The World of Apples

Apple varieties, Germany

Weirouge

An acid, astringent red-fleshed apple for processing; Germany's fruit genebank files it as Michurin's Roter Mond

History

Weirouge is an apple that is red outside and in3,4. In 2006 Sadilova and colleagues called it the most intensely coloured German cultivar, and wrote that it had been bred at Weihenstephan, mainly for processing, and officially registered in 19971; a 2018 review repeats the place and the date6. Peter Stoppel applied for a Community plant variety right in June 1999; after examination by Germany’s Federal Plant Variety Office it was granted in May 2004, and it ended on 16 May 20112. The fruit that Sadilova’s team analysed came from Stoppel at Kressbronn1.

Accounts of its origin differ. A 2010 report in Good Fruit Grower called it a chance seedling found in Germany4. The German Fruit Genebank lists Weirouge as another name for Roter Mond, a variety it credits to the Russian breeder I. V. Michurin, crossed in 1915 from parents it does not know3.

Weirouge has since become a parent of newer apples. The apple sold under the trade mark Baya Marisa, registered as Bay 3484, was bred from it6,7, and in 2020 microsatellite fingerprints confirmed Weirouge as a parent of five Swiss apples, among them Luresweet and Lurefresh7.

The fruit

The German Fruit Genebank describes a medium-sized apple flushed red all over, with no ground colour showing, red-marbled flesh and red pips; it is picked in September and eaten in September and October3. In the same report Walter Guerra, of the Laimburg research centre in South Tyrol, described it as red from flower to leaf to flesh, and after several years of trials in South Tyrol found the fruit astringent, mealy, prone to scald and lacking good flavour4.

Sadilova and colleagues measured 1,271 mg of malic acid in 100 g of edible fruit, against 270–790 mg reported for apples generally, and a sugar–acid ratio of 7.1, which makes it a fairly acid apple1. Its red pigments, the anthocyanins, came to 10.8 mg per 100 g of whole fruit, 8.1 mg per 100 g of flesh and 20.6 mg per 100 g of peel, where red-skinned apples hold 0.2–0.8 mg1. They tentatively identified two anthocyanins not found in apples before, and put the brightness and stability of the colour down to the fruit’s high acidity rather than to any particular pigment1.

Growing

The genebank records strong scab on the leaves and very strong scab on the fruit, but little mildew, and rates the tree as frost-resistant3. Weirouge is diploid7.

Uses

Sadilova’s team understood it to have been bred mainly for processing1, Guerra saw potential only for processing4, and the genebank classes it as a culinary apple3. In the Vinschgau the grower Karl Luggin made juice, apple wine and dried fruit from it4. Flachowsky and colleagues at the Julius Kühn-Institut cite Weirouge as typical of most red-fleshed varieties, whose taste is not good enough to market them, and note that a bitter taste is inherited along with the red flesh5.

Where the sources disagree

  • Origin. Bred at Weihenstephan1,6; a chance seedling found in Germany4; or the same variety as Roter Mond, from a cross made in Russia in 19153. The genebank’s record does not say how the two names were matched.
  • Type of red flesh. Wang and colleagues class Weirouge as type 2, in which only the flesh is red6. Guerra described it as red in flower, leaf and flesh4, and the genebank records red blossom3: the signs of type 1, in which red flesh comes with red leaves5,6.

Family tree

Offspring in the atlas

Sources

  1. Chemical quality parameters and anthocyanin pattern of red-fleshed Weirouge apples, E. Sadilova, F. C. Stintzing and R. Carle, Journal of Applied Botany and Food Quality 80: 82–87, 2006. Supports: Weirouge "the most intensely coloured German cultivar", "bred in Weihenstephan (Germany) primarily for processing purposes and officially registered 1997"; the fruit studied, of 2005, from Stoppel, Kressbronn; Table 1: malic acid 1271 mg per 100 g against 270–790 in the literature for apples, a sugar–acid ratio of 7.1, "a fairly acidic apple variety"; Table 2: anthocyanins 10.8 mg per 100 g in the whole fruit, 8.1 in the flesh and 20.6 in the peel, against 0.2–0.8 mg in red-peeled apples; two anthocyanins not previously found in apples tentatively identified; the colour's brilliance and stability ascribed to the high acidity of the fruit, not to a particular pigment pattern.
  2. Community plant variety rights register, public search: Weirouge, Community Plant Variety Office (CPVO). Supports: denomination Weirouge (Malus domestica); application 19990817 of 7 June 1999, applicant Peter Stoppel; examination office the Bundessortenamt (Germany); grant 13320 of 17 May 2004; status terminated, expiry date 16/05/2011.
  3. Passport data: Roter Mond (in German), Deutsche Genbank Obst (German Fruit Genebank). Supports: Roter Mond with the synonym Weirouge; breeder "Mitschurin, I.W.", year of the cross 1915, country of origin the Russian Federation, mother and father unknown; fruit medium-sized, ground colour not visible, over colour a flat red, flesh red-marbled, pips red; picked in September, ripe to eat in September and October; a culinary apple (Wirtschaftsapfel); frost-resistant; red blossom; scab on the leaves strong and on the fruit very strong, mildew on the leaves weak.
  4. Totally red, Geraldine Warner, Good Fruit Grower, October 2010, pp. 20–21 (copy on the Lubera website), 2010-10. Supports: Weirouge "a chance seedling found in Germany", grown commercially in Europe but, according to Walter Guerra of the Laimburg Research Center for Agriculture and Forestry in South Tyrol, not suitable for fresh consumption; "fully red from the flowers to the leaves to the flesh"; tested in South Tyrol for several years, with potential only for processing; astringent, mealy, susceptible to scald and lacking good flavour; Karl Luggin, a grower in the Vinschgau Valley, making juice, apple wine and dried fruit from it.
  5. The impact of Mendelian genetics on the breeding of apple and sweet cherry (in German), H. Flachowsky, O. F. Emeriewen, M. Schuster, A. Peil, J. Lempe and T. Wöhner, Julius Kühn-Institut; Journal für Kulturpflanzen 74 (11–12): 242–256, 2022. Supports: most red-fleshed varieties, Weirouge for example, insufficient in taste for marketing, a bitter note being inherited with the red flesh; in type 1 red-fleshed apples a sixfold repeat (R6) of a sequence motif in the regulatory region of the MdMYB10 gene gives red flesh and red leaves, inherited in Mendelian fashion.
  6. Malus sieversii: the origin, flavonoid synthesis mechanism, and breeding of red-skinned and red-fleshed apples, Nan Wang and others, Horticulture Research 5: 70, 2018-10-15. Supports: "In Germany, the Type 2 red-fleshed apple Weirouge was bred in Weihenstephan and first registered in 1997"; Baya Marisa "then bred using Weirouge as a parent"; type 1 red-fleshed apples red in the flesh, skin, leaves and other vegetative tissues, type 2 red only in the flesh.
  7. Molecular genetic identification of apple cultivars based on microsatellite DNA analysis. I. The database of 600 validated profiles, S. Baric, A. Storti, M. Hofer, W. Guerra and J. Dalla Via, Erwerbs-Obstbau 62: 117–154, 2020. Supports: Table 2: Weirouge diploid (2n), Germany, 1999, its profile from accessions in the Bundessortenamt and Laimburg collections; BAY 3484 listed with the trade mark name Baya Marisa; Weirouge confirmed by the study's own SSR data (C) as a parent of LUB A11706, Lurefresh, Luregust, Lureprec and Luresweet, all from Switzerland.

All 95 varieties from Germany