(a) Describe the life cycle of the variegated grasshopper. (b) List five ways through which diseases are spread on crop farms. (c) List six characteristics of a good layer.
Explanation
a)Description of life cycle of the variegated grasshopper
-Adults male and female mate -The female lays eggs underneath leaves -The eggs hatch into nymphs around October/onset of dry season - During the fourth instar stage, they migrate into the farm and continue to feed on leaves up to the adult stage - It undergoes incomplete metamorphosis.
(b) Ways through which diseases are spread on crop farms - Harbouring of pathogens by weeds - Contaminated irrigation water - Rain splash - Insect vectors/pest infestation - Use of infected planting materials Wind dispersal of pathogens - Use of contaminated tools equipment - Uncontrolled movement of visitors to the farm - Animal dispersal of pathogens especially during feeding - Dews - Soil/soil borne pathogens
(c) Characteristics of a good layer - Presence of short beak - Large, bright red comb - Soft and pliable abdomen - Broad breast bone - Broad and square head - Large, oval, moist, warm and smooth vent - Glossy plumage/feather - Bright eyes - Smooth and lean face - Absence of cannibalistic behaviours - Broad, flexible pelvic bones - Dilating cloaca - Soft
