Powdery Mildew (Erisiphe necator) is a fungal infection which

lives on the surfaces of the vine with potential severe effects on

vine vigour and yield (Wilcox 2003; Creasy and Creasy 2009).

An obvious symptom is white/grey flag shoots early in the

season. On fruit and leaves evidence is found as a white/grey

powdery covering. On both sides of leaves, faint greeny-yellow

patches become dull grey, falling prematurely in autumn if

infections are severe which hits yield (Wilcox 2003). Dark

patches on canes and shoots go from grey to black. Younger

infected leaves grow distorted. Causing most economic damage:

berries split as epidermal cells are killed making growing grapes

inelastic. These grapes never ripen and taste bitter. Affected

vineyards have a characteristic musty, mushroomy aroma.

Reproduction is mostly asexual, with spores appearing 5-12

days after infection and spreading by rain splash or for long

distances on the wind. Germination is possible between 4-33oC.

In ideal growth conditions of 20-27oC (Creasy and Creasy

2009), >40% humidity, and shade (direct sunlight kills spores and

mycelium), the entire life-cycle happens in 5-7 days (Wilcox

2003). However powdery mildew can also germinate and grow

in drier conditions (20% humidity), and in spring requires only a

few mm of rain to start a primary germination, and secondary

infections require no further moisture (Wilcox 2003).

Temperatures above 32oC greatly restrict growth and spread of

infections (Wilcox 2003). Pictures of Powdery Mildew from

(Winetitles 2011; Wilcox 2003).

Downy Mildew (Peronospora) is a protist (fungal-like, but

with cell walls) which lives inside the vine tissues causing

premature leaf-fall and associated low vigour and yield.

Oily-looking spots appear on the upper surface of leaves

with corresponding downy whiteness of sporulation on

underside, usually along leaf veins. Infections often enter

and exit via under-leaf stomata, hence symptoms there.

Later the spots turn yellow-brown then browny-red

(limited by veins) then necrotic and leaves drop. Infected

shoots grow thick and distorted (‗shepherd‘s crook‘) and

downy white. Infected flowers desiccate and drop. Infected

berries go grey and dusty then brown and desiccated.

Downy mildew loves wet and humid conditions. Motile

oospores splashed from puddles for secondary infection.

Good soil drainage prevents puddling. Risky years are when

wet winters are followed by warm, stormy summers.

Secondary spore growth requirements: 18-23oC, humidity

95-100%, 4 hours of darkness; leaves wet of 2-3 hours

around dawn. Germination needs water droplet, and is

quicker at higher temperatures. Widespread infections

heralded by the 10:10:24 rule: 10oC and 10mm rain in 24

hours. Oil spots appear 5-14 days after this. It‘s important

to spray within 5-7 days if new spores seen on underside of

leaves.

Pictures of Downy Mildew from (Schwarz and Pearson

1984).

Botrytis (Botrytis cinerea), also called grey mould, is a fungal

infection which can severely affect vine yield. Although mostly

saprophytic, it can infect all parts of a living vine, and is especially seen

in berries. Botrytis affected berries cause off flavours and settling

problems in wine (Creasy and Creasy 2009). The damp climate means

there is little chance of seeing the benefits of ―noble rot‖ in the UK

which requires a combination of damp and dry conditions.

Infected leaves not serious: dull-green leaf spots 2-3cm diameter that

turn brown then necrotic. Infected canes have a grey dusting on

damaged canes, with greyish necrotic patches. Blossom blight can have

severe effects on yield, either killing inflorescences or becoming

sealed inside closing bunches from which infection then develops

(Creasy 2009). Most obvious/serious symptom: furry fungal berry

infections via the flower ovaries or through a weakness in the berry

epidermis, perhaps caused by other fungi (e.g. powdery mildew),

insect, bird or hail damage, or by the berries expanding causing the

cuticles to thin exposing micro-fissures. So thin-skinned varieties

more at risk (Pearson 1984) (e.g. Semillon, Chenin, Pinot gris,

Chardonnay, Muller-Thurgau &Riesling), also those with tight bunches.

The spores are spread by wind and rain. Does not need rain for

development, though humid conditions favour sporulation. Asexual

reproduction via conidiophores is most common. Germination is

possible 8-30oC, with humidity >90% and 6 hours of moisture.

Mycelium development requires humidity >50% and is favoured by

temperature >10oC and more optimally at 20-25oC (Creasy 2009).

Pictures of Botrytis from (Pearson 1984; Winetitles 2011).

VINEYARD IPM STRATEGY for South East England for the 5 major pests

2-3

leaves

Sh

oo

ts 2-4

cm

lon

g

First le

af

Leaf tip rosette Green tip Woolly bud Budswell Winter bud

Inflo

resc

en

ce c

lear

5 le

aves se

para

ted

8 le

aves se

parate

d

Com

pact flo

wer gro

ups

12 le

aves. D

eve

loped

inflo

resce

nce

. 16 le

aves. B

egin

nin

g

of flo

werin

g

Vin

e

Stre

et !

Flowering

30% caps off

Berries 4mm diam.

Bunches down

Berries>2mm dia.

Perpendicular bunches Flowering

80% caps off

50% caps off

17-20 leaves Berries 7mm diam.

Berr

ies

hard

&gre

en

Bu

nch

es

clo

sin

g

Berr

ies

en

larg

e

& c

han

ge c

olo

ur

Berr

ies

harvest

-rip

e

En

d o

f le

af

fall

Po

st-h

arvest

.

Can

es

matu

re

1 2 3 5 4

12

9

7

15

17

19

21 23 25 27 29 31

38

35

32

47

41

BUD BURST

SH

OO

TS

10cm

F

LO

WE

RIN

G

BE

GIN

S

FULL BLOOM SETTING PEA-SIZED

BERRIES

VE

RA

ISO

N

HA

RV

ES

T

StuartMcKenzieGraham@gmail.com. Plumpton College FdSc Wine Production, Christmas 2011

Pictures and descriptions of phenological stages; circled numbers are modified E-L number; major growth stages in BOLD (Coombe 1995)

Phomopsis is a fungal infection which affects canes, leaves and fruit. Severe

infections can lead to 10-40% crop loss (Pscheidt & Pearson 1991).

White-bleached canes with dark spots (fruiting bodies) are most obvious

symptom in the dormant season. These appear at lower internodes, lengthening

into 5-6mm cracks. Lower leaves can show small star-shaped spots (brown

centre with yellow rim) which then kills the leaf (Pscheidt and Pearson 1991).

These leaf spots appear 3-4 weeks after infection, with subsequent stem

damage. Berry symptoms (brown spots, then numerous fruiting bodies) are

possible but rare. No fungal eradicants available (Creasy and Creasy 2009).

Optimum infection: 10h rain then 8-10 hours of >96% humidity. Optimum

growth 23oC, though can grow in wider range of temperatures 1-37oC. Likes

high humidity and rain, with splashes spreading spore from black fruiting bodies

(Pscheidt and Pearson 1991). Symptoms appear 21-30 days post-infection.

Trunk diseases are a more newly recognised group of fungal diseases shown

to be major pathogens, such as Botryosphaeria, Cylindrocarpon and

Phaeoacremomium. Although phomopsis could also be included in this group,

this poster splits this group out since the pathogens are important and worthy

of the attention. Fungal wood infections are less well understood than other

pathogens. UK approved chemical treatments are only weakly effective.

Common symptoms are wood cankers (sectorial necrosis; v-shaped), lesions,

graft union failure, leaf chlorosis and fruit rot. Germination and growth occurs

in a wide temperature range; some wetness is required, humidity is correlated

with virulence. Infection spreads by wind and rain splash, but also direct from

nurseries and, importantly, into pruning wounds from secateurs, hence

importance of sterilising secateurs when and after dealing with infected vines.

Integrated Pest Management: stopping pests getting a monopoly on your vineyard

•Learn about the crop, the pest, the environment, and how they interact; know about symptoms and control options.

•Monitor the crop, the pest, the environment and the effectiveness of any treatment. Reduce sources of inoculum.

•Use chemicals in moderation to reduce impact on ecosystem and limit risk of resistance developing.

•Use an integrated combination of cultural and chemical strategies, being adaptable according to results of monitoring.

•Get out in the vineyard! The need for adaptability makes the phrase ‗IPM Programme‘ something of an oxymoron.

•Know the intervention and economic thresholds, and understand the economic realities of intervening or not.

•Manage proactively by predicting future disease pressures, and applying treatments before wet and humid periods.

This poster has been created without permission of Hasbro who make the excellent board game, Monopoly. If you like the poster, please buy the game.

Winter is not a time for

‘Free Parking‘:

• Sprayer maintenance and

calibration checking

nozzles and hoses

• Check disease records and

maps for hot-spots

• Order pesticides and

other chemicals

• Staff training

Pro

du

ct

Acti

ve

ingre

die

nt

L/h

a o

r kg/h

a

Pri

ce (

£/L

or

£/k

g)

£ / h

a /

ap

plicati

on

Est

. ap

pl.

per

year

£ / h

a /

year

Eff

ect

v

Bo

tryti

s

Eff

ect

v

Po

wd

ery

Eff

ect

v

Do

wn

y

Eff

ect

v

Ph

om

op

sis

v T

run

k

dis

ease

s

Max

ap

plicati

on

s

per

year

Harvest

inte

rval (d

)

Ris

k o

f

resi

stan

ce ALWAYS READ THE PRODUCT LABEL

Note: other branded products are available

and licensed in the UK with the same

active ingredients and can be interchanged.

Total cost per hectare £1,949

Teldor Fenhaxamid 1.50 £64 £96 1 £96 +++ 2 21 ++ Applications can‘t be successive.

Rovral Iprodione 3.00 £84 £253 2 £506 +++ 4 14 +++ High risk: non-persistent resistance.

Switch Cyprodinil+fludioxinil 0.60 £107 £64 1 £64 +++ ++ + + 2 35 ++ Don't use with/close to Switch, or risk resistance

Serenade Bacillus subtilis 10.00 £12 £122 7 £853 +++ ++ 7 day interval - - Inhibition through competition; also stimulates

vine defences

K bicarb Potassium bicarbonate (food gr) 5.00 £2 £9 3 £26 ++ - - - As knock-down. Avoid during flowering.

Kindred Meptyldioncap 0.60 £32 £19 2 £38 +++ 4 21 + Broad spectrum. Avoid during flowering.

Indar Fenbuconazole 1.20 £31 £37 1 £37 +++ + 8 21 ++ Handling concentrate requires +PPE.

Systhane Myclobutanil 0.24 £87 £21 1 £21 +++ + 1.92 L/ha 14 ++ DMI

Nativo Tebuconazole + trifloxystrobin 0.18 £106 £19 1 £19 ++ +++ + ++ ++ 2 35 ++ Best to use at early disease stages

Karamate Mancozeb 2.00 £7 £14 2 £29 +++ ++ + 4 56 + Stimulates growth. 25mm rain washes off.

Valbon Benthiavalicard-isopropyl +

mancozeb 1.60 £12 £20 1 £20 +++ ++ 2 56 +

Phyte P Plus Potassium phosphite 4.00 £7 £28 5 £142 +++ + - - - Cheap, low toxicity

Headland

copper Copper oxychloride 5.00 £7 £33 2 £66 + +++ + - - -

Spray when dry; toxic in cold conditions. Don't

use at flowering or too close to harvest else risk

delayed ripening, and fermentation problems.

Kumulus Sulphur 2.50 £2 £5 7 £32 + +++ + ++ + 10 day

interval

30

(rec) -

Very broad spectrum. Safe and cheap. Temp >18C

(needs to vapourise) and <30C (will scorch).

Avoid at flowering. Don't use too close to harvest

else risk ferment probs and hydrogen sulphide in

wine. Works by coverage and rain washes off.

Works Cited

• Bonomelli, A., Mercier, L., Franchel, J. et al. (2004) 'Response of Grapevine Defenses to UV—C Exposure', American Journal of Viticulture

and Enology, vol. 55, pp. 51-59.

• Coombe, B.G. (1995) 'Adoption of a system for identifying grapevine growth stages', Australian Journal of Grape and Wine Research, vol. 1,

pp. 100-110.

• Creasy, G.L. and Creasy, L.L. (2009) Grapes, Cambridge MA, Cabi.

• Graham, S.M. (2011) Trunk disease in UK Vineyards, [Online], Available: http://kenziewine.wordpress.com/2011/12/28/trunk-disease-in-uk-

vineyards/ [date accessed 28 December 2011].

• Jackson, R.S. (2008) Wine science: principles and applications, 3rd edition, Burlington, Academic Press.

• Kovach, J. and Weigle, T. (1995) Grape IPM in the Northeast, New York State Integrated Pest Management Program, [Online], Cornell Uni

Overwintering. Powdery: on bark and dead leaves, and also in buds (Jackson 2008), the

latter causing white/grey flag shoots about 3-8 weeks after budburst (stages 9-15). Downy:

Overwinters in vineyard debris. Botrytis: Overwinters as mycelium both in vineyard debris and on

vines and mummified berries (Creasy and Creasy 2009), then further colonises dead tissue in the

spring. Phomopsis: Overwinters on the vine in canes and on bark (Pscheidt and Pearson 1991).

Bo

trytis - Delay first sp

ray till flow

erin

g if weath

er is d

ry, or ju

st

pre

-flow

erin

g if wet (so

monito

r weath

er b

efo

re flo

werin

g). Only

appears p

re-flo

werin

g in ve

ry dam

p co

nditio

ns, b

ut if so

infe

ction

can cau

se in

flore

scence

s to d

rop o

ff and in

flow

ers le

ads to

poor

pollin

ation/fru

it-set an

d in

ocu

lates b

unch

es, h

ence

poor yie

ld.

Bo

tryt

is:

most

cr

itic

al

tim

e

for

monitori

ng

and tr

eat

ment

since

can infe

ct c

losi

ng

bunch

es

Botrytis: critical time for monitoring and treatment

Bo

tryt

is: m

ost

obvi

ous

sign

is

grey

rot

on b

err

ies

afte

r

vera

ison

and

esp

eci

ally

to

war

ds

har

vest

, w

ith

the

appear

ance

of

fluffy

conid

ia

in

dam

p

conditio

ns.

Infe

ctio

n o

ften s

pre

ads

from

berr

y in

centr

e o

f cl

ust

er.

Powdery: monitor for poor fruit set Powdery: monitor for split berries

Pow

dery - E

arly seaso

n w

arm te

mperatu

res w

ill incre

ase d

isease

pre

ssure

(Wilco

x 2

003). Y

oung le

aves m

ore

susce

ptib

le to

infe

ction th

an o

ld o

nes

(Wilco

x 2

003). M

onito

r from

stage 9

and 1

2 sin

ce sp

ray may e

ven b

e re

quire

d th

is early in

seaso

n, an

d sp

raying sh

ould

not b

e d

elaye

d u

ntil b

loom

(Wilco

x 2

003). 8

0%

caps o

ff is a key m

onito

ring stage

. Afte

r that it‘s still m

onito

ring w

eath

er, b

ut m

onito

ring fo

r sympto

ms o

n b

errie

s.

Powdery - Last spray

application at post-

veraison stage.

Powdery: Important to treat properly during the period of maximum susceptibility from pre-bloom to 4-weeks post-bloom (Wilcox 2003),

though after this infections can then be severe in that they predispose berries to a subsequent botrytis infection (Wilcox 2003).

•Pow

dery: m

onito

r from

stage9. In

fecte

d b

uds le

ad to

white

/grey flag

shoots ab

out 3

-8 w

eeks afte

r budburst (stage

s 9-1

5).

•Dow

ny: m

onito

r from

stage12 till b

errie

s pea-size

d.

•Bo

trytis: monito

r from

stage12 righ

t thro

ugh

till harve

st.

•Sam

ple

. Watch

ing fo

r wet &

hum

id w

eath

er, an

d fo

r leaf sym

pto

ms.

Downy - Remove water

shoots growing low on

trunk since these are more

at risk to infection from

splashing.

Phom

opsis - start m

onito

ring

3 w

eeks afte

r budburst, th

en

eve

ry 1-2

weeks. S

tart

sprayin

g from

3cm

grow

th

till fruit se

t.

Phom

opsi

s: si

gns

of

lesi

on

s o

n r

ach

is a

nd

fr

uit

ro

t m

ay s

tart

to

ap

pe

ar 1

-3 w

eeks

pre

-h

arve

st.

Summarised spray programme from diagram above

~week Stage Powdery Downy Botrytis Phom’sis & Tk.Dis

7 FirstLeaf Kindred

12 5 leaves Indar Karamate Nativo, Karamate

19 16 leaves; flowering start Systhane Valbon Teldor Valbon

25 80% caps Headland copper

27 Setting Kindred Rovral

29 Berries 4mm diam Karamate Karamate

33 Berries hard and green Headland copper Switch

35 Veraison Rovral

Sp

ray K

ind

red

S

pra

y In

dar &

Kara

mate

S

pra

y S

ysth

an

e,

Valb

on

& T

eld

or

Spray Headland

Copper

Spray Kindred &

Rovral

Spray Karamate

Sp

ray H

ead

lan

d

Co

pp

er

& S

wit

ch

S

pra

y R

ovra

l

Do remember to

train all staff to

make pest

management both

safe and effective

No need to mortgage property

to pay for excessive spray

programmes – a well designed,

integrated pest management

strategy will yield positive net

financial results.

How to monitor

• In the field use a 10x hand lens.

• Focus on areas of the vineyard with previous history of disease, and damp and high-vigour

places which are more susceptible. Even powdery mildew is stronger in damp areas.

•Tag and map infected areas for treatment and for records for future use, including record of

extent and date. Can be used to computer model epidemiology hence improve future pest

management.

• Sample fixed number of vines and extrapolate to estimate vineyard infection rate. Record

data for future reference.

Powdery: monitor every 2 weeks. 200 vines, leaves and bunches. Bag infected material

before and after spraying, and compare after 5-7 days.

Downy: place samples in plastic bag >13oC for 1 day – will see spores appear if infection

present. A single oil-spot can lead to a significant infection, so careful monitoring important.

Botrytis: place samples (leaves, flower clusters or bunches in damp plastic bag at 20oC for 1-

3 days and look for characteristic grey mould.

Phomopsis: monitor during growing season, especially if it has been wet. Monitor in

dormant season by looking for white canes.

Trunk disease: monitor throughout year – best to look before leaves drop (UKVA 2011).

Cut into wood to investigate and look for necrosis if infection suspected.

IPM vineyard culture – building IPM on a sound foundation

Use cultural techniques first, then chemical as last resort. Monitoring is key to limiting the

application of chemicals to minimal levels; to understand the vineyard and to spot disease as

early as possible;. Taking samples before and after spraying indicates the effectiveness of

treatments. Some examples of important cultural techniques (Creasy and Creasy 2009):

• Vineyard establishment: low vigour rootstocks; avoid high density planting; consider

planting parallel to prevailing wind. Only use certified nurseries.

• Encourage deep rooting hence moderate of water uptake, e.g. for botrytis v berry splitting.

• Remove infected leaves, shoots, wood and mummified berries. Remove all debris from

vineyard, take down-wind and burn to destroy any inoculums. 90% of vineyard debris can

be infected with Botrytis (Creasy&Creasy 2009). Includes removing badly infected vines!

• From 80% caps off, trim canopy to improve air circulation (reduces humidity and hence

disease) and allow better spray penetration, though mechanical trimming can make vines

susceptible to more infection (Pscheidt and Pearson 1991). Also consider leaf-stripping.

• Do not use excessive nitrogen-based fertiliser since this causes over vigorous, shady and

humid canopy. Also use cover crops to reduce vigour (Creasy and Creasy 2009).

• Exposing berries to sunlight (canopy management) strengthens skins v botrytis. Stilbenes

(e.g. reservatrol) produced in vines acts as protector, and production is stimulated by UV

light (Bonomelli,Mercier et al.2004; Creasy&Creasy 2009) and by low nitrogen (low vigour)

• Practice minimum tillage (promotes soil macro and micro flora and fauna).

In addition to the specific spraying above, regular spraying as follows:`

• Serenade every 4 weeks from Stage5 (rosette)-harvest

• Kumulus every 3 weeks from Stage9 to veraison. Also apply after heavy rain since it is a

surface treatment hence washes off. Only if >18oC, K bicarb if colder. No Kumulus or K

bicarb at flowering.

• Phyte P Plus every 4 weeks from 8 leaves - berries hard and green

• Add SL567A if Downy symptoms (high risk of resistance developing)

This varied spray program aims to limit multiple applications of pesticides from single families

to reduces the risk of resistance, e.g. DMIs (Creasy and Creasy 2009).

Try to anticipate wet and humid conditions and spray before they happen.

Install a weather

station. Build a

multi-year picture

of disease v

weather; use

computer

modelling to

forecast infection.

Keep records.

Models are

typically based on

weather:

cumulative

wetness and

temperature,

within threshold

levels.

Reducing vine stress is a key

IPM way to fight disease by

letting the vines best employ

their own natural defences, e.g.

against botryosphaeria

(Graham 2011).

For trunk diseases it may be

possible in light infections

to remove all infected wood

and 5cm extra down trunk

and retrain new trunk from

water shoot.

Sp

ray N

ativ

o

Water excess

and deficit are

examples of

stress which can

predispose vines

to infection.

Downy: keep monitoring till berries are pea-sized. Powdery: keep monitoring till veraison. Botrytis: keep monitoring right through till harvest.

Trunk diseases Phomopsis Downy mildew Powdery mildew

Botrytis

Don‘t spray sulphur, K bicarb, copper or

Kindred during flowering or fruit set suffers

• Pearson, R.C. (1984) 'Botrytis bunch rot and blight, Disease Identification Sheet', Cornell University, vol. 3, pp. 1-2.

• Pscheidt, J.W. and Pearson, R.C. (1991) 'Phomopsis cane and leaf spot of grape, Disease Identification Sheet', Cornell Cooperative Extension,

vol. 6, pp. 1-2.

• Schwarz, M.R. and Pearson, R.C. (1984) 'Downy Mildew, Disease Identification Sheet', Cornell University, vol. 5, pp. 1-2.

• UKVA (2011) 'Grapevine Trunk Diseases', UKVA Bulletin, vol. 50, November.

• University of California (2011) UC IPM Online, Grapes, [Online], University of California Agriculture & Natural Resources, Available:

http://www.ipm.ucdavis.edu/PMG/selectnewpest.grapes.html [date accessed 12 December 2011].

• Wilcox, W.F. (2003) 'Grapevine Powdery Mildew, Disease Identification Sheet', Cornell Cooperative Extension, vol. 102GFSG-D2, pp. 1-3.

• Winetitles (2011) Disease Diagnosis, [Online], Winetitles, Available: http://www.winetitles.com/diagnosis/ [date accessed 21 December 2011].

Don‘t take a

chance: keep

monitoring;

keep vigilant;

keep planning

ahead.

Botrytis, Downy &

Powdery Mildew

and Phomopsis are

the major fungal

concerns for

vineyards

worldwide (Creasy and Creasy 2009)

These major

fungal pests are

endemic and the

focus has to be

on management,

not eradication

(Creasy and Creasy 2009)

Now is the

time to start

considering

starting a

trimming

and/or leaf

stripping

strategy

(Creasy &

Creasy 2009)