Nematode Diseases of Perennials Symptoms & Signs Dr. James A. LaMondia

1. Nematode Diseases of Perennials Symptoms & Signs Dr. James A. LaMondia Plant Pathologist/Nematologist The Connecticut Agricultural Experiment Station, Valley Laboratory Windsor, CT

2. Nematodes Infecting Perennials Meloidogyne hapla - root-knot Aphelenchoides - foliar nematodes Ditylenchus - stem/bulb nematodes Pratylenchus - lesion nematodes

3. Nematode Diagnostics 30% (99 of 333) samples submitted over 5 years were infected with Meloidogyne hapla

4. Perennial Ornamentals > 2500 species in >500 genera. Value over $1 billion in US. Propagation by division, seed, and cuttings.

5. Non-specific Damage Symptoms of poor roots Poor color and vigor Reduce winter hardiness Secondary pathogens/diseases

10. Nematodes Infecting Perennials Meloidogyne hapla - root-knot Aphelenchoides - foliar nematodes Ditylenchus - stem/bulb nematodes Pratylenchus - lesion nematodes

15. Nematodes Infecting Perennials Meloidogyne hapla - root-knot Aphelenchoides - foliar nematodes Ditylenchus - stem/bulb nematodes Pratylenchus - lesion nematodes

18. Nematode Diseases of Tree Fruits

19. Nematode Damage Reduce tree vigor and yield Reduce winter hardiness Transmit viruses (TmRSV) - apple union necrosis - peach stem pitting Replant Diseases

20. Nematodes Infecting Tree Fruits Pratylenchus - lesion nematodes Xiphinema - dagger nematodes Criconemella - ring nematodes Meloidogyne hapla - root-knot

21. Nematode Damage Levels Lesion - 25-150 per 100 cm3 soil Ring - 50-200 per 100 cm3 soil Dagger - 1-100 per 100 cm3 soil (depends on TmRSV)

23. Apple Replant Trees appear stunted, and growth uneven and slow. Associated with lesion nematodes, soil fungi and bacteria, and poor soil conditions.

24. Apple or Fruit Replant Disease

25. Ring Nematode

27. Apple Union Necrosis

28. Apple Union Necrosis Problem only on size-controlling rootstocks such as MM106 and scions such as Red Delicious. Shoot growth reduced, heavy set of small fruit, not always lethal.

29. Tomato RingSpot Virus History

30. Weed Hosts of TmRSV Common chickweed Lambsquarters White-head aster Oxeye daisy Common thistle Dandelion Wild carrot Swine or Pennycress Leafy/prostrate spurge Red or White clover Common polkweed Buckhorn plantain Common mullein Common plantain Sheep sorrel (red) Curly dock Wild strawberry Broadleaf plantain

31. Peach Stem Pitting Affected trees appear girdled, lose vigor and eventually die. Trees often yellow early, and set a large number of small fruit. Pits or grooves occur in rootstock.

32. Cultural Practices • Site preparation • Rotation crops - Brassicas or sorghosudan/sudangrass. • Sod strips - perennial rye or fescue grasses and weed control.

33. Nematicides • Need determined for each field • Fumigant Nematicides 1,3-dichloropropene metam sodium or dazomet • Non-fumigant Nematicides Fenamiphos or oxamyl

34. Strawberry Black Root Rot: Plant and Pathogen Interactions James A. LaMondia The Connecticut Agricultural Experiment Station Valley Laboratory Windsor, CT

39. DISEASE TRIANGLE Host Plant Causal Agent DISEASE Environment

41. Effect of pathogens on root disease and length %BRRStructuralFeeder None10 526 1124 Rf alone 22 491 1440 Rf + Pp 46 411 654

42. Strawberry Root Types Structural roots – 1° & 2 ° well developed cortex. Perennial roots – 2 ° tissues root cortex sloughed off. Feeder roots – 1 ° tissues short-lived, quick cycles.