Department of Plant Pathology

Faculty of Agriculture

ESCA OF GRAPEVINES IN SOUTH AFRICA

Chana-Lee WhiteFrancois Halleen and Lizel Mostert

Presented by Jan Booysen

2

What is Esca?

• Affects trunk and arms of older grapevines • Disease complex producing overall

syndrome• 2 distinct diseases

• Wood rot • Brown wood streaking

3

History of Esca in South Africa

• Little information on Esca• Few incidences found• Only symptoms observed• Since 2001, Esca diseased vines have

been collected and causal fungi isolated

4

In the field…

5

Symptoms: Leaves

6

Symptoms: Leaves

7

Symptoms: Berries

8

Symptoms:

9

Symptoms: Apoplexy

10

Aims and Current Study

• Determine and characterize basidiomycetes involved

• Identify other fungi involved • Botryosphaeriaceae, Phomopsis,

Phaeoacremonium, Phaeomoniella

• Geographical distribution of species

11

Isolations

• Farms in the Western and Northern Cape visited

• Isolations • Cultures selected

12

Distribution of esca diseased vines

MPUMALANGA

SWAZILAND

EASTERN CAPE

KWAZULU-NATALFREE STATE

LESOTHO

WESTERN CAPE

BOTSWANA

NAMIBIA

NORTHERN CAPE

NORTH WEST

ZIMBABWE

GAUTENG

NORTHERN PROVINCE

MPUMALANGAMPUMALANGA

SWAZILANDSWAZILAND

EASTERN CAPEEASTERN CAPE

KWAZULU-NATALKWAZULU-NATAL

FREE STATEFREE STATE

LESOTHOLESOTHO

WESTERN CAPEWESTERN CAPE

MOZAMBIQUEMOZAMBIQUE

BOTSWANABOTSWANA

NAMIBIANAMIBIA

NORTHERN CAPENORTHERN CAPE

NORTH WESTNORTH WEST

ZIMBABWEZIMBABWE

GAUTENGGAUTENG

LIMPOPOLIMPOPO

13

Age of vines sampled

5%

32%

36%

23%

4%

1 - 10 years

11 - 20 years

21 - 30 years

31 - 40 years

40+ years

14

Young Esca

• 2-year-old vine from Paarl

16

Organisms Involved

17

Basidiocarps

18

Basidiomycetes characterization

• 140 isolates used • Sequencing of ITS region using ITS1 and

ITS4 • New species identification

Phylogram of ITSHeuristic search1000 bootstrap

FomitiporiFomitiporiaa

InnonotusInnonotus

InocutisInocutis

UnknownUnknown

20

Conclusions

• Esca is widespread on grapevines in SA, occurring mostly on grapevines of 10yrs and older

• A species-complex of 7 Basidiomycete species

• Predominant species: Inocutis sp.Fomitiporia sp.

21

Outcomes

• Better understanding of Esca in South Africa

• Aid in development of control strategies • Aid in developing early detection tools

22

Acknowledgements

• NRF and Winetech for funding• Personnel at ARC-Nietvoorbji for technical

support