Optimal Application Timing of Pest Control Tactics in Nonautonomous Pest Growth Model

Figure 5

The effects of the pest killing rates (𝑝₁,𝑝₂) and the releasing quantities (𝜎₁,𝜎₂) on the threshold condition 𝑅₀. The baseline parameter values are as follows: 𝑟(𝑡)=2+0.3cos(0.4𝜋𝑡), 𝑏(𝑡)=1+0.2sin(0.4𝜋𝑡), 𝛿(𝑡)=0.5+0.1cos(0.4𝜋𝑡), 𝑇=5, 𝜏₁=1, 𝜏₂=3. (a) The effect of the releasing quantities 𝑝₁ and 𝑝₂ on 𝑅₀ with 𝜎₁=2.5 and 𝜎₂=1.8; (b) the effect of pest killing rates 𝜎₁ and 𝜎₂ on 𝑅₀ with 𝑝₁=0.25 and 𝑝₂=0.2.

(a)

(b)