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Publication #PP 238

Colletotrichum Crown Rot (Anthracnose Crown Rot) of Strawberries1

Natalia A. Peres and Steven J. MacKenzie 2

Colletotrichum crown rot is caused by the fungi Colletotrichum gloeosporioides and Colletotrichum fragariae. Both pathogens kill strawberry plants by aggressively invading crown tissue. Crown rot is a serious disease in warm production regions, such as those in the southeastern United States, since both C. fragariae and C. gloeosporioides grow and reproduce best at temperatures greater than 25oC. Although crown rot is observed in fields during the winter production season in Florida, it is most severe in nurseries in the southeastern United States and is one of the primary reasons that transplant production moved to cooler regions. A third species of Colletotrichum, C. acutatum, also causes plants to decline in vigor and wilt. Although it is sometimes isolated from crown tissue, decline and wilt symptoms caused by this species are generally due to bud and root infection.

Causal agent and symptoms

The symptoms caused by C. gloeosporioides and C. fragariae are virtually indistinguishable from one another in the field. Plants infected with virulent strains initially show signs of water stress and subsequently collapse (Fig.1). This process may occur relatively rapidly, taking only 2 or 3 days at high temperatures. At low temperatures, plants may show initial signs of stress but it could take several weeks before they collapse. Cutting through the crown tissue of infected plants lengthwise reveals a reddish-brown, firm rot (Fig.2). Infected (asymptomatic) plants from nurseries may grow normally for some time before symptoms occur. There are typically no lesions on foliage or stolons in production fields, although, under greenhouse conditions or in summer nurseries, necrosis on stolons, lesions on fruit, or black leaf spots may be visible. Symptoms of Colletotrichum crown rot may be confused with those of Phytophthora crown rot. To confirm a diagnosis, the pathogen must be isolated from the diseased crowns and identified in the laboratory.

Disease development and spread

Plant propagation in Canada and northern states for the Florida production season has greatly reduced the incidence of Colletotrichum crown rot. Currently, during the warm months at the beginning and end of the production season, crown rot incidences up to 5% still occur on plants in Florida fields. Plants can become infected after transplant since C. gloeosporioides strains pathogenic to strawberry are abundant on noncultivated hosts in Florida, and genetic data indicate that they are from the same population as those from strawberry crowns. C. fragariae has also been isolated from at least one native host in Florida and also from some ornamental species. Although inoculum from plants showing symptoms at the beginning of a production season can spread to other plants by the end of the season, the disease does not appear to be multicyclic and usually does not spread quickly from symptomatic to healthy plants. In southern nurseries, higher temperatures and frequent rains favor inoculum spread among strawberry plants. Colletotrichum spp. responsible for crown rot do not appear to survive between seasons on plant debris when plants are killed immediately after the production season ends in the spring and the fungus disappears from crowns, plant residues, and soil during the hot and humid summer months in Florida.

There are no known cultivars that are immune to Colletotrichum crown rot, although cultivars do differ in susceptibility. The use of tolerant cultivars delays the onset of disease until later in the season or reduces the incidence of crown rot. Cultivars such as 'Strawberry Festival', 'Camarosa', and 'Camino Real' are considered susceptible, whereas 'Sweet Charlie' and 'Florida Radiance' show moderate levels of resistance. 'Treasure' and 'Florida Elyana' display the highest level of resistance to crown rot of the cultivars that we have tested. Resistance to crown rot caused by C. gloeosporioides and C. fragariae appears to be highly correlated. Although there may be some correlation between resistance to crown rot and resistance to Anthracnose fruit rot caused by C. acutatum, the correlation is not high, as illustrated by the fact that 'Treasure' is highly resistant to Colletotrichum crown rot but highly susceptible to Anthracnose fruit rot.


Using disease-free transplants is the most effective method for controlling Colletotrichum crown rot in strawberry production fields. Currently, there is no certification program to guarantee that transplants are free of crown rot, and infected plants may not show symptoms until they have been established in the field. Transplants from northern latitudes or high-altitude nurseries should be used to grow crown rot-free plants in Florida fields. Weekly foliar sprays of protectant fungicides such as captan are very effective in controlling the spread of crown rot from infected to healthy plants and may reduce infections coming from native vegetation. However, protectant fungicides do not hinder the progress of symptoms in plants that are already infected. Cultural practices that reduce the occurrence and movement of water on foliage, such as the use of drip irrigation, limits the dispersal of the pathogen. Plants are also more sensitive to infection under high fertility conditions. Reduced nitrogen rates in nurseries or the use of nitrate rather than ammonium nitrogen sources may also reduce risk.

Figure 1. 

Initial symptoms of Colletotrichum crown rot



[Click thumbnail to enlarge.]

Figure 2. 

Collectotrichum crown rot (internal crown symptoms)



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Table 1. 

Products recommended for control of Colletotrichum crown rot of strawberries in Florida

Product name

(active ingredient)



Maximum rate/A

Minimum days to harvest





Per application

Per season

Captan 80 WDG (captan)


3.75 lb.

30 lb.



Do not apply in combination with or immediately before or closely following oil sprays. Do not mix with strongly alkaline materials.

Captec 4L®



3 qt.

54 qt.



Do not apply in combination with or immediately before or closely following oil sprays. Do not mix with strongly alkaline materials.



(thiophanate methyl)


See label

See label



Do not apply more than four applications per year.




15.4 fl. oz.

1.92 qt.



Do not make more than two consecutive applications and no more than four applications per crop per year.

Cabrio® EG (pyraclostrobin)


14 fl. oz.

70 fl. oz.



Do not make more than two consecutive applications and no more than five applications per crop per year.

Switch® 62.5 WG (cyprodinil + fludioxonil)

9 + 12

14 oz.

56 oz.



Do not make more than two consecutive applications. Do not plant crops not on the label for 30 days after last application.

a Fungicide group (FRAC Code): Numbers (1-37) and letters (M) are used to distinguish the fungicidal mode of action groups. All fungicides within the same group (with same number or letter) indicate same active ingredient or similar mode of action. This information must be considered in making decisions about how to manage fungicide resistance. M=Multi-site inhibitors, fungicide resistance is low; NC= not classified. Source: (Fungicide Resistance Action Committee, FRAC).

Always read a current product label before applying any chemicals.



This document is PP 238, one of a series of the Plant Pathology Department, Florida Cooperative Extension Service, Institute of Food and Agricultural Sciences, University of Florida. Original publication date June 2007. Revised September 2012 and May 2013. Visit the EDIS website at


Natalia A. Peres, associate professor, and Steven J. MacKenzie, former research coordinator, Plant Pathology Department, Gulf Coast Research and Education Center, Cooperative Extension Service, IFAS, University of Florida, Gainesville, FL 32611.

The use of trade names in this publication is solely for the purpose of providing specific information. UF/IFAS does not guarantee or warranty the products named, and references to them in this publication do not signify our approval to the exclusion of other products of suitable composition. All chemicals should be used in accordance with directions on the manufacturer's label.

The Institute of Food and Agricultural Sciences (IFAS) is an Equal Opportunity Institution authorized to provide research, educational information and other services only to individuals and institutions that function with non-discrimination with respect to race, creed, color, religion, age, disability, sex, sexual orientation, marital status, national origin, political opinions or affiliations. For more information on obtaining other UF/IFAS Extension publications, contact your county's UF/IFAS Extension office.

U.S. Department of Agriculture, UF/IFAS Extension Service, University of Florida, IFAS, Florida A & M University Cooperative Extension Program, and Boards of County Commissioners Cooperating. Nick T. Place, dean for UF/IFAS Extension.