Symptoms- Scales attack leaves, flowers, shoots and canes of most
Ribes species. Infested plants appear
yellowish and unhealthy; many of the infested canes eventually die. Seriously
infested plant stems appear grayish, as if coated with ash. The mature female
scale is about the size of a pinhead and circular in shape, with a
nipple-like prominence in the center. Scale insects may be a problem on
black, red, white, and ornamental currants, and gooseberries.
Management Options
Guideline
Scouting/thresholds
None established.
Resistant cultivars
None known.
Cultural management
None established.
Conventional
and
Organic
products
A dormant crop oil spray (4 gal) in
10 gal water applied before the buds swell and burst in the spring is
recommended.
6.2.2
BURST TO LEAF
6.2.2.1
Powdery Mildew
Symptoms- Powdery mildew overwinters
on currant and gooseberry twigs. Initially, white powdery patches of mycelium
and spores appear on the leaves and shoots in early spring. As time passes,
these patches turn rusty brown. Newly formed fruit also become infected,
showing the same powdery lesions. Infected berries become cracked and may
shatter. Infected leaves may drop prematurely
during hot weather. Heavily infected plants appear stunted and may be killed
by the disease.
Management Options
Guideline
Scouting/thresholds
None established.
Resistant cultivars
Resistance to this disease is highly
variable, depending on the cultivar planted. American cultivars are generally
more resistant than the European varieties.
Cultural management
Prune and trellis plants to improve
air circulation.
Conventional products
Sprays are most necessary during
humid or wet weather in the spring. In plantings where disease historically
occurs, apply the first application before typical time of disease onset.
A.myclobutanil- Rally 40WSP (5.0 oz/A).
Do not apply more than 40 oz per acre per season. OR
B.pyraclostrobin- Cabrio
EG (14 oz/A). Begin applications prior to disease development and continue on
a 7 - 14 day schedule. Use the shorter interval when disease pressure is
high. Note: Do not apply more than four applications of Cabrio per season. Do not apply more than 2 sequential
applications of Cabrio before alternating to
another fungicide with a different mode of action. OR
C.paraffinic oil- JMS Stylet Oil (3 6
qt/100 gal water). Apply when the first signs of powdery mildew are apparent
and repeat as necessary but with care. Excessive applications may delay
ripening or reduce sugar accumulation in the berries. The oil kills powdery
mildew colonies on contact, thus, high water volumes and thorough coverage of
the leaves and developing fruit are essential for good results. Many common
pesticides (including sulfur) are phytotoxic when
applied in combination with or close to oil sprays; check label for specific
restrictions. OR
D.sulfur- MicrothiolDispress (6 15 lb/A) or Millers Lime Sulfur
Solution 29% (1.5 qt/100 gal water). Apply after first signs of the disease appear
and repeat at regular intervals following rates and restrictions given on the
label. Do not apply lime sulfur during bloom, only before and after the bloom
period. Caution: Some gooseberry varieties are sulfur shy and will be
damaged by these sprays, especially during warm weather. If sulfur
sensitivity is unknown, observe your plants closely.
Organic products
(May also be used in conventional production.)
A.paraffinic oil- Organic JMS Stylet
Oil (3 6 qt/100 gal water). Apply when the first signs of powdery mildew
are apparent and repeat as necessary but with care. Excessive applications
may delay ripening or reduce sugar accumulation in the berries. The oil kills
powdery mildew colonies on contact, thus, high water volumes and thorough coverage
of the leaves and developing fruit are essential for good results. Many
common pesticides (including sulfur) are phytotoxic
when applied in combination with or close to oil sprays; check label for
specific restrictions. OR
B.potassium bicarbonate Kailgreen 2.5
3.0 lb/A). Do not mix with highly acidic products or nutrients. OR
C.StreptomyceslydicusWYEC108- Actinovate
AG (3-12 oz/A). Foliar applications: for best results apply with a spreader/sticker
prior to onset of disease. Re-apply at 7-14 day intervals depending on
disease pressure and environmental conditions. OR
D.sulfur- Kumulus DF (6 15 lb/A) orThiolux Jet 80DF (6 15 lb/A
on gooseberry; 5 10 lb/A on currant). Apply after first signs of the
disease appear and repeat at regular intervals following rates and
restrictions given on the label. Do not apply lime sulfur during bloom, only
before and after the bloom period. Caution: Some gooseberry varieties are
sulfur shy and will be damaged by these sprays, especially during warm
weather. If sulfur sensitivity is unknown, observe your plants closely
6.2.2.2
Currant Aphid
Symptoms- The aphid is most common
on red and white currant, and may sometimes be found on gooseberry. The
leaves of infested plants are cupped, galled, distorted, and discolored; the
upper leaf surfaces are most seriously affected. Honeydew excreted by the
aphids covers the foliage and fruit with a sticky coating.
Management Options
Guideline
Scouting/thresholds
None established.
Resistant cultivars
None known.
Cultural management
None established.
Conventional products
A.malathion- Malathion 57EC
(3.2 pt/A). Use Malathion 57EC on currants
and gooseberries. An application of malathion is
recommended as the leaf buds are opening. OR
B.pyrethrin- Pyrenone
Crop Spray 0.5EC (2 12 oz/A) OR
C.*imidacloprid- *Provado
1.6F (3.75 fl oz/A) or *Pasada 1.6F
(3.75 fl. oz/A). OR
Symptoms- Currant stem girdler
is a sawfly that emerges in late April or early May. Adult sawflies lay eggs
in young, succulent shoot tips, then girdle tips below the eggs. Shoot tips
die, reducing cane length.
Management Options
Guideline
Scouting/thresholds
None established.
Resistant cultivars
None known.
Cultural management
Cut off affected tips below evidence
of insect activity.
Conventional
and
Organic
products
None known.
6.2.3
EARLY GRAPE TO BLOOM
6.2.3.1
White Pine Blister Rust
Symptoms- Leaf infections most
commonly appear mid-June to early Julyas small yellow to orange
cup-like spots (pustules) on less susceptible varieties, and larger
quarter-inch, angular, orange pustule patches on highly susceptible
varieties. These pustules produce spores that may re-infect Ribes throughout the summer. Infected plants are
weakened and may prematurely defoliate (drop their leaves). In fall, another
type of spore is produced on infected Ribes leaves.
These are released during cool, wet weather and infect the rusts alternate
host, five-needled pines (eastern white, whitebark,
limber, western white, sugar, bristlecone, foxtail, torrey
pines). Severe losses of timber (eastern white) pine have been recorded in
the past from this disease. For this reason, it is prohibited to grow
susceptible black currants in some areas of New York State.1
Management Options
Guideline
Scouting/thresholds
None established.
Resistant cultivars
Black currant Ben Sarek is resistant. Black currants Consort,
Crusader, Coronet and Titania are immune. Gooseberries, and red and white currants are generally
less susceptible. Ribes species Red Lake, Jumbo Cherry,
and white currant are known to be less susceptible than Red Jacket, Green Hansa, Poorman and Pixwell.
Cultural management
A.Plant only rust resistant or immune cultivars in regions where
susceptible pines are grown.
B.Plant susceptible currants and gooseberries at least 1 mile
from susceptible pines.
Conventional
products
A.paraffinic oil- JMS Stylet Oil (3 6
qt/100 gal) Test results in New York show this material is effective for rust
control if applied on a 7-day schedule at 200 psi spray pressure. Note:
Many pesticides are phytotoxic when applied with or
close to oil sprays. OR
B.##pyraclostrobin- Cabrio EG (14 oz/A) Begin applications prior to disease
development and continue on a 7-14-day interval. Use the shorter interval
when the disease pressure is high. Applications may be made up to the day of
harvest. To limit the potential for development of resistance, do not make
more than 4 applications (56 oz/A) of Cabrio or
other QoI (FRAC code 11) fungicides per season. Do
not make more than two (2) sequential applications of Cabrio
before alternating to a labeled fungicide with a different mode of action. Do
not enter the treated area with 24 hrs of the most recent application.
Organic
products
(May also be used in conventional
production.)
A.paraffinic oil- Organic JMS Stylet
Oil (3 6 qt/100 gal) Test results in New York show this material is
effective for rust control if applied on a 7-day schedule at 200 psi spray
pressure. Note: Many pesticides are phytotoxic
when applied with or close to oil sprays.
1The regulation on growing Ribes species in New York was revised in 2003. For
more information, see NYSDEC regulations located at: http://www.dec.ny.gov/regs/4079.html.
## = 2(ee)
recommendation based on quantitative efficacy data. Note: Any user
must have the 2(ee)
recommendation in his or her possession at the time of application,
e.g., Cornell Berry Guidelines.
6.2.3.2
Powdery Mildew
Follow guidelines under Burst to
leaf (section 6.2.2.1).
6.2.3.3
Currant Aphid
Follow guidelines under Burst to
leaf (section 6.2.2.2).
6.2.4
BLOOM TO PETAL FALL
6.2.4.1
White Pine Blister Rust
Follow guidelines under Early
grape to bloom (section 6.2.3.1).
6.2.4.2
Powdery Mildew
Follow guidelines under Burst to
leaf (section 6.2.2.1).
Symptoms- Both fungi
overwinter on dead leaves. Small brown spots appear on infected leaves in
early to mid June. At this point the 2 diseases are indistinguishable. Septoria leaf spots develop into large lesions with light
brown centers and darker borders. Small black specks (fruiting bodies) become
visible over the surface of the leaf spots. Anthracnose leaf spots are
smaller, dark brown, round to irregular spots with grayish fruiting bodies.
Currant fruit may also be infected by the anthracnose leaf spot fungus, which
causes black speck-like spots on fruit surfaces. Severely infected berries
may crack and drop. These diseases are especially devastating during wet
seasons. These leaf spots affect both currants and gooseberries.
Management Options
Guideline
Scouting/thresholds
None established.
Resistant cultivars
None known.
Cultural management
A.Reduce inoculum by removing dead leaves or
covering them with mulch prior to emergence of new leaves in spring.
B.Prune and trellis bushes to improve air circulation and promote leaf
drying.
C.Overhead irrigation creates conditions especially favorable for leaf
spot development. If overhead irrigation must be used, irrigate during
morning hours to allow foliage to dry before the evening.
Conventional products
A.copper hydroxide- Kocide 101 (10
lb/A) orKocide 4.5LF (6.67 pt/A) or Champ
Dry Prill (7 lb/A). OR
B.basic copper sulfate- Cuprofix
Ultra 40 Disperss (6.5 lb/A) applied before bloom
and after harvest.
Organic products
(May also be used in conventional production.)
A.copper hydroxide- Nu Cop 50 WP or Nu Cop 50DF (10 lb/A).
Make 3 applications, starting after harvest, before bloom, and after petal
fall. OR
B.copper sulfate- Basic Copper 53 (6 lb/A). Make 3 applications:
full bloom, 2 weeks later, and after harvest.
6.2.4.4
Currant Aphid
Follow guidelines under Early
grape to bloom (section 6.2.2.2).
6.2.4.5
Gooseberry Fruitworm
Symptoms- Adults lay eggs in Ribes
flowers. Larvae burrow into the berries, clustering the fruits and
even weaving portions of the stems together with silken webbing. These overwinter as pupae beneath soil or litter,
emerging in spring as adult moths. Gooseberry fruitworm
attacks gooseberries, currants, and most probably Jostaberries
as well.
Management Options
Guideline
Scouting/thresholds
None established.
Resistant cultivars
None known.
Cultural management
Shallow mechanical cultivation under
bushes can help expose and kill pupae.
Conventional products
No pesticides are currently
registered for control of gooseberry fruitworm in
NY State. However, their appearance may often coincide with currant fruitworm or Japanese beetles for which Malathion 5EC (1.6 pt) might be used. Control of these
concurrent pests should assist with gooseberry fruitworm
control.
Organic products
None known.
6.2.4.6
Imported Currant Worm
Symptoms- The full-grown larva
is 1.5 inches long; it is green with yellowish ends, has a black head, and is
covered with black spots. Shortly after the leaves are out in the spring, the
worms feed first in colonies and later singly, voraciously stripping the plants
of foliage. A second brood occurs in early summer, and a partial third brood
may appear depending on the weather.
Management Options
Guideline
Scouting/thresholds
None established.
Resistant cultivars
None known. Cultivars vary somewhat
in susceptibility but all Ribes (currants,
gooseberries, and Jostaberries) appear susceptible.
Cultural management
None established.
Conventional products
Chemical sprays should be applied as
soon as the worms appear. Note: Although these pests resemble other
lepidopteron worms, they are not related, and cannot be controlled
with Bacillus thuringiensis(Bt).
A.malathion- Malathion 57EC (3.2
pt/A).
Organic products
None known.
6.2.5
SUMMER PREHARVEST
6.2.5.1
White Pine Blister Rust
Follow guidelines under Early grape
to bloom (section 6.2.3.1).
6.2.5.2
Powdery Mildew
Follow guidelines under Burst to
leaf (section 6.2.2.1).
Follow guidelines under Bloom to
petal fall (6.2.4.3).
6.2.5.4
Gooseberry Fruitworm
Follow guidelines under Bloom to
petal fall (section 6.2.4.5).
6.2.5.5
Currant Borer
Symptoms- Yellowing of foliage
and leaf wilting during summer and fall. Clearwing moth adults lay eggs on
canes in late May. Pale yellow larvae attack canes in mid to late June,
boring in and tunneling up and down as the cane develops. The resulting
damage greatly weakens the cane so that it is capable of only sickly growth
or it may break off altogether. Red currants are most susceptible, but other
currants and gooseberries may also be attacked.
Management Options
Guideline
Scouting/thresholds
None established. Pheromone is
commercially available for monitoring male moths. Also, scout for the
appearance of the colorful (black and yellow) moth that mimics a wasp.
Resistant cultivars
None known.
Cultural management
Prune out and burn infested canes.
Conventional
and
Organic
products
None known.
6.2.5.6
Twospotted Spider Mite
Symptoms- Feeding by spider
mites causes white stippling and bronzing of leaves.
This damage is particularly apparent later in the season but can develop
anytime. When spider mites are present, you also may observe webbing. Look on
the underside of leaves for the tiny arthropods. Damage from spider mites
seems more frequent in warm, dry years. Regular monitoring is necessary for
assessing population growth.
Management Options
Guideline
Scouting/thresholds
None established, but over 60% of
leaves infested may be causing significant injury.
Resistant cultivars
None known.
Cultural management
A.Predatory mites, purchased from insectaries, can be released to help
control spider mites. Contact suppliers for assistance in determining release
rates and timing. In general, though, predatory mites should be released
early in the infestation to give them time to control the spider mites.
B.Maintain cover crops between rows to provide predator mite habitat.
Conventional products
A.bifenazate-Acramite 50WS (1.0 lb/A) for non-bearing currants.
Organic products
None known
6.2.5.7
Imported Currant Worm
Follow guidelines under Bloomto
petal fall (section 6.2.4.6).
6.2.5.8
Japanese Beetle
Symptoms- Beetles emerge in
early July and feed on leaves and fruit.
Management Options
Guideline
Scouting/thresholds
None
established.
Resistant cultivars
None
known.
Cultural management
None
established.
Conventional products
A.malathion- Malathion 5EC
(1.5 pts/100 gal or 3 pts/A). OR
Symptoms- These soft-bodied
mollusks resemble snails without a shell. Slugs
feed on leaves and fruit of all Ribes species. They
are most active at night and during cool, wet weather. Populations are
greatest when the weather is damp and the planting is mulched. Translucent
silver to whitish slime trails are visible on damaged plant parts.
Management Options
Guideline
Scouting/thresholds
None established.
Resistant cultivars
None known.
Cultural management
Eliminating mulch will reduce slug
populations, but will cause other problems, so this is not recommended.
A.Good sanitation and weed control helps to reduce slug populations.
B.In areas where slugs are a problem, avoid perennial legume clovers as
cover crops and rotate out of alfalfa or other perennial legumes 1 year prior
to planting establishment.
C.Overhead irrigation creates conditions especially favorable to slugs.
If overhead irrigation must be used, irrigate during morning hours to allow
foliage to dry before evening.
D.Pruning and trellising to improve air circulation.
Conventional
and
Organic
products
A.iron phosphate- Sluggo AG (20
44 lb/A). Spread bait around perimeter to intercept slug migrating towards
plots. If slugs are already in plots, carefully spread bait between the
furrows near the base of plants. Do not apply over the entire areas but apply
selectively. Apply higher rates if the infestation is severe or if the area
is heavily watered or after long periods of heavy rain. Reapply as bait is
consumed or at least every 2 weeks. Do not place in piles. Soil should be
moist with little or no standing water. If the ground is dry, wet before
applying bait.
