Production, survival and germination of bilberry ( Vaccinium myrtillus L.) seeds

Summary Bilberry (Vaccinium myrtillus L.) is a prominent species in moorland and woodland vegetation which spreads and survives mainly by vegetative growth from buds. Each berry contains many seeds but seedlings are rarely seen in Scotland. Thus, it is of interest to establish whether the lack of seedlings reflects a low production of viable seeds, their dormancy status, or germination requirements or seed longevity. Samples of V. myrtillus berries were collected from moorland in the east Grampian mountains, Scotland. Each berry contained about 70 seeds. Small seeds did not germinate but large fresh seeds achieved over 80% germination in laboratory tests. Seeds stored dry for one year did not lose viability. Seedsstored in moist cold conditions (to mimic conditions in the soil over winter) lost viability progressively and none germinated after about 43 weeks. Germination occurred over the range 15–24°C. These seed germination and longevity characteristics may currently severely limit the window of opportunity for germination of seeds of V. myrtillus in Scotland and have implications for the spread of V. myrtillus if average temperatures increase.