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Blueberry Tree Research Could HelpGrowers Branch OutDenise RuttanOregon State UniversityAURORA, Ore. – An Oregon State Universityresearcher aims to lower production costs forgrowers by creating a new kind of blueberry thatdevelops as a tree instead of the traditionalbush.Wei Qiang Yang, blueberry agent for theOregon State University Extension Service, hastested a grafted blueberry "tree" that grows on asingle stem on a research plot at OSU's NorthWillamette Research and Extension Center inAurora every year since 2009. Yang iscollaborating with researchers who are testingother blueberry varieties grafted onto rootstocksat land-grant universities in California andFlorida as part of a multi-state effort."The first rootstock that will come out of thisresearch for commercial use will significantlychange the way blueberries are currentlyproduced and harvested," said Yang, ahorticulture professor in OSU's College ofAgricultural Sciences.The research could benefit an industry that'seconomically important to Oregon. Theblueberry industry contributed 107.5 million insales to Oregon's economy in 2012, accordingto a report by the United States Department ofAgriculture and OSU Extension. Growersproduced 72 million pounds of blueberries onnearly 8,000 acres.Growers use machine harvesters with catchplates to collect blueberries, but becauseblueberry bushes have multiple stems, thecatch plate cannot fully encircle each stem ofthe bush. So growers must bear about a 15-25percent loss in terms of the fruit that the catchplate misses, according to Yang. But cultivatinga blueberry bush in a tree form would changethat, he said."This work isn't just academically important, butit's valuable from a practical standpoint in that itwill be very significant for improving machineharvesting efficiency and the adaptability ofblueberry plants to different soil conditions,"Yang said. "The wild-grown species is betteradapted to nutrient-poor and relatively high-pHsoil. If we're successful, this is going to changethe way we raise blueberries."To make the grafts, Yang started with seedsfrom a wild-growing blueberry plant commonlyknown as sparkleberry, which originated inTexas, Oklahoma and Florida. In the wild, someplants grow on a single stem to heights of up to10 feet. But their tiny berries are full of seedsand the fruit has a bad taste, Yang said. Hethen grafted three popular highbush blueberryvarieties – Liberty, Aurora and Draper – onto thewild-growing plants. He wanted a blueberryplant that had a similar yield to its domesticcousins and had a good taste.So far, yields of the grafted plants havecompared favorably to their domesticatedcousins, with the exception of Liberty. A graftedLiberty plant yielded an average ofapproximately 1.03 pounds of fruit per singletree, compared to an average of 1.68 poundsper single bush on a domesticated Liberty plant.A grafted Draper plant yielded an average ofapproximately 0.60 pounds of fruit per singletree, while a domesticated Draper plant yieldsan average of 0.55 pounds per single bush. Agrafted Aurora yielded an average of 1.07pounds of fruit per single tree, while adomesticated Aurora yields an average of 0.88pounds of fruit per single bush. Taste has alsocompared well.Yang must still analyze results of data collectedon fruit quality factors such as firmness, sizeand total acidity. This is the first yearresearchers were able to collect data on yieldfor the project in Oregon. Yang will investigate5

future yield projections and machine harvestingpotential next. If results continue to showpromise, the blueberry tree could be ready forrelease to nurseries in approximately five yearsfor commercial use and about three years forgardeners.Though some people have tried graftingblueberry trees on a small-scale basis in thepast, Yang said this is the first majorcollaborative research effort to graft a blueberrytree that is viable for commercial growers.Yang receives funding for the research from theOregon Blueberry Commission and the U.S.Department of Agriculture's Specialty CropsResearch Initiative.For more information, go to the website forOSU's NWREC athttp://oregonstate.edu/dept/NWREC.A Quick Review of Blueberry FlowerBud StagesD. Scott NeSmithThe University of GeorgiaOften times during blueberry presentations orwhen reading some of our managementguidelines, you might come across somethingreferring to blueberry flower bud stages. Arecommendation may instruct the user to applya compound at stage 6 of bud development, forexample. Or, you might hear someone say, “donot apply this compound after stage 4 of buddevelopment”. So, what is this referring too?Here is a brief overview of blueberry flower budstages, along with photos to help understandthe concept more clearly.A flower bud stage scheme was developedyears ago by Spiers (1978) to help designaterabbiteye blueberry sensitivity to cold damage.The stage designations we typically use inGeorgia today or more or less modeled afterthis. Having “stages” to describe buddevelopment helps in communication. It is toodifficult to instruct usage of management orpesticides with regards to “flowering time”, asthat often has varied meanings to differentpeople. Therefore, using bud stages todescribe progression of plant developmentimproves our ability to communicate.Especially, if we all refer to the same, or atleast a similar, bud stage scale.Following are updated photos of the differentstages of flower bud development, along withsome brief descriptions for each. Users haveto keep in mind this is a simple guide. Budscan be between stages just as easily as theyare at a “stage”. Once buds leave dormancy(stage 2), they progress, more or less,depending on heat units accumulated. So, oncold days buds advance very little, but when itwarms up buds advance very fast. Also, budsover the whole plant are at many differentstages at once (Fig. 1). Therefore, one cannotsimply designate a single stage to describe awhole plant or especially whole fields.Table 1 shows data from our work severalyears ago on sensitivity of two rabbiteyeblueberry varieties to sub- ‐freezingtemperatures at different stages of buddevelopment. Temperatures shown are the“T50 values”, which is the temperature atwhich 50% of the flowers examined showeddamage. These data remind us that althoughthere are some variety differences in coldhardiness (and typically highbush varieties aremore cold hardy than rabbiteye), overall, asflower buds advance they become moresensitive to freezing temperatures.We should all familiarize ourselves with “flowerbud stages”. Hopefully this review helps toremind us about the progression of flower buds,and the fact that floral bud stages are goodindicators for communicating what is happeningwith regards to plant development.ReferencesSpiers, J.M. 1978. Effect of stage of buddevelopment on cold injury in rabbiteye6

blueberry. J. Amer. Soc. Hort. Sci., 103: 452 ‐455.Stage 1: Dormant bud. Novisible signs of swelling.Note bud scales are verytight.Stage 3: Bud scalesnoticably seperated. Tipsof flowers beginning to bevisible.Stage 2: Visible bud swelling,scales starting to separate.Bud is leaving dormancy.Stage 4: Bud scales havedropped. Individual flowersdistinguishable. Bud has a“pineapple” look to it.Corollas beginning toelongate.Stage 7: Corollas have dropped. Pollination is over. A rapidcorolla drop often indicates good pollination has occurred.Especially if buds look to be more erect and less “droopy”.Figure 1: Various flower bud stages occur simultaneous overthe entire plant and field. Looking closely, flower bud stages 2through 6 can be seen on this one plant.Table 1: Temperatures at which 50% (T50 values)of corollas, styles and ovaries for ‘Brightwell’ and‘Tifblue’ rabbiteye blueberry varieties were damagedby freezing at various stages of floral development.Flower StageFlower PartCorollasStyles- ‐- ‐- ‐- ‐- ‐- ‐- ‐- ‐- ‐- ‐- ‐- ‐T50Ovariesvalues- ‐- ‐- ‐- ‐- ‐- ‐- ‐- ‐- ‐- ‐- ‐- ‐BrightwellStage 422.8 F21.9 F19.8 FStage 523.0 F22.5 F21.0 FStage 623.9 F23.4 F22.1 FStage 420.5 F22.6 F19.9 FStage 524.1 F23.7 F21.6 FStage 625.0 F23.2 F22.1 FTifblueStage 5: Individual flowersseparated, corollaselongated, but not yet open.Stage 6: Corollascompletely elongated,expanded, and open. Thisis the time when flower canbe pollinated.7

Chemical Gray Mold Control inStrawberries and Blackberries;Lessons from Four Years ofResistance MonitoringGuido SchnabelClemson UniversityGray mold is a disease that you can alwayscount on year after year. It is caused by afungus, Botrytis, which infects flowers in thespring and from there moves on to the fruit.Preharvest and postharvest losses of 5 to 20percent (depending on the year) are common.Protecting the flowers is the key to managingthis disease and that is accomplished primarilywith fungicides.Besides captan and thiram, there are fungicidesfrom seven different chemical classes availablefor gray mold control. They include FRAC(Fungicide Resistance Action Committee)groups 1, 2, 7, 9, 11, 12, and 17. They aretypically more effective and the risk towardconsumer, worker, and environment is muchless. But these benefits come at a price; allseven chemical classes are prone to resistancedevelopment. You might think that SEVEN kindsof fungicides would be enough to control graymold for the next 50 years or so, but thinkagain. We are dealing with a ‘high risk’ fungusthat is a champion among pathogens inadapting to stressful environments. Combinethat with the selective pressure we aresubjecting this fungus to (up to 15 applicationsper season) and you will begin to understandthe results of our region-wide resistancemonitoring that includes farms from manyeastern states stretching from Pennsylvania toFlorida. Some of the highlights include: There is resistance to all seven chemicalclasses out there. Luckily, we do notfind resistance to all fungicideseverywhere.The resistance profile, i.e. theresistance phenotypes present in apopulation, varies with the farm. Typically a farm that historically has notbeen sprayed very much will have theleast amount of resistance. From year toyear the resistance profile can change,influenced by fungicide choices in theprevious year and new Botrytis strainseither brought in with transplants ordrifting in from nearby inoculum sources.Resistance to FRAC 1 compounds (e.g.Topsin M; Fig. 1) is extremelywidespread and is a component ofvirtually all resistance genotypes we arefinding. For example, strains that areresistant to Elevate are always alsoresistant to Topsin M. That means whenyou spray Topsin M or any other FRAC 1compound you are selecting not only forincreased prevalence of Topsin Mresistance but also resistance toadditional compounds (in this example toElevate). Therefore, we do notrecommend FRAC 1 compounds anylonger for disease control instrawberry production.Our data also shows that FRAC 11compounds (Cabrio, Quadris), which hadsuppressive activity, have becomelargely ineffective against gray moldcontrol. That means when you spray acombination product such as Pristine orMerivon, only one active ingredient inthese mixtures (FRAC 7) works againstgray mold. The FRAC 11 component,which is active against anthracnose,does not have to be applied routinelyevery year. Instead we recommendreducing the risk of resistancedevelopment in the anthracnose fungusby only applying FRAC 11 products whenneeded. For routine gray mold controlFRAC 7 products should be used assolo formulations (e.g. Fontelis).Our current recommendation is to use captan orthiram prior to bloom if needed. During bloomuse captan during low disease pressure (during8

dry weather or during short rain events whentemperatures are less than 60 F). Use a mixtureof captan plus either FRAC 7 (e.g. Fontelis), 12(e.g. Switch), or 17 (e.g. Elevate) during bloomprior to major rain events (rain lasting more than12 hours at temperatures between 60 F and70F). Make sure you are getting at least 6 hrs ofdrying time.Our lab at Clemson offers a (still) freeresistance monitoring service that lets youidentify what FRAC group to use during bloomtogether with captan for optimal control. Formore information on sampling go latest-instructions-feb-26-2014/and download the 2014 Collection Instructions(1).Topsin MSensitive strainResistant strainFigure 1: While ‘normal’ Botrytis fungus can be effectivelycontrolled with Topsin M (upper berries), mutant field strainsresistant to Topsin M cannot be controlled even with highestlabel rates (lower berries).Winter Injury in CaneberriesGina Fernandez, NC State UniversityExtracted from a presentation to the NCCommercial Blackberry and Raspberry GrowersAssociation on February 6, 2014“Winter” injury, caused by cold temperatureshas different symptoms depending on the timeof year it occurs. The plant’s ability to withstandcold also varies through the year.In fall, early frost damages terminate fruitingon primocane fruiting cultivarsIn winter, very cold temperatures kill canes,damage rootsIn the late dormant season, fluctuatingtemperatures cause cane and/or bud damageIn spring, late frosts cause death of flowerbudsWinter injury may kill floricanes but not newprimocanes. Damage is not always apparentuntil fruiting laterals begin to grow.This year, our primary concern (at this date) isinjury that may have occurred in the winter andearly spring. We have seen temperatures fallbelow 0º F in the mountains of NC twice (1/7and 1/30/14) at the Mountain Horticultural CropsResearch Station in Mills River, NC. At thePiedmont Research Station in Salisbury, NC,temperatures were in the single digits on thosesame dates. These temperatures are belowwhat has been determined as criticaltemperatures for injury in blackberry (see charton previous page).In early February, we collected canes from ourresearch sites across the state. In general, wefound damage to blackberry buds collected fromthe mountains but not many from than in thosegrown in the piedmont region. This past week(mid March), I was in the coastal plain region ofthe state and did not see any damage toblackberry buds.Practices for Reducing Freeze DamagePlant on north-facing slopes to avoid fluctuatingwinter temperature effectsDelay pruning as long as possible; extremitiesare usually more susceptible to damage.Place row covers over RCA trellises berries toprotect western caneberry varieties in theMidwest.Avoid cultivation. Cultivation in late winter andearly spring tends to increase freeze damage.9

Soil temperature on a radiation-frost night willbe much warmer than air temperature, and if thesoil has been cultivated, the surface layer willcontain more air and less water. With lesswater, the surface layer will hold less heat. Also,the increased soil air will cause the surfacelayer to be a better insulator, which willdecrease the amount of heat released fromdeeper in the soil. Bushes will probably stay 1 to2o F warmer on uncultivated soil than oncultivated soil.Maintain soil moisture. By increasing theamount of water in the soil, the soil will absorbmore heat during the day and conduct moreheat to the surface for plant protection. Excesswater for extended periods must be avoided toprevent flooding or phytophthora root rotdamage. Sprinkler irrigation is notrecommended.Below are some examples of what to look forwhen dissecting caneberry buds.Southern Region SmallFruit ConsortiumAwards 108,851 in Grants for 2014Tom Monaco, Coordinator, SRSFCThe Steering Committee of the Southern RegionSmall Fruit Consortium (SRSFC)awarded 108,851 in research and extensiongrants at their annual meeting held January2014 in Savannah, GA.Seventeen research proposals totaling 84,351were funded and four extension proposals for atotal of 20,000 were funded. Also 4,500 wasawarded to the extension efforts in updating theIPM/Production Guides.The IR4 Performance program provided a halfmatch to three research proposals which added 7,500 in additional funding so the total amountfunded for 2014 was 116,351Research and Extension projects funded for2014 can be viewed 014.htmlRetail Demand for Fresh BerriesThe cold temperatures have permanently damaged this Navahobud. Notice that in the center of this bud there is a dark dot(necrosis). This will not produce fruit in the spring.Photo: Gina FernandezMichael R. ThomsenAssociate Professor, Dept. of AgriculturalEconomics and AgribusinessUniversity of Arkansas, Fayetteville, AR USAReprinted with permission from The Bramble,Spring 2014, the newsletter of the NorthAmerican Raspberry & Blackberry Association.For more information visitwww.raspberryblackberry.comThis picture is a great example of healthy Navaho bud. Noticethat the bud looks green and there are no signs of necrosis.Photo: Nicholas BasingerAgricultural economists at the University ofArkansas have examined retail demand forfresh berries. The goal is to improveunderstanding of consumer sensitivity to prices10

and retail competition among different types ofberries. Results show that the demand for eachberry is highly responsive to changes in its ownprice.Dr. Thomsen spoke about this topic at the2013 Berry Health Benefits Symposium.See www.berryhealth.org.Responsiveness of retail berry demands to pricePromotion of health benefits is sensible giventhese findings because it reduces pricesensitivity by making other fruits lessappealing substitutes. Because ber- ries aresubstitutes, promotional efforts that raise theprice of one type of berry are likely to createpositive spillovers to competing berries.tBlueberriesDemand iesPrice of:Supermarkets offer many fresh fruits, most ofwhich can serve as substitutes for berries toone degree or another. The easy access tosubstitute fruits is the main reason why freshmarket demand for each type of berry is priceresponsive. There are, however, importantdifferences among the different berries.Strawberries and blueberries are the leastprice responsive, with demand falling by 1.26%and for every 1.49%, respectively, for each 1%increase in the retail price. Consumers canreasonably expect to find fresh strawberries allyear and so strawberries are likely to be aplanned purchase item on consumer shoppinglists. Blackberries and raspberries, on the otherhand, are the most responsive. Blackberrydemand falls by 1.88% for every 1% increasein retail price. Relative to strawberries andblueberries, year-round access to freshblackberries is more recent and so black- berrydemand is likely to still be tied to impulsepurchases, which are sensitive to perceptionsof a good deal. Blackberry demand is also themost responsive to the prices of competingberries. For example, if the price ofstrawberries increases by 1% blackberrydemand increases by 0.52 percent indicatingthat consumers that may have been planningto buy strawberries switch to blackberrieswhen con- fronted with higher strawberryprices.Numbers in the table indicate the percentage change in volumedemanded resulting in price.Numbers that are larger in absolute value indicate a degree ofprice sensitivity.POSTHARVEST KITS FOR FRUITQUALITY TESTINGPenelope Perkins-Veazie, NC State UniversityReprinted with permission from The Bramble,Spring 2014, the newsletter of the NorthAmerican Raspberry & Blackberry Association.For more information visitwww.raspberryblackberry.comPostharvest experts generally follow fruit andvegetables from field to consumer. The generalguidelines are cleanliness, cold chainmanagement, adherence to packagingguid

James Cooley Named Swisher Sweets/Sunbelt Expo Southeastern Farmer of the Year for 2013 James Cooley is a member of the SRSFC Steering Committee First published online - Sunbelt Ag Expo, October 15, 2013 (Moultrie, Ga.)— South Carolina peach and strawberry grower James Cooley, who built a beautiful farm that has become an agricultural tourism