The following relevant questions and their answers in this topic will greatly motivate and help the           user to comprehend and understand the required concepts and practices:

1. State two possible causes of swelling on the roots of legume crops
2. Discuss the various cultural methods of controlling pests in crops
3. What does the term ‘close season’ mean in crop production?                                             
4. Explain five cultural methods of pest control in stored grains            
5. Name four symptoms of viral infections in plants
6. Study the illustrations given below and then answer the questions that follow:-

            (a) Identify the pests shown by the illustrations B, C and D                                                 

            (b) State one effective method of controlling the pest labelled                                            

            (c) Name the type of crop commonly attacked by the pest labelled ‘C’                               

7. State the various practices carried out in the field to help control crop diseases                  
8. State two ways in which pesticides kill crop pests

9. The diagram below shows kale seedling attacked by a pest

            (a) Identify the pest   

            (b) What damage does the pest cause to the crop                                                                  

            (c)  State two methods of controlling the pest

11. Define the term ‘economic injury level of a pest and integrated pest control management
12. List four harmful effects of crop pests           
13. The diagram below shows a fungal disease in a section of potato crop leaf

1. a) Identify the fungal disease                                                                                                          
2. b) (i) State  the causal  organism of  the disease identified above                                                         
3. ii) Give two symptoms of the above disease                                                                                    
4. c) Give two control measures of the disease                                                                                        
5. The diagram below shows a banana fruit infected by a certain disease.

• Identify the disease                                                                                                         
• Suggest any one control measure for the disease you have named in (a)

15. The diagram below shows a crop pest;

            (a) Identify the crop pest                                                                                                       

(b) State two damages the pest would cause to crops                                                           

16. Give two symptoms of nematode attack on bananas.
17. Give four cultural practices used in controlling crop pests
18. State three symptoms of coffee berry disease.            

19        (i) Use the diagrams below to answer the question that follow.                                           

            (a) Identify the crop pests labeled M, N and P                                                                     

            (b) State one control measures of crop pests labeled M                                                                   

            (c) State the damage caused to crops by crop pest labeled N                                                

20. State and explain the cultural methods of pest control

CROP PESTS AND DISEASES

1. two possible causes of swelling on the roots of legume crops

• Infection by nematodes

Nodulation/ nitrogen fixing bacteria  

2. the various cultural methods of controlling pests in crops

• Timely planting-done early e.g. maize escape stalk borer
• proper  tillage-to expose  soil boring pest i.e. white grubs
• Timely harvesting-enables crops i.e.  maize to escape weevil attacks
• close season-avoids  growing  susceptible crops for   some period to control pink worms in cotton
• trap cropping-plant  crops together with main crop  to  trap/attract pests before they attack e.g. sorghum round the  maize plantation
• trap rotation-rotate crops preferred  by certain  pests  with those  which are  not e.g. groundnuts and  potatoes rotated with maize  and beans to starve  pests
• establishing resistance crop varieties-this enables crops  to resist pest using natural mechanism e.g. goose neck sorghum  against birds ,tiltering  sorghum against  shoot fly
• field/farm hygiene-keep the  field free  from  any plant material harboring  pests by rouging ,removal  of crop residues
• Alteration of environmental conditions by creating microclimates that are not conducive to some pests e.g. open pruning, mulching for  traps
• Destruction of alternative host especially weeds that host pests e.g. Removal of mallow weeds help control cotton strainers. Use of clean planting material e.g. seeds, suckers, crown bananas weevils are  controlled
• Proper  spacing-makes it  difficult for pests to move  from one  plant  to another  through close spacing in  ground  nuts  controls aphids
• Using  organic  manure  which  discourages  eelworms
• Irrigation-overhead  irrigation in  cabbages controls aphids(any 10×2 must  be  discussed)

3. What does the term close season mean in crop production?

            – A period during when a particular crop is not supposed to grown in a given areas so as to

control   diseases and pests built up.

4. – Use of clean planting materials.

            – Timely planting.

            – Proper seed bed preparation.

            – Use of resistant crop varieties.

            – Proper weed control/ destruction of alternate host.

            – Observing field hygiene.

            – Mulching.

            – Use of  close season.

            – Use of trap crops.

            – Proper spacing.

            – Timely harvesting.

            – Use of crop rotation.                                                                                    

6. Four symptoms of viral infections in plants

               – Leaf curling

– Mosaics

– Malformation/distortions

– resetting (short internodes)

– Leaf chlorosis

        (a)        B – American bollworm ½mk

            C – Weaver bird ½mk

            D – Mongoose bird     ½mk

            (b)- Flooding with water

• – Fumigation of the soil with furadan
• – Physical killing ( ½ x1 = ½mk)

            (c)    Fruits      ( ½ x 1 = ½mk)

8. (b) The various practices carried out in the field to help control crop diseases                    

• Crop rotation
• Rugueing/destroy infected plants
• Plant disease-free plant/use certified seeds
• Closed season
• Early planting /timely planting
• Proper spacing
• Timely weed control
• Use of resistant varieties
• Application of appropriate chemicals
• Use of clean equipment
• Quarantine
• Heat treatment to kill pathogens
• Pruning to create unfavorable micro-climate for diseases

–     Proper nutrition to prevent deficiency

9. – Some pesticides cause suffocation of pests by blocking respiratory surfaces

• Some pesticides are stomach poisons that kill pests by damaging the cells/ tissues
• Some pesticides damage the pests nervous system

–    Some pesticides kill pests by destroying digestive system    

10. a) Cutworm
11. b) – Cuts the stem causing lodging

          – Reduce plant population                                                                                                        

1.  c) – Use of appropriate insecticides

Removing and killing it         

11. i) This is a situation in which pest population caused damage beyond tolerance
12. ii) This is the use of combination of both chemical and cultural pest control methods
13. four harmful effects of crop pests                          

• Some e.g. nematodes  damage crop roots  causing wilting and death of the plant
• Some like squeals unearth planted seeds leading to low plant population some destroy crop leaves lowering photosynthetic area-result to reduced yield
• Sucking pest deprive plants  of  food by  sucking plants sap
• Some pests attack fruits  berries  and  flowers lowering  their quality and quantity
• Some pests destroy embryo seeds lowering  their germination potential
• Some transmit crop diseases
• Some e.g. stalk borer eat the growing points causing retarded growth
• They lower mansetabills of crops produce  by lowing quality
• Where the leaf is the major product pest  damage lower the  quality and  quantity  through defoliation

13. a)Potato blight
14. b) (i) Pythophthora infestants
15. ii) dry patches i.e. necrotic lessiory on leaves and fruits

• affected fruits appear rotten and fall off prematurely

1. c) spraying with copper fungicides

• rogueing the affected crop

14. (a) – Anthracnose of Bananas / Banane anthrancnose;(1×1=1mk)            

(b) – Spray with (appropriate) fungicide

– Plant resistant varieties        

15. a)- Mouse bird
16. b) – Destroys grains in records

                        – Destroys fruits e.g. tomatoes

16.

• Cause swellings called galls on the roots.
• Leads to blockage of the vascular vessels which transport materials within plants leading to wilting and stunting growth of the crops.

17. four cultural practices used in controlling crop pests

• Timely planting
• Proper tillage
• Close season
• Trap  cropping
• Timely harvesting
• Crop rotation
• Planting resistant  varieties

Field  hygiene

18. three symptoms of coffee berry disease.

• Fungal disease
• Favoured by high rainfall
• Flowers have dark brown blotch /stred on brown petals
• Green servier have small dark sunken parches/lessions
• Barry (dip in the ground/dry up on the  in the black mummified condition and when squeezed they are empty

19. (a) M – hedgehog N- Squirrel      P – Rat

             (b) M – Use dogs

            N- eat germinating maize/bean seedling

21. – timely planting

• Early planting
• Timely harvesting
• Early harvesting
• Proper tillage
• Close season- period when that crop is not grown anywhere trap cropping
• Crop rotation
• Planting resistant carieties
• Field hygiene
• Alteration of environmental
• Crop nutrition
• Destroying alternative host
• Use of clean planting material
• Proper spacing
• Lose of organic manure
• Irrigation.