Key Area 3-Crop Protection Flashcards Preview

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

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

-competition from weeds


How do factors reduce yield?

Reduce productivity


What are annual weeds?

Weeds that complete their entire lifecycle in one year


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


What are perennial weeds?

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


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


What are pests?

Thy damage plants, usually invertebrates


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


Describe diseases:

Mainly carried by invertebrates
Microorganisms: fungi/bacteria/viruses


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



What is cultural control?

Using traditional farming methods to protect plants


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


What are herbicides, pesticides and fungicides?

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


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


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


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


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


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


What does pesticide resistance mean?

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


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


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


What is biological control?

When a predator species is introduced to eradicate pest species


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


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