THE EFFECT OF TEMPERATURE ON POLLEN VIABILITY AND GERMINATION CAPACITY OF SOME STRAWBERRY AND BLACKBERRY CULTIVARS

This studys important for determining the different temperatures’ effect (4, 18 and 24 ° C) on pollen germination and its viability for some strawberry (‘Premial’, ‘Clery’, ‘Real’, ‘Mira’, ‘Alba’, ‘Idea’, ‘Elsanta’, ‘Onebor’, ‘Benton’) and blackberry (‘Lock Tay’, ‘Williams’, ‘Arapaho’, ‘Black Satin’, ‘Navaho’, ‘Hull’) cultivars. The pollen viability was determined through the acetic carmine staining method. The fertile pollen was colored in red, and the sterile one in pink or it remained colorless (1.5 g agar + 15 g sucrose + 0.01 g boric acid in 100 ml distilled water), incubated 6-8 hours at all three temperatures and relative humidity 70-90%. The temperature affected the pollen germination and the cultivars germination capacity. The lowest pollen germination rate was obtained at 4 °C (between 19.4 1% and 54.72% for strawberry and 9.10% and 24.35% for blackberry). The best strawberry results were observed at 18 °C (57.97% in the Mira cultivar), respectively 24 °C (56.77% in the Elsanta cultivar) and at 18 °C (50.13% Williams variety), respectively 24 °C (55.55% Arapaho variety)