Unit 3 Crop Protection

Question 1

Describe 3 things can reduce crop productivity?

Answer 1

• weeds
• invertebrate pests
• disease

Question 2

How to weeds reduce crop productivity?

Answer 2

Weeds are a problem due to competition

They compete for light, water, soil nutrients and space

Question 3

How do invertebrate pests reduce crop productivity?

Answer 3

Invertebrate pests such as nematodes,molluscs and insects

They damage leaves of roots and can act as parasites or disease vectors

Question 4

Name 3 pests and the type of pesticide that can be used on them?

Answer 4

Insects- insecticide
Molluscs- molluscicide
Nematodes-nematocide

Question 5

What 3 pathogens cause plant disease?

Answer 5

Fungi
Bacteria
Virus’

Question 6

Give three ways that pathogens can spread from plant to plant:

Answer 6

Soil borne
Air borne
Insect vectors

Question 7

What is the main type of pesticides used against plant diseases?

Answer 7

Fungicides

Question 8

Why do fungicides often have to be reapplied?

Answer 8

Due to rain washing it off and leaving the plant unprotected

Question 9

How do farmers know when it is best to supply these pesticides to crops to combat diseases such as Patrao blight?

Answer 9

By using techniques such as the smith period or by using weather forecasting

Question 10

Properties of annual weeds:

Answer 10

Grow very quickly
Rapidly produce flowers as short life
Produce large numbers of seeds
Seeds can live gears under ground before needing to grow

Question 11

Properties of perennial weeds:

Answer 11

Already established in the habitat
Have storage organs
Are able to reproduce veagativley

Question 12

3 examples or cultural control:

Answer 12

Crop rotation
Ploughing
Early weed removal

Question 13

Why is crop rotation good?

Answer 13

As it limits the effects of soil inhibiting pests by changing the crop type

Question 14

Why is ploughing good?

Answer 14

As it burries and destroys perennial weeds

Question 15

Why is early weed removal good?

Answer 15

Allows crops to grow bigger and tolerate competition

Question 16

What type of pesticide is used on weeds?

Answer 16

Herbicide

Question 17

What type of plants do selective herbicides have a greater effect on?

Answer 17

Broad leaved plants

Question 18

What is the difference between contact and systemic herbicide?

Answer 18

Systemic herbicides are absorbed and transported through the plant’s vascular system, killing the entire plant.

Contact herbicides kill the part of the plant in contact with the chemical but the roots may survive and the plant may regrow.

Question 19

What does biological control involve?

Answer 19

Reduction of a pest population by deliberate introduction of its natural enemy

Question 20

What’s 3 risks associated with biological control?

Answer 20

It may become and invasive species
It may prey on other species
It may infect other species

Question 21

What is intergrated pest management (IPM)?

Answer 21

Combination of techniques including chemical control
cultural control
biological control
as well as host plant resistance

Question 22

List three problems with chemical control:

Answer 22

Chemicals are not short lived
Chemical resistance
Not specific

Question 23

What is bioaccumulation?

Answer 23

Bioaccumulation is the buildup of chemicals per animal

Question 24

What is biomagnification?

Answer 24

The increase of concentration of a chemical between trophic levels