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Home / Plant Pathogens

Plant Pathogens

Plant pathogens include fungi, viruses, viroids, bacteria, phytoplasmas, and nematodes - cause billions of dollars in economic losses each year to agriculture, landscape, and forest settings in the United States. These diseases damage natural ecosystems, reduce crop yields, lower product quality or shelf-life, and, sometimes, contaminate food and feed with toxic compounds.


Citrus greening bacterium symptoms: brown necrotic or aborted seeds in infected mandarin -- Photo by J.M. Bové, INRA Centre

USDA. NAL. National Invasive Species Information Center

Species profile for Citrus Greening also known as Huanglongbing, yellow shoot disease, or yellow dragon disease. Native to China the disease was found in Florida in 2005. The disease may threaten 20% of total citrus production.

Red Tomatoes on Vine

Science Daily. December 3, 2007.

Scientists at Wageningen University and Research Center have identified a new virus as the cause for the tomato disease known in Mexico as "Marchitez".

Red bay tree kill-off by laurel wilt (Raffaelea spp. fungus). Photo by James Johnson. Image number UGA2110024 Bugwood Network.

Susan Cerulean.

The laurel wilt fungus, Raffaelea lauricola is rapidly spreading along the U.S. southern coastal plain. The fungus is devastating native redbay trees, sole host to the caterpillar stage of the palamedes swallowtail butterfly.

USDA. Agricultural Research Service

Triangulation Identification for Genetic Evaluation of Risks (TIGER) is a new tool for the rapid identification of microbes in samples of soil, water, air, blood, or in plant materials.