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This question was quite unpopular among the candidates. In 6(a), most of the candidates could not use the appropriate conjunctions/table to differentiate between afforestation and deforestation. Further to this, majority of the candidates could not discuss the viral disease of maize under name of diseases, mode of transmission, symptoms and two control measures. More so, in 6(c-d), most of the candidates could neither state four advantages of vegetative propagation nor mention three planting materials for banana cultivation.
The expected answers include:
6(a) Difference between afforestation and deforestation
Afforestation is the process by which tree seedlings are planted on a piece of land
whereas, on the other hand/
Deforestation is the removal of economic trees from a piece of land as a result of human activities.
(b) Discussion of viral disease of maize
Maize streak
-Transmitted by a piercing and sucking insect called Leaf hoppers.
(iii) Symptoms
- The leaf surface is discoloured in the form of streak running parallel to the veins
- Stunted/deformed crops
- Control measures
- Plant early
- Remove and destroy infected crops
- Spray insect vectors (leaf hoppers) with insecticides
- Use disease resistant varieties.
(c) Advantages of Vegetative Propagation
- Pollination agents are not required
- Hazards of fertilization are avoided
- Offspring are true to type
- Means of propagating seedless plants
- Early maturity
- Can be used to control certain diseases e.g. Tristeza of citrus
- Can have different kind of varieties of the same crop on one root
stock
- Used to repair wounds on trees
- For virus indexing
- To change plant form
- Could be used to increase crop yield
(d) Planting materials for banana cultivation
- sword suckers
- bits
- peepers
- slips
- maiden
- water suckers
- suckers/pup
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