Pest & Diseases Flashcards
What is cultural control?
Cultural control is preventative practices and managing the environment to minimise plant problems. Is applicable to pests, disease and weeds.
What is biological control?
Biological control just applies to pests in this syllabus. It is using a natural predator to seek and destroy the pest.
List some cultural control techniques in a greenhouse?
Good hygiene to remove overwintering p+d Quarantine new plant additions. Correct watering techniques. Correct containers. Managing the growing environment well - right amount of heat, light, water, nutrient, moisture, ventilation. Space plants correctly. Crop rotation Resistant varieties. Prune out infected material Hand removal of pests.
Vine weevil (PEST) – Cultural control
- Check under pots and staging to find adults in the daytime (they are nocturnal)
- Trap adults with sticky barriers on staging
- For crops that are particularly susceptible monitor the plants closely (Cyclamen)
Glasshouse Whitefly (PEST) – Cultural control
- Inspect new plants for presence of pest
- Hang yellow sticky sheets to trap flies
- Clean greenhouse in Winter to remove overwintering whitefly
- Remove weeds (alternative Host)
Damping Off Disease (DISEASE when sowing seeds) – Cultural control
- Use tap water for watering seeds
- Don’t overcrowd seeds
- Adequate ventilation and spacing of seeds
- Don’t over water
Grey Mould Botrytis (Disease) – Cultural control
Can affect many different plants in the greenhouse –TOMATOES, POINSETTIA
• If you see it remove and dispose of infected material asap
• Don’t water leaves, water roots
• Water first thing in morning to allow excess water to dissipate
• Make sure it is well ventilated
• Do not overcrowd plants
What is biological control?
Biological control is introducing a natural predator to kill the pest. Like ladybirds eating aphids in the garden. Biological control in a protected environment is feasible because it is a closed environment and predators cannot escape.
What is the biological control for vine weevil?
Vine weevil adults hide under pots in the day time, and eat notches out of the plant leaves. Their larvae eat through roots of plant and will kill them.
Microscopic nematode watered onto compost. Enter larvae and release deadly bacteria.
What is the biological control for white fly?
White fly suck on sap from leaves, and excrete honeydew. Cause leaves to brown and die, and can stunt growth of plant or if a bad attack can kill.
Parasitic wasp lays eggs in whitefly.
What is the biological control for 2 spotted spider mite or red spider mite?
Red spider mite feeds on sap from leaves. Mottling of leaves, and they can travel from plant to plant.
A predatory mite can be used which will eat it.
What is the biological control for aphids?
Aphids feed on sap excreting honey dew. Cause stunted growth, leaves to die and even plant death.
Parasitic wasp lays eggs inside aphid.
What is biological control for slugs?
Slugs eat everything!
A mircroscopic nematode will enter the slug and release a deadly bacteria.
Pros and Cons of biological control?
Predator will seek and destroy.
Some of them require a certain temperature/time of year to work.
Not damaging to environment.
Not poisonous to humans.
Avoids build up of chemical residue in crops.
Need to make sure they don’t escape.
Have to be used immediately on delivery.
Skilled work - need to be knowledgeable about your pests life cycle and optimum time to use.
Pros and cons of chemical control?
Acts immediately and can be applied any time.
Can be stored and used as required.
Kills other beneficial insects.
Risk of poisoning to humans.
Chemicals have to be stored safely.
Number of pesticides available is reducing.
Bad for the environment.
