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In This IssueCrop ConditionsWatch for Dicamba Drift in Fruit CropsTissue Analysis for Small Fruit and GrapesJapanese BeetlesGlomerella Leaf BlightSuccessful Summer Field Day at GarwoodsUpcoming Events

Crop Conditions(Peter M Hirst, hirst@purdue.edu, (765) 494-1323) & (BruceBordelon, bordelon@purdue.edu, (765) 494-8212)

Fruit set in primocane fruiting blackberries

Bunch closure in grapes

GoldRush apple fruit approx. 2” diameter

Watch for Dicamba Drift inFruit Crops(Bruce Bordelon, bordelon@purdue.edu, (765) 494-8212)

By now almost everyone has heard aboutdicamba, the volatile growth regulator herbicidethat has garnered so much attention the pastcouple of years. It is being used over the top ofdicamba-tolerant soybeans on thousands of acresin the state this year. We are trying to keep trackof off-target damage so we would like to hearfrom growers that see any typical symptoms.Grapes are one of the most sensitive crops todicamba, though there is a wide range ofsensitivity among varieties. But they are not theonly fruit crops that are sensitive. Raspberries,blackberries, blueberries, and tree fruit are alsosensitive. Dicamba typically causes upward leafrolling on new growth (see pictures below). If yousee this type of damage in your fruit plantings,please contact your local Purdue ExtensionEducator or one of the specialists that write thisnewsletter. The more we know about the extent

Issue: 18-08July 5, 2018

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of damage, the better we can advise regulatorson reducing off-target movement.

Typical upward leaf rolling on new grape growthindicative of exposure to dicamba herbicide

Dicamba damage in black raspberry

Dicamba damage on Ouachita blackberry

Tissue Analysis for Small Fruitand Grapes(Bruce Bordelon, bordelon@purdue.edu, (765) 494-8212)

Plant nutritional status is important for all phasesof plant growth and has a direct effect on vigor,fruitfulness, cold hardiness, and other factors.Tissue analysis is the most reliable means ofdetermining plant nutritional status. Combinedwith soil testing, tissue analysis can help pinpointthe source of problems and determine whatmeasures may be needed to insure propernutrition of the crop. Tissue analysis samplesshould be collected at the appropriate time togive the most meaningful results.For strawberry, sample the first fully expandedleaves after renovation, usually in mid to lateJuly. For brambles, sample leaves on non-fruitingcanes (primocanes) between August 1 and 20.For blueberries sample leaves during the firstweek of harvest. For grapes, samples should betaken about 70 days after full bloom, usuallyearly to mid August. Samples should be adequatein size. Collect 30-60 leaves for strawberries,brambles, and blueberries, and 100 leaf petiolesfor grapes (for grapes submit only the leafpetiole, or stem, for analysis, discard the leafblade). Collect samples to represent the entirefield, not just from a few plants. Sample differentvarieties separately. If specific problems exist,collect separate samples from both normal andproblematic areas of the planting. Aftercollection, leaves should be rinsed gently in tapwater to remove any pesticide residues and dustthat might affect analysis, laid out to dry for acouple of days, then bagged in paper bags forsubmission to the lab. Some labs offer tissueanalysis sample kits.There are several private companies and a fewuniversities that provide tissue analysis. A list ofcertified soil and plant analysis testing labsserving Indiana growers is located at

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https://ag.purdue.edu/agry/extension/Pages/soil_testing.aspxThe Midwest Small Fruit Pest ManagementHandbook has a chapter on tissue analysis andfertilizer recommendations.https://ag.purdue.edu/hla/Hort/Documents/Midwest%20Sm%20Fruit%20861%201-24-11.pdf. Isuggest growers refer to that chapter whenreviewing tissue analysis results andrecommendations.

Japanese Beetles(Bruce Bordelon, bordelon@purdue.edu, (765) 494-8212)

Japanese beetles appear to be especiallyabundant this year. They started showing up acouple of weeks ago and are now numerous inmany areas. This past year Japanese beetlepopulations were higher than they have been fora number of years and this year looks to be arepeat. We’ve seen severe damage to smallfruits, grapes, as well as the Pristine apples,plums, etc. Adult beetles are relatively easy tocontrol, but after insecticide treatment to knockthem down, populations reappear as theinsecticide wears off. So, it may require morethan one application to control them. Sevin andthe pyrethroids will provide the best control,although Sevin may only give about 3 days ofprotection. Watch pre-harvest intervals (PHIs) insmall fruits if harvest is on-going. And note thatthe REI for Sevin can be 2 to 6 days in grapes.One note about damage: It often looks a lotworse than it really is. Beetles tend tocongregate along edge rows or row endsadjacent to grassy areas. Don’t assume thepickup truck view of the planting isrepresentative of the entire acreage. Anotherissue is that Japanese beetles feed primarily onthe upper leaves of most plants. Grapes canwithstand a significant amount of defoliation

without significant loss of yield or fruit quality.The same can be said for apples and other treefruit. However, in some cases the damage canresult in direct loss of yield or fruit quality.Raspberries can be severely affected byuncontrolled feeding. And in some crops, such asprimocane fruiting blackberries, Japanese beetlesfeed directly on flowers, reducing potential yieldconsiderably. In blueberries and peaches theyfeed directly on ripening fruit leading to a directloss of yield and reduction in fruit quality. Get outof the truck and scout your planting today!

Japanese beetle feeding damage in red raspberry

Japanese beetles on red raspberry

Japanese beetles feeding on PF blackberryflowers

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Japanese beetle feeding damage in grapes

Glomerella Leaf Blight(Janna L Beckerman, jbeckerm@purdue.edu, (765)494-4628)

Glomerella leaf blight seems to be rearing itsugly head. Symptoms include lesions withconcentric rings in them that can grow togetherand give the leaf a blighted appearance (Fig. 1).Leaves may yellow and fall off (Fig. 2) and mayappear like Golden Delicious necrotic leaf blotchon a variety of apple cultivars (Fig. 3).

Figure 1. Radiating bands within the lesions are acharacteristic of Glomerella. Photo by Janna

Beckerman

Figure 2. Significant leaf drop can affect somevarieties. Shown here is ‘Princess’, which is

almost defoliated by the most recent outbreak.Note fallen mummies and thick, weedy

undergrowth. Photo by Janna Beckerman

Figure 3. This pathogen can be mistaken forGolden Delicious necrotic blotch. Photo by Janna

Beckerman

Before anyone panics, Glomerella is not a newpathogen, but the sexual state of a fungus thatwas first identified it its asexual state and wasnamed Colletotrichum. Fungi known to infectapples and belonging to this group (genus) causebitter rot. Previously, the bitter rot pathogenswere divided into two species complexes: C.acutatum and C. gloeosporioides. Recent work inKentucky found five different species ofColletotrichum associated with bitter rot: C.fioriniae, C. nymphaeae, C. siamense, C.theobromicola, and C. fructicola. The relationshipbetween bitter rot and Glomerella leaf spot, ifany, is not all that clear here in Indiana. Oranywhere.Colletotrichum species are cosmopolitan fungi(by this, I mean they grow everywhere, not thatthey are found in vodka-based drinks) and infectalmost everything (fruit, vegetables, flowers,etc.). It isn’t clear if the fungi that infect leavesalso infect fruit on the tree, but we do know thatthey are all capable of causing post-harvest roton wounded fruit in storage.For now, keep your eyes peeled and below is alist of fungicides that are effective in controllingthis disease, provided applications are made toprotect growing fruit and that fungicides arereapplied after rain events that provide morethan 1-2 inches of precipitation. At Meigs, treesthat had better pruning and increased air flowhad less Glomerella than overgrown trees.

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Trade Name Active ingredient Pre-harvest interval -PHI (days)FRAC CodeRoper, Koverall Mancozeb 77 (3 lb/A rate only) M3Flint 50WG Trifloxystrobin 14 11Luna Sensation Trifloxystrobin + Fluopyram 14 11+7Ziram DF Ziram 14 M3Merivon Pyraclostrobin + Fluxapyroxad 0 11+7Pristine WG Pyraclostrobin + Boscalid 0 11+7Captan 80WDG Captan 0 M4

Successful Summer Field Dayat Garwoods(Peter M Hirst, hirst@purdue.edu, (765) 494-1323)

Thanks to all members of the Garwood familyand staff who hosted us for the summer field daylast week. Growers were inspired by the excellentjob Garwoods do with fruit and vegetableproduction and marketing. The fruit, vegetableand farm marketing industries in the state werewell represented, and all in attendanceappreciated members of the Garwood familysharing their many successes and a fewchallenges along the way. Thanks to Brian and allmembers of the Garwood family and staff fortheir hospitality.Sincerely,Peter Hirst

Upcoming Events(Lori K Jolly-Brown, ljollybr@purdue.edu)

July 17-18, 2018 Indiana Winery andVineyard Association Summer Meeting Brown County Inn, Nashville, INContact https://indianawinevine.org/events toregisterAugust 30, 2018 Small Farm Education FieldDay Purdue Daniel Turf CenterContact Lori Jolly-Brown, ljollybr@purdue.eduor 765-494-1296Register here: http://www.cvent.com/d/hgqx6gSeptember 5, 2018 Greenhouse & IndoorHydroponics WorkshopPurdue University, PFEN 1159 & PurdueHorticulture GreenhouseContact Lori Jolly-Brown ljollybr@purdue.eduRegister here: https://tinyurl.com/yaxd4k2zOctober 17, 2018 Indiana Flower GrowersConferenceDaniel Turf CenterContact Lori Jolly-Brown ljollybr@purdue.eduJanuary 8, 2019 Illiana Vegetable GrowersSymposiumTeibel’s Family Restaurant, Schererville, INContact Liz Maynard emaynard@purdue.eduhttps://ag.purdue.edu/hla/Extension/Pages/IVGS.aspxFebruary 12-14, 2019 Indiana HortCongressIndianapolis Marriott East Indianapolis, INContact Lori Jolly-Brown, ljollybr@purdue.eduor 765-494-1296http://www.inhortcongress.org

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Facts for Fancy Fruit © Purdue University - fff.hort.purdue.eduEditor: Peter M Hirst | Department of Horticulture and Landscape Architecture, 625 Agriculture Mall

Dr., West Lafayette, IN 47907 | (765) 494-1323