Pollination and fruit set in lingonberries (Vaccinium vitis idaea)

An investigation to study factors influencing fruit set in lingonberry (Vaccinium vitis-idaea) was carried out at the research farm at Ottarp in Southern Sweden. Cages covered with thin cotton cloth were used to isolate plants in the field. Fruit set within and outside the cages was studied. In addition flowers were manually self-and cross-pollinated. Fruit set was most frequent in connection with cross-pollination (64%) and open-pollination (58%). Corresponding figures for self-pollinated flowers and isolated flowers were 28% and 2%, respectively. The lingonberry flower thus tends to have reduced self-fertility and to be dependent on insects for a successful pollination.