About 6000 ha of blackberry ( Rubus L. subgenus Rubus , Watson) was harvested in the United States in 2012 [ U.S. Department of Agriculture (USDA), 2014 ]. Oregon was the leading producer with 2500 ha, most of which were trailing types grown
Emily K. Dixon, Bernadine C. Strik, Luis R. Valenzuela-Estrada, and David R. Bryla
Franco Famiani and Robert P. Walker
The ripening of blackberry, like many other fruits, is accompanied by color, respiratory, and compositional changes, together with softening ( Perkins-Veazie et al., 2000 ; Tosun et al., 2008 ; Wrolstad et al., 1980 ). There is a large decrease
Renee H. Harkins, Bernadine C. Strik, and David R. Bryla
Recent surveys show a shift toward more organic blackberry production worldwide ( Strik et al., 2007 ). Approximately 200 ha of organic blackberry are currently planted in the United States, 74% of which are located in California and Oregon
John R. Clark
Eastern U.S. blackberries are heterogeneous tetraploids. Some traits have been quite difficult to improve, and the example of erect-caned, thornless cultivar development is a good example. Thornlessness was associated with semi-erect canes, poor seed germination, and other undesirable traits, thus extending the amount of time to achieve an erect-caned, thornless cultivar. The first release of this type was `Navaho' in 1989. Primocane fruiting is a trait that would not likely be considered intractable, but did not gain substantial attention until the late 1980s. Subsequent work in primocane fruiting has shown substantial progress in a relatively short time of breeding emphasis for this trait. Fruit size gains have been substantial, and even though this trait might be considered intractable, progress has been significant in the last 40 years. Excellent postharvest handling and flavor are additional traits which one might consider intractable. Substantial progress has been made in improving fruit quality for shipping, providing for an expansion in fruit shipped to distant markets. These and other improvements are expanding opportunities for blackberry growers worldwide.
Bernadine Strik, Juliet Mann, and Chad Finn
Twenty-one genotypes of blackberry (Rubus L. subgenus Rubus Watson) were evaluated for percent drupelet set in 1993 and eleven genotypes were evaluated in 1994. Commercial cultivars were chosen to represent types (trailing, erect, and semi-erect) of blackberries grown in the United States. Secondary fruit were picked when green but developing a red blush during the early- and late-ripening season. Drupelets and pistils per fruit were counted to calculate percent set. In 1994, ripe fruit ranging in size were harvested for `Boysen', `Marion', `Thornless Evergreen', and `Chester Thornless' and drupelet per fruit were counted. Drupelet set among genotypes ranged from 40% to 86% in 1993 and 39% to 78% in 1994. Most genotypes had a higher percent set on early flowers compared to later ones. Drupelet set and number were not correlated with fruit weight among genotypes. In `Boysen', `Marion', `Thornless Evergreen', and `Chester Thornless', drupelet number was correlated with fruit weight, although the relationship in `Chester Thornless' was not as strong as the others. It is unclear what factors limit drupelet set in the genotypes studied.
Creighton L. Gupton and Barbara J. Smith
A study was conducted to determine if blackberry cultivars Humble, Rosborough, and Brazos transmit rosette (incited by Cercosporella rubi) resistance and to estimate heritability (h2). Plants of parents and offspring involving these cultivars were rated for rosette severity on a whole plant basis from 0 = no rosette to 7 = all buds infected or plant dead. An estimate of h2 was computed by regression of cross means on parental means. The mean rosette severity rating of plants from crosses was always intermediate between the cultivar and other parents. Only `Humble' transmitted enough rosette tolerance to be usable although `Rosborough' crosses were more tolerant than the other parents. The h2 estimate of 0.48 was fairly high but low variability among parents other than `Humble' would suggest little progress from mass selection.
Chad E. Finn, Bernadine C. Strik, Brian M. Yorgey, Mary E. Peterson, Patrick A. Jones, Jungmin Lee, Nahla V. Bassil, and Robert R. Martin
‘Hall’s Beauty’ is a new, early-ripening, high-quality, firm, and sweet thornless trailing blackberry ( Rubus subg. Rubus Watson) cultivar with extremely large and attractive double flowers from the U.S. Department of Agriculture, Agricultural
Bernadine C. Strik and Gil Buller
Soft-tipping (removal of 2–5 cm) primocane-blackberry canes once ( Drake and Clark, 2003 ; Strik et al., 2008 and 2012 ; Thompson et al., 2009 ) or double-tipping (main cane and branches; Thompson et al., 2009 ) has been shown to increase yield
Amanda J. Vance, Patrick Jones, and Bernadine C. Strik
The Pacific Northwest region of the United States is an important growing region for the production of blueberry ( V. corymbosum L.), blackberry ( Rubus L. subgenus Rubus , Watson), raspberry ( R. idaeus L.), and strawberry ( Fragaria
Javier Fernandez-Salvador, Bernadine C. Strik, and David R. Bryla
Fertilizer practices in blackberry ( Rubus L. subgenus Rubus Watson) are routinely adjusted based on leaf tissue analysis ( Hart et al., 2006 ). N is the predominant nutrient applied to trailing blackberry, and the best growth and yield are