Kevin Chen, PhD, is CEO of Crop Enhancement, a venture-backed ag biotech startup based in San Jose, California. Here he writes about the different methods and technologies being introduced to reduce or eliminate the use of chemical pesticides in farming.
When it comes to what we eat, the demands of conscious consumers are clear: They expect ethically produced and sourced food that is healthy, safe and affordable. Many of those consumers would be surprised to hear that the move away from toxic pesticide use is not a new phenomenon. In the 1970s, partly in response to early coverage of the damaging environmental impact of pesticides, the USDA established a nationwide integrated pest management (IPM) program to spur innovative methods to solve pest problems. Fast forward to April 2018, and the European Union announced that it plans to “completely ban” outdoor use of neonicotinoids, a class of synthetic pesticides blamed for killing bees. Neonicotinoids are used in the field as well as in seed coatings for corn, soybean, canola, and other crops.
Some non-chemical approaches, such as pruning and crop rotation, have long been part of the sustainable cultural practices of many farmers. These approaches are now part of a larger IPM regime that increasingly offers sustainable solutions for industrial growers and small private farmers alike.
Many large companies, following suit, have been adapting to the environmentally friendly elements of IPM to meet consumer expectations for safe and ethically produced food. As an example, France-based Danone and US-based Mars Inc, two of the world’s largest food manufacturers, created an investment fund in 2015 called Livelihoods 3F. The fund will invest $140 million during the next decade to promote responsible farming practices and technologies consistent with IPM that use natural resources sustainably to enhance smallholder farm resilience.
Alongside some of the more established environmentally-sound methods of addressing the effects of pests, new and compelling solutions are beginning to emerge across the agtech landscape.
Reintroducing Natural Enemies to Pests
In the US, many insect pests were accidentally introduced from other parts of the world through migration of people and goods. For instance, the infamous Asian citrus psyllid (ACP), which is a looming threat to California’s $3-billion citrus industry, set foot in California when one person brought home a piece of a citrus plant from a trip to Asia. Upon arrival, such foreign bugs often lack natural enemies capable of controlling or suppressing their populations.
Introducing appropriate natural enemies sourced from a pest’s region of origin is one way to address this problem. Consumers who have bought ladybugs at home improvement stores to rid their gardens of aphids may already be familiar with this concept. Known as ‘beneficials’ in industry parlance, natural enemies in production agriculture work the same way, albeit on a much larger scale.
Scientists at Cal Poly Pomona recently won the prestigious IPM Achievement Award for developing a method of raising parasitic wasps to be a natural predator of the ACP. Entomologists believe the wasps will play a key role in reducing ACP populations, replacing far-reaching pesticide campaigns in sensitive urban areas.
Pheromones, which are naturally-occurring chemicals released biologically by bugs to signal their presence or make themselves known, can be used to disrupt insect mating behavior. One application of these non-toxic, biodegradable semiochemicals acts as a lure to trap insects, reducing their populations below the levels that can be economically damaging.
Pheromone sex traps have been used to kill the fall armyworm, which is currently one of the most challenging pests severely impacting major row crops around the world, using female-secreted pheromones to lure males. Once the males are ensnared in traps, there is no possibility of mating. Both lab and field tests have proven that traps baited with acetic acid capture significantly more male insects than control traps without the substance.
The downside of pheromone-release approaches is that they are currently quite expensive and require additional innovation and development to bring the costs down to a reasonable level. Pheromones can also be volatile, so they will require new delivery and formulation mechanisms. Aiming to solve these challenges is biotech startup Provivi that’s producing pheromones from inexpensive vegetable oil using biosynthesis and olefin metathesis.
Long-range Insect Repellents
Just as insect repellents work for humans at a summer picnic, they can also work in production agriculture. Insects rely on olfactory senses to detect food and mates, and they go out of their way to avoid plants that give off certain compounds.
Long-range natural insect repellents such as aromatic oils deter insects from feeding and laying eggs on treated plants. Many varieties of insects are turned off by Achillea fragrantissima, a type of desert plant with a powerful odor and an associated natural insect toxin. To that end, Israeli agtech firm EdenShield is developing a green pesticide alternative based on the extracts of this plant, which can be found in the Judaean Desert.
Short-range Insect Repellents
Neem oil – with the active ingredient azadirachtin – is one of the oldest insect-control products used to repel and disrupt a number of significant plant pests. This low-cost product is widely available in many forms and controls aphids, mealybugs, scale crawlers, mites, thrips and whiteflies. Agricultural oils are among the most widely used plant coatings. A pest that encounters a coating is deterred by its sensory properties, similar to the human use of bug spray, which repels biting insects. However, when overused or used incorrectly, oils can cause phytotoxicity and other side effects on plants. It is also worth pointing out that practical, wide-scale implementation of insect repellents is often compromised by the fact that it interferes with a plant’s natural functions including respiration and photosynthesis.
Scientifically Engineered Coatings
There is an emerging approach for effective and sustainable pest control that uses environmentally friendly materials innovations to deliver new modes of action (MOA) in the growers’ IPM toolkit. Designed using a combination of surface science and materials engineering expertise, farmers use these formulations to shield crops with a protective, non-toxic, microscopic film at the plant’s surfaces (leaves, fruit, and stems) protecting them from pest and disease damage. These solutions can deliver benefits including improved yields, reduced labor and equipment costs, reduced residual levels, improved resistance management, and improved worker and environmental safety.
Through materials design, for example, coatings can be tailored to offer growers the ability to cut back on the number of applications needed across a season, significantly reducing costs associated with labor and equipment. Case in point: cocoa producers today apply synthetic insecticides every two weeks, resulting in as many as 20 applications per year across two growing seasons. These new engineered coatings require growers to spray as few as four times per year – a 75% reduction in labor and equipment use.
As a result of this new wave of environmentally-effective approaches to pest management, investors and corporate players see significant opportunity for growth in the sector. According to AgFunder’s 2017 AgriFood Tech Investing Report, investment in ag biotechnology in 2017 saw some of the largest deals ever. And according to a Global Impact Investing Network survey, 63 percent of impact investors claimed they were putting dollars into food and agriculture. Impact investment in the sector has already grown at an annual rate of 32.5 percent since 2013.
Given this influx of innovation, interest and investment, the quest for sustainable solutions will likely lead to expanding options in agtech. Increasingly, new ideas and technologies offer better quality with more limited risks. Needless to say, these new products and methods will need to be assessed within specific crop systems, with success based on the quality and quantity of yields and the economic value to growers. For the consumer, though, it appears that hope is on the horizon.