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It is a most common disease of radish and other Crucifers and also sweet potato in India. The obligate parasite fungus Albugo candida causes this disease. It is characterized by the formation of rust like white pustules on the leaves and stem. The pustules form large irregular erupted patches. In radish the plants become chlorotic, stunted and the tuber yield may be reduced. It is major problem in the yield. The disease can be controlled by introducing disease resistant crops, by using proper fungicides. The disease can also be controlled by killing the diseased crops in seed level or by destroying the diseased crops.

The tobacco leaves, a native of America was introduced into India during 17th century. There are two varieties of tobacco in India. The first recognized viral disease of plants is Tobacco disease caused by Tobacco Mosaic Virus. It begins with the discolorations along the veins of the youngest leaves. The typical mosaic symptom on the leaf is varying the degree of chlorosis. The development of chlorophyll is affected by the virus and leaves become pale in color. Mosaic symptom is followed by a blistered appearance of the leaves with leaf spots. Plants attacked at an early stage show stunted and malformed growth. The disease cause extensive damage by reduction in yield and quality of product. The control measures were to grow disease-resistant varieties and by destroying the infected plants at the seedling stage.