There are real alternatives to widespread pesticide use, Australia must embrace the change

By Sarina Macfadyen and Nancy Schellhorn

Australian farmers are heavily reliant on the use of pesticides to control weeds, diseases, and insect pests, collectively known as agripests.

In some industries, pesticides are the first option when managing pests, rather than a last resort. They are not only applied as aerial sprays after a pest has been detected but are coated on seeds and soil as a ‘just-in-case’ application, well before any outbreak is detected.

And the trend is becoming worse. Data on pesticide use is patchy, but national pesticide sales of herbicides have increased 34%, insecticides 22% and fungicides 49% (2013/14 to 2020/21) and use per dollar-value of our agricultural production has increased 67% over the last 30 years. At the same time, other OECD countries have removed some pesticides from use and are trying to re-structure their farming systems to accommodate the loss.

Australia has been slow to recognise the magnitude of the required shift away from pesticides and the challenge it poses for food production. Some of the countries that Australia exports to have identified active ingredients they no longer want on products they buy from us. For example, canola growers will have to stop using omethoate to control red-legged earth mites if they want to continue selling into the European market. Australia, which prides itself on being a good global trade partner, is finding it needs to meet emerging expectations on chemical use set by our trading partners.

The Australian agri-food sector can become leaders for change in this area. But vision and commitment is needed from all sectors to bring about change in the way we manage pests and communicate this shift to our trading partners.

How did we get here?

The widespread use of pesticides has a legacy of success in reducing crop loss and food waste and is simple to implement. The active ingredients in pesticide products today are relatively cheap, easy to apply, quickly kill a large range of pests and are profitable for agricultural chemical manufacturer and distributors. Yet, the rate of discovery of new active ingredients has slowed considerably. At the same time, pests are developing resistance at an accelerating rate, leaving certain products ineffective. CSIRO has been taking steps to overcome the agripest challenge and has been identifying reasons why the adoption of alternative and diverse pest-management practices has stalled in many agricultural industries.

Incremental change is happening

Replacement of the old generation of pesticides with a new suite of technology-based and ecological-based solutions to managing pests is an ongoing process. The resistance used to be ‘it’s not economical’. Now, viable alternatives to pesticides are available from companies who are reimagining how farming and food systems can work.

One area of change is the replacement of simplified and synthetic active ingredients with more complex biopesticides (that are often more specific and therefore less harmful to non-targeted species). Biopesticides require a shift in mindset and behaviour of producers. They take more time than chemicals to kill pest species (as the fungal, bacterial, or viral pathogen must invade the host and make them sick) and farmers need to factor this delay into production.

In the meantime, using pesticides more efficiently and site-specifically is becoming easier. Some farmers are investing in optical spot sprayers and autonomous robots, which can target herbicide application only on green plant material. This means that herbicides are applied over a much smaller geographic area. One company, SwarmFarm Robotic Agriculture, aims to remove the risk of spray drift by only spraying when it is safe to do so.

The move to targeted application is also needed. Digital crop protection can tell producers the insect pest threat in their region and where pests are on their property - information delivered in real-time to their smart phone. This can shift behaviour away from ‘just-in-case’ insurance sprays.

These techniques go a long way to conserving biodiversity on farms, particularly beneficial insects (such as bees, lady beetles, spiders, and lacewings) that deliver ecosystem services of pollination and pest control. Overseas, the practice of releasing factory-raised sterile insects to disrupt the mating process of pest species is also having some success.

We can’t afford to wait for the market

Reimagining entirely new approaches to our food system and unlocking barriers to change will eventually overtake the pesticide-based systems we rely upon today. This change will happen in combination with sophisticated digital platforms that enable recording of farm practices in a site-specific manner to generate evidence of change. Essential to success is the ability to share this information safely and robustly with people in the value chains, and will require commitment from a diversity of stakeholders.

Over the last two years CSIRO has been convening conversations within Australia’s agri-food system to build this commitment to responding to the agripest challenge. To remain competitive, Australian farmers cannot rely solely on their hard-earned reputation; they will need to substantiate their claims.

Albert Einstein said of inertia that ″nothing happens until something moves″. Rather than waiting for pest resistance or market forces to further reduce our reliance on pesticides, Australian farmers must be the ones moving. However, they will not be able to achieve significant change alone. Backing from regulatory bodies, research providers, cross-industry alliances, venture investors and startups is needed to make sure change on farms is supported and communicated to our global agri-food partners.