Biological insecticide shows 85% efficiency in control of corn leafhopper

Climatic conditions and the history from previous seasons indicate that the incidence of corn leafhopper could be high in the second crop of 2020-2021 in Brazil, the planting of which begins in January next year. 

Infestations in the summer harvest are usually reduced but increase when the leafhoppers multiply, to attack later. Therefore, now is the ideal time to plan insect control, preferably with integrated pest management.

According to a researcher at Embrapa Cerrados, Sergio Abud da Silva, several actions are needed to reduce the incidence of this pest and corn stunting disease, which it transmits, such as crop rotation, use of certified and treated seeds, the maintenance of sowing windows from 20 to 30 days, and the diversification of cultivars and application of insecticides, among others.

The biological insecticide Octane (Isaria fumosorosea) has been suggested for the management of corn leafhopper because it has a prolonged action in the field, with a good residual, with more chances of reaching migratory insects, besides not causing resistance in the pest. “The results are excellent, with up to 85% efficiency in the control of corn leafhoppers,” stated the Koppert Center-South sales manager, Rodrigo Rodrigues.

For da Silva, it was important to highlight the fact that the use of biological insecticides in combination with chemicals provides the immediate shock effect of chemical control and the residual control effect with the biological, expanding the managing of the insect-vector. “After the application of insecticides, monitoring should continue to prevent re-infestation of the area,” he advised.

According to the researcher, the scenario of internal and external demand for Brazilian cereal led Brazil to produce two and even three annual crops of the grain in several regions. “Whether cultivated or tiguera (voluntary), the constant presence of corn in the field creates an environment favorable to the increase of corn leafhopper populations and the complex of stunting diseases, which can cause a reduction of up to 100% in infected plants. In areas with a high incidence, damage to productivity can be over 70%,” da Silva explained.

Monitoring carried out by companies associated with CropLife Brasil, shows that the occurrence of stagnation and an increase in the population level of the corn leafhopper in several Brazilian states, mainly during the 2015-2016 harvest. The largest outbreaks were identified in regions of Bahia, Goiás, Minas Gerais, São Paulo, Mato Grosso do Sul and Paraná.

The original Portuguese version of this piece is from CULTIVAR.