Assessment of genetic diversity in Iranian confectionary sunflower (Helianthus annuus L.) populations using retrotransposon based IRAP markers

Abstract

Genetic diversity is necessary for plant breeders to obtain new cultivars either with high yield, better quality, more adapted to abiotic stress or more resistant to pest and pathogens. Retrotransposons are current component of plant genomes. Ubiquitous, activity and abundant of retrotransposons thorough the plant genome, make them useful molecular marker. We used inter-retrotransposon amplified polymorphism (IRAP) markers to assess genomic diversity levels and survey the activity of LTR retrotransposon elements in 10 confectionary sunflower populations. Out of 25 single and combined IRAP primers, 11 primers produced scorable and polymorphic banding patterns. A total of 116 loci were amplified by using 11 IRAP primers on confectionary populations. 110 loci out of 116 were polymorphic. The lowest (0.74) and highest (0.88) Nei genetic similarity was observed between Hamedan and Mashhad and Marand and Esfahan populations, respectively. Cluster analysis based on UPGMA algorithm grouped the studied populations in 3 main classes. Analysis of molecular variance revealed that the high part of total variation was due to within populations. So it will be better to do selection within populations in breeding programs. The results showed that retrotransposons are active in sunflower genome and they are inserted in sunflower genome as head-to-head, head-to-tail and tail-to-tail orientations. Our results showed that retrotransposon-based molecular markers can be used as a valuable tool for genomic assessment in sunflower.

Keywords

• cluster analysis
• landrace
• retrotransposon
• sunflower
• molecular marker