3.3 Crop Protection Flashcards
Identify the three main biotic factors that reduce crop productivity
Weeds
Pests
Diseases
How do weeds have an effect on crops?
Reduce the yield of crops by increasing the amount of competition for crop
How do pests have an effect on crops?
Cause damages to leaves, reducing photosynthesis potential
How do diseases affect crops?
Plants metabolism is harmed by the pathogen
What are the two types of weeds?
Annual and Perennial
Describe the properties of an annual weed
<ul> <li>Short Life-cycle</li> <li>High number of seeds</li> <li>Sexual Reproduction</li> <li>Rapid Growth</li> </ul>
Describe the properties of a perennial weed
- Long lifecycle
- Vegetative Reproduction
- Storage Organs
What is the function of storage organs in perennial plants?
To act as a store of energy ready to help growth if conditions are not ideal
Give an example of an annual weed
Goosegrass
Knotweed
Give an example of a perennial weed
Buttercup
What are the three types of invertebrate pests for plants?
Molluscs
Insects
Nematode Worms
What are the three types of disease causing agents?
Fungi
Bacteria
Virus
How are plant diseases often carried?
Inverebrate Vectors
Describe ‘Cultural Methods’ of crop protection
Cultural methods are the non chemical, traditional, preventive way of controlling a pest/disease/weeds
Give an example of a cultural method of crop protection
Ploughing, Autumn Sowing, Crop Rotation
What is an advantage of a selective herbicide?
Able to target broad leaved plants only, and will not have an effect on a narrow leaved plants
What is an advantage of a systemic herbicide?
Will spread through whole plant, killing all parts of plant and preventing regeneration
What type of herbicide would you recommend for a perennial weed?
Systemic, so it kills the storage organ, preventing regrowth
What is ‘disease forecasting’
Predicting when diseases will arrive based on weather forecasts
Why is protective application based on disease forecasting more efficient than applying once crop infected?
- Fungal Infections spread very rapidly and so preventive methods must be used to prevent the infection occurring, which is protective application
What are the two types of pesticide?
Contact and Systemic
Describe a contact fungicide
Sprayed <strong>on</strong> crop
Preventive
Describe a systemic pesticide
A system pesticide is absorbed by plant which makes it poisonous to plants
Describe a disadvantage of chemical protection of crops
Bioaccumulation
Persistent
Toxic to Wildlife
What is bioaccumulation?
The gradual build up of a toxin in a food-chain
What is biological control?
Addition of natural predator, parasite or pathogen to control a pest population
State a disadvantage of biological control
May become Invasive, out-competing native species and reducing biodiversity
What is integrated pest management?
The combination of chemical and biological control to control a pest population
What is an advantage of integrated pest management?
Reduces quantity of chemicals used
Give an example of biological control
Parasitic wasps to control an aphid population
