Transcript Bacteria, Virus, Galls

BACTERIAL DISEASE
BACTERIA
• Lack chlorophyll and cannot produce own
food
• Require 400 to 600X magnification
• Flagella to swim
BACTERIA
PATHOGEN
• Pseudomonas, Xanthomonas,
Agrobacterium, and Erwinia
BACTERIA
LIFE CYCLE
• Dormant in plant material or soil
• Reproduce by mother cell dividing in half
– 2 daughter cells
BACTERIA
• Halo around bacterial leaf spot
BACTERIA
INFECTION
• Do not produce spores (there are
exceptions)
• Pathogen appears as ooze
BACTERIA
INFECTION
• Enter plant through natural openings or
wounds
BACTERIA
CONTROL
• Prevent injuries and introduction
• Copper containing fungicides
– Bordeaux mixture (Copper sulfate and lime)
– Kocide
FIRE BLIGHT
HOST: Rose family (pear, apples, quince…)
• Bradford pear
FIRE BLIGHT
SYMPTOMS
• "Scorched" branches
– Shepherd’s crook
FIRE BLIGHT
INFECTION
• Enter through flowers
• "Ooze" at cankers
FIRE BLIGHT
CONTROL
• Resistant cultivars
• Pruning and sanitizing
Fire Blight
Fire Blight
Fire Blight
Fire Blight
Bacterial Leaf Spot
• Ivy
VIRUS
VIRUS
• True obligate parasites
• Outside living cells act like
chemical substances
• Cannot be cultured on
artificial media
• Virions: virus particles,
seen only with a electron
microscope
VIRUS
SYMPTOMS
• Mosaic / mottling
• Loss of vigor
• Distorted growth
VIRUS
INFECTION
• Infected for life
• Commonly transmitted by insects
– Thrips…
VIRUS
VIRUS
INFECTION
• Rarely kill plant in short amount of time
• Predispose plants
VIRUS
CONTROL
• Avoid transmitting by plant parts
• Reduce vectors
• Resistance
Citrus Greening Disease
• Severe damage to citrus industry
Citrus Greening Disease
• Vectored by Asian citrus psyllid
Citrus Greening Disease
• Fruit inedible and juice undrinkable
CAMELLIA YELLOW MOTTLE
SYMPTOMS
• Sporadic leaves and flowers
• Not stable year to year
• Flowers lose color, variegated
CAMELLIA YELLOW MOTTLE
CONTROL
• Avoid contaminated stock
• Remove plant, if undesirable
Canna Virus
• Vein streaking
• Weakened plants
• Lack of flowering
Canna Virus
• Aphids suspected vector
• No resistant varieties
Nonviral Variegation
• Genetic mutation is heritable
• Some cells stop producing chlorophyll
Viral Variegation
Firepower Nandina
• Propagated in South Carolina
• Infected with two viruses
– Cucumber mosaic virus
– Nandina mosaic virus
Hosta Virus
Hosta Virus
NEMATODES
NEMATODES
• Unsegmented roundworms
• Can be found in every form of plant and
animal
• Most are considered beneficial
NEMATODES
SPECIES
• Sting, Root knot, Cyst, and others
NEMATODES
SPECIES
• There are beneficial species attacking
insects
NEMATODES
SYMPTOMS
• Stunting
• Yellowing
• Wilting
• Stubby roots
NEMATODES
SYMPTOMS
• Only Root Knot and Cyst nematodes
cause ID symptoms
• ID by lab
NEMATODES
SYMPTOMS
• Cyst nematodes
NEMATODES
DAMAGE
• Severely damage roots
NEMATODES
DAMAGE
• Foliar nematodes
NEMATODES
CONTROL
• Fumigation
• Biological controls
– Chitin, fungal
• Nematicides
GALLS
GALLS
SYMPTOMS
• Distortions or swellings
• Leaves, flowers, branches, or trunk
GALLS
Insect-causing
• Harbor the eggs and larva
• Larval secretions induce abnormal growth
– Hyperplasia
• Protection and food
GALLS
Bacteria
• Crown gall (Agrobacterium
tumefaciens)
• Gall at root crown (often)
• Can kill young plants
Bacterial Gall on Rosemary
• http://www.missouribotanicalgarden.org/ga
rdens-gardening/your-garden/help-for-thehome-gardener/advice-tipsresources/pests-andproblems/diseases/bacterial-galls.aspx
Bacterial Gall on Rosemary
• http://www.missouribotanicalgarden.org/ga
rdens-gardening/your-garden/help-for-thehome-gardener/advice-tipsresources/pests-andproblems/diseases/bacterial-galls.aspx
Bacterial Gall on Rosemary
• http://www.missouribotanicalgarden.org/ga
rdens-gardening/your-garden/help-for-thehome-gardener/advice-tipsresources/pests-andproblems/diseases/bacterial-galls.aspx
Bacterial Gall on Rosemary
• http://www.missouribotanicalgarden.org/ga
rdens-gardening/your-garden/help-for-thehome-gardener/advice-tipsresources/pests-andproblems/diseases/bacterial-galls.aspx
Bacterial Gall on Rosemary
• http://www.missouribotanicalgarden.org/ga
rdens-gardening/your-garden/help-for-thehome-gardener/advice-tipsresources/pests-andproblems/diseases/bacterial-galls.aspx
Crown gall
• Crown gall (Agrobacterium tumefaciens)
GALLS
Crown gall (Agrobacterium tumefaciens)
GALLS
CONTROL
• Prune out galls
• Purchase healthy stock
Leaf Gall
PATHOGEN: Fungal
HOST: Azalea and Sassanqua
GALLS
SYMPTOMS
• Individual leaves thick and fleshy
• Early spring
GALLS
CONTROL
• Hand pick
• Rarely chemical