DISEASES OF GRAPEVINE
1 Downey Mildew

: Plasmopara viticola

2 Powdery Mildew

: Uncinula necator

(Oidium tuckeri)
3 Anthracnose

: Gloeosporium ampelophagum

1. Downey Mildew
C.O.
: Plasmopara viticola
Class : Oomycota
Order : Peronosporales
Family : Peronosporaceae

Economic importance:
Since 1875, this disease caused heavy losses to wine

industry in France
It led to discovery of Bordeaux Mixture(copper
sulphate (CuSO4) and quicklime (CaO) by Prof.
Pierre- Marie-Alexis Millardet in 1878

Symptoms:
➢ Symptoms appear on all aerial and tender parts of
the vine.
➢ Symptoms are more pronounced on leaves, young
shoots and immature berries
➢ Irregular, yellowish, translucent spots limited by
veins appear on upper surface of leaves
➢ Correspondingly on the lower surface dirty
white,downy growth of fungus appears
➢ Affected leaves become yellow and brown and
drieddue to necrosis
➢ Premature defoliation
➢ Dwarfing of tender shoots
➢ Infected leaves, shoots and tendrils are covered by
whitish growth of the fungus

➢ The disease may also spread to the floral parts
➢ The infected flower dies and drops away
prematurely.
➢ White growth of fungus on berries, which
subsequently becomes leathery and shrivels.
➢ Infected berries turn hard, bluish green and then
brown
➢ Later infection of berries results in soft rot
symptoms.
➢ Normally, the fully grown or maturing berries do
not contact fresh infection as stomata turn nonfunctional
➢ No cracking of the skin of the berries
➢The juice quality of fruit is reduced

Favourable condition:
✓ Optimum temperature : 20-22°C
✓ Relative humidity : 80-100%
✓ High soil moisture

Disease cycle:
• PSI: Oospores present in the infected leaves, shoots
and berries. Also as dormant mycelium in infected
twigs
• SSI: Sporangia or zoospores by wind, rain and
insects

Management:
➢ Field sanitation by collection and burning of fallen
leaves and twigs
➢ Vine should be kept high above ground to allow
circulation of air by proper spacing
➢ Pruning (April-May & September-October) and
burning of infected twigs
➢ Targeted pruning to improve air circulation slows
down disease progression
➢ Grow resistant varieties like Amber Queen,
Cardinal,Champa, Champion, Dogridge and Red
Sultana

Management:
➢ The disease can be effectively managed by giving 3-5
prophylactic sprays with Bordeaux mixture 1% or
fosetyl-Al (Aliette) 0.2% or curative spray with
metalaxyl + mancozeb (Ridomil MZ 72) 0.2% or
Azoxystrobin 0.1%
➢ Spray schedule with Bordeaux mixture 1% and other
chemicals
1. Immediately after pruning of vines
2. When new flush is formed (3-4 weeks after
pruning)
3. Before buds open
4. When bunches or berries are formed
5. During shoot growth

History of invention of BM:
After the downy mildew had struck, botany professor PierreMarie-Alexis Millardet of the University of Bordeaux studied

the disease in vineyards of the Bordeaux region. Millardet then
noted that vines closest to the roads did not show mildew, while
all other vines were affected. After inquiries, he found out those
vines had been sprayed with a mixture of CuSO4 and lime to
deter passersby from eating the grapes, since this treatment was

both visible and bitter-tasting. This led Millardet to conduct
trials with this treatment.
Millardet published his findings in 1878, and recommended the
mixture to combat downy mildew.

2. Powdery Mildew
C.O.
: Uncinula necator (Oidium tuckeri)
Class : Leotiomycetes
Order : Erysiphales
Family : Erysiphaceae

Economic importance:
Losses in yield of fruits may be up to 40-60%.
In addition to loss of yield, infected berries tend to
have higher acid content than healthy fruits and are
unsuitable for wine making.
First reported from England and later on from France
Distribution: Italy, Australia, Greece, Hungary, Syria,
USA and India

Symptoms:
➢ Small
whitish
patches
appear on both the surfaces
of young leaves, stems,
flowers and fruits.
➢ These patches enlarges
covering whole leaf surface
with characteristic whitish
powdery coating
➢ The infected leaves turn
grayish
white,
become
dwarfed,
twisted
and
malformed

➢ The infected stem become
grey, turn dark brown
➢ If the blossom is affected, a
grayish
white
powdery
growth appears on the floral
parts and the flowers may
drop
➢ The entire inflorescence may
appear
discolored
and
barren.

➢ The affected berries
become
malformed
with grayish to dark
brown patches on the
skin
➢ The skin of affected
berries cracks and the
pulp is exposed

Favourable condition:
✓ Cool dry weather
✓ Maximum temperature in the range of 27-31oC
with R.H. up to 91% favour disease incidence
(November and December)

Disease cycle:
• PSI: Through dormant mycelium in
cleistothecia and conidia present in the
infected shoots and buds
• SSI: Through air-borne conidia

Management:
➢ Clean cultivation of vines or removal and destruction
of all diseased parts
➢ Dustings of vines with 300 mesh sulphur (1st when
new shoots are 2 weeks old, 2nd prior to blossoming,
3rd when the fruits are half ripe)
➢ Prophylactic spray with B.M. 1% or lime sulphur at
dormant stage delays development of diseaseSpray
wettable sulphur @ 0.3% or dinocap or tridemorph
@ 0.1%
➢ Oxythioquinox (Morestan) @ 0.03% sprayed at 4
days interval starting from last week of December to
1st week of March
➢ Grow resistant varieties like Chholth Red, Chholth
white, Skibba Red, Skibba White

3. Anthracnose/Bird’s eye spot
C.O.
: Gloeosporium ampelophagum
Class : Dothideomycetes
Order : Myriangiales
Family : Elsinoaceae

Economic importance:
In India, anthracnose was first recorded in 1903 near
Poona by E. J.Butler
Distribution: Europe, South Africa, USA, West
Australia, France
India:- A.P, U.P,M.S, T.N, Haryana, Karnataka,
Punjab and Rajasthan
Loss:-10-15 % losses recorded from Punjab and
Haryana

Symptoms:
➢ The fungus affects the
stem

,

young

shoots,

leaves and berries
➢ Small circular spots with
grayish black centers and
yellow

margin

produced on the leaves

are

➢ On the stem and
young shoots irregular
black spots develop,
which later enlarge to
form
cankerous
growths
➢ Characteristic round,
brownish , sunken
spots
resembling
bird’s eyes appear on
the berries and hence
the name bird’s eyes
➢ The infected berries
rots

On leaves

Circular, sunken
spots

On twigs

Spots in advanced
stage

On bunches

On fruits

Favourable condition:
✓ Warm wet weather with continuous drizzle of rain
and windy weather for 2-3 days
✓ Low lying and ill drained soils
✓ Anab-e-Shahi variety is susceptible.

Disease cycle:
• PSI: Survives as dormant mycelium in the
infected stem cankers
• SSI: Wind borne and rain splashed conidia

Management:
➢ Removal of infected twigs
➢ Selection of cuttings from disease free areas and
dipping them in 3% FeSO4 solution for 30 minutes
before planting.
➢ Spraying Bordeaux mixture 1% or CoC @ 0.25% or
carbendazim @ 0.1% or mancozeb75 wp @ 0.2% or
difolatan 75 wp @ 0.2% or chlorothalonil 75 wp @
0.2% or baycor 25 wp @ 0.1% found effective.
➢ Varieties like Bangalore blue, Golden Muscat, Golden
queen and Isabella are resistant