APPENDIX 3: Sources of Inoculum for Crop Diseas...

APPENDIX 3: Sources of Inoculum for Crop Diseases in the Northeastern United States

APPENDIX 3: Sources of Inoculum for Crop Diseases in the Northeastern United States

Compiled by Margaret Tuttle McGrath

Disease Pathogen Name Rotation (years)1 Seed Borne Wind- blown Spores2 Insect Vectored Weed Hosts
VEGETABLE CROPS
Asparagus
Fusarium crown rot Fusarium spp. Y (long) Y (crown) N N wide host range3
Fusarium root rot Fusarium spp. Y (long) Y (crown) N N wide host range3
Phytophthora spear rot Phytophthora spp. N Maybe N N common purslane, horsenettle, velvetleaf, eastern black nightshade (P. capsici)
Rust Puccinia asparagi Y (3) N Y N no records located
Bean, snap and dry
Anthracnose Colletotrichum lindemuthianum Y (3) Y Y (local, rain) N no records located
Bacterial brown spot Pseudomonas syringae pv. syringae Y (2) Y NA N wide host range
Bean common mosaic virus (BCMV) Bean common mosaic virus (BCMV) NA Y NA Y (aphid) common chickweed, common lambsquarters, black medic, Canada thistle
Bean rust Uromyces appendiculatus Y (3) N Y N no records located
Bean yellow mosaic virus (BYMV) Bean yellow mosaic virus (BYMV) NA N NA Y (aphid) many, mostly legumes7
Botrytis gray mold Botrytis cinerea Y N Y N common sunflower
Clover yellow vein virus (CYVV) Clover yellow vein virus (CYVV) NA N NA Y common lambsquarters, black medic, clover, and possibly other perennial weeds
Common bacterial blight Xanthomonas campestris Y (2-3) Y NA N mustard, shepherd's purse, some other weeds in the mustard family, soybean
Cucumber mosaic virus (CMV) Cucumber mosaic virus (CMV) NA Y NA Y (aphid) wide host range8
Halo blight Pseudomonas syringae pv. phaseolicola Y (3) Y NA N wide host range
Root rot, damping-off Pythium, Rhizoctonia, Thielaviopsis, Fusarium, and Pratylenchus spp. Y (3-4) Y N N wide host range3,4,5
White mold Sclerotinia sclerotiorum Y (5) N Y (local) N wide host range6
Bean, lima
Downy mildew Phytophthora phaseoli Y (2) Y Y N no records located
Pod blight Phytophthora capsici Y (>3) N Y (local, rain) N common purslane, eastern black nightshade, horsenettle, velvetleaf
Root-knot nematodes Meloidogyne hapla, M. incognita Y (long); small grains N NA N wide host range9
White mold Sclerotinia sclerotiorum Y (5) N Y (local) N wide host range6
Beet      
Cercospora leaf spot Cercospora beticola Y (3) Y Y (local) N several10
Common scab Streptomyces spp. Y (3-4) N N N no records located
Phoma leaf spot Phoma betae Y (3) Y Y (local, rain) N no records located
Pocket rot Rhizoctonia solani Y Y N N wide host range5
Seed rot, damping-off, root rot Pythium ultimum, Rhizoctonia solani Y (3-4) Y N N wide host range4,5
Sugar beet cyst nematode Heterodera schachtii Y (4-5) N NA N field pennycress, tumble pigweed, common lambsquarters, hairy galinsoga
Cabbage, broccoli, cauliflower, and Brussels sprouts
Alternaria leaf spot Alternaria spp. Y (3) Y Y (local) N field pepperweed, Virginia pepperweed, field pennycress
Black leg, seed decay Phoma lingam Y (4) Y Y (local) N weeds in the mustard family
Black rot Xanthomonas campestris pv. campestris Y (3) Y NA N mustard, shepherd's purse, some other weeds in the mustard family
Clubroot Plasmodiophora brassicae Y (7) N NA N several11
Downy mildew Peronospora parasitica Y (3) N Y N wild mustard, yellow rocket, hedge mustard, shepherd's purse, marsh yellowcress, field pennycress suspected; actual hosts might be affected by strain specificity
Fusarium yellows Fusarium oxysporum Y (7) N N N wide host range3
Head rot of broccoli Pseudomonas spp. Y (2) N NA N wide host range
Root-knot nematodes Meloidogyne hapla, M. incognita Y (long); small grains N NA N wide host range9
Root rot Pythium ultimum, Rhizoctonia solani Y (3) Y N N wide host range4,5
White mold Sclerotinia sclerotiorum Y (5) N Y (local) N wide host range6
Wirestem Rhizoctonia solani Y (4-5) Y N N wide host range5
Carrot      
Alternaria leaf blight Alternaria dauci Y (2-3) Y Y (local) N no records located
Aster yellows Aster yellows phytoplasma NA N NA Y (leafhopper) wide host range12
Bacterial leaf blight Xanthomonas campestris pv. carotae Y (2-3) Y NA N mustard, shepherd's purse, some other weeds in the mustard family
Cavity spot Pythium spp. Y (3-4) Y N N several weed hosts4
Cercospora leaf spot Cercospora carotae Y (2-3) Y Y (local) N no records located
Common scab Streptomyces spp. Y (3-4) N N N no records located
Crater rot, foliar blight Rhizoctonia solani Y (4-5) Y N N wide host range5
Damping-off, seed decay Pythium spp., Rhizoctonia spp. N N N N wide host range4,5
Root-knot nematodes Meloidogyne hapla, M. incognita, others Y (long); small grains N NA N wide host range9
White mold, cottony rot Sclerotinia sclerotiorum Y (5) N Y (local) N wide host range6
Celery      
Aster yellows Aster yellows phytoplasma NA N NA Y (leafhopper) wide host range12
Bacterial leaf spot Pseudomonas syringae pv. apii Y (2-3) Y NA N wide host range
Early blight, cercospora leaf spot Cercospora apii Y Y Y (local) N no records located
Late blight, septoria leaf spot Septoria apiicola Y (2) Y Y (local) N no records located
Corn, sweet      
Anthracnose Colletotrichum graminicola Y N Y (local, rain) N several grasses13
Barley yellow dwarf luteovirus (BYDV-PAV) Barley yellow dwarf luteovirus (BYDV- PAV) NA NA Y (aphid) witchgrass, Italian ryegrass, annual bluegrass
Common rust Puccinia sorghi NA N Y N yellow woodsorrel
Common smut Ustilago maydis Y Y Y (local) Y (leafhopper) no records located
Maize dwarf mosaic virus (MDMV) Maize dwarf mosaic virus (MDMV) NA N NA Y (aphid) witchgrass, johnsongrass, barnyardgrass
Northern corn leaf blight Exserohilum turcicum Y (1, 2 w/ no till) N Y (local) N green foxtail, wild-proso millet
Seed rots Fusarium spp., Diplodia spp., etc N N N Y wide host range3
Stewart's wilt Erwinia stewartii NA Y NA Y (flea beetle) no records located
Cucurbits (cucumber, melon, pumpkin, squash, watermelon)
Alternaria leaf blight Alternaria cucumerina Y (2+) Y Y (local) N Virginia copperleaf is a host for Alternaria spp.
Angular leaf spot Pseudomonas syringae Y (2+) Y NA N wide host range
Anthracnose Colletotrichum orbiculare Y (2) Y Y (local, rain) Y no records located
Bacterial fruit blotch Xanthomonas campestris Y (2-3) Y NA N mustard, shepherd's purse, some other weeds in the mustard family
Bacterial leaf spot Acidovorax avenae subsp. Citruli Y ( 3) Y NA Y? (bee) no records located
Bacterial wilt Erwinia tracheiphila NA N NA Y (cucumber beetle) no records located
Belly rot Rhizoctonia solani Y (long) N N N wide host range5
Black rot, gummy stem blight Didymella bryoniae Y (2) Y Y (local) N no records located
Choanephora blossom blight or fruit rot Choanephora cucurbitarum Y (2) N Y (local) N redroot pigweed
Cottony leak Pythium spp. N N N N several weed hosts4
Cucumber mosaic virus (CMV) Cucumber mosaic virus (CMV) NA N NA Y (aphid) wide host range8
Damping-off, root rot Pythium spp., Phytophthora spp. N N N N common purslane, horsenettle, velvetleaf, eastern black nightshade (P. capsici and P. infestans)4
Downy mildew Pseudoperonospora cubensis NA N Y N no records located
Fusarium crown and root rot Fusarium solani f. sp. Cucurbitae Y (5) Y N N no records located
Fusarium wilt (cucumber) Fusarium oxysporum f. sp. Cucumerinum Y (5-7) Y N N no records located
Fusarium wilt (melon) Fusarium oxysporum f. sp. Melonis Y (5-7) Y N N no records located
Root-knot nematodes Meloidogyne hapla, M. incognita Y (long); small grains N NA N wide host range9
Scab Cladosporium cucumerinum Y (2+) Y Y (local) N common sunflower
Septoria leaf spot Septoria cucurbitacearum Y (2+) N Y (local) N no records located
Southern blight Sclerotium rolfsii Y (long); corn, small grains, grass N N N no records located
Ulocladium leaf spot Ulocladium cucurbitae Y (2) N Y (local) N no records located
Verticillium wilt Verticillium dahliae Y (5) Y N N velvetleaf, common sunflower, field pennycress
Watermelon mosaic virus (WMV) Watermelon mosaic virus (WMV) NA N NA Y (aphid) common lambsquarters, burcucumber, jimsonweed, eastern black nightshade, shepherd's purse
White mold Sclerotinia sclerotiorum Y (5) N Y (local) N wide host range6
Zucchini yellow mosaic virus (ZYMV) Zucchini yellow mosaic virus (ZYMV) NA N NA Y (aphid) no records located
Eggplant      
Anthracnose Colletotrichum coccodes Y Y Y (local, rain) N eastern black nightshade, velvetleaf
Alternaria early blight Alternaria solani, A. alternata Y (2-3)   Y (local) N jimsonweed, redroot pigweed, eastern black nightshade (A. solani)
Phytophthora crown or collar rot Phytophthora capsici Y (>3) N Y (local, rain) N field pepperweed, Virginia pepperweed, field pennycress
Phomopsis Phomopsis vexans Y (2-3) N Y (local) N no records located
Root-knot nematodes Meloidogyne hapla, M. incognita Y (long); small grains N NA N wide host range9
Verticillium wilt Verticillium alboatrum, V. dahliae Y (4-5) Y N N wide host range14
Lettuce      
Anthracnose Microdochium panattonianum Y (1) Y Y (local, rain) N prickly lettuce
Aster yellows Aster yellows phytoplasma NA N NA Y (leafhopper) wide host range12
Botrytis gray mold-post harvest Botrytis cinerea Y N Y N common sunflower
Bottom rot Rhizoctonia solani Y (3) N N N wide host range5
Broadbean wilt virus (BBWV) Broadbean wilt virus (BBWV) NA N NA Y (aphid) no records located
Cucumber mosaic virus (CMV) Cucumber mosaic virus (CMV) NA N NA Y (aphid) wide host range8
Damping-off Pythium spp. N Y N N several weed hosts4
Downy mildew Bremia lactucae Y (2-3) N Y N perennial sowthistle, annual sowthistle, prickly lettuce
Drop Sclerotinia sclerotiorum, S. minor Y (3) N Y (local) N wide host range6
Lettuce mosaic virus (LMV) Lettuce mosaic virus (LMV) NA Y NA Y common groundsel, common lambsquarters, annual sowthistle
Root-knot nematodes Meloidogyne hapla, M. incognita Y (long); small grains N NA N wide host range9
Onion      
Bacterial canker, sour skin Burkholderia cepacia N N NA N no records located
Bacterial soft rot Erwinia carotovora subs. Carotovora N N NA N no records located
Botrytis leaf blight Botrytis squamosa Y (3-4) N Y N no records located
Botrytis net rot Botrytis allii Y (2-3) Y Y N no records located
Damping-off Pythium spp., Fusarium spp. Y (Fusarium; small grains) Y (Fusarium) N N wide host range3,4
Downy mildew Peronospora destructor Y (3-4) Y Y N no records located
Fusarium basal rot Fusarium oxysporum f. sp. Cepae Y (4) N N N no records located
Lesion nematodes Pratylenchus spp. Y (long) Y NA N wide host range
Onion yellow dwarf virus (OYDV) Onion yellow dwarf virus (OYDV) Y Y NA Y (aphid) no records located
Pink rot Phoma terrestris Y (3-6) N Y (local) N barnyardgrass, green foxtail, shattercane, witchgrass, field pepperweed, horsenettle
Purple blotch Alternaria porri Y (long) Y Y (local) N Virginia copperleaf is a host for Alternaria spp.
Root-knot nematodes Meloidogyne hapla, M. incognita Y (long); small grains Y NA N wide host range9
Slippery skin Pseudomonas gladioli pv. Allicola Y N NA N wide host range
Smut Urocystis colchici Y Y Y (local) N no records located
Stalk rot Stemphylium botryosum Y (long) Y Y (local) N green foxtail
Stemphylium leaf blight Stemphylium vesicarium Y (long) Y Y (local) N no records located
White rot Sclerotinia cepivorum N N N N no records located
Parsnip      
Aster yellows Aster yellows phytoplasma NA N NA Y (leafhopper) wide host range12
Bacterial blight Pseudomonas marginalis, P. viridiflava Y N NA N wide host range
Pea      
Ascochyta leaf spot Ascochyta pisi Y (3) Y Y (local) N no records located
Bacterial blight Pseudomonas syringae pv. pisi NA Y NA N wide host range
Fusarium wilt Fusarium oxysporum f. sp. pisi Y (long) N N N no records located
Seed decay and root rot Pythium ultimum Y (3-4) Y N N wild-proso millet, shattercane, barnyardgrass, quackgrass
White mold Sclerotinia sclerotiorum Y (5) N Y (local) N wide host range6
Pepper      
Anthracnose fruit rot Colletotrichum gloeosporioides Y (2) Y Y (local, rain) N velvetleaf
Bacterial leaf spot Xanthomonas campestris pv. vesicatoria Y Y NA N mustard, shepherd's purse, some other weeds in the mustard family
Bacterial soft rot Erwinia carotovora N N NA Y no records located
Cucumber mosaic virus (CMV) Cucumber mosaic virus (CMV) NA N NA Y (aphid) wide host range8
Damping-off Phytophthora spp., Pythium spp., Rhizoctonia solani N N N N common purslane, horsenettle, velvetleaf (P. capsici); eastern black nightshade (P. capsici and P. infestans)4,5
Phytophthora blight Phytophthora capsici Y (>3) Y Y (local, rain) N field pepperweed, Virginia pepperweed, field pennycress
Root-knot nematodes Meloidogyne hapla, M. incognita Y (long); small grains N NA Y wide host range9
Southern blight Sclerotium rolfsii Y (long) N N N no records located
Tomato spotted wilt virus (TSWV) Tomato spotted wilt virus (TSWV) NA N NA Y (thrips) wide host range15
Verticillium wilt Verticillium alboatrum, V. dahliae Y (long) N N N wide host range14
Potato      
Bacterial ring rot Clavibacter michiganensis subsp. sepedonicum NA (regulated; 0 tolerance) Y (seed tubers) NA N no records located
Bacterial soft rot Erwinia spp. N N NA N no records located
Black dot root rot Colletotrichum coccodes Y (2) Y (seed tubers) N N eastern black nightshade, velvetleaf
Botrytis vine rot Botrytis cinerea N N Y N common sunflower
Canker and black scurf Rhizoctonia solani Y (3-4) Y (seed tubers) N N wide host range5
Common scab Streptomyces spp. Y (3-4) N N N no records located
Early blight Alternaria solani, A. tomatophila Y (2) N Y (local) N redroot pigweed, eastern black nightshade, jimsonweed (A. solani), Virginia copperleaf (A. sp.)
Fusarium dry rot Fusarium solani, F. sambucinum Y (long) Y (seed tubers) N N green foxtail (F. solani)
Fusarium wilt Fusarium spp. Y (long) Y (seed tubers) N N wide host range3
Golden nematode, Potato cyst nematode (quarantined, NY only) Globodera rostochiensis Y (5-9) Y (seed tubers) NA N no records located
Late blight Phytophthora infestans N Y (seed tubers) Y N eastern black nightshade
Leak Pythium spp. N (>4 if severe) N N N several weed hosts4
Lesion nematodes Pratylenchus spp. Y (long) Y NA N wide host range
Pink rot Phytophthora erythroseptica N (>4 if severe) Y (seed tubers) N N no records located
Powdery scab Spongospora subterranea Y (3-10) Y (seed tubers) N N no records located
Root-knot nematodes Meloidogyne hapla, M. incognita Y (long); small grains N NA N wide host range9
Silver scurf Helminthosporium solani Y (>3?) Y (seed tubers) N N no records located
Verticillium wilt Verticillium alboatrum, V. dahliae Y (long) N N N wide host range14
White mold Sclerotinia sclerotiorum Y (5) N Y (local) N wide host range6
Spinach      
Anthracnose Colletotrichum spinaciae Y (3+) Y Y (local, rain) N no records located
Cucumber mosaic virus (CMV) Cucumber mosaic virus (CMV) NA N NA Y (aphid) wide host range8
Damping-off and seed rot Pythium spp. N N N N several weed hosts4
Downy mildew, blue mold Peronospora effusa Y (2) Y Y N winter spinach, common lambsquarters
White rust Albugo occidentalis Y (3) N Y (local) N no records located
Sweet Potato      
Black rot Ceratocystis fimbriata Y (3-4) Y (seed roots) N N no records located
Fusarium wilt Fusarium oxysporum f. sp. Batatas Y Y (seed roots) N N no records located
Pox, soil rot Streptomyces ipomoea Y (5) Y (seed roots) N N no records located
Root-knot nematodes Meloidogyne hapla, M. incognita Y (long); small grains Y (seed roots) NA N wide host range9
Sclerotial blight, southern blight, circular spot Sclerotium rolfsii Y (3-4) Y (seed roots) N N no records located
Scurf Monilochaetes infuscans Y (2-4) Y (seed roots) N N no records located
Soft rot, rhizopus soft rot Rhizopus stolonifer N N N N no records located
Surface rot, fusarium surface rot Fusarium oxysporum N N N N wide host range3
Sweet potato feathery mottle virus (SPFMV) Sweet potato feathery mottle virus (SPFMV) NA Y (seed roots) NA Y (aphid) no records located
Tomato      
Anthracnose Colletotrichum coccodes Y (3+) Y Y (local, rain) N eastern black nightshade, velvetleaf
Bacterial canker Clavibacter michiganensis subsp. michiganensis Y Y NA N no records located
Bacterial soft rot Erwinia carotovora subsp. Carotovora N N NA N no records located
Bacterial speck Pseudomonas syringae pv. tomato Y (2) Y NA N no records located
Bacterial spot Xanthomonas campestris pv. vesicatoria Y (1-3) Y NA N mustard, shepherd's purse, some other weeds in the mustard family
Botrytis gray mold Botrytis cineria N N Y N common sunflower
Buckeye fruit rot Phytophthora parasitica, P. capsici Y (3+) N Y (local, rain) N common purslane, horsenettle, velvetleaf (P. capsici)
Cucumber mosaic virus (CMV) Cucumber mosaic virus (CMV) NA N NA Y (aphid) wide host range8
Damping-off Pythium spp., Rhizoctonia spp. N N N N wide host range4,5
Double virus streak Tomato mosaic virus (TMV) and potato virus X (PVX) NA Y NA Y (aphid) no records located
Early blight Alternaria tomatophila, A. solani Y (long) Y Y (local) N redroot pigweed, eastern black nightshade, jimsonweed (A. solani), Virginia copperleaf (A. sp.)
Fusarium Fusarium oxysporum f. sp. Lycopersici Y (5-7) Y N N no records located
Late blight Phytophthora infestans N Y Y N eastern black nightshade
Leaf mold Fulvia fulva Y (3+) Y Y N no records located
Phytophthora root rot Phytophthora parasitica, P. capsici Y (3+) N N N common purslane, horsenettle, velvetleaf (P. capsici)
Septoria leaf spot Septoria lycopersici Y (3) Y Y (local) N horsenettle, jimsonweed
Southern blight Sclerotium rolfsii Y (long); corn, cereal, grass N N N no records located
Tomato mosaic virus (TMV) Tomato mosaic virus (TMV) NA N NA Y (aphid) no records located
Tomato spotted wilt virus (TSWV) Tomato spotted wilt virus (TSWV) NA N NA Y (thrips) wide host range15
Verticillium wilt Verticillium alboatrum, V. dahliae Y N N N wide host range14
White mold, timber rot Sclerotinia sclerotiorum N N Y (local) N wide host range6
Turnip, rutabaga and radish
Alternaria leaf spot, brown spot Alternaria spp. Y (2+) Y Y (local) N field pepperweed, Virginia pepperweed, field pennycress
Black rot Xanthomonas campestris pv. campestris Y (3) Y NA N mustard, shepherd's purse, some other weeds in the mustard family
Blackleg Phoma lingam Y (4) Y Y (local, rain) N wild radish
Clubroot Plasmodiophora brassicae Y (7) N NA N wide host range11
Common scab Streptomyces spp. Y (3-4) N N N no records located
Damping-off Pythium spp., Rhizoctonia spp., others N N N N wide host range4,5
Downy mildew Peronospora parasitica Y (3) N Y N wild mustard, yellow rocket, hedge mustard, shepherd's purse, marsh yellowcress, field pennycress
Wirestem Rhizoctonia solani Y (4-5) Y N N wide host range5
FIELD CROPS
Alfalfa
Anthracnose Colletotrichum trifolii Y (2-3) Y Y (local, rain) N no records located
Aphanomyces root rot Aphanomyces euteiches Y (2-3) N N N legumes
Bacterial wilt Clavibacter michiganensis subsp. insidiosus N Y NA N no records located
Brown root rot Phoma sclerotioides Y (3); non- legumes Y N N wide host range
Crown and root rot complex Fusarium spp., Phoma medicaginis, Pythium spp., Rhizoctonia solani Y (long) Y N N wide host range3,4,5
Fusarium wilt Fusarium oxysporum f. sp. Medicaginis Y (long) Y N N no records located
Lepto leaf spot Leptosphaerulina trifolii N N Y (local) N medics, soybean
Lesion nematodes Pratylenchus spp. N N NA N wide host range
Phytophthora root rot Phytophthora medicaginis, P. megasperma f. sp. medicaginis Y (very long) N N N no records located
Sclerotinia crown and stem blight Sclerotinia trifoliorum, S. sclerotiorum Y (3-4) Y Y (local) N wide host range6
Spring black stem and leaf spot Phoma medicaginis Y (2-3) Y Y (local, rain) N legumes
Summer black stem and leaf spot Cercospora medicaginis Y (2-3) Y Y (local, rain) N legumes
Verticillium wilt Verticillium alboatrum Y (3) Y N Y (several) wide host range14
Corn
Anthracnose leaf blight and stalk rot Colletotrichum graminicola Y (2) N Y (local, rain) N several grasses13
Barley yellow dwarf virus Barley yellow dwarf luteovirus (BYDV- PAV) NA N NA Y (aphid) witchgrass, Italian ryegrass, annual bluegrass
Common rust Puccinia sorghi N N Y N yellow woodsorrel
Common smut Ustilago maydis Y (long) Y Y (local) Y (leafhopper) no records located
Diplodia ear rot, stalk rot, seed rot and seedling blight Stenocarpella maydis (Diplodia maydis) Y (2-3); worst in no-till continuous corn N Y N no records located
Diplodia leaf spot, Diplodia leaf streak Stenocarpella macrospora (Diplodia macrospora) Y (2-3) N Y N no records located
Eyespot Aureobasidium zeae Y; worst in no-till continuous corn N Y (local, rain) N no records located
Fusarium stalk and ear rot Fusarium moniliforme Y; worst in no-till continuous corn Y Y (local) Y (European corn borer) grasses
Gibberella stalk and ear rot16 Fusarium spp. Y (2-3); worst in no-till continuous corn Y Y (local) N wide host range3
Gray leaf spot, Cercospora leaf spot Cercospora sorghi Y (1-2); wirst in no-till continuous corn N Y (local) N a few grasses
Leaf blight Erwinia stewartii N Y NA Y (corn flea beetle) a few grasses
Lesion nematodes Pratylenchus spp. N N NA N wide host range
Maize dwarf mosaic virus (MDMV) Maize dwarf mosaic virus (MDMV) N N NA Y (aphid) witchgrass, johnsongrass, barnyardgrass, goosegrass
Northern corn leaf blight Exserohilum turcicum Y (2-3) N Y N johnsongrass, green foxtail, wild-proso millet
Seed rots Fusarium spp., Diplodia spp., etc N N N Y wide host range3
Soybean
Asian soybean rust Pakospora pachyrhizi NA N Y N kudzu, clover, lupin
Brown spot Septoria glycines Y Y Y N no records located
Brown stem rot Phialophora gregata (Cephalosporium gregatum) Y (2-3) N N N unknown; likely
Damping-off, stem rot Rhizoctonia spp., Fusarium spp., Phytophthora sojae, Pythium spp. Y (long) N N N wide host range3,4,5
Diaporthe stem canker Diaporthe phaseolorum (Phomopsis phaseoli) Y Y Y (local, rain) N no records located
Green stem/soybean viruses Bean pod mottle virus NA Y (low levels) NA Y (bean leaf beetle) no records located
Phomoposis seed rot Phomopsis spp. Y Y Y (local, rain) N velvetleaf
Phytophthora root rot Phytophthora sojae Y (long) N N N unknown; likely
Sclerotinia white mold, sclerotinia stem rot Sclerotinia sclerotiorum Y (long) Y Y (local) N wide host range6
Soybean cyst nematode Heterodera glycines Y (3+) Y (in soil with seed) NA N many
Sudden death syndrome Fusarium solani f. sp. Glycines Y (3) N N N no records located
Wheat
Barley yellow dwarf luteovirus (BYDV-PAV) Barley yellow dwarf luteovirus (BYDV- PAV) NA N NA Y (aphid) witchgrass, Italian ryegrass, annual bluegrass etc. (about 105 grass species)
Cephalosporium stripe Hymenula cerealis (Cephalosporium gramineum) Y (2-3) N N N perennial grasses
Common bunt, stinking smut Tilletia tritici NA Y NA N no records located
Common root rot Bipolaris sorokiniana (Cochliobolus sativus) Y (3-6); avoid oat Y Y N grasses
Eyespot foot rot Pseudocercosporella herpotrichoides Y (2+) N Y (local, rain) N likely grass weeds (esp. quackgrass)
Foot rot Fusarium spp. Y (2-3) Y Y (local, rain) N wide host range3
Fusarium scab, head blight16 Fusarium spp. Y (2-3) NA Y (local, rain) N wide host range3
Leaf rust, brown rust Puccinia triticina Y N Y N no records located
Lesion nematodes Pratylenchus spp. Y (2-3) N NA NA wide host range
Loose smut Ustilago tritici NA Y Y (local) N no records located
Powdery mildew Blumeria gramini (Erysiphe graminis f. sp. tritici) Y (1-2) N Y N annual bluegrass
Septoria leaf  blotch Septoria tritici (Mycosphaerella graminicola) Y (1-2) N Y (local, rain) N a few grasses
Stagonospora leaf  and glume blotch Stagonospora nodorum Y (1-2) Y Y (local, rain) N annual bluegrass
Take-all Gaeumannomyces graminis var. tritici Y (2-3); avoid barley N NA N annual bluegrass, quackgrass
Tan spot Pyrenophora triticirepentis Y (2-3) Y Y N a few grasses
Wheat spindle streak mosaic Wheat spindle streak mosaic bymovirus (WSSM) Y (3 or more) N NA N (soilborne protozoan) unknown; likely
Notes

Y indicates yes and N indicates no. For example, in the column labeled “Seed Borne” Y indicates that the pathogen is seed borne and N indicates it is not seed borne.

1 Y= Yes, the disease can be managed by rotation. The number in parentheses is the minimum rotation return time needed for successful management of the disease (see sidebars 5.4 and 5.5). Long means more than just a few years. N= No, the disease cannot be managed through rotation because the pathogen survives too well in the soil or wind disperses the spores too widely. NA= not applicable as the pathogen does not survive in the soil.

2 Y= Spores are dispersed by wind, commonly for several miles. Local= Spores are wind dispersed for short distances, rarely moving farther than adjacent fields. Rain= Spores are dispersed by splashing water and can be moved out of a field by wind during a rainstorm. N= Spores are not dispersed by wind.  NA= Not applicable, as pathogen does not produce spores.

3 Many common weeds host Fusarium species, including barnyardgrass, witchgrass, green foxtail, shattercane, annual bluegrass, wild- proso millet, corn cockle, common sunflower, perennial sowthistle, redroot pigweed, common purslane, and ivyleaf morningglory.

4 Several common weeds host Pythium species, including wild-proso millet, shattercane, barnyardgrass, quackgrass (P. ultimum) and yellow foxtail (P. graminicola).

5 Many common weeds host Rhizoctonia solani, including green foxtail, perennial sowthistle, tumble pigweed, redroot pigweed, prostrate pigweed, common ragweed, barnyardgrass, large crabgrass, goosegrass, kochia, common lambsquarters, eastern black nightshade, common purslane, prickly lettuce, annual bluegrass, wild mustard, shepherd’s purse, Italian ryegrass, field bindweed, mouseear chickweed, field horsetail, Venice mallow, black medic, common milkweed, corn chamomile, wild buckwheat, and witchgrass.

6 Many common weeds host Sclerotinia sclerotiorum, including common lambsquarters, prickly lettuce, wild mustard, eastern black nightshade, field pennycress, redroot pigweed, wild radish, common ragweed, shattercane, annual sowthistle, common sunflower, common chickweed, green foxtail, and Canada thistle. S. minor on lettuce is also hosted by yellow nutsedge.

7 Bean yellow mosaic virus has both cultivated and wild host reservoirs. It can infect most species of the legume family, including herbaceous plants such as sicklepod and other Cassia species, chickpea, crotalaria, soybean, vetchling, sweet pea, lentil, lupine, alfalfa, medics, sweet clover, common bean, pea, clover, fenugreek, vetch, broad bean, and cowpea. It can also infect woody members of the family (pigeon pea, yellowwood, and black locust) and nonlegume species (lambsquarters, freesia, and gladiolus).

8  Many common weeds host CMV, including common chickweed, corn cockle, hairy galinsoga, common groundsel, horsenettle, jimsonweed, common lambsquarters, prickly lettuce, wild mustard, eastern black nightshade, field pennycress, redroot pigweed, common purslane, wild radish, annual sowthistle, Canada thistle, common milkweed, common ragweed, shepherd’s purse, prostrate pigweed, pitted morningglory, tall morningglory, corn speedwell, hedge bindweed, burcucumber, white campion, and marsh yellowcress.

9 Many common weeds host the nematodes Meloidogyne incognita and M. hapla, including common lambsquarters, black medic, field pepperweed, tumble pigweed, velvetleaf, Canada thistle, shepherd’s purse, field pennycress, wild buckwheat, prickly lettuce, wild mustard, yellow rocket, common groundsel, redroot pigweed, large crabgrass, purslane speedwell, hairy galinsoga, prostrate knotweed, and yellow nutsedge.

10 Several weeds host Cercospora beticola, including redroot pigweed, common lambsquarters, roundleaf mallow, white sweetclover, and wild buckwheat.

11 Several weeds host Plasmodiophora brassicae, including wild mustard, common lambsquarters, field pennycress, Virginia pepperweed, shepherd’s purse, yellow woodsorrel, field pepperweed, and wild radish.

12 Several species of leafhopper transmit aster yellows. It has many weed hosts, including dandelion, plantain, Russian thistle, perennial sowthistle, common purslane, shepherd’s purse, Canada thistle, common ragweed, and wild lettuce. There are also ornamental hosts. More than 300 species are susceptible.

13  Many common grasses host Colletotrichum graminicola, including barnyardgrass, quackgrass, witchgrass, johnsongrass, wild-proso millet, large crabgrass, goosegrass, and Italian ryegrass.

14 Many weeds host Verticillium alboatrum, including eastern black nightshade, common purslane, redroot pigweed, horsenettle, common lambsquarters, common cocklebur, common groundsel, and prickly sida. Hosts of V. dahliae include velvetleaf, common sunflower, and field pennycress.

15 Many common weeds host the tomato spotted wilt virus (TSWV), including annual sowthistle, eastern black nightshade, redroot pigweed, shepherd’s purse, field bindweed, prickly lettuce, prostrate pigweed, common purslane, common chickweed, jimsonweed, and wild buckwheat.

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