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The present study was carried out to determine the effects of screen bottom board trays on reducing ectoparasitic mite Varroa destructor Anderson and Trueman (Acari:Varroidae) populations in honeybee Apis mellifera linguistica (Hymenoptera: Apidae) colonies in the winter, spring and summer season (2013-14). Four honeybee colonies were exposed to oxalic acid (3.2%), thymol (0.5 g) and formic acid (65%) on screen bottom boards in winter, spring and summer seasons. The fourth group had screen bottom board trays but without any chemical. There was a trend of fallen mean number of mites 157±6.28, 97±3.81, 132.75±9.76 and 26±1.68 in winter, 160±20, 149±30, 161.75±18.5 and 27.5±1.04 in spring and 188.25±5.34, 196.25±5.48, 144.25±7.74 and 34.5±4.94 (Mean±SE) in summer, respectively. The average efficacy (%) of the four groups were 86±.58, 66.5±3.93, 75±7.04, 18.25± 10.25 in winter, 77±3.52, 76.75±30, 79±2, 18.25±0.75 in spring and 74.75±1.44, 65.75±1.11, 63±2.04, 18.25±1.11 in summer season, respectively. No queens were lost, and there was no adult honeybee mortality in any of the colonies during the experiment. It can be concluded that screen bottom board trays alone and with soft chemicals in all three seasons effectively control the Varroa mite and can be used without any side effect during all the three seasons. [ABSTRACT FROM AUTHOR]

To evaluate the acaricidal effects of some plant oils and tobacco extract on Varroa destructor mites, a study was conducted in laboratory as well as in bee hives at Honeybee Research Institute, NARC, Islamabad. In the lab experiments, clove oil and tobacco extract both proved to be equally effective against mites. The treatments were significantly effective when applied in 5% as compared to 10 and 15% concentrations. The most effective combination was clove oil and tobacco extract when used in 5% concentration for 24 h. In the field experiment all the oils/extract individually and in combinations confirmed clove oil + tobacco extract (T14) the best combination with 96.48±0.52 efficacy. The honey produced in kg was found maximum 20.5±0.29 in treatment T14. The highest number of fallen Varroa mites 381.67±24.31 was also occurred in T14 treatment and difference between the treatments was highly significant. No queens were tost and there was no adult honeybee mortality in any of the colonies during the experiment. A Completely Randomized Design (CRD) was applied to all laboratory and field experiments. It was concluded that clove oil + tobacco extract (T14) can play an important role in an integrated pest management program to control Varroa mite in honeybee colonies. [ABSTRACT FROM AUTHOR]

After designing new pollen trap a trial was laid down in March, 2011 in the premises of HBRI, NARC, Islamabad on sixteen honeybee colonies. All the colonies selected were alike with respect to number of frames and bees present in them. The colonies were divided into four groups. On the first group the Gujranwala (local) pollen trap was clipped while on the second group the newly devised HBRI trap was clipped, on the third group bottom board pollen trap was fitted and on the fourth group Chinese pollen trap was clipped. The pollen drops down through the screens into pollen tray. The weight of pollen collected was compared and it was found that newly design pollen trap (second group) highly significant differ as compared to other three groups (Gujranwala, bottom board, china trap). The total yield of pollen from Gujranwala trap, HBRI, fixed bottom board and the china clipped trap in gm were found to be 83.00 ± 3.92 (Mean ± SE) ,121.50 ± 2.87 (Mean ± SE), 79.50 ± 2.33 (Mean ± SE), 66.00 ± 1.78 (Mean ± SE) respectively. The honey extracted from bee hives with all types of pollen traps was compared and no difference was observed in honey yield. [ABSTRACT FROM AUTHOR]