Advancing Blueberry Production Efficiency by Enabling Mechanical Harvest, Improving Fruit Quality and Safety, and Managing Emerging Diseases

The exponential expansion of the southern blueberry industry during the past three decades has been a remarkable success story within the U.S. specialty crops sector. Nearly one-third of the cultivated blueberry acreage is located in the South, and within the next 5 years the region is projected to become the largest blueberry-producing area in the nation. Growth in acreage and production has been especially rapid for the early-maturing southern highbush blueberries, which ripen during a favorable market window and provide an important source of income for small and medium-sized farms and a lifeline for the surrounding rural communities. However, in the face of increasing domestic supply, rapidly strengthening international competition, increased pressure on producer prices, and looming shortages in labor, southern blueberry growers will have to elevate their overall production efficiency considerably to remain profitable. This Coordinated Agricultural Project, funded in the first round of the Specialty Crop Research Initiative (SCRI) grants competition in 2008, is enabling an unprecedented leap in efficiency through a comprehensive, multi-disciplinary effort integrating three major themes: 1) overcoming the genetic, horticultural, and engineering barriers that stand in the way of machine-harvesting highbush blueberries for the fresh market; 2) improving overall fruit quality and safety; and 3) addressing emerging diseases that threaten the viability of the industry. An economic re-evaluation of the production chain, together with comprehensive efforts in outreach and technology transfer, ensures that new knowledge and technologies is being transitioned to practice. Key results and deliverables from the first year of this project will be discussed, focusing on breeding and comprehensive cultivar evaluation (especially of novel genotypes having crispy-textured berries) for mechanical harvestability; evaluating horticultural practices such as trellising, modification of bush architecture, and application of abscission agents to reduce losses during mechanical harvest; understanding pre- and postharvest factors affecting quality and consumer acceptability of southern highbush blueberry fruit; elucidating epidemiology and management of rapidly expanding systemic diseases, particularly stem blight (caused primarily by Neofusicoccum ribis and Lasiodiplodia theobromae), bacterial leaf scorch (caused by Xylella fastidiosa), and necrotic ring blotch (caused by Necrotic ring blotch-associated virus); and determining factors that affect blueberry producer willingness to adopt new technologies (such as machine harvester investments). Our research and outreach activities are being coordinated and integrated with other funded projects related to southern blueberry production and markets, notably the 2009 SCRI blueberry eXtension project and the 2008 NRI small-midsize blueberry farm prosperity project.