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Sp661 Bacterial Leaf Scorch In Landscape Trees, The University Of Tennessee Agricultural Extension Service

Forestry, Trees, and Timber

Bacterial leaf scorch is a chronic disease caused by a bacterium, Xylella fastidiosa, that grows in the xylem of the tree and physically clogs these water-conducting vessels. As the bacterium multiplies, water transport becomes more limited. The tree suffers water stress, especially in mid to late summer, resulting in leaf scorch; a browning or discoloration of the margins of the leaves with interior portions of the leaves near the veins remaining green. The bacterium is spread by leafhoppers, spittlebugs and other xylem-feeding insects.

Sp277-W Foliar Diseases Of Tomato, The University Of Tennessee Agricultural Extension Service

Field & Commercial Crops

No abstract provided.

Sp277-Q Black Shank Of Tobacco, The University Of Tennessee Agricultural Extension Service

Field & Commercial Crops

Black shank is a widespread and destructive disease of tobacco in Tennessee. It was first identified in Robertson County in 1935 and has since spread to most tobacco-producing counties in the state. Burley, dark air-cured and dark fire-cured types of tobacco are all susceptible to black shank.

Black shank disease is caused by a soil-borne fungus, Phytophthora parasitica f. nicotianae. The fungus can survive in the soil for many years, even in the absence of tobacco.

Sp370-C-Tomato Wilt Problems, The University Of Tennessee Agricultural Extension Service

Home Garden, Lawn, and Landscape

There are many possible causes of wilting of tomato plants. Successful treatment of the problem depends on accurate diagnosis and appropriate preventive measures. Some of the major causes of wilting are discussed below.

Sp641-Tennessee Farm-Level Economic Implications Of Soybean Rust, The University Of Tennessee Agricultural Extension Service

Marketing, Finances and Value-Added Agriculture

Asian Soybean Rust (here after referred to as “rust”) is a potentially devastating crop disease. It now afflicts soybean production in the Eastern Hemisphere and in the Western Hemisphere south of the equator. The first case of rust in the continental United States was confirmed on November 10, 2004. While the extent of the outbreak is not known, concern over the long-range impact of rust on U.S. soybeans has grown as a result of the confirmation.

Many federal and state agricultural agencies have begun preparations for such an outbreak. Defined protocols have been developed in some states for better agency …