Wine Production Flashcards

What is weather?

Answer: Changes over a period of time (Day to day, hour to hour)

Weather refers to the atmospheric conditions at a specific place and time, encompassing short-term variations in temperature, precipitation, wind, and humidity. It describes the immediate state of the atmosphere, changing frequently from day to day or even hour to hour.

What is climate?

Answer: Represents the average weather over a long period of time

Climate is distinct from weather as it describes the long-term average weather patterns for a particular region, typically calculated over 30 years or more. It encompasses the general trends and expected conditions, rather than day-to-day fluctuations.

What are anticyclones?

Answer: Areas of high pressure; sinking; in the N hemisphere air rotates clockwise

Anticyclones are characterized by areas of high atmospheric pressure where air is sinking. In the Northern Hemisphere, the Coriolis effect causes the air within an anticyclone to rotate clockwise, typically bringing stable, clear, and dry weather conditions.

What is the role of sunlight?

Answer: To activate and maintain the photosynthesis process

Sunlight is fundamental for grapevines as it provides the energy necessary for photosynthesis, the process by which plants convert light energy into chemical energy. This process is crucial for the vine's growth, development, and the ripening of grapes, influencing sugar accumulation and flavor development.

How can you decrease solar radiation and thus berry temperature?

Answer: Shade the berries with leaves

Shading the berries with leaves is a common viticultural practice to mitigate excessive solar radiation and reduce berry temperature. This helps prevent sunburn, maintain acidity, and promote a more balanced ripening process, especially in hot climates, by protecting the fruit from direct sun exposure.

True or False: Sunlight has an inhibitory effect on the development of diseases.

Answer: TRUE

Sunlight, particularly its UV component, has an inhibitory effect on the development of many fungal and bacterial diseases in grapevines. Increased light exposure can dry out foliage and fruit surfaces, creating an less favorable environment for pathogen growth and reducing disease pressure.

Winter temperatures below ___________ cause severe injuries, ranging from damaged winter buds to grapevine mortality.

Answer: -15 to -20 ˚C

Grapevines are susceptible to severe injury or even mortality when winter temperatures drop below -15 to -20 ˚C. These extreme cold temperatures can damage dormant buds, vascular tissues, and roots, significantly impacting the vine's health and future productivity.

In spring, at onset of vegetative growth, the vine is sensitive to temperatures below ____________.

Answer: 0 ˚C, especially <-2.5˚C

In spring, once vegetative growth has begun, grapevines become highly sensitive to frost, particularly at temperatures below 0 ˚C, and especially damaging below -2.5 ˚C. Young shoots and developing buds are tender and can be easily killed by freezing temperatures, leading to significant yield losses.

At what temperature do grapes become affected by extreme heat?

Answer: > 35 ˚C

Grapes can be adversely affected by extreme heat, typically when temperatures exceed 35 ˚C. Prolonged exposure to such high temperatures can lead to sunburn, desiccation, loss of acidity, and an imbalance in sugar and phenolic ripeness, negatively impacting wine quality.

What are the effects of spring frost?

Answer: Can cause mortality of primary buds or young shoots, delays vegetative growth, reduces yield, and affects current year and next year

Spring frost is highly detrimental to grapevines, as it can kill newly emerged primary buds and young shoots. This damage delays vegetative growth, significantly reduces the current year's yield, and can even impact the following year's crop by forcing the vine to rely on less fruitful secondary buds.

What is the role of sunlight?

Answer: All of the above

Sunlight plays a multifaceted and essential role in viticulture. It activates and maintains photosynthesis, which is the core process for vine growth and fruit development. Furthermore, sunlight is a central element in various light-activated processes within the plant and significantly influences vine growth and fruit ripening through its thermal effects, contributing to sugar accumulation and flavor development.