Australasian Plant Pathology Society

 
Pathogen of the Month
  Submissions for POTM are welcome. Please contact Megan Blake for details.  Email  
    see also Technology of the Month    
       
    Diaporthe toxica   the latest POTM March 2026    
View PDF Pathogen Disease Host Crop Taxon
 

Aceria tosichella		 Aceria tosichella Wheat Curl Mite Wheat, cereals and grasses Grains and Field Crops Arthropods

Alternaria alternata		 Alternaria alternata Alternaria leaf spot Cotton Grains and Field Crops Fungi

Aphanomyces euteiches		 Aphanomyces euteiches Aphanomyces Root Rot Legumes Grains and Field Crops Fungi

Aphelenchoides fragariae		 Aphelenchoides fragariae Bud and Leaf Nematode Many host species Many Hosts Nematodes

Armillaria luteobubalina		 Armillaria luteobubalina Armillaria root rot Australian natives Forestry and Amenity Fungi

Blumeria graminis f. sp. hordei 		Blumeria graminis f. sp. hordei Barley Powdery Mildew Barley Grains and Field Crops Fungi

Botrytis squamosa		 Botrytis squamosa Onion Leaf Blight Allium spp., onion, garlic, and leek. Vegetables Fungi

Calonectria ilicicola		 Calonectria ilicicola Collar Rot Many hosts including papaya Many Hosts Fungi

Candidatus Phytoplasma		 Candidatus Phytoplasma Witches’ broom, big bud, little leaf Many host species Many Hosts Bacteria

Candidatus Liberibacter		 Candidatus Liberibacter Zebra Chip Solanaceae Vegetables Bacteria

Candidatus Liberabacter		 Candidatus Liberabacter Citrus greening Citrus spp. Fruit and Nut Crops Bacteria

Ceratobasidium theobromae		 Ceratobasidium theobromae Vascular Streak Dieback Cocoa Fruit and Nut Crops Fungi

Cercospora zonata		 Cercospora zonata Cercospora leaf spot Vicia species and more Many Hosts Fungi

Cladobotrium spp		 Cladobotryum spp Cobweb Disease Mushrooms Vegetables Fungi

Cladosporium echinulatum		 Cladosporium echinulatum Fairy Ring Spot of Carnation Carnation Ornamentals Fungi

Cochliobolus heterostrophus		 Cochliobolus heterostrophus Southern corn (maydis) leaf blight Maize Fruit and Nut Crops Fungi

Colletotrichum acutatum		 Colletotrichum acutatum Pistachio anthracnose A diverse range of hosts Many Hosts Fungi

Colletotrichum coccodes		 Colletotrichum coccodes Brown Root Rot Tomato and Potato Vegetables Fungi

Colletotrichum gloeosporioides		 Colletotrichum gloeosporioides Anthracnose Many host species Many Hosts Fungi

Colletotrichum graminicola		 Colletotrichum graminicola Maize anthracnose Maize Grains and Field Crops Fungi

Colletotrichum lupini		 Colletotrichum lupini Lupin anthracnose Lupin, Lupinus spp. Grains and Field Crops Fungi

Cryphonectria parasitica		 Cryphonectria parasitica Chestnut blight, chestnut canker Chestnut and oak Fruit and Nut Crops Fungi

Dactylonectria spp		 Dactylonectria spp Black root rot Avacado Fruit and Nut Crops Fungi

Diaporthe toxica		 Diaporthe toxica Lupinosis, Phomopsis stem blight Lupin, Lupinus spp. Grains and Field Crops Fungi

Ditylenchus destructor		 Ditylenchus destructor Potato Rot Nematode Potato plus many other plants Vegetables Nematodes

Ditylenchus dipsaci		 Ditylenchus dipsaci Stem Nematode, Bulb Nematode Many host species Many Hosts Nematodes

Dothistroma septosporum		 Dothistroma septosporum Dothistroma needle blight Pinus and other conifers Forestry and Amenity Fungi

Entyloma ageratinae		 Entyloma ageratinae Mistflower blight Mistflower Ornamentals Fungi

Erwinia amylovora		 Erwinia amylovora Fire Blight Apple, pear, cotoneaster, hawthorn. Fruit and Nut Crops Bacteria

Erysiphe heraclei		 Erysiphe heraclei Powdery Mildew Many members of Apiaceae Many Hosts Fungi

Erysiphe necator		 Erysiphe necator Powdery Mildew Grapevine Fruit and Nut Crops Fungi

Eutiarosporella spp.		 Eutiarosporella spp. White Grain Triticum spp, Hordeum spp Grains and Field Crops Fungi

Fusarium graminareum		 Fusarium graminareum Head blight and crown rot Many small grains Grains and Field Crops Fungi

Fusarium oxysporum f.sp. cubense		 Fusarium oxysporum f.sp. cubense Panama Disease or Fusarium Wilt Bananas Fruit and Nut Crops Fungi

Fusarium oxysporum f.sp. conglutinans		 Fusarium oxysporum f.sp. conglutinans Wilt of Canola Canola and other Brassicas Grains and Field Crops Fungi

Fusarium oxysporum f.sp. vasinfectum		 Fusarium oxysporum f.sp. vasinfectum Wilt of Cotton Cotton Grains and Field Crops Fungi

Fusarium virguliforme		 Fusarium virguliforme Soybean sudden death syndrome Soybean Grains and Field Crops Fungi

Ganoderma boninense		 Ganoderma boninense Basal Stem Rot Many hosts, Eucalyptus and palms Many Hosts Fungi

Giberella circinata		 Giberella circinata Pine Pitch Canker Pinus species Forestry and Amenity Fungi

Globodera rostochiensis		 Globodera rostochiensis Potato Cyst Nematode Potato Vegetables Nematodes

Gnomoniopsis smithogilvyi		 Gnomoniopsis smithogilvyi Chestnut rot Chestnuts Fruit and Nut Crops Fungi

Hardenbergia mosaic virus		 Hardenbergia mosaic virus Hardenbergia mosaic virus Hardenbergia comptoniana Ornamentals Virus

Helicotylenchus spp.		 Helicotylenchus spp Nematodes Banana Fruit and Nut Crops Nematodes

Heterodera carotae		 Heterodera carotae Carrot cyst nematode disease Cultivated and wild carrots Vegetables Nematodes

Hymenochaetesemi stupposa		 Hymenochaetesemi stupposa Incipient rot and white pocket rot Eucalyptus diversicolor (Karri) Forestry and Amenity Fungi

Ibipora lolii		 Ibipora lolii Southern Sting Nematode Turf and a wide range of vegetable crops Ornamentals Nematodes

Ilyonectria macrodidyma		 Ilyonectria macrodidyma Grapevine black foot disease Grapevine, Vitis spp. Fruit and Nut Crops Fungi

Inocutis jamaicensis		 Inocutis jamaicensis Inocutis stem rot, chlorotic leaf roll Eucalyptus spp., Vitis vinifera, Acacia spp Many Hosts Fungi

Ips grandicollis		 Ips grandicollis Five–spined bark beetle/engraver Pinus radiata Forestry and Amenity Arthropods

Kordyana brasiliensis		 Kordyana brasiliensis Tradescantia yellow spot fungus Tradescantia fluminensis Ornamentals Fungi

Lecanicillium fungicola var. fungicola		 Lecanicillium fungicola var. fungicola Dry bubble disease Cultivated mushrooms Vegetables Fungi

Leptosphaeria maculans		 Leptosphaeria maculans Blackleg Canola Grains and Field Crops Fungi

Little cherry virus 2		 Little cherry virus 2 Little cherry virus 2 Prunus avium, P. cerasus Fruit and Nut Crops Virus

Luteoviridae Viruses		 Luteoviridae Viruses Luteoviridae Viruses Pulses Grains and Field Crops Virus

mayetiola destructor		 mayetiola destructor Hessian Fly Wheat Grains and Field Crops Arthropods

Meloidogyne fallax		 Meloidogyne fallax Root knot nematode Crops and more Many Hosts Nematodes

Meloidogyne spp.		 Meloidogyne spp. Nematodes Banana Fruit and Nut Crops Nematodes

Meloidogyne incognita		 Meloidogyne incognita Root-knot nematode Many plants Many Hosts Nematodes

Microdochium panattonianum		 Microdochium panattonianum Anthracnose Lettuce Vegetables Fungi

Monilinia fructicola		 Monilinia fructicola Brown rot of stone fruit Stone fruit Fruit and Nut Crops Fungi

Mycosphaerella cryptica		 Mycosphaerella cryptica Leaf blotch, crinkle leaf Eucalyptus spp. Forestry and Amenity Fungi

Mycosphaerella fori		 Mycosphaerella fori Mycosphaerella Leaf Disease Eucalyptus globulus Forestry and Amenity Fungi

Neofusicoccum luteum		 Neofusicoccum luteum Botryosphaeria dieback Grapevines, Blueberry Fruit and Nut Crops Fungi

Papaya ringspot virus		 Papaya ringspot virus Papaya ringspot virus Papaya Fruit and Nut Crops Virus

Paraphoma vinacea		 Paraphoma vinacea Crown Rot Tanacetum cinerariifolium Ornamentals Fungi

Phellinus noxius		 Phellinus noxius Brown root rot Hoop pine and Avocado Fruit and Nut Crops Fungi

Phoma koolunga		 Phoma koolunga Ascochyta blight (syn: blackspot) Pisum sativum (Peas) Vegetables Fungi

Phyllosticta citricarpa		 Phyllosticta citricarpa Citrus black spot Citrus spp. Fruit and Nut Crops Fungi

Phytophthora capsici		 Phytophthora capsici Chilli blight or Phytophthora blight Many vegetables Vegetables Oomycetes

Phytophthora cinnamomi		 Phytophthora cinnamomi Dieback or root rot Wide range include Aust. natives Forestry and Amenity Oomycetes

Phytophthora palmivora		 Phytophthora palmivora Fruit rots, stem cankers, blights Over 1000 plant species Many Hosts Oomycetes

Phytophthora parvispora		 Phytophthora parvispora Gummosis and root rot; brown fruit rot Citrus Fruit and Nut Crops Oomycetes

Phytophthora ramorum		 Phytophthora ramorum Sudden Oak Death Wide range include Aust. natives Forestry and Amenity Oomycetes

Phytophthora mekongensis		 Phytophthora mekongensis Brown fruit rot, Gumosis Citrus spp. Fruit and Nut Crops Oomycetes

Phytophthora multivora		 Phytophthora multivora Dieback Eucalyptus spp. Forestry and Amenity Oomycetes

Phytophthora inundata		 Phytophthora inundata Collar Rot Many Australian native species Forestry and Amenity Oomycetes

Phytophthora nicotianae		 Phytophthora nicotianae Rots, Blights and Cankers Many species Many Hosts Oomycetes

Banana wilt associated phytoplasmas		 Phytoplasmas Banana wilt Banana Fruit and Nut Crops Bacteria

Plasmodiophora brassicae		 Plasmodiophora brassicae Clubroot Brassicaceae Vegetables Fungi

Plasmopara viticola		 Plasmopara viticola Downy Mildew Grapevines Fruit and Nut Crops Fungi

Pratylenchus brachyurus		 Pratylenchus brachyurus Ill-thrift, Root Lesion Peanut and Pineapple Fruit and Nut Crops Nematodes

Pratylenchus coffeae		 Pratylenchus coffeae Root lesion Musa species Fruit and Nut Crops Nematodes

Pratylenchus goodeyi		 Pratylenchus goodeyi Lesion nematode Musa spp., Bananas Fruit and Nut Crops Nematodes

Pratylenchus penetrans		 Pratylenchus penetrans Root lesion nematode Many hosts Many Hosts Nematodes

Pratylenchus penetrans		 Pratylenchus penetrans Root lesion nematode Potato Vegetables Nematodes

Pratylenchus spp.		 Pratylenchus spp. Nematodes Banana Fruit and Nut Crops Nematodes

Pratylenchus zeae		 Pratylenchus zeae Root lesion nematode Grasses and more Many Hosts Nematodes

Pseudocercospora macadamiae		 Pseudocercospora macadamiae Husk spot Species of Macadamia Fruit and Nut Crops Fungi

Pseudoidium anacardii		 Pseudoidium anacardii Citrus Powdery Mildew Many Hosts Fruit and Nut Crops Fungi

Pseudomonas syringae pv. actinidiae		 Pseudomonas syringae pv. actinidiae Bacterial canker of kiwifruit Actinidia sp. Kiwifruit Fruit and Nut Crops Bacteria

Pseudomonas syringae pv. syringae		 Pseudomonas syringae pv. syringae Bacterial Inflorescence Rot Many hosts, grapevine, beans, avacado Many Hosts Bacteria

Puccinia graminis f.sp. tritici		 Puccinia graminis f.sp. tritici Stem rust of wheat Wheat and some other cereals Grains and Field Crops Fungi

Puccinia hordei		 Puccinia hordei Barley leaf rust Barley Grains and Field Crops Fungi

Puccinia psidii (Austropuccinia Beenken gen. nov. https://doi.org/10.11646/phytotaxa.297.1.5)		 Puccinia psidii (Austropuccinia gen. nov.) Guava Rust, Eucalyptus Rust Myrtaceae Many Hosts Fungi

Puccinia psidii (Austropuccinia Beenken gen. nov. https://doi.org/10.11646/phytotaxa.297.1.5)		 Puccinia psidii (Austropuccinia gen. nov.) Myrtle, Guava, and Eucalyptus Rust Myrtaceous hosts Many Hosts Fungi

Pyrenochaeta lycopersici		 Pyrenochaeta lycopersici Corky root Tomato and other Solonaceae Vegetables Fungi

Pyricularia angulata		 Pyricularia angulata Banana Blast Banana Fruit and Nut Crops Fungi

Pythium sulcatum		 Pythium sulcatum Cavity Spot Apiaceae, carrot Vegetables Oomycetes

Quambalaria coyrecup		 Quambalaria coyrecup Corymbia canker disease Corymbia calophylla, C. ficifolia Forestry and Amenity Fungi

Radopholus spp.		 Radopholus spp. Nematodes Banana Fruit and Nut Crops Nematodes

Radopholus nativus		 Radopholus nativus Burrowing Nematode Wheat and barley and other rotation crops Grains and Field Crops Nematodes

Radopholus similis		 Radopholus similis Burrowing Nematode Citrus, Banana, Black Pepper and more Many Hosts Nematodes

Ralstonia solanacearum		 Ralstonia solanacearum Bacterial Wilt Tomato Vegetables Bacteria

Rhizoctonia solani		 Rhizoctonia solani Onion Stunting Onions Vegetables Fungi

Rhizoctonia carotae		 Rhizoctonia carotae Crater rot of carrot Carrot also celery, swedes, cabbage, beet. Vegetables Fungi

Rotylenchulus reniformis		 Rotylenchulus reniformis Reniform nematode Many hosts Many Hosts Nematodes

Sclerotinia minor		 Sclerotinia minor Lettuce drop / Sclerotinia Lettuce Vegetables Fungi

Sphaceloma perseae		 Sphaceloma perseae Avocado scab Avocados (Persea americana) Fruit and Nut Crops Fungi

Stagonosporopsis cucurbitacearum		 Stagonosporopsis cucurbitacearum Gummy stem blight disease cucurbitaceous vegetable crops Vegetables Fungi

Thielaviopsis basicola		 Thielaviopsis basicola Black root rot Cotton Fruit and Nut Crops Fungi

Tilletia indica		 Tilletia indica Karnal bunt Wheat, durum, triticale Grains and Field Crops Fungi

Tobaco Mosaic Virus		 Tobacco Mosaic Virus Tobaco Mosaic Virus Solanaceae and many other hosts Many Hosts Virus

Tobaco Mosaic Virus		 Tobamovirus fructirugosum Tomato brown rugose fruit virus Tomato, Capsicum and more Vegetables Virus

Tomato spotted wilt tospovirus		 Tomato spotted wilt tospovirus Tomato spotted wilt tospovirus Solanaceae and many other hosts Many Hosts Virus

Trogoderma granarium		 Trogoderma granarium Khapra beetle Cereal grains, flour, malt and noodles Grains and Field Crops Arthropods

Uredo rangelli		 Uredo rangelli Myrtle Rust Myrtaceous species Many Hosts Fungi

Uromycladium tepperianum		 Uromycladium tepperianum Galls and witches’ brooms of wattles Aust. Acacia spp., Paraserianthes spp. Forestry and Amenity Fungi

Verticillium dahliae		 Verticillium dahliae Verticillium wilt Many Hosts Many Hosts Fungi

Wheat streak mosaic virus		 Wheat streak mosaic virus Wheat streak mosaic virus Cereals Grains and Field Crops Virus

Yellow tailflower mild mottle virus		 Yellow tailflower mild mottle virus Yellow tailflower mild mottle virus Yellow tailflower Ornamentals Virus

Xanthomonas axonopodis		 Xanthomonas axonopodis Citrus canker Citrus and other Rutaceae spp. Fruit and Nut Crops Bacteria

Xanthomonas translucens pv. pistaciae		 Xanthomonas translucens pv. pistaciae Pistachio Dieback Pistachio Fruit and Nut Crops Bacteria

Xanthomonas axonopodis pv. punicae		 Xanthomonas axonopodis pv. punicae Bacterial blight Pomegranate Fruit and Nut Crops Bacteria

Xanthomonas fragariae		 Xanthomonas fragariae Angular Leaf Spot Strawberrry Fruit and Nut Crops Bacteria

Xylella fastidiosa		 Xylella fastidiosa Pierce’s Disease, Leaf Scold or Scorch Many Hosts Many Hosts Bacteria

Zucchini yellow mosaic virus		 Zucchini yellow mosaic virus Zucchini yellow mosaic virus Cucurbitaceae Vegetables Virus

Zythiostroma sp.		 Zythiostroma sp. Aerial canker in Banksia Proteaceae spp. Forestry and Amenity Fungi