Optimal Control of Agricultural Insects with a Stage-Structured Model

Figure 5

Phase portrait of system (2) to see the effect of the proportion of killed immature and mature 𝛼 and 𝛽 with 𝑎=0.6, 𝑏=0.8, 𝑐=0.5, 𝑑=0.2, and ℎ=1. (a) 𝛼>𝛽. (b) 𝛼=𝛽. (c) 𝛼<𝛽.

(a)

(b)

(c)