The climate crisis is expected to significantly impact agriculture, with more severe, resistant, and harder-to-control plant diseases. An Embrapa study forecasts that by 2100, 46% of agricultural diseases in Brazil will worsen, directly affecting key crops like rice, corn, soybeans, coffee, sugar cane, vegetables, and fruits. Rising temperatures and changing rainfall patterns will promote the spread of fungi, viruses, and vectors, necessitating a restructuring of Brazil’s phytosanitary monitoring and control systems.
This projection comes from a comprehensive review of 304 pathosystems (pathogen-host plant pairs) across 32 major Brazilian crops. The study found that fungi are the most common pathogens, appearing in nearly 80% of the cases analyzed.
More Heat, More Diseases
Climate change will create conditions more favorable to pathogen spread. The study predicts a temperature increase of over 4.5°C in some Brazilian regions by the century’s end, unless urgent global actions are taken. For fungal diseases like anthracnose and powdery mildew, this scenario offers ideal conditions for growth. Additionally, changes in rainfall, with more intense dry or wet spells, will further disrupt disease dynamics, according to a press release.
“The prediction of diseases in a climate change scenario is a complex challenge that requires the continuity of research and implementation of new adaptation strategies,” says researcher Francislene Angelotti, from Embrapa Semiárido (PE). It also emphasizes the importance of investments to strengthen national phytosanitary systems and structures and promote scientific innovation to meet the challenges imposed by climate change.
Expanding Vectors
It’s not just fungi that pose a threat. Vector-borne diseases, caused by pests like aphids, mealybugs, thrips, whiteflies, and mites, are expected to grow in significance across Brazil. Embrapa Meio Ambiente (SP) researcher Wagner Bettiol explains that higher temperatures shorten the life cycle of these insects and increase their longevity, resulting in larger, more active populations throughout the year. This poses a heightened risk for crops such as potatoes, bananas, tomatoes, citrus, and corn, which are already vulnerable to these pests.
Impact on Agricultural Pesticides
Research indicates that climate change could reduce the effectiveness of agricultural pesticides, necessitating adjustments in phytosanitary control strategies. Changes in climate will alter the dynamics of fungicides in plants—how they are absorbed, transported, and degraded—while also triggering morphological and physiological changes in crops.
As a result, chemical treatments may become less effective or require more frequent applications, driving up costs and increasing environmental risks. This has already spurred the search for alternatives, particularly biological control agents like biopesticides.
Brazil’s Leadership in Biocontrol
Brazil is the world’s largest producer and consumer of biopesticides, with the largest agricultural area under biological control. The global market for biopesticides is expected to reach $19.49 billion by 2030, according to Research and Markets.
However, researchers warn that Brazil must accelerate the adaptation of bioagents to changing climatic conditions. “We urgently need to develop bioherbicides and biological products that enhance nitrogen use efficiency and reduce plant stress,” says Bettiol. He also advocates for advancing biological solutions to control strategic diseases such as Asian soybean rust and coffee rust, as well as selecting biocontrol agents suited to the new climate.
Monitoring and Coordinated Action
Experts suggest a combination of strategies to protect Brazilian agriculture, including risk analysis, prevention, adaptation, strengthening phytosanitary surveillance, boosting research investments, and fostering international cooperation. Short-term measures include diversifying cultivation systems, integrating various management technologies, utilizing biological agents, and adopting epidemic forecasting and alert models.
“Mescing these challenges requires effective public policies and a coordinated effort between farmers, scientists and governments to ensure food security and sustainability of the agricultural sector,” reinforces Angelotti. She highlights that adaptation to climate change in the countryside cannot depend only on farmers: an articulation between science, government and the productive sector is needed.
Phytosanitary Risk: A Strategic Concern for Brazil
The study highlights Brazil’s vast agricultural diversity, which spans a wide range of climates and includes both tropical and temperate crops. This diversity underscores the need for regional evaluations tailored to the dynamics of phytosanitary issues in different production areas and future climate scenarios.
Embrapa Meio Ambiente researcher Emília Hamada stresses the importance of studying the spatial and temporal distribution of pathogens in the context of climate change. She emphasizes that field-based experiments are essential to identify vulnerabilities and implement protective measures for agricultural systems.
According to Hamada, climate projections suggest that some regions of Brazil could see temperature increases of up to 4.5°C by 2100. These changes, along with shifts in rainfall patterns, will likely worsen the risk of fungal diseases, such as anthracnose and powdery mildew, depending on the region.
Identifying risk scenarios is critical to understanding how climate change will affect crop vulnerability. More scientific research is needed to prevent economic and environmental damage, Hamada concludes.
Science and Adaptation as Key Solutions
The Embrapa study makes it clear that climate change is already shaping the future of Brazilian agriculture. While the potential economic and environmental losses are significant, strategic planning, innovation, and coordinated action can transform this challenge into an opportunity to modernize Brazil’s plant defense systems.
The full study is available at this link.
