EFFECT OF SOIL MOISTURE AND FERTILIZER ON THE POTENTIAL AND ACTUAL YIELD OF LOWBUSH BLUEBERRIES

Abstract
Lowbush blueberry (Vaccinium angustifolium Ait.) plants were evaluated under greenhouse and field conditions to determine the effect of soil moisture stress and fertilizer applied during the year of bud formation on plant growth and development. Greenhouse plants grown under water treatments of 0.2 (about field capacity), 0.6, 1.0 and 5.0 bars did not differ significantly in number of stems per plant or flower buds per stem. A significant increase in the number of flowers per stem was detected for the 0.2- and 0.6-bar treatments over the 1.0- and 5.0-bar treatments. A highly significant trend was an increase in flowers per plant related to an increase in water application. Established field plants had no significant difference in the number of flowers between the unirrigated control and the 0.6- or 0.2-bar treatments. The number and total weight of berries increased significantly with increased water availability during the vegetative growth year but individual berry size remained the same. Irrigation during the year of bud formation may result in increased yield during the crop year. No significant fertilizer application effect was detected on the parameters evaluated.Key words: Vaccinium angustifolium, flower buds