shown to have some resistance to benzimidazole class fungicides. As a result, experts often have recommended fungicide rotation to kill any potential fungicide resistant strains. Some varieties of sugar beet also show resistance to C. beticola, unfortunately they have all had low yields in lab tests. Today the most common fungicides used are QoI, Headline, Proline, Inspire SB, Eminent and Super Tin or Agri Tin[2][1]
External links
References
- 1 2 3 4 Weiland, John; Koch, Georg (2004-05-01). "Sugarbeet leaf spot disease (Cercospora beticola Sacc.)†". Molecular Plant Pathology. 5 (3): 157–166. doi:10.1111/j.1364-3703.2004.00218.x. ISSN 1364-3703.
- 1 2 3 4 "Monitoring Fungicide Sensitivity of Cercospora beticola of Sugar Beet for Disease Management Decisions".
- ↑ Jung, Boknam; Kim, Soyeon; Lee, Jungkwan. "Microcyle Conidiation in Filamentous Fungi". Mycobiology. 42 (1). doi:10.5941/myco.2014.42.1.1.