Lessons learned from 30 years of evaluating northern highbush blueberry genotypes – the importance of rotating plantings and using commercial production methods

Authors: JONES, PATRICK - Oregon State University; LUBY, CLAIRE - Non ARS Employee; STRIK, BERNADINE - Oregon State University; Mackey, Theodore - Ted; Hardigan, Michael; Finn, Chad

Submitted to: International Society for Horticultural Science Meeting
Publication Type: Abstract Only
Publication Acceptance Date: 9/1/2021
Publication Date: 9/1/2021
Citation: Jones, P., Luby, C., Strik, B., Mackey, T.A., Hardigan, M.A., Finn, C.E. 2021. Lessons learned from 30 years of evaluating northern highbush blueberry genotypes – the importance of rotating plantings and using commercial production methods. International Society for Horticultural Science Meeting. Virtual online meeting, August 30-September 1, 2021.

Interpretive Summary: Since the early 1990s, the USDA-ARS/OSU Cooperative Program has been actively testing highbush blueberry varieties and developing new breeding selections in order to produce improved highbush blueberry varieties adapted to the northwest region. The most promising genotypes are grown and tested at the North Willamette Research and Extension Center (OSU-NWREC) under conditions intended to reproduce commercial production practices. Ongoing breeding efforts and evaluation of advanced selections in trials at OSU-NWREC have led to the identification of several promising genotypes targeted for release: two perpetual flowering ornamentals that are also siblings (ORUS 285-1, ORUS 285-2), and a northern highbush selection the fruits during the 'Liberty' season (ORUS 264-1).

Technical Abstract: From 1990-1993, Oregon State University (OSU) evaluated genotypes from blueberry breeding programs in the USA to determine adaptation to Oregon. From 1993-present, this became part of the USDA-ARS/OSU Cooperative Program, expanding to include breeding new cultivars for the northwest. Over 250 genotypes have been evaluated at the North Willamette Research and Extension Center. In 1990 the 0.4-ha-trial was established using standard practices (amendment with sawdust, 1.2 x 3 m spacing, flat ground, sprinkler irrigation); the design was a CRD with five replications of three-plant plots per 40 genotypes. Bird control netting was installed to accurately assess yield. Results showed three replications and harvesting in years 4-6 were sufficient to detect meaningful differences. Good performing advanced selections were released (‘Chandler’, ‘Perpetua’, ‘Echo’, ‘Mini Blues’) and removed along with poor performing ones. New genotypes were added with three replicates. To change with the industry, sawdust mulch was added (late 1990s), then weed mat (mid-2000s), and irrigation switched to drip (early 2000s); however, fertigation was not possible. Plant performance declined after 2000, likely from replanting issues – over time the in-row area became depressed (soil loss) and compacted. In 2017 we transitioned to a new location. Genotypes are added in multiples of entire rows (3 reps) that have sawdust amendment, raised beds, drip irrigation, and weed mat mulch. Plants are fertigated and pruned to fruit in year 2 (observation) with yield collected in years 3-5. A green laser is used for bird control. Using standard commercial practices and designing plantings so rows can be properly prepared are critical to representative growth and yield. The following genotypes are slated for release: two perpetual fruiting ornamentals (ORUS285-1; ORUS285-2) and a northern highbush selection ‘Liberty’ season (ORUS264-1). Results of promising advanced selections will be presented.