Microsatellite Development for Sunflower

PANIEGO, NORMA; MUÑOZ, MARIANNE; ECHAIDE, MERCEDES; FERNÁNDEZ, LUIS; FACCIO, PAULA; ZANDOMENI, RUBÉN; SUÁREZ, ENRIQUE Y.; HOPP, H. ESTEBAN

San Diego

Conferencia; VII International Plant and Animal Genome Conference; 1999

Sunflower (Helianthus annuus) and Lettuce can be considered the model plant systems for the genomic study of the Compositae and are important agronomic crops. INTA and a consortium of seed companies* have joined efforts in the development of microsatellites for the genomic analysis of this important oilseed crop in Argentina. In this stage, we were carried on with isolation of new microsatellite markers by screening a non-enriched sunflower genomic library cloned in Lambda phage. In this sense, hybridization screened have been performed using approximatively 20 bp oligonucleotides containing different arrays. Up to now, 788 microsatellites positive clones were isolated using the following motifs (AG)n, (GT)n, (ATC)n, (ATT)n, (CGG)m, (TTG)n, (TGG)n, (TCT)n, (GAG)n, (CAG)n, (CATA)n, (GATA)n and (GGAT)n and about 650 were sequenced. 120 PCR primers sequences bordering the microsatellite repeats were designed. For polymorphism assessment, 12 sunflower germplasms accessions are being checked, and 62 of the tested primers have shown to be polymorphic for the selected lines with polymorphic information content (PIC) average of 0.57. At the end of this step, we expect to reach the sequencing of 1000 positives clones with a rate of 10 to 14 % polymorphic microsatellite ready to map. * Buck, Cargill, Decalb, Mycogen, Nidera, Novartis, Sursem, Zeneca.