CropSolutions has work published in the magazine “Cultivar Grande Culturas”

The February edition of the magazine “Cultivar Grande Culturas” features the article “Alternatives for control”, produced by the CropSolutions research team. The work deals with the increase in soybean mealworm populations, demonstrating the need to use different management techniques and new studies on the pest.

The article “Alternatives for control” can be accessed here.

This pest causes a reduction in crop yield and hinders development due to the damage it can cause in the initial stages of the crop. And it has caused serious damage to many producers in the Center-West of Mato Grosso do Sul (MS), detected in the 2017/2018 harvest in the North of MS, in the regions of Coxim and Sonora. In the 2021/2022 harvest, the occurrence of this pest was high in many agricultural areas of MS, causing damage in the initial stages of the crop. And many areas were subjected to new replanting, delaying the harvest and causing economic losses to producers. In addition to MS, the high incidence of mealworms was found in areas in the South and East regions of Mato Grosso. In the current 22/23 harvest, it was observed that some regions that did not yet have so much incidence of this pest began to suffer severe attacks (Campo Grande, Chapadão do Sul, Sidrolândia, Bandeirantes, Camapuã, Jaraguari and Rio Negro).

According to the researcher responsible for the work, Andressa Lima Brida, pest monitoring is generally carried out based on the principles of Integrated Pest Management (IPM), which indicates the level of control action according to the number of insects identified in the monitoring. . For the mealworm, the level of control is still under study.

“However, the beating cloth is considered an essential tool for monitoring this pest. The adoption of soybean mealworm control strategies in agricultural crops presents a great challenge, since this insect shows quite peculiar behavior, with a habit of sheltering in straw or under clods of soil during the day, being protected against direct contact between insecticides during spraying, invalidating some applications. Currently, producers have invested in seed treatment, as it offers initial protection for seedlings in the phase considered most critical of insect attack. Added to this, it is essential to use chemical management and/or the association of biological products in initial sprays when the plant has its first pair of leaves, always rotate the active ingredients and, if possible, carry out nighttime applications, when the insect it is more exposed”, explains the researcher.

Most commercially available insecticides do not provide effective control. As a result, many producers end up adapting doses and mixtures. However, some active ingredients have demonstrated good results in reducing the population of these insects, such as fipronil, chlorpyrifos and thiamethoxan, imidacloprid, in addition to biological products, which have contributed to the pest management scenario. Many biological products based on entomopathogenic bacteria and fungi have demonstrated efficacy under laboratory conditions. Likewise, for many agricultural pests, presenting great potential when associated with chemical insecticides.

Microbiological insecticides based on microorganisms (fungi, viruses, bacteria and nematodes) are capable of infecting, incapacitating and killing insects. The mechanisms of action are varied and highly specific for certain species of insects, so that each application can result in the control of only a portion of the pest complex present in the crop. Insects, when infected by the fungus, lose their mobility and color, presenting a rigid and brittle body, and may sometimes be covered by mycelium and spores with a typical appearance and color of the associated entomopathogen.

“Little by little, research is beginning to identify the behavior of this pest, including its biology and ecology. Studies are being carried out to control this pest. Whether via seed treatment or spraying with different products, in addition to application technology, which is fundamental due to the complexity of the target, a combination of strategies will be needed to manage this pest. Carrying out correct identification, mapping behavior, defining the best times for application and adopting techniques recommended by integrated pest management are ways that can help producers deal with soybean mealworm”, concludes Andressa.