Farming with Less Pesticides: The Role of Technology

This past week I participated in a forum discussing the ability to use less pesticides within pome and stone fruits. This event was sponsored by the European Union with the topic of “How to reduce pesticide use in farming by 50% by 2050.” I was asked to present a view based on my experience (PowerPoint attached). I found the forum interesting, and have many thoughts, but we’ll save them for another day. For now, I want to focus on the future role of technology within almond farming, and how it can help us reduce our pesticide needs and hopefully reduce operational expenses. This overview will be expanded as I continue to think about this issue.Discussing pesticide use is difficult. Managing risk associated with damage caused by the targeted organisms, the lack of knowledge regarding the different chemistries, as well as general operational challenges faced by many farmers to consistently produce a high-quality crop that is expected by consumers. In writing this article, I am assuming that consumer preferences will not change, and if anything, will become more stringent, as consumers want to know more about farm operations. This will increase the pressure for pesticide reductions while demanding lower prices.Technology will be key to meeting these challenges. We will need new techniques to manage weeds, insects, soil-borne diseases, and canopy and fruit diseases. These will include a variety of autonomous vehicles, new, reduced-risk, low active ingredient modes of action, increased biologicals, and some out-of-the-box ideas.Autonomous vehicles. The most obvious use for autonomous vehicles includes spray applications and mobile weed rogueing units. Most of these will utilize artificial intelligence algorithms to learn and then identify the problems at hand.  Autonomous spray rigs are coming online (GUSS Spray Technologies) and provide the ability to reduce pesticide use by increasing the effectiveness of the pesticides applied. This occurs through the ability to slow the spray rig to speeds ensuring optimal spray coverage, while reducing double-spraying of areas. The technology also allows for rate control and oversight to determine if any errors are occurring. Weed rogueing units will be of similar value. These machines could scout the under-canopy areas and use artificial intelligence to identify weeds and kill them through a variety of methods such as manual tillage, through spot spraying of herbicide, or other technology. This tool would also be useful for more effective irrigation management.New biological pesticides. Although I am not convinced that there will be any short-to-mid-term biological pesticide solutions for early springtime bloom and fruit diseases, this may be different for later season canopy diseases and hull-rot management. The use of Bacillus sp. or other bacteria may be able to reduce hull rot by competitive exclusion of the Rhizopus pathogen. Additionally, these bio-agents may be useful in preventing rust or Alternaria leaf spot, both of which effect leaves and future crop-loads. More research focusing on these timings may be beneficial to the industry.New pesticides. New classes of pesticides that are effective at lower active ingredient levels would be useful in reducing the amount of pesticide applied. These new chemistries may include synthetic pesticides, peptides, iRNA, or bacteriophages. Some of these technologies are being introduced to the market (e.g. peptides with Vestaron), while others are several years away from being released into an effective product. Developments within this area are often more readily adapted because they often fit into the current practices and equipment utilized by farmers.Advancements in autonomous aerial spraying. Very little is known about how little fungicide is needed to reduce foliar disease outbreaks. By increasing our knowledge of epidemiology of various foliar diseases, we can target-apply preventative measures. These strategies may include applying material at varying patterns (e.g. checkerboard), or containing areas showing initial signs of infection to reduce the movement of the pathogen across the orchard. With the advancements in aerial drone technology, these techniques are becoming more probable, and more likely to be introduced within the mid-term.Advance pathogen and insect population detection. Knowing the level of disease or insect infestation risk would be useful when developing a pest management strategy. These techniques, when paired with the proper epidemiological studies, could lead to more accurate chemical applications. Some good examples in this area have been developed within almonds (e.g. DSV model for Alternaria) and pistachios (e.g. BUDMON and ONFIT). Additionally, the use of new soil genetic tools (e.g. Trace Genomics) may be useful in determining overwinter pathogen loads of soil-transient plant diseases, such as rust and Alternaria.The further development of these tools will be required for farmers to manage the increasing challenges of emerging and invasive pests while reducing pesticides. Some may take decades to fully develop, and we need to work now to begin the discovery work. Additionally, these new tools must be partnered with good governance, meaning that barriers need to be reduced or managed by our government officials to improve innovation within these areas.Lastly, there are several tools that are present today, but aren’t widely used or available within almonds. These tools may provide an impact in the short-to-medium term and include:

• Additional artificial intelligence and weed identification technology integrated into current herbicide spray rigs. This would reduce herbicides applied and would allow substantial pesticide savings. This should be able to be integrated within a medium-term time frame;
• Auto-steer and speed control on spray rigs. This would reduce the variability in speeds that are often observed within canopy spray applications;
• Real-time insect population monitoring. There have been several breakthroughs in this area as “the internet of things” has advanced. Unfortunately, many still require weekly maintenance to maintain performance. This has led to reduced adoption of these tools.
• Early harvesting and crop drying methods. Shaking earlier can reduce insect infestation and hull-rot damage. Unfortunately, this is often offset with longer drying time or increased drying costs. Integration of drying methods may help reduce drying costs and time. Shaker technology will also have to improve to reduce damage to earlier harvested trees due to their susceptibility to shaker damage.
• Real time orchard health and harvest data. Knowing crop weights and tree health data may help identify problematic areas. This will lead to more targeted pesticide applications.
• Cover crops and removal of broad-spectrum insecticides. These techniques can increase beneficials which can suppress mite populations, reducing miticide applications.

When facing this challenge of less pesticides in farming, I am sure there are many ways to move forward. So, what are we missing? What can we be doing different to maximize our pesticide use efficiency?Please note that specific references to products are not endorsements, but rather examples of products within the marketplace.EIP Agri EU March 2022