A study on the determination of mutual relations between honey bees (Apis mellifera L.) and oil rapeseed (Brassica napus l.) grown in the Black Sea coastal zone

This study was carried out to determine some relations between honeybees and oilseed rape plants under the Samsun province ecological condition during two years. In the first year, oilseed rape plants was stayed at flowering during 44 days, had 2694 number/m2 flowers, produced 1.89 kg/da nectar and 1330 kg/da pollen per day; second year, oilseed rape plants was stayed at flowering during 39 days, had 701 number/m2 flowers, produced 0.38 kg/da nectar and 332 kg/da pollen per day. According to the two-year results, it was determined that length of flowering rape plants average of 41.5 days. Oilseed rape plant produced 0.23 mg/flower/day nectar which contains 20.25% dry matter and 0.48 mg/flower/day pollen. Oilseed rape pollen has determined 31.22 % rate from colonies located near the rapeseed plants and honey were found multifloral structure. In addition, offspring area in the colonies near of the plant was higher than away from colonies. It was found that average amount of seeds obtained from the closed area was 271.4 kg/da, average amount of seeds obtained from caged area with honeybee was 373.9 kg/da and average amount of seeds obtained from completely open space to the insect pollination was 325.3 kg /da. As a result; in the Black Sea coastal region condition, it was found that many insects especially honey bees benefit from pollen and nectar of oilseed rape. It can be support plant for honeybee colonies and other insects as nectar and pollen sources in field when has got poor flora.