UF Blueberry breeding update James W. Olmstead | Associate Professor Horticultural Sciences Department

UF Cultivar Release Must adhere to current UF-IFAS standards. Must be approved for release by the Cultivar Release Advisory Committee and the IFAS Cultivar Release Committee. After release, Florida Foundation Seed Producers, Inc. handles commercialization for the University of Florida. 70% of royalty payments to UF come directly back to the blueberry breeding program.

Blueberry Cultivar Development Timeline Yr 1 Yr 3 Yr 5 Yr 7 Yr 9 Yr 11 Yr 13 Yr 15 Commercialization Cultivar release decision Multi-site trial evaluation Multi-site trial planting Third trial evaluation Third trial planting Second trial evaluation First trial evaluation First trial planting Seed germinate Crosses made Blueberry Cultivar Development Timeline Year Activity

Advanced Selection Trial Sites Suwanee Creek Farms Homerville, GA Straughn Farms Windsor/Waldo, FL Miller Blueberry Farm Interlachen, FL PSREU Citra, FL Dole Fruit Haines City, FL Island Grove Ag Prod. Arcadia, FL

KeecrispTM ‘FL06-556’

‘FL06-556’ (Keecrisp) ‘FL06-556’ is a low chill (300+ chill hours 0 to 7°C), mid to late- maturing genotype best adapted to production regions in north central Florida and south Georgia. The key attributes for ‘FL06-556’ are: Crisp fruit texture Upright architecture High yield when receiving adequate chilling Can be grown using hydrogen cyanamide with some yield loss Small dry picking scar Suitable for machine harvest and fresh marketing Higher chill requirement limits production in Central Florida Best adapted to a hydrogen cyanamide production system Often delayed leafing, even with hydrogen cyanamide application Late maturity Uneven fruit coloring at stem end + -

‘FL06-556’ (Keecrisp)

Titratable acidity (%) Fruit Quality – 2014-2015 Genotype Fruit wt (g) Fruit firmness (g/mm) Soluble solids (%) Titratable acidity (%) SS/TA ratio FL06-556 2.6 266 a 11.3 0.17 a 73.3 ab Arcadia 2.5 179 d 11.6 0.40 c 31.6 c Meadowlark 2.4 236 b 10.8 80.9 a Farthing 225 b 10.9 0.23 a 57.3 abc Endura 225 bc 10.7 0.24 ab 52.2 abc Emerald 198 cd 0.38 bc 34.1 bc Thresholds 2.0 g min. 150 g/mm min. 10% min. 1.0% max. >14

Bloom and Harvest Timing (2012-2015) CitraZ Waldo Citra   50% Bloom 50% Harvest Cultivar DOY (date) FL06-556 58±3 (2/27) 45±11 (2/14) 124±7 (5/4) 125±5 (5/5) Arcadia 46±6 (2/15) 46±6 (2/15) 115±4 (4/25) 115±4 (4/25) Endura 41±8 (2/10) n.a. 116±13 (4/26) 119±6 (4/29) Meadowlark 36±4 (2/5) 38±14 (2/7) 103±5 (4/13) 103±5 (4/13) Farthing 50±4 (2/19) 45±10 (2/14) 127±3 (5/7) 127±3 (5/7) Emerald 37±3 (2/6) 35±19 (2/4) 119±6 (4/29) 123±4 (5/3) Z No hydrogen cyanamide used at Citra trial.

Postharvest Trial – 2015 Partnered with USDA – US Hort Research Lab (Anne Plotto and Liz Baldwin). RA storage, trained panel testing after 7 and 14 days.

Fruit Quality and Yield Summary Yield data for FL06-556 were collected at Citra trials during 2014 and 2015. Trials at this location do not use hydrogen cyanamide, and the higher chilling requirement of FL06-556 is not suited for this type of management. Trial plantings in South Georgia and North Central Florida using hydrogen cyanamide have generated considerable interest among producers, although no harvest data are currently available. Fruit quality is excellent – crisp, low acid, spherical fruit that has stable sensory characteristics over postharvest life.

With crisp texture and improved plant architecture, producers can machine harvest and market the product fresh – decreasing labor costs and increasing profit margins.

IndigocrispTM ‘FL98-325’ – (USPPAF)

‘Patrecia’ (52-20)

‘Patrecia’ – Straughn Farms Program ‘Patrecia’ was never trialed by UF, and we do not have the typical data to support release as with cultivars from the UF breeding program. ‘Patrecia’ fits a definite need for North Central Florida growers, as it is early maturing (10 days before ‘Star’, similar to ‘Springhigh’) but has better fruit quality (large, firm, dry stem scar) than ‘Springhigh’.

‘Patrecia’

‘Patrecia’ Tight clusters – hand harvest only. Firm, large, oblate fruit, good presentation on the bush – pickers love to harvest this cultivar. Scar is not the smallest, but does not tear like ‘Springhigh’ Likely a temporary solution, but fits a niche in our current market timings.

UF-IFAS Blueberry Releases (2004-2015) Release Year Variety Outlook Notes 2004 Springhigh Decreasing Early season alternative but marketers do not want fruit 2005 Primadonna Stable Early season, but difficult to achieve full crop potential Snowchaser Minor Early but fruit quality often not ideal Sweetcrisp More acreage in Georgia 2007 Farthing Increasing Widely planted Ocala-north Scintilla Plant longevity is an issue 2009 Bobolink Has not been widely adopted Chickadee Interest in very low-chill areas in Central Florida Flicker Disease problems in Central Florida Kestrel Meadowlark More acreage in Georgia, Xylella an issue Raven 2013 Indigocrisp Currently in trial, propagation increasing Gainesville-north 2015 Arcadia Currently in trial, propagation increasing in South Central FL Avanti Currently in trial, propagation increasing Endura Currently in trial, propagation increasing in Central Florida To estimate chill requirement: Floral bud counts and staging were done on 3 canes per plant The percentage at or past bud break was evaluated per cane, and all canes were averaged. To determine chill hour requirement, there were 3 criteria: Which chill hour treatment had the highest number average of floral buds progress at or above bud break? If multiple chill hour treatments had the same average, which chill hour treatment got there first? If multiple chill hour treatments had the same average, got there at the same week, then what is the lowest chill hour treatment that produced these results? Graph used: Season 2 (2012-2013) data 2009 Stg. IV plant Location – Windsor Genotype – 06-205

Thank You! James Olmstead Associate Professor Institute for Food and Agricultural Sciences Horticultural Sciences Dept. University of Florida jwolmstead@ufl.edu http://www.hos.ufl.edu/faculty/jwolmstead