Diseases

Question 1

Name the common fungal diseases

Answer 1

Powdery Mildew
Downy Mildew
Eutypa Dieback
Esca
Black Rot
Bunch Rot

Question 2

Name the common bacterial diseases.

Answer 2

Pierce’s Disease
Crown Gall (Black Knot)
Bacterial Blight

Question 3

Name the Viral diseases.

Answer 3

Leafroll Virus

Fanleaf degeneration

Question 4

Name the most common Phytoplasma Disease.

Answer 4

Flavescence Doree

Question 5

What is Powdery Mildew?

Answer 5

It affects the green parts of the leaf and survives in hot, arid climates.

Question 6

What is Downy Mildew?

Answer 6

It does not survive in hot, arid climates. Can be cured with the “Bordeaux Mixture” copper sulfate, water and lime.

Question 7

What is Eutypa Dieback?

Answer 7

It is a bacterial disease - dead arm. Enters the pruning wound. Very common in Medditerean climates. Kills the cordon. Infects numerous vines symoltaneously.

Question 8

What is the fungal disease Esca?

Answer 8

Result of a complex of fungi. Causes the inside of the vine to rot. Romans used to love trees with it because they caught fire quickly.

Question 9

Black Rot?

Answer 9

Fungal disease, black spots on the vine’s leaves and can be controlled with the use of fungal spray. It’s an american import disease.

Question 10

What is the fungal disease bunch rot?

Answer 10

Includes Botrytis Cinerea

Question 11

What is the bacterial diesease Pierce’s Disease?

Answer 11

It is carried by a glass-winged sharpshooter. A scourge, preventing the vine to produce Chlorophyll. Kills in 1-5 years.

Question 12

What is the Crown Gall disease?

Answer 12

A bacterial disease, also known as Black Knot. The disease causes big tumors on the trunk of the vine causing strangulation.

Question 13

What is Bacterial Blight?

Answer 13

Often kills young grapevines. is spread through unclean pruning tools. Can be controlled by hot water an the bordeaux mixture.

Question 14

What is the leafroll virus?

Answer 14

Caused by a complex of at least nine different virus’s and causes 60% of vine loos around the world. Currently incurable. causes vibrant colors in the fall with the downturning at the edges of the leaves.

Question 15

What is Fanleaf degenration?

Answer 15

Caused by a nepovirus spread by soil nematodes that feed on the roots. Vine must be removed. Characterized by yellow vines in the green leaves.

Question 16

What is Flavescence Doree?

Answer 16

It is a phytoplasma Disease. Leafhopper insects spread the disease. Delay bud break and slow shoot growth. Leaves will discolor. Currently there is no cure.

Question 17

What kind of fementations do small vessels lead to?

Answer 17

longer, cooler ferments. Larger vessels hotter, shorter ferments.

Question 18

What is the living range temperature wise for yeasts?

Answer 18

50 degrees F to 113 degrees

Question 19

What is a culprit of Volatile acidity in the end product of a wine?

Answer 19

Trace presence of Acetaldehyde left in the new wine will inevitably be converted into acetic acid which then comes in contact with alcohol and is converted to ethyl acetate a culprit of volatile acidity.