Australian Truffle Pest & Disease Newsletter

Integrated Pest and Disease Management

Integrated Pest and Disease Management (IPDM) is a strategy that takes in account the whole crop ecosystem. Pest management decisions are based on economic thresholds using one or several of all appropriate pest management tools available while minimising the hazard to people and the environment.

Two people monitoring for slugs and slaters in a truffle orchard
Stewart Learmonth and Helen Collie using tiles to monitoring for slugs and slaters

IPDM is not one simple control measure but rather a process. The details of the process varies from crop to crop and region to region. The key aspects to any IPDM program are as follows.

Understand – Learn about what pests, beneficials and neutrals may be in the crop in order to be able to identify them. Gain an understanding of the interactions between them and their lifecycles in order to make informed management decisions.

Prevent – Control practices can be put in place to exclude or discourage pests from becoming established in the crop.

Monitor – Find out what is in the crop, where in the crop it is, at what time of year they are present and how many there are.

Action Thresholds – Every pest in every crop situation will have a threshold below which control is not economically viable i.e. the cost of damage by the pest is lower than the cost of control. Thresholds also varies with individual and their own level of comfort with pest risk.

Control – When monitoring and action thresholds suggest management is needed choose a management technique that is least disruptive to other agents in the orchard system and has least impact on the environment. Control options can fall into one of the following categories.

  • Biological – this includes predators, parasites, pathogens and competitors that will kill or disadvantage the pest. They are often referred to as beneficials.
  • Cultural – this includes crop management practices such as weeding, pruning and irrigation control that reduce pest reproduction, dispersal and survival. There are also pre-plant cultural practices site as site selection and ground preparation that can help manage pests and diseases.
  • Mechanical/physical – these are controls that physically kill or exclude a pest and include things such as tillage, traps and plant guards.
  • Chemical – In IPM, chemical pesticides are not excluded but should be used selectively to have minimal impact on non-target organisms, the environment and people. They are often used in combination with other management options and in a targeted way. Note that there are currently no pesticides registered or permitted for use in truffle orchards in Australia

Evaluate – After taking action, assess and evaluate its effectiveness. Continued monitoring is often part of this.

a monitoring tile with slugs and other invertebrates under it
Orchard monitoring is a key step when following an integrated pest and disease management (IPDM) process. Using bathroom tiles and bran is an inexpensive and relatively quick way to monitor for the main invertebrate pests in truffle orchards.

How can this be applied in truffle orchards?

One of the keys of any integrated pest management program is monitoring. We’ve created a guide on orchard monitoring for the most commonly found invertebrates, including slugs and slaters.  The guide provides instructions on how to monitor using tiles and bran, example recording sheets that you can print off, as well as a printable colour field guide to the more common pests and beneficials found in truffle orchards.

This type of field monitoring can be conducted year round, because it is not just when the truffle are ripe that they are being eaten. It is useful to monitor regularly because pest numbers fluctuate. With regular monitoring and observations you can build up a really good picture of what pests are present and how abundant they are.

Whole of orchard monitoring also helps identify hotspots, which allows you to target your management to where it is needed.

There are also guides available with colour photos for recognising invertebrate pest damage at harvest and grading. Taking and recording data such as the percentage of damaged truffles, the type of damage or the amount of trim is a very useful tool to make comparisons across blocks and across seasons. And the monitoring and harvest observations also allow you to see the impact of any management you’ve done. Any management you do must be value for money to make it worthwhile, so it important to know if it really did reduce the number of pests and reduce the level of damage.

We are in the early stages of determining the best practices in pest prevention and control for truffle orchards but some strategies are:

  • If African black beetle (ABB) are known to cause damage to establishing trees in your region, one approach is when planting trees ensure there are no ABB in the planting hole and then sink the tree guard 5cm into the ground to prevent access to the plant by adults.
  • Reduce undue stress on trees to improve their resistance to disease, this includes timing an rate of irrigation.
  • Physically excluded free water and insects that cause rot and feeding damage by covering exposed truffles.
  • If slugs, slaters and/or millipedes are a problem reduce habitat favourability and food sources in the orchard by removing leaf litter and maintaining a clean orchard floor.
  • Because slaters are attracted to light, a light combined with a pitfall trap buried in the soil may provide some control. Such light traps have not been trialled on an orchard scale.

Next year an IPDM guide for truffle growers will become available, combining the information from current web publications produced by the truffle pest and disease project (list current web pages). Keep an eye out on the DPIRD website for this.