SCIENTIFIC PAPERS

Scientific Papers, USAMV Bucharest, Series A, Vol. LII, 2009, ISSN 1222-5339NECESSITY OF POLLINATION BY MELLIFEROUS BEES ATSUNFLOWER HYBRIDS ACTUALLY CULTIVATED IN ROMANIAV. ION*, V. ŞTEFAN*, NICOLETA ION***University of Agronomic Sciences and Veterinary Medicine of Bucharest**Apiculture Research and Development Institute of BucharestKeywords: sunflower, pollination, melliferous beesAbstractWithin this paper there are presented the results of the researches carried out in the period2002-2008 at an assortment of 34 sunflower hybrids with respect to the visit frequency ofthe pollination insects on the sunflower heads, the percentage of self-fertility and the gainin seed yield through pollination, compared to the yield obtained under self-fertilityconditions. The experiments were carried out within the experimental farm belonging to theUniversity of Agronomic Sciences and Veterinary Medicine of Bucharest, located on areddish preluvosoil at Moara Domnească (15 km faraway from Bucharest on North-Eastdirection). The results of researches show that the sunflower growers have to pay attentionof bringing the beehives for pollinating the sunflower crops, in view to get a gain in seedyield up to 1390 kg per hectare, according to the hybrid. The melliferous bees arenecessary especially for the hybrids with the highest gain in seed yield and small selffertilitypercentage, but also for the other hybrids in view to be sure the pollination isassured under any climatic conditions.338