Collar rot is a symptomatically described disease that is usually caused by any one of various fungal and oomycete plant pathogens. It is present where the pathogen causes a lesion localized at or about the collet between the stem and the root. The lesions develop around the stem eventually forming a "collar". Observationally, collar rot grades into "basal stem rot", and with some pathogens is the first phase of "basal stem rot" often followed by "root rot". Collar rot is most often observed in seedings grown in infected soil. The pathogens that cause collar rot may be species or genera specific. But generalist pathogens such as Athelia rolfsii (aka Sclerotium rolfsii) are known to attack over 200 different species. While bacteria caused collar rot is not common, trees infected with Fire blight (Erwinia amylovora) may develop collar rot. Non-parasitic collar rot may be caused by winter damage.
The symptomatically described disease Southern blight is often the first observed precursor of the collar rot caused by the fungus Athelia rolfsii. Causally known as Sclerotial blight, Athelia rolfsii survives in the soil as sclerotia, and in infected decomposing plant material as mycelia.
Collar rot that is caused by the oomycete Phytophthora is causally called Phytophthora collar rot, and is a common disease of fruit and nut trees, as well as other flowers and crops. Phytophthora species remain in the soil, as spores, and in infected plant tissue, as mycelia, so absent control measures (sterilization, toxic applications) the disease continues so long as susceptible plants are grown in that soil.
Hosts and agentsEdit
- In carnations (Dianthus caryophyllus) by Alternaria dianthi,
- In chili (Capsicum) by Phytophthora,
- In cinchona (Cinchona officinalis) by Phytophthora quininea,
- In Chinese evergreens (Aglaonema) by Fusarium subgutinans,
- In coffee plants (Coffea) by Gibberella stilboides,
- In dogwoods (genus Cornus) by Phytophthora cactorum where the disease is also called "crown canker",
- In eggplant/brinjal (Solanum melongena) by Sclerotinia sclerotiorum and Sclerotium rolfsii,
- In elephant foot yams (Amorphophallus paeoniifolius) by Sclerotium rolfsii,
- In fruit and nut trees by a variety of pathogens including Sclerotium rolfsii, Alternaria and Phytophthora,
- In groundnut/peanut (Arachis hypogaea) by Aspergillus niger which also causes wilt and crown rot, and by Lasiodiplodia theobromae,
- In hardwoods and conifers by Phytophthora cinnamomi,
- In maize (corn, Zea mays) by Sclerotium rolfsii,
- In papaya by Calonectria,
- In pines by both Phytophthora and Diplodia pinastri,
- In rhododendron, China aster, marigold, gloxinia and zinnia by Phytophthora cryptogea,
- In sunflowers by Sclerotium rolfsii, and by Phytophthora cryptogea.
- In sweet potatoes (Ipomoea batatas) by Sclerotium rolfsii,
- In tobacco by Sclerotinia sclerotiorum.
- In tomatoes (Solanum lycopersicum) by Alternaria solani,
Notes and referencesEdit
- Ahmad, Yasmin; Mirza, M. Siddique,; Aslan, M. (1988). "Collar Rot of Maize caused by Sclerotium rolfsii in Pakistan" (PDF). Pakistan Journal of Agricultural Research. 9 (4): 604–605. Archived (PDF) from the original on 2 November 2014.CS1 maint: Multiple names: authors list (link)
- Horst, R. Kenneth, ed. (2008). Westcott's Plant Disease Handbook (seventh ed.). Dordrecht: Springer Verlag. p. 105. ISBN 978-1-4020-5193-7.
- Horst 2008, p. 720
- Ames, Teresa. "Sweetpotato Diagnotes: Sclerotial blight". Centre for Biological Information Technology (CBIT), The University of Queensland.
- Hartman, John; Beale, Julie; Bachi, Paul. "Plant Pathology Fact Sheet: Root and Collar Rots of Tree Fruits" (PDF). College of Agriculture, University of Kentucky. Archived (PDF) from the original on 4 December 2008.
- Thomson, Sherman V.; Scott, C. Ockey (1998). "Utah Pests Fact Sheet: Phytophthora Crown and Collar Rot". Utah Plant Disease Control No. 6. Utah State University Extension and Utah Plant Pest Diagnostic Lab (UPPDL). Archived from the original on 19 March 2012.
- Horst 2008, p. 511
- Erwin, D. C.; Bartnicki-Garcia, S.; Tsao, P. H. (1983). Phytophthora, its Biology, Taxonomy and Pathology. St. Paul, Minnesota: The American Phytopathological Society. ISBN 978-0-89054-050-3.
- Gulya, Thomas J.; et al. (2012). "Sunflower Diseases Remain Rare in California Seed Production Fields Compared to North Dakota". Plant Management Network. Archived from the original on 21 November 2014.
- Agrios, George N. (1988). "Phytophthora Foot, Crown, Collar, Stem, or Trunk Rots". Plant Pathology (third ed.). Burlington: Elsevier. pp. 301–306. ISBN 978-0-323-13969-4.
- Horst, R. Kenneth (2013). Field Manual of Diseases on Garden and Greenhouse Flowers. Dordrecht: Springer Verlag. p. 43. doi:10.1007/978-94-007-6049-3. ISBN 978-94-007-6049-3.
- Akter, M. K.; et al. (2007). "Pathogenicity of Phytophthora capsici and possibilities of its biological and chemical control" (PDF). Journal of Agroforestry and Environment. 1 (2): 81–84. Archived from the original (PDF) on 21 November 2014. Retrieved 22 November 2014.
- Crandall, Bowen S. (1950). Cinchona root and collar rot in Peru and Bolivia. Circular no. 855. Washington, DC: United States Department of Agriculture.
- Horst 2008, p. 484
- Baker, Celia J. (1970). "Coffee bark disease in Kenya". Kenya Coffee. 35 (414): 226–228.
- Snover-Clift, Karen; Jensen-Tracey, Sandra (2011). "Crown Canker of Dogwood, Phytophthora cactorum" (PDF). Department of Plant Pathology and Plant-Microbe Biology, Cornell University. Archived (PDF) from the original on 14 June 2012.
- Horst 2008, p. 260
- Reddy, P. Parvatha (2014). "Solanaceous Vegetable Crops, 8.3.2 Collar Rot, Sclerotinia sclerotiorum, Sclerotium rolfsii". Plant Growth Promoting Rhizobacteria for Horticultural Crop Protection. New Delhi, India: Springer Verlag. pp. 162–163. doi:10.1007/978-81-322-1973-6. ISBN 978-81-322-1972-9.
- Pravi, V.; Jeeva, M. L.; Archana, P. V. (2014). "Rapid and Sensitive Detection of Sclerotium rolfsii Associated with Collar Rot Disease of Amorphophallus paeoniifolius by Species-Specific Polymerase Chain Reaction Assay". Molecular Biotechnology. 56 (9): 787–794. doi:10.1007/s12033-014-9757-x. PMID 24788585.
- Khan, Aslam (2001). Plant Diseases. Delhi, India: Kalpaz Publications. pp. 99–102. ISBN 978-81-7835-052-3.
- Khan 2001, pp. 47–49
- Kishore, G. Krishna; Pande, S.; Podile, A. R. (2005). "Biological control of collar rot disease with broad-spectrum antifungal bacteria associated with groundnut" (PDF). Canadian Journal of Microbiology. 51 (2): 123–132. doi:10.1139/w04-119. PMID 16091770. Archived (PDF) from the original on 31 October 2014.
- Horst 2008, p. 491
- Horst 2008, p. 509
- Horst 2008, p. 463
- Horst 2008, p. 475
- Mizra, S. M.; Khokhar, L. K. (1985). "Occurrence of sunflower collar rot diseases caused by Sclerotium rolfsii in Pakistan". Helia. 8: 41–43.
- Gulya, Thomas; Rashid, Khalid Y.; Masirevic, Stevan M. (1997). "Sunflower diseases". In Schneiter, Albert A. (ed.). Sunflower technology and production. Madison, Wisconsin: Soil Science Society of America. pp. 263–379. doi:10.2134/agronmonogr35.c6. ISBN 978-0-89118-227-6.
- Virginia Polytechnic Institute (31 December 2008). "Disease Management Research for Virginia Tobacco". Research, Education & Economics Information System, United States Department of Agriculture.
- Horst 2008, p. 456
- Maiero, Marisa; Ng, Timothy J.; Barksdale, Thomas H. (1990). "Inheritance of Collar Rot Resistance in the Tomato Breeding Lines C 1943 and NC EBR-2" (PDF). Phytopathology. 80 (12): 1365–1368. doi:10.1094/phyto-80-1365.
- Symptoms of rootstock blight can be confused with Phytophthora collar rot. Johnson, Kenneth B. (2005). "Fire blight of apple and pear". The Plant Health Instructor. doi:10.1094/PHI-I-2000-0726-01. Archived from the original on 3 February 2012.