Ali Imani - Corresponded author; Departments of Horticultural Science, Seed and Plant Improvement Institute (SPII)Karaj, Iran.
Saber Eksiri - Departmentof Horticultural Science, Faculty of Agriculture, Abhar Azad University, Abhar, Iran
Saeed Piri - Departmentof Horticultural Science, Faculty of Agriculture, Abhar Azad University, Abhar, Iran
Dariush Davoodi - Department of physiology and breeding, Agricultural Biotechnology Research Institute of Iran (ABRII), Karaj, Iran

In this experiment, effects of pollen source of ‘Siah Mashhad’, ‘Sorati’, ‘Zodras’ and ‘Stella’ cultivars on fruit set and pollen tube growth of sweet cherry (Prunus avium L.)CV. ‘Tak Daneh Mashhad’ was studied as randomized complete block design (RCBD) in triplicate statistically. The results showed that ‘Siah Mashhad’, ‘Sorati’, ‘Pishras’ and‘Sky’cultivars are the suitable pollinizers for ‘Tak Daneh Mashhad’ cultivar, and also ‘TakDaneh Mashhad’ cultivar is a self- incompatible cultivar, which produced the most fruit in crosspollination, it should be used as mixculture for orchard establishment. Results of this research showed that fruit set in pollination combinations was different. So that the highest fruit set was in‘Tak Daneh Mashhad’ (38%) using ‘Pishras’ pollen grains, while the lowest was fruit set (22%)in this cultivar by ‘Sky’ pollen grains. Also, this investigation showed that the pollen tubegrowth in style with different treatments was different. But, only compatible pollen tube reached to base of style and the time required 120 hours after pollination was determined. These microscopic examinations and observations confirmed the obtained results from controlled hybridization in garden.