Variety references

The descriptive, crop and use characteristics included in the illustrated files are from the official documents published by GEVES for the varieties registered in France.

Several criteria

The varieties are characterized by 21 criteria rated either by a value from 1 to 9, or by a symbol.

The crop and use criteria are evaluated against reference control varieties, within the framework of a network of local trials and during 2 years.

You can find the details of these criteria in each of the 7 groups that gather them.

Early tuberization

Scores range from 5 (= BINTJE) to 9 (= SIRTEMA). Mid-range scores reflect earlier tuberization than BINTJE, but later tuberization than SIRTEMA.

Early ripening or maturity

Rate	Maturity	Examples
9	Very early	Belle de Fontenay
8	Early	Sirtema
7	Semi-early	Bintje, Charlotte
6	Semi-early to medium	Temptation, Nazca
5	Medium	Magnum
4	Semi-late	Cephora
3	Semi-late to late	Kelly
2	Late	Hinga, Makhai
1	Very late	Eris

Tuber characteristics

Peel

The tuber peel color can be different depending on the variety:

white (Bl),
light yellow (Jc),
red (R),
bicolored (Bic) = yellow skin, red or purple buds.

Flesh

The color can be:

white (Bl),
yellowish white(Blj),
light yellow (Jp),
yellow (J),
dark yellow (Jf).

Shape

It is defined by the tuber’s “Length/Width” ratio, measured on samples of 50-60 mm tubers.

Length/Width
Less than 1.09	rounded (R)
Between 1.10 and 1.39	short to oblong (Oc to O)
Between 1.40 and 1.69	oblong to elongated (O to Oa)
Between 1.70 and 1.99	oblong to elongated (Oa to All)
Greater than 1.99	elongated (All) or long

The ratio “Length/Width” can greatly change depending on the year, especially from climatic conditions, the location, and the crop growing period. Therefore, it is important to compare the varieties with the following reference controls (see table on the right).

The shape is considered for long and very long varieties: claviform (Clav), reniform (Ren), piriform.

The term variable (Var) is used when a significant spread for the tuber “Length/Width” trait exists in the same sample.

Round shape	type Kaptah Vandel, LD17
Short oblong shape	type Sirtema
Oblong shape	type Bintje, Maïwen
Long oblong shape	type Charlotte
Long shape	type B.F 15, Roseval, Amandine

Eye depth

Note	Eye depth	Exemples
9	Very shallow	BEA
7	Shallow	BINTJE, Charlotte
5	Slightly sunken	Saturna
3	Half-sunken	Kaptah Vandel
1	Sunken

Regularity of shape

Note	Regularity of shape	Exemples
9	Very regular	Bea
7	Regular	Bintje, Amandine
5	Fairly regular	Exquisa,
3	Not very regular	Ackersegen
1	Irregular

Tuber size

Rate	Share of large tubers	Examples
9	Very high	Magnum, Universa
8	High to very high	Synergy
7	High	SIRTEMA, Desirée, Monalisa
6	Quite high	BINTJE
5	Medium	Amandine, Charlotte
4	Quite low	B.F 15, Tentation
3	Low
2	Low to very low
1	Very low

Vegetative rest

The vegetative rest is the time, after harvest, during which a tuber, even placed in environmental conditions favorable to germination (temperature between 15 and 20°C; hygrometry higher than 90%), is unable to germinate.

Rest time	Examples
Very short	Sirtema, Starlette
Short	Agata
Quite short	Charlotte, Francine, Amandine
Medium	Bintje, Gourmandine
Quite long	Monalisa, Allians
Long	Tentation
Very long	Désirée

Use characteristics

The varieties are divided into groups A, B, C and D, and in some cases into intermediate groups A-B, B-C or C-D, mainly based on how much they crumble when cooked, how firm their flesh is and how floury they are.

Group A: Potatoes with fine flesh, little or not floury, watery to moderately watery, no crumbling when cooked.
Group B: Potatoes with fairly fine flesh, a little floury, light crumbling when cooked
Group C: Potatoes with floury flesh, dry, coarse and with a fairly strong crumbling when cooked
Group D: Potatoes with very floury flesh, dry, heavy crumbling when cooked.

The firm-fleshed varieties for consumption belong mainly to group A and sometimes to group A-B. The varieties for consumption belong mainly to group A-B and B, more rarely to groups B-C or C. The starch varieties are almost exclusively in group D.

The dry matter content of consumer varieties was measured by the densimetric method on 5 kg samples taken from a number of comparative trials. This characteristic can greatly vary depending on environmental conditions and production techniques, but the varieties’ classification is usually not affected. The dry matter content of the tubers partly influences the culinary and technical characteristics of the varieties.

Blackening after cooking (flesh “graying”) mainly appears when tubers are boiled or steamed, peeled or cut and left exposed to the air. Varietal sensitivity is primarily determined in comparison to the ACKERSEGEN and CLAUSTAR controls (quite high) and the BINTJE control (none).

Friability is mainly assessed based on its suitability for processing into chips. Varieties with the best frying suitability have this information listed on their card. For others, friability ranges between medium and strong.

The shelf life is rated from 1 to 9 (BINTJE is rated 5). A high score means that the variety has a good to very good storage capacity, i.e. late germination, low sprout production and limited shrinkage. This characteristic is interesting for mid-season varieties, especially if they cannot be stored in ventilated or refrigerated stores. However, in general, varieties with a score below 4 are often more difficult to store on the long term.

Sensitivity to diseases, pests and physiological accidents

Sensitivity is based on comparison to a range of control varieties with different sensitivity levels.

1	Very susceptible
2	Susceptible to very susceptible
3	Susceptible
4	Susceptible to moderately susceptible
5	Moderately susceptible
6	Moderately to slightly susceptible
7	Slightly susceptible
8	Slightly to very slightly susceptible
9	Very slightly susceptible

For wart disease, the rating 9 is given to varieties not attacked in infection tests. The ratings 3, 2 and 1 are given to varieties responding with medium to large galls (type BINTJE). Note: from the varieties registered since 2002, the test for wart disease sensitivity is no longer performed. No indication means that the variety has not been tested.

For virus A and some strains of virus X, varieties with hypersensitivity that provide them with field resistance are rated as resistant (R in the tables).

For the potato cyst nematode (Globodera rostochiensis), R and ® mean resistant and highly insensitive to the RO1-4 pathotype.

The sensitivity test to Globodera pallida, pathotype PA2-3, has only been performed since 1994. To date, only the varieties ILEDHER and STRONGA are described as resistant. STRONGA has a dual resistance to G. rostochiensis and G. pallida.

Sensitivity to potato late blight is a characteristic that is likely to evolve, especially in varieties with single-gene resistance of type R, by the emergence of pest species that can overcome this resistance. The ratings given to some old and widely grown varieties are probably overestimated.

Sensitivity to sprouting (= sensitivity to incubation / speed of incubation) is rated, like the diseases, on a scale from 1 (= very sensitive) to 9 (very little sensitive). A strong sensitivity to sprouting is specific to certain varieties, described in practice as delicate. These require more care than others to preserve and prepare their seedlings, as well as to work the soil before planting.

Yield

The yield is measured in comparison with reference controls chosen, for each maturity class and for each variety category, among the most widely grown or most representative varieties. The yield is then assessed in the following way:

Varieties registered before 1995

For early, semi-early, medium and semi-late varieties, the yield is compared to the reference control BINTJE (index = 100); for late varieties, to the KERPONDY (index = 100) control.
For starch varieties, the index 100 for starch yield is the KAPTAH VANDEL control. The starch yield was calculated by multiplying the tuber yield by the average starch content determined by the starchometer (densimetric method) in the same experiments.

Varieties registered since 1995

In the illustrated files, the yield is expressed as a percentage of the official control for the two years of CTPS experiments prior to the registration year (example: 107% of (SIRTEMA+ OSTARA)/2 – Years 1999 and 2000 for an early to medium-early consumption variety registered in 2001).

In the summary tables, the index, in relation to the controls BINTJE and KAPTAH VANDEL, is a value estimated by ARVALIS Institut du Végétal.