Tolerance of lowbush blueberries (Vaccinium angustifolium Ait.) to drought stress. I. Soil water and yield component analysis

Abstract

A 2-yr field study examining the effects of drought conditions on the vegetative and reproductive components of the lowbush blueberry (Vaccinium angustifolium Ait.) was completed at the Nova Scotia Wild Blueberry Institute (NSWBI), Debert, NS, in 1998 and 1999. Drought and irrigation treatments were applied over 2 yr in either or both the vegetative and cropping years of production. In general, during the 2-yr study of the vegetative stage, soil moisture levels in the uppermost 0- to 15-cm depth were low (5 to 22%) due to lack of rainfall and increased plant demand. Although berry weight was not affected by drought treatments, berry number was > 50% higher in response to irrigation in both the vegetative and cropping years. From yield component analysis, it was concluded that node number increased at the expense of floral zone length in response to drought-stress. It appeared that the wild blueberry has adapted to partition its resources into vegetative growth under soil moisture limiting conditions, and into reproductive growth when moisture levels are sufficient. Key words: Yield, path analysis, irrigation, drought