Final answer:
The primary red grape in the Eastern/Upper Loire is Pineau d'Aunis, and the dominant white grape is Sauvignon Blanc. These varieties are well-suited to the region's cooler and wetter climate, contributing to the Loire Valley's reputation for fine wine production.
Step-by-step explanation:
The primary red grape of the Eastern/Upper Loire in France is the Pineau d'Aunis, also known as Chenin Noir. As for the white grape, the Eastern/Upper Loire is renowned for its Sauvignon Blanc, which is the dominant white grape in the region.
These grapes thrive in the Loire Valley due to its favorable climate and rich terroir, which is characterized by a cooler, wetter climate in the central portion of France, providing optimal conditions for these grape varieties.
France's diverse climates and geographical areas greatly contribute to the cultivation of different types of grapes suited for wine production.
This diversity in viticulture is also observed in other countries that have a tradition and culture of wine-making, such as Italy in Europe and more recently, Brazil, where the Miolo Vineyard in the south region, with its wealth of Italian immigrants, is known for wine production.