Clamer Valentina, Pugliese Andrea, Liessi Davide, Breda Dimitri
Department of Mathematics, University of Trento, Trento, Italy.
Department of Mathematics, Computer Science and Physics, University of Udine, Udine, Italy.
J Math Biol. 2017 Aug;75(2):419-441. doi: 10.1007/s00285-016-1088-z. Epub 2016 Dec 31.
Building from a continuous-time host-parasitoid model introduced by Murdoch et al. (Am Nat 129:263-282, 1987), we study the dynamics of a 2 host-parasitoid model assuming, for the sake of simplicity, that larval stages have a fixed duration. If each host is subjected to density-dependent mortality in its larval stage, we obtain explicit conditions for the existence of an equilibrium where the two host species coexist with the parasitoid. However, if host demography is density-independent, equilibrium coexistence is impossible. If at least one of the 1 host-parasitoid systems has an oscillatory dynamics (which happens under some parameter values), we found, through numerical bifurcation, that coexistence is favoured. Coexistence between the two hosts may occur along a periodic solution even without density-dependence. Models of this type may be relevant for the use of parasitoids as biocontrol agents of insect pests.
基于默多克等人（《美国博物学家》129卷：263 - 282页，1987年）引入的连续时间宿主 - 寄生蜂模型，我们研究了一个双宿主 - 寄生蜂模型的动态变化。为简化起见，假设幼虫阶段具有固定的持续时间。如果每个宿主在其幼虫阶段受到密度依赖的死亡率影响，我们得出了两个宿主物种与寄生蜂共存的平衡点存在的明确条件。然而，如果宿主种群统计学是密度独立的，平衡共存是不可能的。如果至少一个单宿主 - 寄生蜂系统具有振荡动态（在某些参数值下会发生），我们通过数值分岔发现，共存更受青睐。即使没有密度依赖，两个宿主之间也可能沿着周期解共存。这种类型的模型可能与将寄生蜂用作害虫生物防治剂有关。
