Blueberry Hybrids with Complex Genetic Backgrounds Evaluated on Mineral Soils: Flowering, Fruit Development, Yield and Yield Components as Influenced by Parental Species

Abstract

A blueberry ( Vacciniumsubsection Cyanococcus) population consisting of 15 blueberry cultivars and 39 interspecific hybrid selections resulting from combinations of nine Vacciniumspecies were evaluated in 1995 for flowering and fruit development parameters, yield and yield components after three years of growth on mineral soils. Substantial variation was uncovered among individuals for bloom date (7 May-22 May), date of first harvest (7 July-7 Aug.), ripening interval (54-90 days), harvest interval (6-23 days), yield (51-1324 g/plant), berry weight (0.52-2.24 g/fruit) and fruit number/plant (35-1390). Superior yielding individuals with interspecific hybrid backgrounds, Bluetta, Northland, Patriot', Sierra, Sunrise, US 625, US 644, US 645, US 652, US 654, US 665 and US 693 yielded in excess of I kg fruit/plant. When genotypes were grouped according to their genetic constitutions, significant effects of heritage were uncovered for bloom date, harvest date, ripening interval, harvest interval and fruit wt. Flowering and fruiting performance was also monitored to identify interspecific hybrids exhibiting the combined traits of positive mineral soil adaptation, high yield, large fruit size, high numbers of fruit/plant, late flowering, shortened ripening intervals, early ripening, and shortened harvest intervals. Although none of the individuals within the mineral soil-adapted hybrid group possessed all possible positive traits for flowering, fruit development, yield and yield components, most contained two or more characteristics which might be useful in further breeding efforts. Within this group US 645, US 665 and US 693 were considered to be superior based upon an early fruiting fresh-market ideotype.