title: Discrete-time host-parasitoid models with pest control.
abstract: We propose a simple discrete-time host-parasitoid model to investigate the impact of external input of parasitoids upon the host-parasitoid interactions. It is proved that the input of the external parasitoids can eventually eliminate the host population if it is above a threshold and it also decreases the host population level in the unique interior equilibrium. It can simplify the host-parasitoid dynamics when the host population practices contest competition. We then consider a corresponding optimal control problem over a finite time period. We also derive an optimal control model using a chemical as a control for the hosts. Applying the forward-backward sweep method, we solve the optimal control problems numerically and compare the optimal host populations with the host populations when no control is applied. Our study concludes that applying a chemical to eliminate the hosts directly may be a more effective control strategy than using the parasitoids to indirectly suppress the hosts.
authors.affiliation: Department of Mathematics and Statistics, Texas Tech University, Lubbock, TX 79409-1042, USA. srjjang@gmail.com
authors.forename: Sophia R-J
authors.initials: SR
authors.lastname: Jang
authors.forename: Jui-Ling
authors.initials: JL
authors.lastname: Yu
mesh_terms: D003198:Computer Simulation; D006790:Host-Parasite Interactions; D008954:Models, Biological; D010571:Pest Control; D013997:Time Factors