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Date: Wed 1 Feb 2023
Source: Specialty Crop Industry [summ. Mod.DHA, edited]
https://specialtycropindustry.com/target-spot-disease-increasing-in-south-florida-tomatoes/


Target spot is increasing in tomatoes in southwest Florida. The disease can be confused with bacterial spot or early blight, laboratory diagnosis is needed to ensure correct identification. On tomato, symptoms consist of brown-black lesions with concentric rings giving them a target-like appearance. Lesions on fruit will become larger and coalesce on maturation, leading to large pitted areas.

An integrated approach is needed for management of the disease, such as crop rotation without solanaceous crops, as well as removal of volunteer and weed species that can serve as pathogen reservoirs. There are also chemical options, according to University of Florida research trials.

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Communicated by:
ProMED

[Target spot of tomato is caused by the fungus _Corynespora cassiicola_. The pathogen is seed and soil borne, it can survive for several years in soil and infected crop residues; spores can also be spread by wind. Disease management may include methods to reduce inoculum (removal of pathogen reservoirs and crop residue), adjusting planting times, crop rotation (for example with cereals) and fungicides (seed treatments, foliar sprays). For tomato and some other crops, varieties with increased levels of resistance or tolerance exist.

_C. cassiicola_ has a wide host range including solanaceous crops (tomato, capsicum, aubergine); cucurbits (cucumber, squash); soybean, papaya, cowpea, cotton, as well as ornamental species. The pathogen is found worldwide, but different strains may be restricted to certain hosts or areas.

Maps
USA (with states):
https://www.orangesmile.com/common/img_country_maps/usa-map-0.jpg

Pictures
Target spot symptoms on tomato:
https://d3qz1qhhp9wxfa.cloudfront.net/growingproduce/wp-content/uploads/2012/01/30138.jpg,
https://www.gardeningknowhow.com/wp-content/uploads/2016/02/target-spot-tomatoes.jpg,
https://apps.lucidcentral.org/ppp_v9/images/entities/tomato_target_spot_163/img_3478a.jpg,
https://barmac.com.au/wp-content/uploads/sites/3/2016/01/Target-Spot-Tomato1.jpg,
https://apps.lucidcentral.org/pppw_v10/images/entities/tomato_target_spot_163/img_4366.jpg and
https://plantpath.ifas.ufl.edu/u-scout/tomato/target-spot.html (photo gallery)

Links
Information on target spot of tomato:
https://www.growingproduce.com/vegetables/tomatoes/pest-of-the-month-target-spot-of-tomato/,
https://apps.lucidcentral.org/ppp_v9/text/web_full/entities/tomato_target_spot_163.htm,
https://www.vegetables.bayer.com/ca/en-ca/resources/agronomic-spotlights/target-spot-of-tomato.html,
https://edis.ifas.ufl.edu/publication/pp351 and
https://www.gardeningknowhow.com/edible/vegetables/tomato/target-spot-on-tomatoes.htm
Information on _C. cassiicola_:
https://mycocosm.jgi.doe.gov/Corca1/Corca1.home.html,
https://gd.eppo.int/taxon/CORYCA,
https://doi.org/10.1111/jph.12992 and
https://doi.org/10.1094/PHP-05-18-0023-RV
_C. cassiicola_ taxonomy and synonyms:
http://www.indexfungorum.org/names/NamesRecord.asp?RecordID=296024 and
http://www.speciesfungorum.org/Names/SynSpecies.asp?RecordID=296024
- Mod.DHA

ProMED map:
Florida, United States: https://promedmail.org/promed-post?place=8708198,212]

See Also

2010
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Corynespora blight, sesame - India: (MP) 20101010.3686
2003
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Target leaf spot, cucumber - Korea, South 20030121.0190

Website: http://www.isid.org

Published: February 7, 2023