Otimização do controle de Diatraea saccharalis (Fabricius, 1794) (Lepidoptera: Crambidae) por meio do parasitoide Cotesia flavipes (Cameron, 1891) (Hymenoptera: Braconidae) visando a redução de custos
Abstract
Brazil is the world’s largest producer of sugarcane. However, this agricultural crop
is attacked by pests, especially Diatraea saccharalis. Its control in Brazil is carried out
mainly by the action of the caterpillar parasitoid, Cotesia flavipes. Therefore, understanding
how the interaction between these two species occurs is vital to increase the
effectiveness of this control. This thesis’ goals are to improve the description of the dynamics
among populations and to transform this information into a tool to optimize the
biological control of this pest, focusing at the cost reduction for the farmer. In order to describe
the dynamics of these two populations, the Lotka-Volterra model and a multi-agent
simulation were employed. Through the first model, the characteristics of the differential
equations system were obtained, and treatment suggestions to be field tested were
presented, in case the pest population size is known. The multi-agent simulation, which
by its construction presents more realistic characteristics compared to the Lotka-Volterra
model, played a crucial role in the description of the pest in its life cycle phases, where
behaviors not observed in the first model were obtained. Afterwards, biological control
optimization was developed, taking into account the financial damage that the pest causes
in a given period and the cost of its treatment. In order for this procedure to become a
useful tool in the farms, an improved survey method has also been proposed. Finally, the
results developed here present new solutions so that the biological control of this main
sugarcane pest can be carried out more effectively, contributing to the reduction of the
employment of chemical products and increasing the competitiveness of this Brazilian
industry.