Biocontrol of Spodoptera frugiperda: modeling the spatio-temporal dynamics of a host-parasitoid system via a reaction-diffusion model

• Grant number: 19/14834-7
• Support Opportunities: Scholarships in Brazil - Post-Doctoral
• Effective date (Start): October 01, 2021
• Status: Discontinued
• Field of knowledge: Biological Sciences - Ecology - Theoretical Ecology
• Principal Investigator: Wesley Augusto Conde Godoy
• Grantee: Lucas dos Anjos
• Host Institution: Escola Superior de Agricultura Luiz de Queiroz (ESALQ). Universidade de São Paulo (USP). Piracicaba , SP, Brazil
• Associated research grant: 14/16609-7 - A multi - and interdisciplinary approach to understand spatio-temporal patterns of insect pests and design landscapes for sustainable pest management in tropical agricultural systems, AP.TEM

Abstract

Biological control (biocontrol for short) is the tactic in which an organism (called a biocontrol agent) is used to reduce the population density of another organism (usually a pest species). The release of control agents against agricultural pests is a common tactic undertaken to slow down or to carry out suppression of these pest populations to tolerable levels, and it has some advantages in relation to the chemical control: less environmental impact, absence of risks for human health and, moreover, it does not exert selection pressure to generate resistant individuals. Two reasons that potentially affect the success of biological control are the rate of dispersion and the tactic of introduction of these biocontrol agents. In this study, our plan is to develop deterministic mathematical models to investigate the efficiency of biological control of the agricultural pest Spodoptera frugiperda. The basic model is composed of a system of two partial differential equations in one spatial dimension, considering simultaneously the dispersal and population dynamics. The biological control system is such that an egg parasitoid, the species Trichogramma atopovirilia, is deliberately released in three agricultural scenarios to control the pest: (a) homogeneous monoculture; (b) monoculture with Bt and non-Bt crops; and (c) polyculture with three crop species: corn, oats and soybeans. Given this description, we want to assess the influence of the following factors in the biological control efficiency: (I) parasitoid diffusivity (i.e., speed of dispersal); and (II) different tactics of the parasitoid release. It is important to mention that the expected results will be obtained for spatially structured populations by considering explicitly the speed of dispersal of the control agent and the pest. Feedback from theoretical models as the ones constructed in this work can provide useful guidelines for practitioners in biological control. Finally, we present two extensions of the discussed reaction-diffusion model: the addition of a term meaning directed motion due to searching behavior, and the consideration of two spatial dimensions. (AU)

Scientific publications

(References retrieved automatically from Web of Science and SciELO through information on FAPESP grants and their corresponding numbers as mentioned in the publications by the authors)

COSTA, MICHEL ISKIN DA S.; DOS ANJOS, LUCAS. Intraguild predation does not necessarily have negative effects on pest biological control: insights from a multiple consumer-multiple resource food web population model. BIOCONTROL, v. 67, n. 3, p. 12-pg., 2022-03-21. (19/14834-7)

DOS ANJOS, LUCAS; NAOZUKA, GUSTAVO TAIJI; VOLPATTO, DIEGO TAVARES; GODOY, WESLEY AUGUSTO CONDE; COSTA, MICHEL ISKIN DA SILVEIRA; ALMEIDA, REGINA C.. A new modelling framework for predator-prey interactions: A case study of an aphid-ladybeetle system. ECOLOGICAL INFORMATICS, v. 77, p. 15-pg., 2023-06-28. (19/14834-7, 18/02317-5)