Mnging Soilborne Diseses Through Removl of Root Inoculum in Red Rspberry L.W. DeVetter1, I. Zsd2, J. Weilnd2, T. Wlters3, R. Rudolph4, S. Wtkinson5, Mrk Mzzol6, nd Suzette Glinto7 1Assistnt Professor, Smll Fruit Horticulture, Wshington Stte University Northwest Reserch Extension Center (WSU-NWREC) in Mt. Vernon, WA, 2Reserch Plnt Pthologists, USDA-HCR Unit in Corvllis, OR, 3Agriculturl Resercher, Wlters Ag Reserch, Ancortes, WA, 4Grdute Student, WSU-NWREC, 5Scientific Technicin, WSU-NWREC, 6Reserch Plnt Pthologist, USDA-TFR Unit in Wentchee, WA, nd 7Economist, WSU School of Economic Sciences, Pullmn, WA
Red Rspberries in Wshington Wshington is the lrgest ntionl producer of processed red rspberries In 2014, 73 million pounds of fruit were hrvested from 9,700 cres Vlued t ~$60.9 million in 2014 Depending on yer, 59-88% of totl US red rspberry crege is in Wshington Source: NASS, 2015 nd WRRC, 2015
Industry Chllenges Fields tht used to remin in production for 15-20+ yers re now being renovted nd replnted every 5-8 yers Lnd suitble for red rspberry is limited, so production is often continuous nd crop rottion seldom used Soils re typiclly fumigted prior to replnting
Soil Fumigtion in Red Rspberry Preplnt fumigtion in fll or spring Fumignts typiclly pplied by commercil pplictors Most fumignts re deep-shnked nd injected into the soil t depths of 12-18 inches; untrped Primry fumignt products: Telone C-35-1,3-dichloropropene (63.4%) + chloropicrin (34.7%) Vpm - metm sodium (42%)
Despite Fumigtion, Soilborne Disese Mngement is Still Mjor Chllenge for the Red Rspberry Industry Chnges in lnd mngement Loss of trditionl soil fumignts Incresing restrictions on fumignt usge Appliction methods need optimiztion Concerns over soil qulity, especilly soil biology Poor understnding of replnt disese
Soilborne Pthogens nd Pests Phytophthor rubi Oomycete wter molds Cusl gent of Phytophthor root rot Oospores nd myceli cn persist in soils for yers Infection of root tissue dmges root systems Imge: forestpthology.cfns.umn.edu Imge: psnet.org Prtylenchus penetrns Root-lesion nemtode Migrtory endoprsite with brod host rnge High popultions cn cuse root diebck, stunting, nd increse the potentil for synergistic disese complexes
SFH Reserch Gols One of the primry gols of the Smll Fruit Horticulture (SFH) progrm is to develop improved horticulturl tools for soilborne disese mngement in red rspberry Improved soilborne disese mngement is shred gol nd offers excellent opportunity for collbortion Diverse pproch: Alterntive fumignts nd methods of fumigtion Appliction nd mngement of cover crops Improved understnding soil microbil ecology nd replnt disese Removl of root nd crown inoculum
Why Root nd Crown Removl? Lrge mounts of root nd crown mteril remin in fields prior to fumigtion nd replnting Soil fumignts re unble to penetrte undecomposed plnt mteril Remining plnt mteril could serve s source of inoculum for soilborne diseses nd pests
Plnt Mteril Remining in Field Prior to Fumigtion
Gols of Root Removl Project Short Term Evlute nd demonstrte the efficcy of rspberry root inoculum removl s pre-plnt mngement technique for reducing soilborne pthogen nd pest popultions Long Term Develop prcticl tools for the integrted mngement of soilborne pthogens nd pests Two experiments
Experiment 1 Objective: Compre three root removl devices for speed nd efficcy of root removl in two commercil fields Economic nlysis with Mrs. Glinto Devices tested includes: Lundby plnt lifter Bech clener Potto hrvester
Evluted Tools for Rspberry Root Removl Lundby Plnt Lifter Bech Clener Video: https://www.youtube.com/wtch?v=vnn0h8jroa4 Potto Hrvester
Experiment 1 - Results Device Speed (mph) Percent of root nd crown mteril removed z Plnt lifter 0.25 98 Bech clener 0.37 91 Potto hrvester 1.0 96 Z Determined by mesuring the mount of removed root/crown mteril within 4 ft 3 (0.1 m 3 ) of soil.
Volume of Mteril Removed Amount of root mteril removed (left) nd remining (right) in 4 ft 3 plot.
Experiment 2 Objective: Evlute the effects of root removl on: 1) Popultions of soilborne pthogens nd pests 2) Rspberry plnt growth, development, nd yields Initited in Cheminus field replnted to Meeker in Aug. 2014 in Whtcom County, WA
Experiment 2 Approch Split plot experiment Min plot: Fumigtion, with or without using Telone C-35 t 32 gl/cre Split plot: Root removl (with or without removl, using Lundby plnt lifter) Replicted six times Min plots were 100 x 30 ft nd the split plots 15 x 30 ft in size Dt to be collected includes: chnges in soilborne disese (Fusrium nd Pythium, proxies for P. rubi) nd P. penetrns popultions, plnt growth, nd yield
Experiment 2 Preliminry Results 6000 5000 4000 Fum + Roots Fum - Roots Nonfum + Roots Nonfum - Roots Pp/g root 3000 2000 1000 0 Mrch April My June July Aug. Sept. Oct. Month (2015) Chnges in P. penetrns popultions over time, 2015. Popultions returned to pre-fumigtion levels by Aug. 2015.
Experiment 2 Preliminry Results b b Pretretment Post tretment (6 weeks) Preplnt Chnges in Pythium popultions s result of root removl nd fumigtion tretments, 2015. Results similr for Fusrium. *Figure courtesy of Dr. Weilnd
Experiment 2 Preliminry Results Pretretment Post tretment (6 weeks) Preplnt Chnges in Fusrium popultions in root mteril > 5 mm in dimeter over time, 2015. Results similr for Pythium. *Figure courtesy of Dr. Weilnd
Experiment 2 Preliminry Results 25 Men cne no. hill 20 15 10 No differences in cne number per hill nor cne height s of June 2015 Re-evlute in 2016 5 0 Fum + roots Fum - roots Nonfum + roots Nonfum - roots Tretment 70 60 Men height (cm) 50 40 30 20 10 0 Fum + roots Fum - roots Nonfum + roots Nonfum - roots Tretment
Next Steps for Root Removl Projects Continue monitoring Collect first set of yield dt Repet experiment in field site infested with P. rubi
Root removl genertes lrge mount of wste Is composting vible disposl method for removed root/crown mteril?
Composting Experiment Tissue culture Meeker plnts were grown in compost, with nd without roots Removed roots were composted nd screened for P. penetrns, Fusrium, nd Pythium vi greenhouse biossy Composting reduced pests nd pthogens to undetectble levels Economic vibility?
Thoughts Moving Forwrd Imge: www.whtcom.wsu.edu Conventionl fumigtion = unstisfctory results Concerns tht overwintering cover crops my serve s bridge for P. penetrns Trils with biofumignts (Dominus ) nd metm sodium show promise New reserch funded by WSDA SCBG ddress these timely concerns
Acknowledgements Co-PIs: Ing Zsd, Jerry Weilnd, Tom Wlters, Suzette Glinto, nd Mrk Mzzol Sen Wtkinson, SFH Technicin Chris Benedict, Whtcom County Extension Rchel Rudolph, Grdute Student Rchel Weber nd Jck Pinkerton Grower coopertors, especilly Jon Mberry nd Rndy Honcoop Smit s Compost Tim Purcell, Trident Agriculturl Products Whtcom Frmers Co-op Northwest Center for Smll Fruits Reserch
Thnk you for your ttention! Lis Wsko DeVetter, PhD Smll Fruit Horticulture Progrm Wshington Stte University NWREC Emil: lis.devetter@wsu.edu Any questions?