Monitoring prevents damage from corn leafhoppers in RS

In Rio Grande do Sul, a joint action between Emater/RS and the Cooperative Technical Network (RTC) will begin to monitor the presence of corn leafhopper (Dalbulus maidis) in crops. The work will take place in 50 municipalities in Rio Grande do Sul, where technicians from the institution will visit rural properties weekly to replace traps and count the insects captured. The data collected will be sent to the RTC, which will be responsible for consolidating the information and creating a statewide map of occurrence. 

This is a unique collaboration between Emater/RS and the RTC. Previously, monitoring initiatives were conducted separately by cooperatives linked to the network or by extension workers. 

Monitoring and management are essential

The corn leafhopper is a relatively new pest in Rio Grande do Sul. As explained by Emater/RS rural agricultural extension agent Elder Dal Prá, records began in the 2020 and 2021 corn harvests. 

"The insect transmits pathogens responsible for a disease known as stunting, caused by two bacteria, as well as another disease caused by a virus. These diseases are uncontrollable and can compromise crop productivity," he warns. 

Elder also emphasizes that not all leafhoppers are infected. "For this to occur, the insect must first feed on an already infected plant. For this reason, leafhopper samples will be collected at specific locations in the state and sent to specialized laboratories, where molecular tests will be performed. These tests allow us to identify the presence of bacteria and viruses associated with leafhopper disease," he explains. 

Characteristics and identification in the field

The corn leafhopper's cycle takes approximately 45 days under favorable temperature conditions. The eggs are laid in the leaf blade. The nymphs are straw-colored with dark spots on the abdomen. The adults are about four millimeters long, light-colored, and have black spots on their heads, which is the main characteristic for field identification.

The insects live in colonies in the cartridge and young leaves of the corn and the management of the leafhopper is done in an integrated manner, with the adoption of different practices, such as the elimination of volunteer corn/tigera, constant monitoring of the presence of insects and diseased plants, use of less susceptible cultivars, sowing in a single season, treatment of seeds with insecticides and application of insecticides according to the incidence of the pest.

Monitoring generates security

For Jesus Amilton Amaral, a corn farmer from Lindolfo Collor, monitoring is an essential prevention tool. "I believe this trap will be very helpful, indicating whether the pest is present or not, and with this monitoring, we can act before the problem worsens. It provides the security to continue producing, even in the face of difficulties," he says. 

With the union between Emater/RS and the Cooperative Technical Network, the expectation is to strengthen the information network and provide farmers with increasingly precise guidance for managing the corn leafhopper, contributing to the protection and sustainability of corn production in Rio Grande do Sul.