Molecular analysis of highly repeated genome fractions in Solanum and their use as marker for the characterization of species and cultivars

• Published in: Theoretical and applied genetics Vol. 85; no. 6-7
• Main Authors: Schweizer, G. (Bayerische Landesanstalt fuer Bodenkultur und Pflanzenbau, Freising (Germany). PZ 1.3 'Biotechnologie'), Borisjuk, N, Borisjuk, L, Stadler, M, Stelzer, T, Schilde, L, Hemleben, V
• Format: Journal Article
• Language: English
• Published: 1993
• Subjects: ADN; ENZIMA DE RESTRICCION; ENZYME DE RESTRICTION; ESPECE; ESPECIES; MARCADORES GENETICOS; MARQUEUR GENETIQUE; Repeated DNA; Restriction satellite; RFLP; Solanaceae; SOLANUM; Species-specificity; VARIEDADES; VARIETE
• ISSN: 0040-5752; 1432-2242

Highly repeated DNA of potato (Solanum sp.) was characterized by cloning various major repeated elements of the nuclear genome. The percentage of the nuclear genome of the specific fractions and the restriction enzyme patterns were determined in order to show the distribution and organization of the respective repeats in the genome of Solanum tuberosum cultivars, dihaploid breeding lines and in wild species of Solanum. Several of the clones obtained were represented in a high copy number but showed no informative RFLP patterns. More information was gained from 'restriction satellite' repeats. The clone pR1T320 was found to contain satellite repeats (360 bp in length) that are proportionally present in the genome of all Solanum species at frequencies, between 0.5% and 2.6% and which are differently organized. This repeat was also found in the genera Lycopersicon, Datura and Nicotiana. With various restriction enzymes characteristic RFLP patterns were detected. A more or less genus-specific element for Solanum was the 183-bp repeat (clone pSA287; between 0.2-0.4% of the nuclear genome) that was present in the majority of the Solanum species analyzed except Solanum kurtzianum, Solanum bulbocastanum and Solanum pinnatisectum. In a few wild species (prominently in Solanum kurtzianum, Solanum demissum and Solanum acaule) a specific repeat type was detected (clone pSDT382); repeat length approximately 370 bp) that could be used to trace the wild species introduced into S.tuberosum cultivars. The repeats analyzed together with the 18S, 5.8S and 25S ribosomal DNA (1.9-5.2%, corresponding to 1800-5500 rDNA copies) comprised approximately 4-7% of the Solanum genome.