Application of Non-Linear Programming in Apple Orchards Pest Control

Toxicity of an caricide and an insecticide was investigated against the two species of mites, Panonychus ulmi (Koch) and Tetranichus urticae (Koch) and one of their predatory mites, Typhlodromips swrirskii (Athias-Henriot) under laboratory conditions. Standard bioassay's procedures through non-linear programming (NLP) approach were used to determine the efficiency of two pesticides mixture on the predatory mite. In contact bioassay tests, 0, 200, 300, 400 and 500 mu l L-1 and 0, 100, 200, 250 and 300 mu l L-1 of fenpyroximae and thicloprid were employed against the three mite sprcies, respectively. Mortality rate was recorded 72-hour post treatment. Based on the mathematical programming framework, the most optimum concentration in the mixture of fenpyroximae and thicloprid was 86 mu l L-1 and 4 mu lL(-1), respectively. In addition, the proposed non-linear programming model was solved by the standard simplex algorithm. The revenue obtained was higher than that of the corresponding conventional pest-control measures. The model produced an optimal apple production scheme that gives higher income than that obtained from the conventional grower's plan. The NLP approach had the total production cost (10,105,600 R), while based on conventional pesticide's application the total cost was (18,700,000 R). The cost difference was 45.96 percent. It could be suggested that the non-linear programming model was a useful tool for apple orchards integrated pest management program.