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Table 1 Parameters in the system of difference equations ( 1 )-( 7 )

From: Effect of increased global temperatures on biological control of green lacewings on the spread of mealybugs in a cassava field: a simulation study

Parameter Definition \(\boldsymbol{t=25^{\circ}}\mathbf{C}\) \(\boldsymbol{t=27^{\circ}}\mathbf{C}\) \(\boldsymbol{t=30^{\circ}}\mathbf{C}\)
• Mealybugs
\(\alpha_{1}\) The fraction of mealybug’s eggs that develop into instar mealybugs in one time step 0.1075 0.1163 0.1493
\(\alpha_{2}\) The fraction of instar mealybugs that develop into adult mealybugs in one time step 0.0435 0.0482 0.0388
\(\alpha_{3}\) The natural death rate of adult mealybugs 0.0612 0.0665 0.0596
\(\alpha_{4}\) The fraction of female adult mealybugs in the reproductive period 0.4591 0.4991 0.4468
\(r_{1}\) The survival rate of mealybug’s eggs that develop into instar mealybugs 0.8900 0.8700 0.9120
\(r_{2}\) The survival rate of instar mealybugs that develop into adult mealybugs 0.7737 0.6079 0.6589
\(r_{3}\) The fraction of female adult mealybugs 0.7400 0.7200 0.8500
\(v_{1}\) The average number of eggs laid by a female adult mealybug in one time step 40.0000 36.5300 2.9126
• Green lacewings
\(\gamma_{1}\) The fraction of green lacewing’s eggs that develop into larva green lacewing in one time step 0.1639 0.2222 0.2703
\(\gamma_{2}\) The fraction of larva green lacewings that develop into pupa green lacewing in one time step 0.0521 0.0585 0.00625
\(\gamma_{3}\) The fraction of pupa green lacewings that develop into adult green lacewings in one time step 0.0714 0.0885 0.1053
\(\delta_{2}\) The natural death rate of adult green lacewings 0.0227 0.0175 0.0206
\(s_{1}\) The survival rate of green lacewing’s eggs that develop into larva green lacewing 0.8040 0.8210 0.8170
\(s_{2}\) The survival rate of larva green lacewing that develop into pupa green lacewing 0.9191 0.9629 0.7938
\(s_{3}\) The survival rate of pupa green lacewing that develop into adult green lacewings 0.9586 0.9614 0.7402
\(s_{4}\) The fraction of female adult green lacewings 0.5400 0.5500 0.4850
\(v_{2}\) The average number of eggs laid by a female adult green lacewings in one time step 7.2789 5.8237 2.3876