Economic threshold of Varroa destructor (Anderson and Trueman) infesting Apis mellifera in Kashmir

The economic threshold level of Varroa destructor (Anderson and Trueman) mite infesting the exotic honey bee, Apis mellifera in Kashmir valley was studied in 2008 and 2009. The economic threshold was determined through observations on the brood mortality and mite abundance on adult worker/drone bees exposed to different infestation levels viz., bees with 1- mite; 3-mites, 5- mites, and bees without mites (control). Results showed that at the 1,3 and 5- mites infestation levels, the fixed cost per frame of bees worked out to be Rs. 144 while variable costs per frame worked out at the 1,3 and 5- mite infestation levels was Rs.165, 219 and 267, respectively, as compared to control, in which the variable cost was Rs. 36 only. The studies concluded that with increase in the level of infestation, there was corresponding increase in the variable costs, as compared to control where variable costs were very low.