Abstract
In Jordan, pollination is one of the problems faced by plants under plastic houses, in open fields and in off-season planting. Therefore this study was conducted in Jordan to investigate the role of pollinators and to investigate the systems of pollination in Nigella sativa species grown at two different altitudes, 150 m under sea level and 200 m above sea level. Up to now little attention has been paid to the events associated with pollination such as seed set, and to address this deficit, we examined six pollination treatments of the selected plant species. Field work was conducted, repeated and recorded from 2005 to 2007 in Jordan. Controlled pollinations were carried out in selected individual’s plant at the time of maximum stigma receptivity and anthesis. N. sativa flowers had anthesis intervals which last for five days, then followed by stigmatic receptivity which last for few hours. Plants are pollinated trough outcrossing and complete selfing to insure the reproductive assurance. However, self-pollination was occurred due to style movement. The observations confirmed that a mixing mating including a combination of out-crossing and selfing is a better strategy than selfing alone.