CSK HPKV, Bee Research Station, NagrotaBagwan - 176047, Himachal Pradesh, India
**Department of Organic Agriculture, College of Agriculture, CSKHPKV, Palampur - 176 062, Himachal Pradesh, India
Three chemicals viz. sulphur (0.2 g per frame at weekly interval for five weeks), 85 per cent formic acid (3 ml per colony on alternate days for five weeks) and thymol crystals (1, 2 and 3 g per colony applied only once) were evaluated for their effectiveness against
Apis mellifera, formic acid, sulphur, thymol, Varroa destructor