Observation

 

This question was well attempted by candidates. Majority of the candidates correctly named the organism which causes the damage observed on specimens J, K, L and M.

• Most candidates were unable to state correctly ways in which the organism which caused the damage in specimen J (maize grains) is of economic importance.

   (c) Candidates could not state the ways of controlling maize weevil, yam beetle, cassava
mosaic virus and fruit rot of tomato.

The expected answers include:
3. (a)    Organisms which cause the damage observed in specimens J, K, L and M
Specimen J -   Maize weevil
                      Specimen K  - Yam beetle
                      Specimen L -   Virus
                      Specimen M -  Fungus                                                 

(b)    Economic importance of maize weevil

• Causes loss of food/ food shortage/destruction of stored maize
• Destruction of seed viability/reduced seed germination
• Causes loss of income/reduced market value
• Increases the cost of production due to the cost of controlling the pest
• It reduces yield/quantity of produce
(c)     Ways of controlling maize weevil,  yam beetle , cassava mosaic virus and
fruit rot of tomato  
Maize weevil

• Use of dry hot pepper/use of pepper
• Store in air tight containers
• Use of appropriate insecticide
• Heat treatment/ store on rafters in smoky rooms
• Use of deep freezer/freezing
• Early harvesting of crops
• Fumigating maize in store

                                                                            
Yam beetle

• Treat yam setts/seeds yams with appropriate insecticides
• Crop rotation
• Late planting
• Hand picking and destroying

 

Cassava mosaic virus

• Plant resistant varieties
• Uproot and burn infected plants
• Farm sanitation
• Plant clean and disease-free stem cuttings
• Spray insecticides to kill the vectors                                                                           

 Fruit rot fungus

• Use of resistant varieties
• Remove infected plants
• Staking of tomato plants
• Treating soil with copper based fungicide