In recent seasons, some pests have led growers to adopt more strategies, due to difficulties and losses. There are great losses in soybean, corn and cotton crops in Brazil due to pests. Challenges are common with new pests, from lack of knowledge about biology, identification, problems with control alternatives and even wear and tear on certain strategies.

Factors such as the presence of hosts throughout the year, the plants remaining from previous “tiguera” harvests, combined with other factors such as favorable climatic conditions, high temperatures and mild winter, become ideal for breeding insects.

This greater number of insects is a great challenge for the producer who seeks to increase the productivity-profitability per area in recent years. However, tropical agriculture is a challenge and the inappropriate use of certain chemical insecticides and biotechnologies has led nature to give us an answer. Pests previously treated as secondary began to cause significant damage to crops (“pest shift”), in addition to those that already demonstrated high destructive potential, going through the process of resistance, making it unfeasible and increasing the need for control even more. control.

Phytophagous stink bugs are currently the most important pests in the soybean and maize production system. The brown plant bug, Euschistus heros (Heteroptera: Pentatomidae), is widely distributed in crops in the Cerrado region. However, other species of bed bugs enter the agroecosystem, such as the green-bellied bed bug (Dichelops (Diceraeus) melacanthus and D. furcatus), occurring in certain areas with great damage. This species has a shorter cycle, greater reproductive capacity, in addition to staying longer in the ground, attacking crops after emergence.

Generally speaking, stink bug damage in soybeans occurs during the reproductive phase as soon as the pods are formed, also commonly referred to as the “penknife” formation, leading to their drop and after poor kernel formation. At this stage, bedbugs concentrate in these parts, both in the form of nymphs and adults. In corn, the growing point of plants is the target in the initial phase, with bugs of the genus Diceraeus sp. which cause the greatest damage. Its stylet manages to reach the meristem of the plants, leading to a deformation of these, compromising the development and consequently the appearance of “dominated” plants that do not produce ears.

Bedbugs after harvest may still remain in the area – straw and other hosts, or even come out into adjacent areas. It is often a “remaining account”. This behavior has led to the implementation of management techniques for this pest right up to harvest, with population dynamics becoming increasingly important.

Faced with these difficult scenarios, only the rescue of integrated pest management, with a better knowledge of biology, sampling and good control strategies, will lead the grower to win these battles, bringing productivity and profitability to his business.

Germisson Tomquelski
Paul Chagas
Agricultural challenges