Viti n Vini - Brainscape Flashcards
Phomopsis viticola is a simlar (but separate fungus) disease to what?
Eutypa Dieback
What is Esca commonly known as? What is unique about this fungus?
- Black Measles
- This is a result of a complex of fungi, rather than a single organism
What is Bordeaux Mixture? When was it developed?
- CuSO4 + H2O + Lime
- 1885
Symptomatically, what diseases are like viruses?
Phytoplasma
What bacterium causes Bacterial Blight?
Xanthomonas ampelina
Where does Esca thrive? What are the treatments available? How is it spread?
- Warm climates, but it exists worldwide
- No known control or cure
- Rain, wind, or pruning shears
What fungul diseases affect vineyards?
- Powdery Mildew
- Downy Mildew
- Eutypa Dieback
- Esca
- Black rot
- Bunch rot
In what order do these occur: harvest, fruit set, budbreak, veraison, flowering?
Budbreak, flowering, fruit set, veraison, harvest
What is a VSP trellising system?
Vertical Shoot Positioning - may be used for either cane- or spur-pruned vines
What is soutirage?
Racking
What are the symptom of Black knot?
(Crown gall)
Vines develop tumors (galls) on its trunk, which girdle or strangle the vine, withering or killin the portion of the vine above
What is a chapeau?
Cap
What virus diseases are affecting vineyards?
Leafroll & Fanleaf Degeneration
What is pigeage?
Punching down
What low temperature will not allow yeast to work? What high temperature kills most yeast?
- 50ºF
- 113ºF
What bacterial diseases affect vineyards?
- Pierce’s Disease
- Crown gall
- Bacterial Blight
What are MOG and “jacks”?
- MOG = Material Other than Grapes
- Jacks = stem pieces left in grapes
What is first visiable as “oil” spots on leaves and later results as what?
- Downy Mildew
- As spores germinate, a white cottony growth develops on the underside of leaves
Vines prefer what temperature range? What is the ideal temperature?
Prefer - 50-68ºF
Ideal - 57ºF
What remontage?
Pump over
What negative effect does Peronospera have on the vines?
(Downy Mildew)
- It attacks the green portion of the vine, causing the leaves to drop off the vine - limiting it’s ability to photosynthesive
- The fungus survive the winter on fallen leaves in the soil - the spores reach the vine again w/ the help of rain splatter in the spring
What temperature can red wine fermentations reach? What temperature causes risk? What the risks?
- Red wine ferm.= 90+ºF
- Risk = 95ºF - may cause volatized flavors or stuck fermentations
Where is the Tendone trellising system commonly used? What is it called there?
- Italy - Pergola
- Portugal - Enfrocado
What disease is responsible for as much as 60% of the world’s grape production losses?
Leafroll virus
What are the four broad categories of vine disease?
- Fungal
- Viral
- Bacterial
- Phytoplasma
What does “san soufre” indicate?
“Without sulfur”
How long does flowering occur? What is occuring during flowering?
- 10 days
- Self-polinating - begins the process of fertilization
What are the vulnerabilities during flowering?
Cold, frost, and wind
What temperatures do red and white grapes prefer to ripen successfully?
Red ≈ 70ºF
White ≈ 66ºF
What is délestage?
The wine is racked into a separate vessel, emptying the one with the cap, and then pumped back over the cap
What are the symptoms of Pierce’s Disease? What treatments are available?
Symptoms
- A scourge, rendering vines incapable of producing chlorophyll
- Kills vines in 1-5 years
No treatments or chemical controls
Viticulture is restricted to what temperate bands of latitudes?
30º-50ºF
What trellising system is preferred for Pinot Noir in Champagne?
Cordon de Royat
How long is traditional Nebbiolo post-ferment macerated?
at least a month
What is the species of American white oak? Traditionally is it split or sawn? Kiln or air dried?
- Quercus alba
- Sawn - it is less porous, no fear of leakage
- Kiln dried - although many American coopers are using air-drying techniques
What are the ranges for the California Heat Summation Index?
- Region I: 2,500°days F (>1,371°days C)
- Region II: 2,500-3,000°days F (1,372-1,649°days C)
- Region III: 3,000-3,500°days F (1,650-1,927°days C)
- Region IV: 3,500-4,000°days F (1,928-2,204°days C)
- Region V: <2,205°days C)
When does budbreak generally occur in the North and South hemispheres? What average temp is required? What is the vulnerability?
- North - March/April
- South - Sept/Oct
- As the mean air temp surpasses 50ºF
- Vulnerability - frost
What is a “nepovirus”? Which nepovirus is a concern today?
- A nepovirus is a virus spread by soil nematodes feeding on infected roots
- Fanleaf Degeneration
When do the vines start bleeding water sap from the pruned canes?
February (N Hemi) or August (S Hemi)
What is collage?
Fining
What are the symptoms of Bacterial Blight? What are the treatments?
Symptoms -Often kills young vines -Shoots develop dark bronw streaks early spring -Eventually wither & die Treatments -Hot water treatments -Copper sprays, like Bordeaux mixture
What are anthocyannins?
Color compounds
Why are off-dry and sweet whites often filtered?
The sugar can lead to unexpected refermentation in the bottle
When does flowering occur?
6-13 weeks after initial budbreak (Depends on the climate)
What is acetic acid?
- Acetic acid reacts with ethyl acetate (a culprit of VA)
- A small amount is converted from acetaldehydes
- Excessive amounts can be produced by acetobacter (the group of bacteria responsible for turning wine into vinegar in the presence of oxygen)
What are the 3 stages of barrel making?
- Chauffage (warming)
- Cintrage (shaping)
- Bousinage (toasting)
T o F - A grape cluster is the effect of a single fertilization during flowering.
False - each grape is the product of individual fertilization