A NEW SOLANUM SATELLITE DNA CONTAINING SPECIES-SPECIFIC SEQUENCES WHICH CAN BE USED FOR IDENTIFICATION OF GENOME PARTS IN SOMATIC HYBRIDS OF POTATO

Complete 337-bp repeats of a satellite DNA component of Solanum demiss um were cloned after PCR amplification and subsequently sequenced (pSD B6). This satellite was firstly detected by hybridization of Solanum D NA with a short clone pSDT382, which was previously cloned from S. dem issum and described to be species-specific for some Solanum wild speci es and also for some breeding lines of potato. Within the sequence of pSDB6 high similarity of 77% was detected to a 75-bp region of a commo n Solanum-specific repeat (pSA287; 183 bp in length). Obviously, the s pecies-specificity is restricted to a short region within the 337-bp e lement. This new element appears to be present in S. okadae, S. kurtzi anum, S. maglia, S. acaule and S. demissum (belonging to different ser ies of potato) and could be also detected by Southern blot in some S. tuberosum breeding lines. Therefore, the short clone pSDT382 can be us ed to detect specific genome parts of species such as S. okadae, S. ku rtzianum and S. maglia in symmetric somatic hybrids obtained by protop last fusion with selected S. tuberosum breeding lines not containing t his repeat type. Evolution of satellite DNA within Solanum/Lycopersico n species is discussed. (C) 1997 Elsevier Science Ireland Ltd.