Outline Problem pests of strawberries (& how to manage them) Alberta Farm Fresh School 207 Olds, AB 2 significant strawberry pests Either present or threatening For each Life/Disease Cycle Symptoms Monitoring / Environmental COnditions Management Anthracnose ANTHRACNOSE Colletotrichum fragariae C. acutatum C. gloeosporioides Different species can cause different diseases Crown rot Fruit rot Leaf spots Affects foliage, runners, crowns and fruit Anthracnose SYMPTOM C. acutatum C. fragariae C. gloeosporioides Crown rot X Fruit rot X X X Black leaf spot X X Irregular leaf spot X Information courtesy www.fruit.cornell.edu Disease Cycle Typically introduced in infected plants Can overwinter for a short time (up to year) on debris Spores are produced in warm, humid weather Spread by rain splash or irrigation Spores may also be transferred by clothing and equipment Wetness is required for infection
Occur on green or ripe fruit Brown or black, sunken lesions Tend to be small (typically less than.5cm across) In humid conditions Salmon (pink orangey) coloured ooze (filled with spores) is released from lesions Anthracnose lesion on fruit Dark, sunken lesions form on petioles, runners and crowns Daughter plants may die Outer leaves may die prematurely Anthracnose lesion on fruit Anthracnose lesion on leaf petiole Anthracnose sunken elliptical lesion on runner 2
Plants may collapse from crown rot Crowns may exhibit a reddish brown streaking when cut lengthwise Looks a bit marbled Dried up, dead flowers or small, hard dried up fruit may be observed if infections occur during flowering Symptoms of anthracnose crown rot Photo by Frank Louws, North Carolina State University Crown discolouration from Anthracnose or Phytophthora Photo by OMAFRA Telling the difference between Anthracnose & look a likes Look a like Disease Botrytis Grey Mold Leather Rot Verticillium Wilt Phytophthora Crown Rot Symptoms Fruit lesions often associated with the calyx Lesions develop grey fuzzy mould and grey spores Indistinct lesions Smell foul Spores that develop are white Wilted plants, but crowns do not have the reddish discolouration Plants wilt Crowns have reddish discolouration Conditions Favouring Disease Development Very weather dependent Splashed rain Warm, humid conditions 20 2 C and 00% RH Start with clean plant material Some varieties have resistance (most don t) Practice good sanitation Remove infected fruit from the field Clean up crop debris between crops Clean equipment between fields
Maintain a good rotation between non host crops Control weeds Some weeds may be hosts Work in infected fields last Clean clothing and equipment after working in infected fields Spores can survive on clothing for several weeks Avoid over fertilizing plants, specifically Nitrogen Vigorous plants are more susceptible Ensure a good layer of straw is in place Straw reduces rain splash and disease spread Use drip irrigation instead of sprinklers Apply registered fungicides, where appropriate Registered s (for control of Anthracnose) Actinovate SP 28672 425g / 00L H 2 O / ha Streptomyces lydicus strain WYEC 08 x0-7 CFU/g Novozymes BioAg Ltd. Begin when conducive to disease development 7-4 days Foliar spray; spray to wetness Cabrio EG 272 Pyraclostrobin 20% BASF 0.56 kg/ha No later than 7-4 days Registered s (for control of Anthracnose) Evito 480SC 0408 46-280 ml/ha Fluoxastrobin 480g/L 4 apps;.2l/ha/year Arysta LifeScience NA LLC 0 Begin apps preventatively 4-2 days Pristine WG 27985 boscalid 25.2% pyraclostrobin 2.8%..6 kg/ha 5 BASF 24 hours (or dried residues) Begin applications no later than 0% 7-4 days TARNISHED PLANT BUG 4
Lygus lineolaris A.K.A. Lygus Bug Tarnished Plant Bug Tarnished Plant Bug nymph (Photo Courtesy MAFRD) Distinctive Triangle Marking One of the most serious & widespread of strawberry pests Wide range of host plant species Tarnished Plant Bug adult Tarnished Plant Bug nymph & adult on fruit Tarnished Plant Bug adult (Photo Courtesy MAFRD) Tarnished Plant Bug adult on flowers Tarnished Plant Bug adult on fruit Feeding by nymphs Nubbins or deformed fruit Apical seediness Adult feeding CATFACING Catfaced berries Tarnished Plant Bug damage on fruit damaged seeds NOTE: Catfacing can be caused by other factors, producing identical symptoms 5
Monitoring Catfaced berries caused by a range of factors Scout the field perimeter in new fields or entire established fields Survey the field from pre until green fruit stage Tap plants or shake fruit clusters over a nonmetallic pie plate Count the number of nymphs per 00 clusters Economic threshold = nymph per inflorescence (strawberries) Careful monitoring of TPB populations Remove weeds (especially leguminous species) Ensure alternate host crops are not planted too close to field / orchards (e.g. alfalfa) Timely application of registered chemicals Registered s (for control of TPB/Lygus Bug) Rimon 0EC 5 2888 / 2855 novaluron 0% 85mL/ha (in 450-400L H 2 O) McDeramid Agricultural Solutions Canada Co. / Adama Agricultural Solutions Canada Ltd. Make first app when economic threshold reached 0 4 days Target nymphs; Ensure thorough coverage Registered s (for control of TPB/Lygus Bug) Cygon 480AG/EC / Lagon 480E B 2565 / 9807 / 982 / 8277 2.75L/ha (.25L/000L H 2 O) dimethoate 480g/L 2 FMC Corp / Interprovincial Co-op / Loveland s / Cheminova 7 2 days st app when s first appear 0-2 days Avoid applying when bees active (during ) apply in evening Registered s (for control of TPB/Lygus Bug) Clutch 50WDG / 2982 / 2984 Clothianidin Insecticide 4A Assail 70WP 4 448g/ha (min. 500L/ha H 2 O) 2728 84-20g/ha (min. spray volume of 87L/ha) clothianidin 50% acetamiprid 70% 2 Valent Canada Inc. Prior to start of N/A Ensure thorough coverage Nippon Soda Co. 2 hours Begin apps when economic thresholds are reached 7 days Ensure thorough coverage 6
Registered s (for control of TPB/Lygus Bug) Beleaf 50SG 9C Matador / Silencer 20EC / Warrior 29796 0.20kg/ha (min. 90L H 2 O/ha) 24984 / 29052 / 2687 Flonicamid 50% lambdacyhalothrin 20g/L / 20g/L / 22g/L 04mL/ha ISK Biosciences Corp 0 Apply prior to appearance in field; 7 days Also registered for greenhouse strawberries Syngenta Canada / Adama Agricultural Solutions Canada Ltd. / Syngenta Canada 7 24 hours 7-0 days after st 7-0 days Registered s (for control of TPB/Lygus Bug) Ripchord 400EC / UP-Cyde 2.5EC / MAKO / Ship 250EC 578 / 28795 / 06 / 256 250mL/ha (00-500L H 2 O/ha) / 400mL/ha / 400mL/ha cypermethrin 407g/L / 250g/L / 407g/L / 250g/L (2 for TPB) BASF Canada / United Phosphorus Inc. / Engage Agro Corp. / Sharda Cropchem Ltd 7 2 hours Apply at early (approx. 0%) / First 0-2 days / 7-0 days / 0-2 days / 7-0 days Geared to JB QUESTIONS??? Rob Spencer, BSA, MSc, P.Ag. Commercial Horticulture Specialist robert.spencer@gov.ab.ca Alberta Ag Info Centre 0 FARM 7