Tools to manage soilborne diseases Aad Termorshuizen Joeke Postma http://floragrubb.com/florasblog/?p=894 Speaker's name Meeting and date
Common soilborne pathogens ❶ ❷ Protozoa (Protoctista, Rhizaria) pathogen / disease ❶ Plasmodiophora brassicae/club root ❷ Polymyxa betae/rhizomania hosts / survival time Brassica/>15 yrs sugar beet/>15 yrs ❸ Chromista ❸ Pythium spp./damping-off ❹ Phytophthora spp./root rot Fungi ❺ Rhizoctonia solani/root rot ❻ Fusarium oxysporum/root rot, wilt ❼ Verticillium dahliae/wilt ❽ Synchytrium endobioticum/wart Nematoda ❾ Meloidogyne spp./root knot ❿ Globodera rostochiensis/potato cyst many/1-2 yrs many/>4 yrs many/1-4 yrs many/10-15 yrs many/>4 yrs potato/>20yrs many/1-4 yrs potato/4 yrs ❹ ❺ ❻ ❾ ❿ ❽ ❼
low pesticide availability Current agricultural practices create opportunities for soilborne pathogens organic matter management economic pressure rotation low organic matter systems specialisation declined disease suppression avoidance - hygiene - rotation biological control increase of soilborne pathogens narrow rotations physical control: - heating - anaerobiosis -
root knot in carrot Hygienic measures (avoidance) most soilborne pathogens have no airborne dispersal avoidance of novel infestations Agrios, Plant Pathology
Pathogen avoidance by designed rotations damage (color) pathogen multiplication pathogen host
Green manure cropping to manage soilborne diseases Tagetes suppresses Pratylenchus >5 yrs Pratylenchidae (#/100 ml soil) 900 800 700 control Tagetes patula 600 500 400 300 200 100 0 mrt-06 mrt-07 mrt-08 mrt-09 mrt-10 mrt-11 mrt-12 mrt-13 mrt-14 mrt-15 Johnny Visser
Biological control Sufficient candidates but introduction in practice is problematic: allowance & registration costs (also with applying mixtures of bca s) persistence of effects versatility under varying conditions (crops, climates, soils )
Bernard et al., 2014, Plant Soil 374:611 Biological control compared with other methods Black Scurf (Rhizoctonia solani) 2007 2008 2009 B. subtilis 0/0 0/0 -/0 T. virens +/0 0/0 0/0 R. solani-hy +/0 0/0 0/0 compost +/0 -/- -/- rapeseed +/+ 0/+ Common Scab (Streptomyces scabies) B. subtilis 0/0 0/0 0/0 T. virens +/0 0/0 +/+ R. solani-hy 0/0 0/0 +/+ compost -/0 -/- 0/- rapeseed +/+ 0/+ Silver Scurf (Helminthosporium solani) B. subtilis 0/0 0/0 0/0 T. virens 0/+ 0/0 0/0 R. solani-hy 0/0 0/+ 0/0 compost 0/0 -/0 -/- rapeseed +/+ 0/+ 0 = no effect, - = disease stimulation, + = disease suppression
disease suppression (%) Yes, organic matter amendments can help to increase disease suppression, but not allways 150 Rhizoctonia solani (c.) Verticillium dahliae Phytophthora cinnamomi Fusarium oxysporum Cylindrocladium spathiphyllum Rhizoctonia solani (p) 100 50 0 utrecht -50 dec01 dec02 co16 co2 bom 8.1s 1.02s co7 gr3a gr5 1.02ba isbs gr3b co14 co17 co4 gr6-100 Termorshuizen et al., Soil Biol. Biochem. 38: 2461 compost Gera van Os
Anaerobic soil disinfestation (ASD) Incorporation of ±24 t/ha organic material into soil Covering the soil with airtight plasticincubation for 2-3 weeks; application in summer Control of a.o. Globodera, Pratylenchus and Meloidogyne comparible to application of nematicides Also control of a.o. Sclerotinia, Verticillium and Fusarium Costly (OK for cash crops, e.g. strawberry, asparagus)
Effects on pathogens depend on their density Disease incidence Disease incidence Fusarium / onion 10 microsclerotia / g soil cultivar 10000 microsclerotia / g soil Days after sowing
Conclusions If single tools are available, they are, generally, too expensive Methods for early detection are not adopted (expensive) or unavailable, thus hampering early actions For the short term, rotation is still the most fruitful option Smart designs combining various tools are the future
Thank you for your attention! Aad Termorshuizen & Joeke Postma The research leading to these results has received funding from the European Union Seventh Framework Programme (FP7/ 2007-2013) under the grant agreement n 265865- PURE
Speaker's name Meeting and date
relative sugar beet yield Sugar beet yield indicators sugar yield (ton ha -1 ) s Heterodera sp. 1 s BNYVV 1 s Aphanomyces cochlioides 1 soil structure, e.g. porosity * 2 sowing date 1 # fungicide applications 1 Dorylaimoidea 3 Clay *** *** *** *** - * * Sand ** - - *** * * *** - 1 Hanse et al., 2011, Crop Prot. 30:671 2 Hanse et al., 2011, Soil Till. Res. 117:61 3 Termorshuizen & Hanse, unpub. theoretical yield 25 20 15 10 5 0 sand clay Dorylaimoidea (# / 200 ml soil) average top growers
sugar beet yield (ton/ha) Dorylaimoidea
Ziektewering varieert (1) ID-DI relationship and antagonists: Fusarium moniliforme / maize / Streptomyces sp.
Effect of management actions is dependent of pathogen density organic matter application