Controlling pests with minimal use of pesticides was the focus of an industry seminar presented to arable farmers by Australian entomologist Paul Horne in Ashburton.
Organised by the Foundation for Arable Research (FAR), the seminars, with the focus on integrated pest management (IPM), were replicated in Gore and Timaru
Horne established Melbourne-based IPM Technologies more than 20 years ago to help farmers get better value out of fewer insecticides and improve control of insect pests by using IPM.
Specialising in facilitating adoption of IPM using a participatory approach, Horne has developed and implemented practical IPM strategies to manage invertebrate pests in a wide range of both protected and outdoor crops, including cut flowers, berries, vegetables, tree and vine crops, nurseries, broad-acre crops and pastures.
“We have worked on a wide range of projects across Australia and overseas with clients including small and large farming operations, R&D corporations, Australian and multinational chemical companies, agronomy companies, landcare groups and catchment management authorities.
“We help farmers and decision makers to control pests with minimal use of pesticides working across a whole range of different crops.”
IPM is the successful integration of all available methods of controlling pests, rather than just relying on pesticides.
An IPM strategy deals with all pests, harnessing biological and cultural controls as the first line of defence and using compatible chemicals, those that are least disruptive to the key biocontrol agents, as a support tool only when necessary.
Cultural controls are any management methods that either enhance populations of beneficial species or disrupt populations of pest species.
“In some cases cultural controls can be the most effective control of all and eliminate the need for pesticides all together,” Horne said.
Some examples of cultural controls are variety selection, time of planting, weed control, crop rotation and irrigation.
“The list of options for IPM is endless and is often determined by the individual requirements and possibilities on each farm.”
Chemical control in an IPM system means that the choice of which pesticide to use is not only based on the efficacy on the pest but also on the impact the product might have on beneficial species.
“There are many selective pesticides available but that does not mean that they are all safe to all beneficial species.
“It is important to understand the impact that each product will have on the key beneficial species for each crop type.”
The aim of IPM is not to eliminate all pesticide use, but to use pesticides as support tools for when biological and cultural controls are not enough on their own.
Some pesticides are not synthetic chemicals and include bacterial, viral and fungal pathogens that are formulated to be sprayed in the same way as chemical insecticides.
“The aim of monitoring is to decide if a crop needs a pesticide application or not, and if so, which one.”
For IPM crop monitoring this involves looking for both pest and beneficial species.
Horne said the best way to do this is by direct searching and using a hand lens.
Pheromone traps and sticky traps can also be useful tools.
The frequency and intensity of monitoring is determined by many factors including time of year, pest pressure, value of the crop and the needs of each farm.
“It is important that the monitoring programme is simple, practical and achievable. It is better to a do a little bit often than none at all.”
Horne emphasised IPM is about accepting all three; pesticides, cultural control and biological.
