Key Area 3-Crop Protection Flashcards Preview

Biology: Unit 3 > Key Area 3-Crop Protection > Flashcards

Flashcards in Key Area 3-Crop Protection Deck (24):
1

What are factors that can reduce a crop’s yield?

-pests
-diseases
-competition from weeds

2

How do factors reduce yield?

Reduce productivity

3

What are annual weeds?

Weeds that complete their entire lifecycle in one year

4

Give four features of annual weeds

-short life cycle
-rapid growth
-large quantities of seeds are produced
-seeds are viable for a long period of time

5

What are perennial weeds?

Plants that live for several years, becoming dormant in winter and growing again in the spring

6

Give two features of perennial weeds

They have storage organs for food for environments that don’t favour growth
They reproduce asexually using methods like runners: leads to rapid reproduction

7

What are pests?

Thy damage plants, usually invertebrates

8

What are the three groups of pests?

Nemotide worms: in the soil and attack the plants roots
Molluscs: snails/slugs destroy crops by eating leaves
Insects: damage plants by feeding on them

9

Describe diseases:

Mainly carried by invertebrates
Microorganisms: fungi/bacteria/viruses

10

What are three methods of control for weeds, pests and diseases?

Cultural
Biological
Chemical

11

What is cultural control?

Using traditional farming methods to protect plants

12

What are two methods of cultural control?

Ploughing-too layer of soil is turned over causing perennial weeds to be removed and buried, and decompose
Crop rotation-crops grown in a cycle in a field to break life cycle of pests specific to one crop

13

What are herbicides, pesticides and fungicides?

Chemicals sprayed to kill weeds(herbicides), pests(pesticides) and prevent growth of fungus(fungicides)

14

Describe the two types of herbicides and an advantage of each

Selective: only effect broad leaves plants~doesn’t affect any crops
Systemic: absorbed into transport system of plant~prevents regrowth of the weed

15

Describe the two types of pesticide

Contact: kill pests on the leave at time of spraying
Systemic: absorbed by the root and transported through the plant so any pests who tries to feed from the plant will be poisoned

16

Describe the two types of fungicides

Contact: prevents new fungus growth
Systemic: absorbed by the roots and transported through the plant to protect all part of the plant

17

Why are disease forecasts used when spraying fungicides?

Disease forecasts allow you to judge when to spray the fungicide based from when the optimal conditions are

18

What are four problems associated with plant protection chemicals?

-may be toxic to animal species
-can be persistent
-can accumulate in food chains
-can create resistant populations

19

What does pesticide resistance mean?

Chemicals in the pesticide do not break down and remain in the environment for a long period of time

20

What does magnification of pesticides in the food chain mean?

Organisms higher up the food chain consume more biomass and contain more fat so are found to contain more toxins

21

What does selection pressure mean?

When pesticides are sprayed onto a field it creates a selection pressure so only pests who are resistant to pesticides survive

22

What is biological control?

When a predator species is introduced to eradicate pest species

23

What are the risks of biological control?

Timing is crucial: if the species isn’t released at the time when the pest species is active it will be less effective
Controlled environment: species can escape if not released contained therefore controlled environments are better as the predator can not escape and conditions can be maintained as optimum

24

What is integrated pest management?

A combination of biological, cultural and chemical control methods are used with an emphasis on control, not eradication, of the pest