How Brazil became the largest producer and consumer of biocontrol products

Three possible reasons for Brazil to emerge as the largest producer and user of biocontrol agents in the world are the cultivated area, the constant occupation of these cultivated areas and also the climatic conditions. Brazil's agricultural production plays a fundamental role in global food security, as can be seen by its substantial production. In 2021/2022, Brazil produced 127 million tons of soybeans (≅ 38% of world production) on ≅ 42 million hectares; 656 million tons of sugar cane (≅ 40% of world production) on ≅ 9 million ha; 50 million bags (60 kg each bag) of coffee (≅ 33% of world production) on 1,9 million ha; 116,5 million tons of corn (≅ 11% of world production) on 22 million hectares, among other important food crops, feed, fiber and fuels (Agrianual, 2022). The production of all these crops is highly dependent on both climatic conditions and the control of plant diseases, pests and weeds.

Furthermore, the country's long history of biocontrol under field conditions is another important aspect. The use of the fungus Metarhizium anisopliae to control leafhoppers in sugarcane and weak strains of citrus sadness virus to control this disease in the 1960s, and Baculovirus to control soybean caterpillars in the 1970s, are important examples. In the same decade, control of the sugarcane borer through the use of the wasp Cotesia flavipes became a standard management strategy throughout the country. The success of these research-driven biocontrol strategies stimulated investments in studies of both pest and plant disease biocontrol in the following decades. However, the same success has not been achieved with weed biocontrol.

For many years, due to the lack of strong competition with chemical pesticides and the lack of interest from large companies, biological products were mostly produced by farmers themselves or sold without registration. However, this scenario changed in the early 2000s, when biological product companies were pressured to register their products under pesticide legislation. Furthermore, a new method of registering biological products was created at the beginning of this century: the registration of products for use in organic agriculture. Using this method, registered strains can be explored, upon authorization, by several companies, facilitating the registration process, making it simpler, faster and more economical. With the growth of the biological products market and the problems observed with the use of pesticides, legislation was changed to prioritize the registration of biological products. Another important improvement in legislation was the registration of biologicals by target, and not by culture, as is the case with pesticides. This regulatory improvement encouraged the registration and adoption of biologicals.

Brazil validated the guidelines for tropical agriculture and became the largest supplier of the most important commodities (coffee, soybeans, sugar cane, oranges and many others). These commodities are produced year-round, with two or even three harvests per year, which can initially be seen as a competitive advantage. However, the concept of “hibernating plague or biological void” does not apply to us. Although the tropical climate favors plant growth, it also allows the pathogen and plants to multiply throughout the year. With a limited number of chemical molecules and resistant cultivars, the emergence of resistant pest populations is frequently reported. Therefore, biocontrol has emerged as the plausible strategy for integrated pest management (IPM) approaches.

According to Bueno et al. (2020), with data obtained in 2018, in a rough, incomplete and probably underestimated approximation of the use of biocontrol in Brazil, the area under biological control use was more than 33 million hectares. However, considering the rate of growth in recent years, the area under biological control in Brazil must be greater than 70 million hectares. The largest areas under biological control with bioproducts registered in 2022 were soybeans (20 million ha), corn (9,8 million ha), sugar cane (6,6 million ha), coffee (0,4 million ha), other crops (4,1 million ha) (Limberger, 2022-data from Spark). It is also important to note the number of biological products registered in Brazil, which increased from one registered in 2005 to 482 registered in February 2023. Currently, for each relevant plant disease, such as Asian soybean rust, of coffee plants and white mold, there is already at least one registered biocontrol product.

The most extraordinary market expansion for biological control has been for nematode management. Biocontrol has surpassed the chemical nematicides market and is today the largest biocontrol market in Brazil, representing, in 2022, 44% of bioagent sales. Considering nematode control, biological products represented, in the 2021/2022 harvest, 55%, 94% and 100% of the nematicides market sold for sugarcane, soybeans and corn, respectively (Limberger, 2022-data from Spark ). It is worth noting that, in most field trials, products based on bacteria, fungi or a combination of both outperformed chemical nematicide in reducing populations of most plant parasitic nematodes. Interestingly, this has resulted in not only the greatest expansion of biological control for nematodes, but also increased awareness of other plant diseases caused by soil-dwelling pathogens. Furthermore, some of the products registered for nematode control, particularly those that have an intrinsic root protection capacity, also protect against root infections caused by soil-borne fungi, such as those caused by Fusarium.

Currently, what would be the new frontier of biocontrol for the management of plant diseases? There is an increase in the use of biocontrol for foliar diseases such as Asian soybean rust (Phakopsora pachyrhizi) and coffee rust (Hemileia vastatrix). For these targets, all registered products are based on bacteria, mainly Bacillus, which expand the range of action of the chemical fungicide. Biofungicides are used in combination with chemical fungicides and it is important that biological products are compatible with the most commonly used pesticides and are sprayed early in the season, especially when induced resistance is the main mode of action. This combination results in higher yield and presumably reduces the selection pressure exerted by the exclusive use of systemic fungicides.

In the Brazilian market, 142 products based on Bacillus spp. (B. amyloliquefaciens, B. pumilus, B. subtilis and B. velezensis), Clonostachys rosea, Trichoderma spp. (T. afroharzianum, T. asperellum, T. harzianum, T. koningiopsis, T. reesei, T. stromaticum and T. viride) are registered as biofungicides; 17 based on B. subtilis are registered as biobactericides; and 96 based on B. amyloliquefacies, B. licheniformis, B. methylotrophicus, B. paralicheniformis, B. subtilis, B. velezensis, Paecilomyces lilacinus, Pasteuria nishizawae, Purpureocillium lilacinum, Trichoderma endophyticum e T. harzianum, among others, are registered as bionematicides.

263 plant-based products are registered as bioinsecticides. beauveria bassiana (95) Metarhikum anisopliae (91) Bacillus thuringiensis (44) baculovirus anticarsia (14) Isaria fusorosea (8) among others. Eighty-six products based on beauveria bassiana (76) and others (10) are registered as bioacaricides. Unlike biofungicides and bionematicides, practically 80% of bioinsecticides and bioacaricides are based on an isolate of M. anisopliae IBCB 425 and in an isolate of B. bassiana IBCB 66. The trend in the Brazilian market is to register formulated bioproducts that contain a mixture of species of microorganisms or even mixtures of multiple strains of the same species (Agrofit, 2023).

Although there has been a large increase in the number of registrations of products for biocontrol, called biopesticides or bioprotectors, this does not represent the reality of adoption by producers, as there has been an increase in the adoption of on-farm or homemade production, that is, companies that establish industries on their farms to produce the biocontrol agents they need. There are different levels of this industrial production, from artisanal (such as biofertilizer production) to industrial production (similar to those that have biologicals as their main business). Such initiatives resulted in the creation of several biological products industries in the country. Although there is controversy as to whether such a production system will be adopted more than registered commercial products, we all agree that this lower-cost biocontrol initiative has spread the benefits of adopting biocontrol in IPM across the country. However, there are reports of producers who have discontinued their own on-farm or home production to adopt commercial bioproducts available on the market.

What do we urgently need to do so that biological control continues to grow in Brazil?

1. Develop bioherbicides;

2. Control Asian soybean rust and coffee leaf rust, as well as powdery mildew in various crops exclusively with biological control agents and, eventually, in combination with other ecological approaches, such as resistant cultivars and crop management practices;

3. Select new biocontrol agents adapted to the tropical climate, as well as adapted and capable of dealing with climate change;

4. Train those involved in production chains in biological control.

By Wagner Bettiol (Embrapa Environment) and Flávio H.V. de Medeiros (Federal University of Lavras)