<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.

<h1>PESTS OF CROPS</h1> CONTENT <ol> <li>Meaning of Crop Pests</li> <li>Classification of Crop Pests</li> <li>Name and Description of Important Insect Pests</li> </ol>   <h2>Meaning of Crop Pests</h2> A pest can be described as an organism, whether plant or animal, which causes economic damage to crop plants, livestock, man and his possessions. They attack crops on the field as well as in the store. They may harm crops directly or introduce diseases into them. Examples of pests are insects, rodents, higher parasitic plants, etc.   <h2>Classification of Crop Pests</h2> Pests are classified in different ways as follows: <ol> <li>Insect pests</li> <li>Non-insect pests</li> </ol>   <h3>Insect Pests</h3> These are the most serious pests of agricultural importance, and the group includes all insects which cause damages to crops and crop products. Examples of insect pests are grass hopper, weevils, beetles, white flies, termites, crickets and locusts. They feed on crops either on the field or in the store.   <h3>Non-insect Pests</h3> These are organisms other than insects which attack and feed on crops. They cause a lot of damages to crops though they are not as many as insect pests. Examples of non-insect pests include rodents like giant rats, grass cutter, monkeys, nematodes and birds. <img class="size-full wp-image-53333 aligncenter" src="https://classhall.com/wp-content/uploads/2019/08/non-insect-pests.jpg" alt="Pests of Crops - Non-insect pests" width="650" height="139" />   <h3>Classification of Insect Pests Based on Mouth Parts/Mode of Feeding</h3>

<h1>PESTS OF CROPS</h1> CONTENT <ol> <li>Other Important Pests and Nature of Damages to Crop Pests</li> <li>Broad Outline/Biology of Selected Insect Pests</li> <li>Preventive and Control Measures of Crop Pests</li> <li>Side Effects of Various Preventive and Control Measures</li> <li>Effects/Economic Importance of Pests</li> </ol>   <h2>Other Important Pests and Nature of Damages to Crop Pests</h2> The non-insect pests include: <ol> <li>Birds</li> <li>Rodents</li> <li>Nematodes</li> <li>Snails</li> </ol>   <h3>Birds</h3> Many kinds of birds feed on planted crops. They attack crops like fruits, grains, oil palm, etc. while on the field. For example, the weaver birds called Quela bird feed on millet, sorghum and rice. They eat the developing seeds and cause great losses on crops. Francolin feeds on tuber crops like cassava, yam, cocoyam and grain crop. Parrots also eat lots of fruits such as mango and cocoa. Weaver birds cause defoliation to oil palm leaves, reducing photosynthetic activities of the crops. <h3>Rodents</h3> These are mammalian pests which damage crops like young oil palm trees, vegetables, yam, cassava, rice and sugar-cane. Examples are rats, monkeys, giant rats, bats, squirrel, grass cutter and antelope. Squirrels and monkeys eat cocoa pods; bats eat lots of fruits like oranges and mangoes. Ground squirrel eats or digs out and eats newly planted seeds. Grass cutter cuts and eat cereals, cassava, sugar cane and young oil palms. Rats eat and destroy stored produce like grains and tubers. <h3>Nematodes</h3> These are species of worm present in the soil. From the soil, they enter into the root of crops like tomatoes and okra where they cause the root to grow swellings called root knots. When this happens the plants have stunted growth and reduced yield <h3>Snails</h3> They are serious pests and they feed on leaves and reduce their photosynthetic ability, yield and quality of vegetables.   <h3>Nature of Damage to Crops</h3> The nature of damage by some selected crop pest are shown in the table below:

<h1>WEEDS AND WEED CONTROL</h1> CONTENT <ol> <li>Meaning of Weeds</li> <li>Common Weeds</li> <li>Effects of Weeds on Crops and Economy</li> <li>Economic Importance of Weeds</li> <li>Characteristic Features of Weeds</li> <li>Methods of Weed Dispersal</li> <li>Methods of Controlling Weeds</li> </ol>   <h2>Meaning of Weeds</h2> Weeds are often called volunteer plants because they grow where they are not planted. They are plants which grow where they are not wanted. They can also be defined as”plants out of place”. They are usually unwanted, uninvited quests on farms.Also ,their growth interfere with that of cultivated crops and therefore constitute nuisance to crops, livestock or even man. An edible crop could become a weed if it grows where and when it was not planted, example maize growing on a land where cassava is planted is a weed.   <h2>Common Weeds</h2> Some of the common weeds include: