Stage Structure Continuous Mathematical Model on Sterile Insect Technique
by
D.K. Bhattacharya
Department of Pure Mathematics, University of Calcutta, Kolkata- 700 019, India

The talk centers round stage structure continuous mathematical model on SIT (Sterile Insect Technique) and its application for control of pests. Normally adult stage is considered for control of pest. But so far as pest damage is concerned, stage structure is found to be more realistic than non-stage structure, because for pests larval stage is more harmful than the adult stage in most of the agricultural system. Anyway in earlier work, generation was assumed to be non-overlapping, and so stage structure discrete dynamic model was chosen for Sterile Insect technique. But overlapping generation is found to be more realistic. This is why; we prefer stage structure continuous mathematical model for using SIT for pest control. Incidentally it may be remarked that earlier SIT was used usually to eradicate pests as a part of total pest management. But this is not supported ecologically. So we try to formulate models for control of pests and not for their complete eradication.

We consider the application of SIT with and without migration. We consider only the hard release for sterile males and also for migrated pests, as hard release is more realistic than soft release in both the cases. Further in both the cases, whether migration is allowed or not, we investigate the models analytically, regarding their stability, oscillatory behavior and such others and interpret the results biologically as far as possible. Finally we verify all the results through simulation.

Date received: February 27, 2007