Corn leafhopper pest costs Brazil USD 6.5B in annual farm losses
The biggest nightmare for Brazil’s corn producers – a pest known as the corn leafhopper – causes an estimated annual loss of USD 6.5 billion.
Over the four harvest seasons from 2020 to 2024, losses caused by the insect in crops reached USD 25.8 billion.
The impact reflects an average production loss of 22.7 percent from 2020 to 2024 – equivalent to about 31.8 million tons of corn per year. About 2 billion 60-kilogram bags of corn were not produced.
Furthermore, the cost of applying insecticides to fight the Dalbulus maidis surged by 19 percent during the period, exceeding USD 9 per hectare.
The estimates are part of a study released this week by the Brazilian Agricultural Research Corporation (Embrapa), linked to the Ministry of Agriculture.
Scientific journal
The study was published in the April issue of the international scientific journal Crop Protection.
Based on data from 1976 onwards, the specialists calculated the damage stemming from corn stunt disease, caused by bacteria transmitted by the corn leafhopper.
The pest is described as “the greatest health challenge facing Brazil’s corn production system in recent decades.”
The survey was conducted in 34 municipalities in the country’s main producing regions.
Embrapa researcher Charles Oliveira points out that “in about 80 percent of the locations covered, the leafhopper or the resulting stunting were identified as the primary factor behind the drop in productivity.”
The pest
The corn leafhopper acquires the pathogens that cause corn stunting by feeding on infected corn plants and then transmits them to healthy plants.
In addition to affecting grain yield, the disease manifests in corn in two ways – it alters the plant’s color and causes streaking.
Oliveira notes there is no preventive treatment against the stunting, which can lead to total crop loss.
He further says that the disease has been known since the 1970s, but the epidemic outbreaks were not frequent until 2015.
“Changes in the production system over the past few decades, such as the expansion of the little crop [second corn crop in the same agricultural year] and the cultivation of corn throughout most of the year have created a favorable environment for the survival of the leafhopper and microorganisms,” he reported.
A champion under threat
Brazil is the world’s third-largest corn producer and one of the leading exporters. As per official figures, the 2025–2026 harvest is estimated to yield 138.4 million tons, with a production value of some USD 30 billion.
Technical advisor Tiago Pereira, who also participated in the study, points out that the pest represents “losses that directly impact producers’ income, production stability, and the country’s competitiveness.”
Researcher Maria Cristina Canale notes that the damage is not limited to the farm gates.
“Since corn is the basis for animal protein production (poultry, pork, and milk) and biofuels, crop failures drive up consumer prices and affect Brazil’s balance of trade,” she said.
In her view, studies that measure these losses are useful for “informing the allocation of financial resources, guiding the agricultural insurance sector, defining planting windows, planning strategies to mitigate damage, and evaluating the effectiveness of the practices adopted.”
Crop care
Considering the high reproductive and dispersal capacity of the corn leafhopper as well as the absence of preventive treatment, Embrapa has compiled a list of recommendations that can minimize the pest’s impact.
Among the suggested precautions are:
- Elimination of volunteer corn (plants that emerge between crops due to grain loss during harvest and transport) – breaks the life cycle of both the vector and the pathogen.
- Synchronization of planting – avoids long sowing windows that favor the spread of leafhoppers between fields.
- Use of resistant or tolerant cultivars – maintains high levels of productivity even under disease pressure.
- Early management with chemical and biological control applications in the early stages of plant growth – prevents the infection from causing more severe damage.
- Monitoring – involves constant and coordinated surveillance among neighboring producers.
There is also an effort to use biological control with entomopathogenic fungi, natural enemies of the pest, since some corn leafhopper populations have developed resistance to certain insecticides.
