Standardization of Rearing Technique for Neoseiulus (=Amblyseius) longispinosus, a Predator of two Spotted Spider Mite

摘要

Vegetables, being grown in the polyhouses in Himachal Pradesh, experience heavy damage due to the attack of two spotted spider mite, Tetranychus urticae (Koch) (Acari: Tetranychidae). Neoseiulus longispinosus (Evans) (Acari: Phytoseiidae) is a potential predator of this mite, which can be successfully used to control its population. The rearing technique of predatory mite was standardized by rearing T. urticae on bean plants raised in poly pots and releasing the counted number of predators on the infested bean plants. In the summer months multiplication of predator was found to be faster than in the winter months. Total life cycle of N. longispinosus was found to range between 7 to 14 days in the winter months of November and December. The predator:prey ratio required to wipe out population ofT. urticae in a week was found to be 1: 30 during July- August and 1: 17 during November-December.