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M. Sc. Dissertations

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Subject: Zoology × End date: 2009 × Start date: 2009 ×
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    ThesisItemOpen Access
    Incidence of varroa destructor anderson and trueman (Acari: Varroidae) and its management in apis mellifera L. colonies
    (CCSHAU, 2009) Asha; Gulati, Rachna
    Studies on seasonal incidence of V. destructor in A. mellifera colonies revealed two peaks in its population, one in second fortnight of May (63.27 mites/hive) and second in first fortnight of July (34.75 mites/hive). Mite fall on sticky paper and hive debris was more in warmer months (May to August) than in colder months (November to January). Between the two methods of sampling, sticky paper method was found significantly better (CD = 0.11; p = 0.05) as more number of mites (17.58 mites/hive) were recorded than in hive debris sampling (11.41 mites/hive). Among abiotic factors, the mite population was significantly positively correlated with the maximum and minimum temperature. Maximum numbers of brood cells (15-17%) and adult bees (8-9%) were infested with V. destructor in second fortnight of May. Mite infestation showed a significant positive correlation with perforation of brood (r = 0.65; 0.83) and bee deformity (r = 0.97; 0.81) in both the sampling methods and negative correlation with colony strength and stores. The decreasing order efficacy of the various treatment against V. destructor is screen floor (98.8%)> powdered sugar(3g/ frame) (97.7%)> oxalic acid (3% top bar method) (88.2%)> powdered sugar(2g/ frame) (87.2%)> sulphur dusting (200g/ hive) (85.7%)> mustard stem powder (5g/ hive) (77.9%)> oxalic acid (3% trickling method) (76.3%)> oxalic acid (3% cotton swab method) (75%)> formic acid 85% (71.7)> mustard stem ash (5g/ hive) (69.8%).