Development and quality of cloudberry (Rubus chamaemorus L) as affected by female parent, male parent and temperature.

n this study we investigated the interaction between temperature and genotype on fruit development and levels of total phenols and anthocyanins in cloudberry. The experiment was done in a phytotron using one female (‘Fjellgull’) and one hermaphroditic (‘Nyby’) cultivar. Plants were grown at 9, 12, 15 and 18◦C in 24-h photoperiod. The female cultivars were pollinated with pollen from a male (‘Apollen’) clone and from the hermaphrodite clone. Parthenocarpic fruit development was induced by gibberellic acid (GA 3 ). Ripe berries were frozen individually at −80◦C and stored until analyses. There was a linear,double logarithmic relationship between temperature and number of days from pollination/GA 3 -treatment to ripening. ‘Fjellgull’ had significantly larger berries than ‘Nyby’, and the largest berries were obtained at 12 and 9◦C. Pollen clone did not have asignificant effect on berry size. GA 3 induced parthenogenesis in ‘Fjellgull’ and partial parthenogenesis in ‘Nyby’. In ‘Fjellgull’,the parthenocarpic berries were comparable to pollinated ones at low temperatures, but at 18◦C their development was restricted.The level of total anthocyanins was significantly higher in ‘Fjellgull’ than in ‘Nyby’, and these levels were significantly enhanced at 9 and 12◦C compared to higher temperatures. Levels of total phenolic compounds were not significantly affected. In conclusion,the present results indicate that low temperature is favourable both for size and quality of cloudberries.