Transcript Plant Health Management for Backyard Strawberries Planting

Plant Health Management
for Backyard Bramble
(Raspberry and Blackberry)
Plantings
Prepared by
Mike Ellis
Professor and Extension Specialist
and
Omer Erincik
Graduate Research Assistant
Department of Plant Pathology
The Ohio State University
OARDC/OSUE
Wooster, OH, 44691
Common Diseases on Fruit
Gray mold (Botrytis fruit rot)
Symptoms:
One to several blossoms
in a cluster may show
blasting (browning and
drying).
Berries eventually
become covered by a
grayish, dusty, or powdery
growth of the fungus.
Gray mold
Disease Development:
Caused by the fungus Botrytis cinerea
Most infections occur during bloom; however,
symptoms are usually not observed until
harvest.
Temperatures between 70 and 80 °F and free
moisture (water) on the foliage from rain,
dew, fog, or irrigation are ideal conditions for
disease development.
The disease is generally most severe in the
interior areas of the plant canopy where
humidity is higher and air movement is poor.
Management of gray mold
 Free water (wet conditions) is required for
most fungal pathogens to infect fruit. Any
practice that promotes faster drying of fruit
and foliage is beneficial for disease control.
 Site selection
Select a site with good air movement and
sun exposure (promote faster drying).
 Canopy management
Prune to keep row width between 1 or 2
feet in order to encourage air movement
and faster drying.
Control timing and amount of nitrogen
fertilizer to prevent excessive growth.
Management of fruit rot diseases
 Irrigation
If you use overhead irrigation irrigate early
in the day, so that plants can dry faster.
 Handling
Harvest mature fruit promptly to avoid
letting berries become overripe
 Pick fruit carefully, avoid bruising
Process and or refrigerate fruit
immediately after harvest
Common cane diseases on
brambles
Anthracnose
Cane blight
Spur blight
Symptoms of cane diseases
Anthracnose
 Small purple spots develop on young canes.
Eventually, they become grayish and sunken
in the centers surrounded by a reddish margin.
Cane blight
 Brownish-purple to grayish areas, up to
several inches long usually develop around
pruning or other wounds. Branches suddenly
wilt and die above the blighted area.
Spur blight
 Reddish-brown or purplish-brown areas up to
several inches long develop at the nodes on
the young canes. Eventually, the bark may
split lengthwise in the diseased areas.
Cane diseases on brambles
Disease Development:
Causal fungi (pathogens):
Anthracnose……...Elsinoe veneta
Cane blight……….Leptosphaeria coniothyrium
Spur blight……….Didymella applanata
These three fungal pathogens survive over
winter in spots or other infected areas on
canes.
Spores of these pathogens spread to new
canes during spring in splashing water from
rain or overhead irrigation to cause new
infections.
Management of brambles cane
diseases
Use disease free planting stock
Proper site selection
Choose a site with good air circulation and sun
exposure (promotes faster drying).
Pruning (sanitation)
Prune out all canes showing disease symptoms to
reduce pathogen population
Remove infected canes from the planting
Canopy Management:
Avoid over fertilization, especially with nitrogen
Prune to keep row width between 1 to 2 feet to
encourage rapid drying.
Common Diseases Attacking
Roots
Verticillium wilt
Phytophthora root rot
Verticillium wilt
Symptoms:
Starting at the base of the cane
and processing upward, leaves
wilt, turn yellow, and drop.
Black raspberry and blackberry
canes may exhibit a blue color or
purple streaking from the soil line
extending up infected canes to
varying heights.
Verticillium wilt
Disease Development:
 Caused by the soil-borne fungus,
Verticillium albo-atrum
 The fungus can survive in soil for many years.
 The fungus infects roots and plugs waterconducting tissues (xylem). This prevents the
movement of water from the roots to the rest of the
plant; thus, the plant eventually wilts, and dies.
 Disease is favored by wet and poorly drained soils.
Phytophthora root rot
Symptoms:
Healthy canes may suddenly decline
and collapse.
Leaves may initially take on a yellow,
red, or orange color or may begin
scorching along the edges.
Affected canes eventually wilt and die.
On the below-ground portion of the
crown or large roots, a distinct line
can generally be seen between healthy
and infected tissues after scraping
away the outer bark. Infected tissues
are brown to brownish-red.
Phytophthora root rot
Disease development:
caused by Phytophthora spp.
favored by high soil moisture (saturated soil)
and cool temperatures.
infection can occur throughout the growing
season if soil moisture conditions are
favorable.
most destructive in heavy clay soils that are
saturated with water during cool weather.
Management of root diseases
Use healthy planting stock
Proper site selection
Plant in well-drained soil
Select a site that does not have a previous
history of problems with any of the root
diseases.
Sanitation
Dig up diseased plants, including roots,
and remove them from the planting.
Management of root diseases
Rotation
Do not replant brambles where disease
has been a problem for at least 2 years.
Improve soil drainage
Any practice that improves soil drainage
is beneficial to control.
Plant on raised beds
Tile planting areas.
Management of root diseases
 Use resistant varieties for Phytophthora root rot
Phytophthora root rot is most destructive on red
raspberries. Black raspberries are not immune but
appear to be much more resistant than red raspberries.
The disease is rare on blackberries. Although no red
raspberry varieties are completely resistant, varieties
vary greatly in their susceptibility. Choose red raspberry
varieties with higher levels of resistance.
Diseases caused by rust fungi
Orange rust
Late leaf rust
Orange rust
Symptoms:
 The lower surface of infected leaves
become covered with blister-like
pustules. Eventually, the pustules
turn into bright orange, powdery
masses of spores.
 Plants are systemically infected
(fungus grows throughout the plant
and the plant is infected for life). In
years following infection, infected
canes will be bushy and spindly as
they emerge in the spring.
 New leaves on infected canes are
stunted or misshapen and pale-green
to yellowish.
Orange rust
Disease development:
 Orange rust only affects black raspberry and
blackberry. Red raspberries are immune.
 In late May to early June, the bright orange
spores of the pathogen spread from infected
leaves to healthy leaves by the wind and perhaps
rain-splash.
 When environmental conditions favorable
(temperatures between 43 and 72 °F and long
period of wetness), the spores (aeciospores)
germinate and penetrate the leaf causing
localized infections.
Orange rust
Disease development:
 About 45 days later the fungus produces another
type of spore (teliospores) in these infected
areas. During late summer or early fall, these
teliospores produce yet another type of spore
(basidiospore). Basidiospores infect buds at the
base of the plant to cause systemic infection.
 The fungus becomes systemic, growing into the
crown at the base of the infected shoots, and into
newly formed roots.
Leaf late rust
Symptoms:
Small chlorotic or yellow
spots form on the upper
leaf surface.
Small pustules filled
with powdery spores are
formed on the underside
of the infected leaves.
These “rust” pustules
also occur on fruit.
Leaf late rust
Disease development
 Pathogen: Pucciniastrum americanum
 Disease only affects red raspberries. Black
raspberries and blackberries are immune.
 The small, numerous, light yellow spots seen on
the undersurfaces of the leaves are the uredinial
pustules that contain the urediniospores of the
fungus.
 These spores are capable of causing new
infections on leaves and fruit throughout the
growing season.
Management of rust diseases
Use healthy planting stock
Site selection
Select a site with good air movement and sun exposure
(promote faster drying).
Canopy control
Prune to keep row width between 1 or 2 feet in order to
encourage air movement and faster drying.
Control timing and amount of nitrogen fertilizer to prevent
excessive growth.
Sanitation
Remove and destroy infected plants including the roots
(important for orange rust).
Destroy nearby wild brambles that serve as a reservoir
for disease.
Management of rust diseases
Disease resistance:
Orange rust
Red raspberries are immune (completely
resistant)
There are no resistant black raspberry
varieties.
Late leaf rust
Black raspberries and blackberries are
immune.
No red raspberries varieties are resistant.
Using Fungicides For Brambles
Disease Control
Fungicides can be important for disease
control in commercial plantings; however,
fungicides are generally not recommended
for use in backyard bramble plantings.
Effective fungicides are usually difficult or
impossible for backyard growers to obtain.
If not used properly, they are generally not
effective.
For backyard growers
that do wish to use
fungicides in the disease
management program,
fungicide recommendations
are available for brambles in
Bulletin 780 “Controlling
Disease and insects In Home
Fruit Planting”.
Emphasis for disease control in
backyard plantings should be
placed on:
Use of the various cultural practices
for disease control mentioned
previously.
Use of disease resistant varieties
when possible.
Selected literature for backyard fruit
production and plant health
management:
 Bulletin 591. “Growing and Using Fruit at Home”
 Bulletin 780. “Controlling Diseases and Insects in
Home Fruit Planting”
 Bulletin 782. “Brambles Production Management
and Marketing”.
 Bulletin 861. “Midwest Small Fruit Pest
Management Handbook”.
These can be obtained through your county extension
agent or the Extension Publications Office, The Ohio State
University, 385 Kottman Hall, 2021 Coffey Road, Columbus,
Ohio, 43210-1044
To get more information about plant
diseases visit the websites below.
http://www.ag.ohiostate.edu/~plantdoc/extension.php
http://www.ohioline.ag.ohio-state.edu