(a) Identify specimens E, F. G and H. {2 marks}
Specimen E, Specimen F; Specimen G; Specimen H;
(b) Name the part of the plant usually attacked by each of specimens E, F, G, and H. {2 marks}
(c) Give two ways by which each of the specimens damages crops. {8 marks}
(d) State three methods of controlling specimen E. {3 marks}
Explanation
a) ldentification of specimens:
- E - Maize weevil
- F - Cotton Stainer bug/Dysdercus
- G - Termite
- H - Grasshopper
(b) Part of Plant attacked by specimens
- E - Maize grains
- F - Cotton bolls/okro fruits/akee apple
- G - Crop stems/roots/grains of lodged cereals
- H - Plant leaves and young shoots
(c) Damages caused to crops;
Specimen E (Maize Weevil);
- Bores into the grains of maize and creates holes
- Destroys the embryo and hence prevents germination
- Eats the endosperm and reduces food value
- Vents serve as sites for secondary infections
Specimen F (Dysdercus/cotton stainer bug);
- Pierces into mature cotton bolls/okro fruit/akee apple
- Stains the cotton lint
- Vents created serve as sites for secondary infection
- Prevents good fruit formation in okro
- Causes premature drop of fruits
Specimen G (Termite);
- Chews the stem and roots of plants and tubers
- Weakens the stem and roots of plants and make them to lodge
- Destroys seed grains lying on the field
- Also creates tunnels for secondary infection
Specimen H (Grasshopper) ;
- Causes defoliation of crops
- Young shoots are destroyed
- Wounds left on the crops can serve as vents for secondary infection
- Buds are also destroyed
- Reduces the photosynthetic ability of crop plants
- Reduces the growth of crop plants
(d) Methods of Controlling specimen E (Maize Weevil);
- Dry grains very well before storing
- Harvest early soon after drying
- Store grains in air-tight containers/hermetic storage
- Apply pesticides to the grains before storage
- Fumigate storage facilities
- Use smoke to kill or ward off the weevils
- Store grains in hot dried pepper/neem extracts