IPM is best described as the use of multiple insect management strategies which minimise pest numbers while maximising both the economic and environmental sustainability of agricultural crops.
For over 50 years the main method of controlling insects in agriculture has been the use of insecticides.
There is no doubt that insecticides have increased producers’ ability to immediately manage insect pests and will continue to do so with each release of a new insecticide.
However, insecticide use alone should at best be seen as a short-term remedy and not a long-lasting solution.
History
For this reason, in 1959 a group of researchers published a paper titled, The Integrated Control Concept which discussed a pest management strategy that could reduce pest numbers while minimising pesticide usage.
They proposed that if pest outbreaks were only treated when it is economically beneficial, true long-term insect pest management could be achieved without insecticide resistance becoming an issue.
This concept has evolved into what is now known as Integrated Pest Management (IPM).
IPM is best described as the use of multiple insect management strategies, which minimise pest numbers while maximising both the economic and environmental sustainability of agricultural crops.
IPM can be divided into three broad categories: chemical, biological and cultural management practices (discussed in future articles).
Principles
Since the IPM concept was first proposed, many of its underlying principles have been adopted.
However, despite advances in ‘non-chemical’ insect management, the primary pest control method remains the use of insecticides, even within many IPM programs, rather than the use of cultural and biological methods, which aim to minimise the need for insecticide use.
Modern farming systems are generally intensive monocultures which can promote pest infestations by providing them with optimal food and shelter.
The main aim of IPM is to restore an ecological balance back into these farming systems. Long-term control is rarely totally solved by just treating the infestations with insecticides in a more environmentally friend way.
Re-establishing farming ecosystems can reduce the need to repeatedly apply insecticides season after season, thereby increasing profitability and reducing the environmental impact of agricultural pest management.
Poor uptake
IPM uptake in Australia has been poor. Reasons include the time required to implement successful IPM programs, and the cost of IPM friendly treatments.
This is despite the fact that once beneficial insect numbers rise to sufficient levels, the long-term financial savings can far outweigh the initial set-up costs; and despite the fact that the softer, and frequently more expensive IPM friendly treatments, are generally used at lower volumes than conventional spray applications and therefore are usually more cost effective.
A lack of IPM extension specialists may also be hampering adoption. This is often a result of funding cuts to state government primary industries (DPI); a general failure of university research; and private consultants not taking up the DPI’s prior role.
Furthermore, there is a trend toward free consultancy services by chemical supply companies—who have no obvious market advantage to implement IPM or assist growers in developing biological or cultural IPM methodologies which reduce the need for chemical controls.
Finally, there are no incentives or subsides to make the transition toward IPM attractive to growers. Government incentives have enabled growers overseas to not only establish successful IPM programs on farms, but also on an area-wide (local landscape) scale.
Benefits of area–wide strategies
Area–wide strategies have been successfully undertaken in Queensland citrus to control several scale species, and in American apple orchards to control codling moth.
In both cases large reductions in pest populations were observed.
Mating disruption of codling moth on an area-wide scale in American apple orchards resulted in reduced insecticide usage by up to 75% and led to increased profits of $210–$305/acre from a $125–$170/acre investment.
Implementation
The biggest issues in developing area-wide IPM strategies are of course how these strategies are implemented, who funds them and how they are monitored to maximise their effectiveness.
The answers to these questions can be found in the European Union and America where a combination of government funded strategies have been employed.
These have included free consultancy services from university extension agencies; government funding to farmers to encourage the uptake of IPM friendly technologies as observed with the USDA subsidised codling moth mating disruption programs; or other programs which provided financial benefits for employing IPM strategies such as improved ground cover management.
In Australia, both state and federal governments have been willing to invest in environmental development and restoration programs. Groups such as Landcare are already involved in environmental improvement of agricultural areas with funding available for erosion control and waterway improvement.
The adoption of many cultural IPM strategies can provide the same level of environmental benefit to local communities largely from reduced pesticide use and improved ground cover management.
But again, if this is to occur, increased governmental support is required. Organisations such as state DPIs—which have established links with industry and possess the skill base to aid the uptake of IPM of non-chemical pest management strategies—may help in this process.
The holistic nature of IPM attempts to address the causes of insect pest presence, not just the infestations themselves. This effectively reduces the need to repeatedly reapply costly insecticide applications year after year, there-by increasing the profitability of agricultural production and reducing their impact on the environment.
However, for IPM to be recognised as industry best practice, increased investment of both time and money is required to develop programs not just on a single farm basis but also on area-wide scales.
