ABSTRACT:The objective of this study was to determine suitable cultivars to be used as pollinators for 0900 Ziraat. 0900 Ziraat was used as a female cultivar; Bigarreu Gaucher, Bing, Noble, Starks Gold, Stella, Van, and Vista were used for pollination in the experiments. Starks Gold had the highest values in terms of anther number, average number of pollens per anther, number of pollen per flower and the morphological homogeneity. The pollen viability rates showed significant differences according to stain tests. In vitro pollen germination in 0.5% agar + 15% sucrose + 5 ppm boric acid medium increased with increasing incubation period, and the highest germination was obtained after 48 hours for all cultivars. In orchard trials parallel to pollen tube growth experiments in the laboratory, 0900 Ziraat × Starks Gold combination gave the best fruit set results. incompatible (Janick, Moore 1996;Thompson 2004). Pollen viability could be assessed by different methods like staining with nuclear or non-vital dyes or in vitro germination tests (Parfitt, Ganeshan 1989; Heslop-Harrison et al. 1984;Koyuncu et al. 2000;Voyiatsiz, Paraskevopoulou-Paroussi 2002). The aim of the staining techniques is to determine the pollen enzymatic activity, membrane integrity and stainability of the nucleus (Norton 1966;Vizintin, Bohonec 2004). Stain tests are faster and easier than pollen germination tests but, in some cases, different results may be obtained with them in many fruit species or cultivars. Therefore, to determine the actual amount of viable pollen, germination tests are necessary. The 'hanging drop' and 'agar in plate' tests are generally used to determine the in vitro pollen germination rate (Koyuncu et al. 2000;Vizintin, Bohonec 2004).The objectives of this study were to investigate the pollen performance of some sweet cherry cultivars and to determine a suitable pollinator for 0900 Ziraat, which is the major cultivar produced in Turkey (also for export). For this purpose, pollen viability, pollen production, pollen germination rate, and pollen tube lengths were assessed under in vitro conditions; hand pollination was also done in vivo. The experiments were conducted twice over a two-year period with consistent results and the data presented here were obtained in the second experimental year.
MATERIALS AND METHODSThis work was carried out on a sweet cherry collection maintained at the Uluborlu Municipality Orchards located in the northwest of Isparta, Turkey. The latitude is 38°10´, longitude is 30°37´, and altitude is 1,050 m. Bigarreu Gaucher, Bing, Noble, Starks Gold, Stella, Van, and Vista cultivars were used as pollinators and 0900 Ziraat was used as a female cultivar.
Phenological observationThe phenological stages were determined by a direct observation in the orchard.
Pollen performancePollens were obtained from flowers of the abovementioned cultivars at balloon stage. The flowers were transferred to the laboratory immediately. Anthers were removed and placed into the dark-colored bottle to promote dehiscence at ro...
