Viticulture Flashcards
(123 cards)
How can spider mites be managed?
- sprinklers or cover crops to reduce dust
- predatory mites
- pesticides
What is the optimal temperature for germination?
79 - 90 degrees F
How is leafroll virus spread?
Unclean grafting and mealybugs
What is the optimal temperature range for photosynthesis?
64 - 91 degrees F
What causes downy mildew (peronospersa)?
- water mold living in vine tissue
- warm springs and rainy, warm summers
What is the optimal temperature for vine flowering?
63 degrees F
Describe Esca?
- complex fungal disease caused by a group of organisms
- favors warm, dry climates
- enters through pruning wounds
- tiger striping on leaves
- reduces yield, kills in a few years
What are the symptoms of Pierce’s Disease?
- bacteria clogs sap channels
- shrivels grapes
- drops leaves
- kills between 1 to 5 years
What are the symptoms of grapevine yellows?
- delayed budburst
- droopy shoots
- failure of shoots to lignify
- leaves turn yellow or red
How is Fanleaf virus transmitted?
nematodes
How is Pierce’s disease spread?
Glassy winged sharpshooter
How does Eutypa dieback attack a vine?
through pruning wounds
How is oidium best managed?
- keep open canopy
- sulfur treatments
What are the visual symptoms of downy mildew?
- oil spots and white downy growth on leaves
- defoliation
What are the symptoms if powdery mildew?
- dull grey or black patches on leaves
- reduces yield
How are grapevine yellows spread
insects
How is Pierce’s Disease managed?
- no cure but insecticides may help
- remove vine from insect habitats
- predatory wasps
- quarantine exposed plants
How is leafroll virus managed?
- no cure, remove vine
- screen for virus in nurseries
- reduce mealybug populations via open canopies and predatory insects
Leafroll and Fanleaf are what type of diseases?
viral
What are the visual symptoms of phylloexera?
- insect eggs on vine roots
- pale galls on leaves
- stunted growth
- yellow leaves
- vine death
How is downy mildew managed?
- open canopy
- good drainage
- Bordeaux mixture (copper sulfate and lime)
What is the most common grapevine yellow disease?
Flavescence doree
What are the symptoms of fanleaf virus?
- stunted growth
- distorted canes
- pale, deformed leaves
What are 2 synonyms for gobelet training?
- albarello
- en vaso
- bush training