The Plant Diagnostic Center is a service of the LSU AgCenter and is supported by the Department of Plant Pathology and Crop Physiology. Routine plant diagnostic services are provided to extension personnel across Louisiana as well as to state residents at a charge of $20 per sample. The center diagnoses plant samples with problems caused by fungi, bacteria, viruses, nematodes, insect pests and mites, as well as nonpathogenic agents and weed identification
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Mirlitons are susceptible to a common fungal disease called powdery mildew. Mirliton powdery mildew is caused by Podosphaera xanthii.
Oleander leaf scorch (OLS) is a deadly disease of oleander that was first reported in California in the early 1990s.
Rose rosette disease is caused by a virus known as Rose rosette virus. It is a devastating disease of roses – particularly since all cultivars are susceptible.
Downy mildew of sweet basil is a destructive disease that was first detected in the United States in 2007.
Citrus greening, also known as yellow shoot disease or huanglongbing, is one of the most devastating diseases of citrus worldwide.
Lichens are fascinating plants. They are composed of two different organisms – a fungal partner and a photosynthetic partner living in a symbiotic relationship.
Bacterial gall on Loropetalum (Loropetalum chinense) is caused by a plant pathogenic bacterium called Pseudomonas savastanoi.
Sweet olive is susceptible to a bacterial disease called leaf scorch, which is caused by Xylella fastidiosa.
Boxwood blight, also known as box blight, is a fungal disease caused by Calonectria pseudonaviculata (Cylindrocladium pseudonaviculata, C. buxicola).
Bitter rot of apple is a fungal disease commonly caused by two species known as Colletotrichum gloeosporioides and C. acutatum.
Like Spanish moss, ball moss is an epiphyte and belongs to family Bromeliaceae.
Citrus canker is a bacterial disease caused by Xanthomonas citri subsp. citri. It is thought to have originated in Southeast Asia.
Large patch is the most common disease of warm-season turfgrasses in Louisiana. This disease is caused by the soilborne fungus Rhizoctonia solani.
Take-all root rot is caused by the soilborne fungus Gaeumannomyces graminis var. graminis (Ggg), frequently is found in association with turfgrass roots.
Texas Phoenix palm decline is a fatal disease of palms. Also called date palm lethal decline, it had only been found in Florida and Texas until recently.
In Louisiana, Canary Island date palm (Phoenix canariensis Hort. Ex Chabaud) is a signature palm planted in New Orleans and nearby cities.
Twenty-six kindergarteners from the University Laboratory School visited the department of Plant Pathology and Crop Physiology on April 28, 2016.
This publication is intended to introduce home vegetable gardeners to the various methods used to manage the many diseases that affect these crops. (PDF Format Only)
Use this Form to Submit Plant Disease/Insect/Mite/Weed Samples For Diagnosis/Identification.
Gray leaf spot occurs on a wide range of turfgrasses throughout the United States. In Louisiana, it is most commonly seen on St. Augustine grass but occasionally can be a problem for Bermuda grass or centipede grass as well. This publication describes how to identify and manage this disease. (PDF Format Only)
We often see lawns with mushrooms or doughnut rings of dying or dark green grass. These are referred to as "fairy rings." This publication includes information on how to control fairy rings in your lawn. (PDF Format Only)
Nematode assay form is now available as a fill-in form. It should be included with all samples submitted for nematode analysis.
The LSU AgCenter Plant Diagnostic Center diagnoses plant samples with problems caused by fungi, bacteria, viruses, nematodes, insects pests and mites, as well as nonpathogenic agents. .
Leaf and crown rot is a common problem on liriope (or lily turf) in both nursery and landscape settings. All species and cultivars of liriope are reported to be susceptible to this disease. Proper identification is the key to sucessful disease management. This fact sheet is intended to aid in the identification and management of this disease. (PDF format only)
Proper identification is the key to sucessful disease management. This fact sheet is intended to aid in the identification and management of this disease. (PDF format only)
Tomato yellow leaf curl is a relatively new whitefly-transmitted virus disease of tomatoes in the United States. It was first observed in South Florida in 1997 and has since spread throughout much of the Southeast, including Louisiana where it was first observed in 2000. Proper identification is the key to successful disease management. This fact sheet is intended to aid in the identification and management of this disease of tomatoes. (PDF Format Only)
The southern root-knot nematode (Meloidogyne incognita) is a widespread problem in Louisiana. This pest favors the soils where most vegetables are produced and has been found in about 25 percent of the vegetable gardens in our state. This nematode can be extremely damaging to some crops and causes severe losses. (PDF Format Only)
Solanum melongena L. (eggplant) is a member of Solanaceae family. This is frost-tender herbaceous perennial, usually grown as an annual plant. Diseases such as Verticillium wilt, Southern blight, Phomopsis blight, Anthracnose fruit rot and Altenaria blight are commonly associated with eggplant and can reduce its harvestable yield significantly.
Proper identification is the key to successful disease management. This fact sheet is intended to aid in distinguishing among three common foliar diseases of watermelon. (PDF Format Only)
Proper identification is the key to successful disease management. This fact sheet is intended to aid in the identification and management of phytophthora blight on peppers. (PDF Format Only)