Black rot is the most serious disease of crucifer crops world wide when environmental conditions are favorable. The disease affects primarily aboveground parts of plants at any stage of growth and causes high yield and quality losses, especially in tropical and subtropical regions during the rainy season. All vegetables in the crucifer family, including broccoli, Brussels sprouts, cabbage, cauliflower, Chinese cabbage, kale, mustard, radish, rutabaga, and turnip, are susceptible to black rot. Many cruciferous weeds such as Shepherd's Purse, wild mustard, and yellow rocket may also be hosts of this pathogen. Genera See text. ... Yield may mean: In economics, yield is a measure of the amount of income an investment generates over time (related to return on investment). ... Subtropical (or semitropical) areas are those adjacent to the tropics, usually roughly defined as the ranges 23. ... Broccoli is a plant of the Cabbage family, Brassicaceae (formerly Cruciferae). ... Cultivar Group Brassica oleracea Gemmifera Group The Brussels sprout (Brassica oleracea Gemmifera Group) is a cultivar group of cabbage cultivated for its small (typically 2. ... Percentages are relative to US recommendations for adults. ... Percentages are relative to US recommendations for adults. ... Chinese cabbage (Brassica rapa, chinensis group) is a Chinese leaf vegetable related to the Western cabbage. ... Kale (also called Borecole) is a form of cabbage (Brassica oleracea Acephala Group), green in color, in which the central leaves do not form a head. ... Species See text The mustards are several plant species in the genus Brassica whose proverbially tiny mustard seeds are used as a spice and, by grinding and mixing them with water, vinegar or other liquids, are turned into a condiment also known as mustard. ... Binomial name L. This article is about the vegetable. ... Binomial name Brassica napobrassica Mill. ... Trinomial name Brassica rapa rapa L. For similar vegetables also called turnip, see Turnip (disambiguation). ... Binomial name Capsella bursa-pastoris (L.) Medik. ... Species See text. ... Species See text Barbarea (Bar-ba-ré-a, Winter cress or Yellow rocket) is a genus of about 22 species of flowering plants in the family Brassicaceae, native to temperate regions of the Northern Hemisphere, with the highest species diversity in southern Europe and southwest Asia. ... A pathogen or infectious agent is a biological agent that causes disease or illness to its host. ...

The characteristic black rot symptom on most cultivated crucifer plants is the appearance of yellow, V-shaped lesions along the margins of leaves. The point of the V-shaped lesion is directed toward a vein. When lesions enlarge, wilted tissue expands toward the base of leaves. Eventually the diseased areas become necrotic and the veins turn black or brown. The infection may move down the vascular tissue of petioles and then spread up and down the stems. When stems and petioles of an infected plant are cut crosswise or lengthwise, the black-brown vascular tissue with yellowish bacterial slime is observed. These symptoms may be confused with Fusarium yellows, except that Fusarium causes brown vein discoloration without bacterial slime. Moreover, symptoms of black rot may vary according to age of host, host genus, species, and cultivar and even environmental conditions. For example, symptoms on cauliflower may appear as numerous black or brown specks, scratched leaf margins, black veins, and discolored curds. Many cruciferous weed species do not exhibit any of these characteristic symptoms even when infected. A lesion is a non-specific term referring to abnormal tissue in the body. ... In finance, a margin is collateral that the holder of a position in securities, options, or futures contracts has to deposit to cover the credit risk of his counterparty. ... In the circulatory system, a vein is a blood vessel that carries blood toward the heart. ... Necrosis (in Greek Νεκρός = Dead) is the name given to unprogrammed death of cells/living tissue (compare with apoptosis - programmed cell death). ... Cross section of celery stalk, showing vascular bundles, which include both phloem and xylem. ... Leaf of Dog Rose (Rosa canina), showing the petiole and two leafy stipules In botany, the petiole is the small stalk attaching the leaf blade to the stem. ... Transformers: Robots in Disguise (2001) RiD Crosswise Crosswise (X-Car in japan) was the name of one of the Autobot Spychangers. ... Fusarium is a large genus of filamentous fungi widely distributed in soil and in association with plants. ... Percentages are relative to US recommendations for adults. ... Curdled is also the name of a Quentin Tarantino film. ...

Black rot of crucifer is caused by a bacterium, Xanthomonas campestris pv. campestris (Xcc). The bacteria can overwinter in plant debris, in and on seeds from diseased plants, and in and on weeds. The pathogen may survive in diseased crop residue buried in soil for up to 2 years, but not more than 60 days free in soil. The major source of these bacteria is infected seeds, which enable long-distance spread of the disease. The pathogen is spread within and between fields by splashing water, wind, insects, machinery, and irrigation or drainage waters. The bacteria infect the cotyledons and young leaves through natural plant openings (stomata, hydathodes) or wounds and then migrate between cells until they reach the xylem tissue where they spread throughout the plant. Free moisture is required for infection by the pathogen. After infection, symptoms may appear on plants within 7 to 14 days under optimum conditions (25 to 30 degrees C).

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