Regent

Summary

Regent is Germany’s most successful red PIWI (Pilzwiderstandsfähig/fungus-resistant) variety, producing deeply colored, full-bodied wines comparable in quality to traditional Vitis vinifera varieties. Created in 1967 at the Geilweilerhof Institute in Germany, Regent offers excellent resistance to downy mildew, powdery mildew, and botrytis, enabling 60-80% reduction in fungicide applications while producing wines that rival Merlot in style. With approximately 2,000 hectares planted—making it Germany’s largest PIWI planting—Regent demonstrates that disease-resistant varieties can produce serious, age-worthy wines, not just everyday drinking wines.

Identity

VIVC: Entry #4572
Berry Color: NOIR
Type: PIWI (Interspecific hybrid)

Breeding Number: Gf. 67-198-3 (Geilweilerhof)

Creator: Gerhardt Alleweldt, Institut für Rebenzüchtung Geilweilerhof, Germany (1967)

Registration: Registered in Germany 1996; EU variety protection

Genetic Origin

Parentage: (Silvaner × Müller-Thurgau) × Chambourcin

Breaking down the parentage:

Silvaner: Traditional German Vitis vinifera
Müller-Thurgau: German crossing (Riesling × Madeleine Royale)
Chambourcin: French-American hybrid with strong disease resistance

Breeding Goals:

Strong fungal disease resistance
Deep color and quality tannins
Good wine quality comparable to vinifera
Reliable ripening in German climate

Result: Outstanding success; demonstrates PIWI can produce premium red wine.

Generation: First-generation PIWI (one hybrid parent)

Disease Resistance Profile

Disease	Resistance Level	Notes
Downy Mildew	HIGH	Strong resistance
Powdery Mildew	HIGH	Strong resistance
Botrytis	MEDIUM-HIGH	Good resistance
Black Rot	MEDIUM	Moderate resistance
Phomopsis	HIGH	Good resistance

Spray Reduction: 60-80% reduction vs. traditional varieties

Practical Impact:

2-3 treatments/season vs. 8-12 for traditional varieties
Organic certification much easier to achieve
Significant cost savings for producers

Distribution

Total Global Plantings: ~2,000 hectares

Country	Hectares	Status
Germany	~1,800	Largest PIWI planting
Switzerland	~100	Established
England	~30	Growing
Belgium	~20	Growing
Netherlands	~20	Growing
Poland	~15	Emerging
Other	~15	Various

German Distribution by Region:

Pfalz: ~600 ha
Rheinhessen: ~400 ha
Baden: ~300 ha
Württemberg: ~200 ha
Others: ~300 ha

Viticulture

Growth Characteristics

Vigor: Medium to high
Growth Habit: Semi-erect
Budbreak: Medium
Flowering: Mid-season
Véraison: Medium
Harvest: Medium (October in Germany)

Cluster and Berry

Cluster Size: Medium, conical
Cluster Density: Medium
Berry Size: Small to medium
Skin Thickness: Medium-thick (good color)
Skin Color: Blue-black

Climate Requirements

Ideal Climate: Cool to moderate continental
Heat Summation: 1,200-1,600 GDD (base 10°C)
Ripening: Reliable in German conditions
Frost: Moderate tolerance

Soil Preferences

Adaptable: Performs on various soils
Ideal: Well-drained, moderate fertility
German Sites: Performs on traditional wine soils

Viticultural Management

Training: VSP standard
Pruning: Spur or cane; moderate bud load
Yield Control: 60-80 hl/ha for quality
Spray Program: MINIMAL—key advantage
Canopy Management: Standard practices

The Sustainability Advantage

Regent’s disease resistance provides:

Dramatic reduction in chemical inputs
Lower carbon footprint (fewer tractor passes)
Reduced labor costs
Easier organic/biodynamic conversion
Better for biodiversity

Enology

Must Parameters at Harvest

Parameter	Typical Range	Notes
Brix	21-24°	Good accumulation
pH	3.3-3.6	Moderate
Titratable Acidity	5.5-7.0 g/L	Moderate
YAN	180-280 mg/L	Generally adequate

Phenolic Profile

Anthocyanins: HIGH (excellent color)
Total Tannins: Moderate to high
Color Stability: Very good
Quality: Compares favorably to vinifera

Aroma Compounds

Terpenes: Minor
C13-Norisoprenoids: Present (fruit character)
Character: Dark fruit, chocolate

Note: No “foxy” or hybrid off-flavors—a key achievement

Fermentation

Yeast Selection: Various; standard red wine yeasts
Temperature: 24-28°C
Duration: 10-14 days
Maceration: 10-21 days (style dependent)
Cap Management: Standard punch-downs/pump-overs

Wine Styles

Style	Method	Character
Fruity/Fresh	Short maceration, no oak	Cherry, approachable
Classic	Moderate maceration, some oak	Balanced, food-friendly
Premium	Extended maceration, barrique	Structured, age-worthy
Rosé	Direct press	Fresh, fruity

Malolactic Fermentation

Standard: Complete MLF
Effect: Softens wine; rounds tannins
Timing: Post-alcoholic fermentation

Oak Aging

Style	Oak Treatment	Duration
Fresh	None	N/A
Classic	Used oak	6-12 months
Premium	French barriques	12-18 months

Note: Regent responds well to oak; can produce serious, age-worthy wines

Aging Potential

Fresh Style: 2-4 years
Oak-Aged: 5-10 years
Premium: 10-15 years

Sensory Profile

Visual

Intensity: DEEP (excellent color)
Hue: Ruby-purple
Comparison: Rivals Merlot, Dornfelder

Aromatic Profile

Category	Descriptors
Fruit	Black cherry, blackberry, plum
Spice	Subtle pepper, clove
Other	CHOCOLATE, coffee (especially with oak)
Herbal	Subtle herbs
Aged	Leather, tobacco

Palate

Body: Medium to full
Acidity: Medium
Tannins: SOFT, approachable
Alcohol: Moderate (12-13.5%)
Finish: Medium to long

Comparison to Vinifera

Regent is frequently compared to:

Merlot: Similar body, soft tannins, dark fruit
Dornfelder: Similar color intensity, German heritage
Pinot Noir: Less complex but approachable

Winemaker Considerations

Challenges

Perception: PIWI varieties still face prejudice
Marketing: Explaining hybrid heritage
Price Positioning: Balancing sustainability value
Vigor Control: Can be vigorous
Regional Focus: Limited international recognition

Opportunities

Sustainability Leader: Demonstrates PIWI potential
Quality Proof: Rivals vinifera quality
Cost Efficiency: Lower production costs
Market Differentiation: Sustainability story
Climate Adaptation: Reliable ripening

Winemaking Tips

Standard red winemaking techniques apply
Oak aging enhances complexity
Soft tannins allow early drinking
Deep color is natural—don’t over-extract
Market on sustainability credentials

Permitted Appellations

Germany

Status: Qualitätswein in all 13 Anbaugebiete
Classification: Can be used for Prädikatswein
VDP: Some estates now include in classification

Other Countries

Switzerland: Various AOC wines
England: English Wine PDO
Belgium: Belgian wine appellation
Netherlands: Dutch wine designation

The PIWI Success Story

Regent represents a turning point for PIWI varieties:

Historical Context

1960s-1990s: Hybrid varieties stigmatized
Traditional belief: Only vinifera produces quality wine
Regent challenge: Prove hybrids can compete

Regent’s Achievement

Quality comparable to vinifera
No hybrid off-flavors
Deep color, good structure
Age-worthy wines possible
Accepted for German Qualitätswein

Industry Impact

Changed perception of PIWI varieties
Opened door for other PIWI in premium segments
Demonstrated sustainability without quality sacrifice

Comparison with Other PIWI Reds

Characteristic	Regent	Cabernet Cortis	Pinotin
Color	Deep	Very Deep	Medium
Body	Medium-Full	Full	Light-Medium
Tannins	Soft	Firm	Soft
Downy Resistance	High	High	Very High
Character	Merlot-like	Cabernet-like	Pinot-like

Sustainability Impact

Regent exemplifies PIWI benefits for sustainable viticulture:

Environmental

60-80% fewer fungicide applications
Reduced water/soil contamination
Lower carbon footprint
Better biodiversity

Economic

Lower production costs
Easier organic certification
Reduced labor
Higher margins possible

Safer working conditions
Reduced chemical exposure
Consumer demand for sustainability

Sources

Robinson, J., Harding, J., & Vouillamoz, J. (2012). Wine Grapes. Ecco/HarperCollins. Publisher Link
VIVC Database - Vitis International Variety Catalogue
Julius Kühn-Institut (German Federal Research Centre)
PIWI International Association
Deutsches Weininstitut (German Wine Institute)
Alleweldt, G. (1995). Breeding of disease-resistant varieties. Vitis 34(2). Vitis Journal

Last Updated: January 13, 2026