Diseases of Crops
<h1>DISEASES OF CROPS</h1> CONTENT <ol> <li>Meaning of Disease</li> <li>Diseases of Major Crops</li> <li>Causes of Diseases</li> <li>Brief Explanations on Disease-causing Organisms</li> <li>General Effects of Disease on Crop Plants</li> <li>Diseases of Major Crops (detailed)</li> </ol> <h2>Meaning of Disease</h2> A disease is a departure from normal state of health, presenting marked symptoms or outward visible signs. A disease is also defined as a condition of disorder in the functioning of the tissues of an organism. It is an unfavorable condition caused by infections by pathogens or deficiency or excess of some environmental factors which result in physiological and anatomical dysfunctions expressed in characteristic symptoms. <h2>Diseases of Major Crops</h2> The following are the diseases of major crops: (i) Cereals – Smut, rice blast, etc. (ii) Legumes - Cercospora, leaf spot, rosette, etc. (iii) Beverages - Cocoa black pod, coffee leaf rust, etc. (iv) Tuber - Cassava mosaic, bacterial leaf blight, etc. (v) Fruits - Citrus Gummosis, Diebacks, etc. (vi) Fiber - Black arm (bacterial blight of cotton) (vii) Vegetables - Root knot of tomato or okra, etc. (viii) Stored produce - Mould <h2>Causes of Diseases</h2> <h3>(i) Pathogen Diseases</h3> These are diseases caused by living microorganisms called pathogens. e.g.