Reading...
Play button
Play button
Use LEFT and RIGHT arrow keys to navigate between flashcards;
Use UP and DOWN arrow keys to flip the card;
H to show hint;
A reads text to speech;
19 Cards in this Set
- Front
- Back
|
What are the 4 categories of Vine Disease
|
Fungal
Viral Bacterial Photoplasma |
|
|
How do Fungal issues manifest?
|
Mold or mildew (warmer (damp) climates)
|
|
|
How is Viral disease transmitted?
|
Grafting or by insect
|
|
|
List 6 Fungal Disease
|
Powdery Mildew (Iodium)
Downy Mildew (Pernospora) Eutypa Dieback Esca (Black Measles) Black Rot Bunch Rot |
|
|
What is Powdery Mildew?
|
(Iodium) -
-Native to NA -Thrives in humid dry conditions -effects green parts of vine, dusts them w/white powder -inhibits bunch development & ripening -combat-sulphur & insecticides |
|
|
What is Downy Mildew?
|
(Peronospora)
-the agent of it is (Plasmopara Viticola) -Spread Europe to NA -attacks green parts of vine (leaves fall off) -appears as 'oil spot' -combat w/Bordeaux Mixture (copper sulphate water & lime |
|
|
What is Eutypa Dieback?
|
"Dead Arm"
-caused by Eutypa lata fungus -spores carried by rain-enter through pruning wounds -Mediterranean climates -effects yield, not quality -stunted shoot growth as fungus releases toxins |
|
|
What is Esca?
|
(Black Measles)
-warmer climates -result of a complex of fungi -no known cure or combat -spread by water or pruning shears -softens core of wood |
|
|
What is Black Rot?
|
Native to NA
-transported to EU with Rootstock for Phylloxera -caused by Guignardia bidwelli fungus -controlled through fungus sprays |
|
|
What is Bunch Rot?
|
-grouping of similar diseases
-reduces crop yield-creates a 'moldy' taste in wine -most common form -"Botrytis bunch rot" -can be favourable in White BA needs at least 90% humidity |
|
|
List 3 Bacterial Disease
|
Pierce's Disease
Crown Gall (Black Knot) Bacterial Blight |
|
|
What is Pierce's Disease?
|
Caused by bacteria Xylella fastidiosa
-transmitted by sharpshooters -renders vines incapable of producing chlorophyll (2-5 yrs) -no cure or chemical control |
|
|
What is Crown Gall?
|
(Black Knot)
-caused by bacteria : Agrobacterium tumefaciens -creates tumors on stock (knot) -strangles the vine -cooler climates |
|
|
What is Bacterial Blight?
|
Casued by the bacteria : Xanthomonas ampelina
-kills young grapevine shoots -develop brown streaks in early Spring -spread by rain & pruning tools -controled by hot water sprays or Bordeaux Mixture |
|
|
List 2 Viral Disease
|
Leafroll Virus
Fanleaf Degeneration |
|
|
What is Leafroll Virus?
|
-condition caused by a complex of at least nine different viruses
-may be responsible for as much as 60% of world’s grape production losses -affected vines display radiant shades of red and gold in the autumn -characteristic downward curling of the leaves -reduced yields and delayed ripening -spread through propagation of infected vines or by an insect vector like the mealy bug -currently incurable but it will not kill the vine |
|
|
What is Fanleaf Degeneration?
|
a “nepovirus” spread by soil nematodes feeding on infected roots.
-severely curtails yields and affected vineyards must be removed. -A complex of similar diseases, it deforms shoot growth, and leads to poor fruit set and shot (seedless) berries. -The leaves on an infected vine are malformed, resembling fans in appearance, and may form yellow bands around the veins. The productive lifespan of the vine and its winter durability diminised |
|
|
List a Phytoplasma Diseases
|
Flavescence Dorée
|
|
|
What is Flavescence Dorée?
|
-form of grapevine yellows
1st appeared in Armagnac in 1949 -Leafhopper insects and propagation of infected vines spread the disease -delay budbreak and slow shoot growth, eventually causing bunches to fall off the vine and berries to shrivel -disease will discolor leaves, cause pustules and cracks to form, and may kill young vines -No cure exists, although insecticides may help |
