Key Area 3

Question 1

What competes with crop plants and what damages crop plants

Answer 1

Weeds compete with crop plants, while other pests and diseases damage crop plants,
all reducing the crop yield or productivity.

Question 2

Why do weeds compete with crop plants

Answer 2

for resources such as light, nutrients, water and space thus reduces the growth and productivity of the crop

Question 3

Annual weed properties

Answer 3

Rapid growth, short lifecycle, high seed output and long term seed viability

Question 4

Perennial weed properties

Answer 4

Storage organs and vegetative (asxual) reproduction.

Question 5

What are invertebrate animals

Answer 5

pests of crop plants are invertebrate animals such as insects, nematode worms and molluscs.

Question 6

How is plant disease caused

Answer 6

by fungi, bacteria or viruses, which are often carried by invertebrates.

Question 7

What are cultural methods of crop protection

Answer 7

used to control weeds, other pests and diseases eg.
 Ploughing
 Weeding
sowing

Question 8

What are pesticides

Answer 8

Pesticides can be used to control weeds, pests and diseases.
 Herbicides are used to control weeds.
 Fungicides to control fungal diseases.
 Insecticides to kill pest insects.
 Molluscicide to kill mollusc pests.
 Nematicides to kill nematode pests.

Question 9

Pesticides can be selective or systemic. What do selective pesticides do?

Answer 9

control or suppresses the targeted weed species without affecting the growth of your crop.

Question 10

Pesticides can be selective or systemic. What do systemic pesticides do?

Answer 10

Systemic herbicides spreads through the vascular system of the plant and prevents regrowth.

Systemic insecticides, molluscicides and nematicides spread through the vascular system of plants and kill the pests feeding on the plants.

Question 11

Problems with pesticides

Answer 11

Toxicity to non target species.

once they have got into the environment they do
not degrade.

Bioaccumulation- build up of a chemical in an organism (usually from eating prey that contain the chemical).

Question 12

What is biomagnification.

Answer 12

Increase in contaminated substances or toxic chemicals taking place in the food chain

Question 13

What is Biological Control

Answer 13

where the control agent is a natural predator, parasite or pathogen of the pest.

-ensure that the control organisms does not become an invasive-

Question 14

What is Integrated Pest Management?

Answer 14

Where the pest is managed by a combination of biological, chemical and cultural control.