ESCA OF GRAPEVINES IN SOUTH AFRICA
Presented by Jan Booysen
Chana-Lee White
Francois Halleen and Lizel Mostert
Department of Plant Pathology

Faculty of Agriculture
What is Esca?
• Affects trunk and arms of older grapevines
• Disease complex producing overall syndrome
• 2 distinct diseases
• Wood rot
• Brown wood streaking
2
History of Esca in South Africa
•
•
•
•
3
Little information on Esca
Few incidences found
Only symptoms observed
Since 2001, Esca diseased vines have been
collected and causal fungi isolated
In the field…
4
Symptoms: Leaves
5
Symptoms: Leaves
6
Symptoms: Berries
7
Symptoms:
8
Symptoms: Apoplexy
9
Aims and Current Study
• Determine and characterize basidiomycetes
involved
• Identify other fungi involved
• Botryosphaeriaceae, Phomopsis, Phaeoacremonium,
Phaeomoniella
• Geographical distribution of species
10
Isolations
• Farms in the Western and Northern Cape visited
• Isolations
• Cultures selected
11
Distribution of esca diseased vines
ZIMBABWE
MOZAMBIQUE
NORTHERN
PROVINCE
LIMPOPO
BOTSWANA
MPUMALANGA
MPUMALANGA
GAUTENG
GAUTENG
NORTH WEST
NORTH
WEST
SWAZILAND
NAMIBIA
KWAZULU-NATAL
KWAZULU-NATAL
FREE STATE
FREE
STATE
LESOTHO
NORTHERN CAPE
NORTHERN
CAPE
EASTERN CAPE
EASTERN
CAPE
WESTERN
CAPECAPE
WESTERN
12
Age of vines sampled
4%
5%
23%
32%
1 - 10 years
11 - 20 years
21 - 30 years
31 - 40 years
40+ years
36%
13
Young Esca
• 2-year-old vine from Paarl
14
Organisms Involved
16
Basidiocarps
17
Basidiomycetes characterization
• 140 isolates used
• Sequencing of ITS region using ITS1 and ITS4
• New species identification
18
Phylogram of ITS
Heuristic search
1000 bootstrap
Fomitiporia
Innonotus
Inocutis
Unknown
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.
20
Outcomes
• Better understanding of Esca in South Africa
• Aid in development of control strategies
• Aid in developing early detection tools
21
Acknowledgements
• NRF and Winetech for funding
• Personnel at ARC-Nietvoorbji for technical
support
22