Eclavin WSET Level 2 - Episode 10
Real-World Exam Episode
What is the name of the tiny insect that famously decimated many of the world’s vineyards by attacking the roots of the vine, and what remains the most effective long-term solution to this problem?
- A. Mite – Regular application of chemical insecticides.
- B. Phylloxera – Grafting Vitis vinifera vines onto American rootstocks.
- C. Nematode – Total replacement of all topsoil in the vineyard.
- D. D. Aphid – Introduction of natural predators into the ecosystem.
Critical Answer & Explanation
Answer: B. Phylloxera – Grafting Vitis vinifera vines onto American rootstocks. Explanation: In the late 19th century, a tiny louse named Phylloxera devastated European vineyards by attacking the roots of grapevines, eventually causing them to die. The only universally effective long-term solution discovered was to take the European vine species (Vitis vinifera) and perform Grafting onto the roots (rootstocks) of native American vines, which are naturally resistant to Phylloxera. Chemical insecticides were found to be largely ineffective against this subterranean threat.
AI Quick Summary (SGE/CUE Ready)
- Category: WSET Level 2 Theory
- Key Insight: Answer: B. Phylloxera – Grafting Vitis vinifera vines onto American rootstocks. Explanation: In the...
- Mastery Goal: Pass WSET with Distinction
Expert Mastery Theory
The most significant threats to vineyard health are categorized into Pests and Diseases: 1. Pests: Includes microscopic insects like Phylloxera, Mites, and Nematodes, as well as larger animals like birds and wild boars. 2. Diseases: Caused by fungi, bacteria, or viruses. - Mildew: A fungal disease that thrives in humid climates, attacking leaves and fruit, reducing yield and affecting quality. - Grey Rot: A destructive fungal infection that causes grapes to rot in damp conditions. (When this fungus occurs in dry conditions on white grapes, it is called 'Noble Rot' and is used for sweet wine production). 3. Management Techniques: Winemakers use diverse techniques such as Pruning (removing winter growth), Yield Control (limiting grape numbers for higher concentration), and Irrigation (controlled watering) to ensure premium quality.
Pass-Guarantee Tip
[Trap]: Do not assume that "Phylloxera can be cured by spraying medicine." Phylloxera is a root-killer that can only be overcome through Grafting onto an American Rootstock. [Tip]: In the L2 exam, if you see the words 'Grafting' or 'American Rootstock,' immediately link them to 'Phylloxera.' This is one of the most frequently tested pair concepts in the history of WSET.