Download VT VEGETABLE AND BERRY MEETING January 25, 2016 Ann Hazelrigg

VT VEGETABLE AND BERRY MEETING
January 25, 2016
Ann Hazelrigg
Celery anthracnose-new fungus disease-warm/high RH
Michigan since 2010 causing large losses
Curled and twisted foliage like herbicide
injury or aster yellows virus trans by
leafhoppers
Celery anthracnose-rotation, fungicides, plow down
Heart rot can also be caused by calcium imbalance
Potato leafhoppers
• 200 species of plants-potatoes, beans, raspberries
• Arrives on storm fronts in spring
• indicator of climate change-arriving 10 days earlier
than 1950s or one day each 6 years
• Migratory pests/diseases will be more affected by
climate change-late blight, leaf hoppers,
downy mildews, etc.
CABBAGE APHIDS
• Severe problem last summer/fall
• 2% infestation organic/10% conventional
• Gray/white waxy coating-repellant/insecticidepyrethrum,
neem, insecticidal soap, mixed with an adjuvant
worked in Mass.
• Can build up rapidly over course of season
• Migrate north, but winter growing gives
overwintering bridge
• Can damage growing points/head formation
• Release lady bugs-Cornell
• Scout early in high tunnels
Onion leek moth continues to expand range
Addison
Chittenden
Franklin
Grand Isle
Lamoille
Orleans
Orange
Rutland
Second generation most damaging in July/August as it feeds
on emerging leaves and makes its way to bulb/base
Onion leek moth
• Insecticides-hard to time use traps to
determine flights and apply 7-10 days
later..
• Row covers
• Turn under debris in fall
• Rotation-more than 100-200m but can
blow around
Onion downy mildew-cool/moist conditions in Julycan defoliate and decrease bulb size-OW in debris
Basil downy mildew-7/24 Chittenden co.
Some less susceptible-Eleanora (delay by
2 weeks, but not immune
Keep leaves dry, humidity low
Fungicides registered but must spray
early and often
Late blight in potato-7/7
Likely from seed-did not spread much
Tomato late blight not seen until
August. Did not seem too devastating.
WET in JUNE! Phytophthora fruit rot- soil borne
24 hrs saturated soil
Bottom rot/web blight lettuce-wet June, soil borne
fungus splashes up
CUCUMBER SCAB
• Cool and wet conditions, fogs,
etc
• Olive green spores
• Summer squash/winter squash
• Resistant cuke varieties
• Good rotation
Fungicides work but tough with
prolonged wetness
Crucifers-Black rot
Hot water seed treatment
EMBELLESIA BLOTCH
• Harvest disease-largely
cosmetic
• Diffuse charcoal colored
blotches usually restricted to
first few wrappers, can be
unmarketable
• Spores ow in old leaf tissue so
clean up old storage areas
• Keep RH below 70%
FUSARIUM DRY ROT
Soil borne fungus
Enters through basal plate
Likes high RH
Rotation
Cull seed
GARLIC BULB MITES
GARLIC WHITE ROT-very destructive, cool
conditions, sclerotia, long rotation out of alliums
Cladosporium leaf spot
Fungal disease
Likes free moisture
Repeated crops
Spread out plants
SPINACH CROWN MITE
• Roots look fine
• Curling/puckering at growing
point
• Neem spot treat
Bacterial leaf blight carrot
Alternaria leaf blight-more prevalent on
older tissue, cercospora on newer tissue
Some resistance, maintain good N fertility
Black leg potato- E. caratovora/Pectobacterium
• Black lesions on stems begin at the decaying seed piece, collapse
• Seed borne-resides in lenticels until right conditions (under 65 cool/moist)
• New seed borne disease in Maine-Dickeya
• Same thing but on steroids..
• Be aware of seed source
• Disinfest cutting knives
• Avoid planting in wet soils
Greenhouse sanitation
Keep hoses off ground
Clean up weeds
Use clean flats
Promote quick germination
Avoid cool wet soils
Most early season problems are noninfectious-always check NEW growth
Send a sample or picture!
• [email protected]
• [email protected]
• 656.0493
• http://pss.uvm.edu/pd/pdc/