Introduction to the concepts of IPM

Transcription

1 DEPARTMENT OF PRIMARY INDUSTRY AND FISHERIES Principles of Integrated Pest Management Deanna Chin and Brian Thistleton, Entomology, Diagnostic Services

2 What is a pest? Principles of IPM Introduction to the concepts of IPM

3 What is a pest? An organism is considered a pest if it threatens resources valued by people. Usually involves economic loss

4 What makes an insect a pest? In natural environments there is generally a balance between pests and natural enemies Diverse habitats with many species Competition between species Most insects have natural enemies

5 In agricultural environments insects are often in large enough numbers to be considered pests Monocultures allow insects to breed up to large populations Natural enemies maybe in low numbers due to lack of food for adults The application of pesticides may reduce the population of natural enemies leading to increases in pest populations

6 Pests often do not have the specific biological control agents (e.g. parasites and diseases) which occur in their areas of origin e.g. spiraling whitefly.

7 Integrated Pest Management (IPM) The management of pest populations using all relevant control practices in a complimentary manner, so that the pest will be maintained below the economic injury level and there is minimal adverse effects on the environment.

8 Key features of IPM Regular monitoring Combination of control methods Minimising harm to beneficials and the environment Decide whether treatment is necessary after assessing the pest populations

9 Important features of IPM Low pest numbers may be tolerated Determine pest threshold levels Provide beneficial insects with a refuge Chemical spray is the last resort Avoid blanket spraying the whole farm Healthy well managed trees are less prone to attack

10 IPM - What does it involve? Become familiar with pests and beneficials of each crop Correct identification is important Understanding life cycles and seasonal occurrences Monitor orchards regularly

11 Insect control options Cultural Orchard management practises that reduce pest levels or make the plant less susceptible to attack Biological Natural or introduced enemies of an insect Chemical Insecticides to control pest levels Insect growth regulators

12 Cultural control Pruning Tree architecture Dust control Windbreaks and refuges Crop health Weed control Hygiene Time of harvest

13 Biological control Predators Natural: lacewings, ladybirds, Assassin bugs, predatory caterpillar, praying mantises, spiders Purchased: lacewings, ladybirds, predatory mites Parasites e.g. parasitic wasps Pathogens e.g. bacteria, fungi, viruses

14 Biological control Naturally occurring Inundative Releases Increase levels of naturally occurring biological control agents e.g. Cryptolaemus montrouzeri Classical Biological Control Introduce parasite from overseas e.g. spiraling whitelfy Refuges for beneficials Non-sprayed shady trees and crops

15 Predatory mites Releasing predatory mites, (Persimilis and Typhlodromus) to control two spotted mite (Tetranychus)

16 Parasites e.g. Encarsia wasp parasite of spiraling whitefly

17 Pesticides Insecticide choice Persistent, broad spectrum insecticides reduce the population of beneficials Use biological and physical control where possible Choose more specific and less harmful insecticides e.g. Bacillus thuringiensis for flower caterpillars