Diseases and Pest

Question 1

What are the three large categories of Diseases

Answer 1

Fungal, Bacterial, Viral

Question 2

Second name for Powdery Mildew

Answer 2

Oidium

Question 3

Where is Powdery Mildew native from

Answer 3

North America

Question 4

What conditions cause Powdery Mildew to thrive?

Answer 4

warm, damp conditions; 70-85degrees F spores are carried by the wind to infect green plant tissue

Question 5

When is Powdery Mildew the most detrimental?

Answer 5

from Budbreak to Veraison

Question 6

What damage occurs due to Powdery Mildew

Answer 6

small web-like fuzzy pathes on leaves and fruit; black scarring on canes

Question 7

Most common ways to keep powdery mildew at bay?

Answer 7

spraying sulfur/ Bordeaux Mixture (10-14days); Systemic Fungicides(21 days); Biological Fungicides (7 days); canopies with good airflow

Question 8

What varieties are susceptible to Powdery Mildew?

Answer 8

Cab Sav, Carignan, Chardonnay

Question 9

What is the other names from Downy Mildew

Answer 9

Mildiou, Peronospora

Question 10

What are the conditions needed for Downy Mildew to grow?

Answer 10

65-77degrees; only spreads through water; regions that have good summertime rain are impacted

Question 11

Signs of Downy Mildew

Answer 11

attacks green plant tissue, especially young shoots and leaves
Causes Oily yellow spots on leves
cripples growing shoots and leads to defoliation and shut down the vines
Turns berries green/grey or pinkgrey and shrivel

Question 12

How to keep Downy Mildew at bay

Answer 12

Bordeaux Blend every 2 weeks

Question 13

What is the Bordeaux Blend

Answer 13

copper sulfur mixture

Question 14

Examples of Bunch Rot diseases

Answer 14

Botrytis Cinerea, Sour Rot

Question 15

What is Sour Rot

Answer 15

Caused by yeast and bacteria that colonized damaged fruit and produces vinegar flavors

Question 16

When does Bunch Rot diseases tend to occur?

Answer 16

During flowering; Spores become trapped and lie dormant until veraison (when sugars start to form)

Question 17

Examples of Trunk Disease

Answer 17

Esca, Botryosphaeria, Eutypa Dieback

Question 18

What causes Trunk Diseases

Answer 18

Fungal spores that enter the vine through pruning wounds

Question 19

What is the symptom of Trunk Diseases

Answer 19

trunk and cordon decay; the vine cant transport water and nutrients to the vines extremities

Question 20

Eutypa dieback

Answer 20

-Trunk disease
-Typically affects one single spur, before advancing through the vine
-Causes stunted shoots, shriveled fruit, & small cup shaped chlorotic leves

Question 21

Botryosphaeria

Answer 21

-Trunk Disease
-Pie Shaped wedge inside the permanent wood
-Shoots on vines are undersized

Question 22

Esca disease

Answer 22

-Trunk disease
-Black Measles
-tiger-striped leaves

Question 23

How to minimize trunk diseases

Answer 23

Cane pruning is preferred
Anti-fungal paste can be painted on the wounds to keep spores from festering

Question 24

Black Rot

Answer 24

-Plagues vineyards in humid climates
-Spores are released with spring rains and attacks young green growth
-Forms small reddish-brown circular spots on leaves & dark lesions on the stems
-Copper based fungicides help

Question 25

Examples of fungal diseases

Answer 25

Powdery & Downy mildew
Sour Rot
Esca
Eutypa Dieback

Question 26

Examples of Bacterial diseases

Answer 26

-Pierce disease
-Grapevine yellows
-Crown gall

Question 27

Pierces Disease

Answer 27

-Infects the xylem of the vines and prevents transportation of water

Question 28

Symptoms of Pierces disease

Answer 28

Delayed budbreak, stunted growth, fruit dehydration, and drought symptoms; uneven shoot lignification and matchsticks

Question 29

Phytoplasmic diseases