Patterns of nucleotide diversity in wild and cultivated sunflower.

نویسندگان

  • Aizhong Liu
  • John M Burke
چکیده

Interest in the level and organization of nucleotide diversity in domesticated plant lineages has recently been motivated by the potential for using association-based mapping techniques as a means for identifying the genes underlying complex traits. To date, however, such data have been available only for a relatively small number of well-characterized plant taxa. Here we provide the first detailed description of patterns of nucleotide polymorphism in wild and cultivated sunflower (Helianthus annuus), using sequence data from nine nuclear genes. The results of this study indicate that wild sunflower harbors at least as much nucleotide diversity as has been reported in other wild plant taxa, with randomly selected sequence pairs being expected to differ at 1 of every 70 bp. In contrast, cultivated sunflower has retained only 40-50% of the diversity present in the wild. Consistent with this dramatic reduction in polymorphism, a phylogenetic analysis of our data revealed that the cultivars form a monophyletic clade, adding to the growing body of evidence that sunflower is the product of a single domestication. Eight of the nine loci surveyed appeared to be evolving primarily under purifying selection, while the remaining locus may have been the subject of positive selection. Linkage disequilibrium (LD) decayed very rapidly in the self-incompatible wild sunflower, with the expected LD falling to negligible levels within 200 bp. The cultivars, on the other hand, exhibited somewhat higher levels of LD, with nonrandom associations persisting up to approximately 1100 bp. Taken together, these results suggest that association-based approaches will provide a high degree of resolution for the mapping of functional variation in sunflower.

برای دانلود متن کامل این مقاله و بیش از 32 میلیون مقاله دیگر ابتدا ثبت نام کنید

ثبت نام

اگر عضو سایت هستید لطفا وارد حساب کاربری خود شوید

منابع مشابه

The Evaluation of Genomic Relationships and Diversity of Wild and Cultivated Wheats Possessing A Genome in Different Ploidy Levels Using SSR Markers

Genomic relationships and diversity of 37 wild and cultivated wheat (Triticum sp.) possessing A genome include four T. urartu (Au), thirteen wild einkorn (Am), four cultivated einkorn (Am), seven durum wheat (BBAuAu), three T. zhukovskyi (AtAtAmAmGG) and six com...

متن کامل

Single nucleotide polymorphisms and linkage disequilibrium in sunflower.

Genetic diversity in modern sunflower (Helianthus annuus L.) cultivars (elite oilseed inbred lines) has been shaped by domestication and breeding bottlenecks and wild and exotic allele introgression(-)the former narrowing and the latter broadening genetic diversity. To assess single nucleotide polymorphism (SNP) frequencies, nucleotide diversity, and linkage disequilibrium (LD) in modern cultiv...

متن کامل

Genome-wide high-throughput SNP discovery and genotyping for understanding natural (functional) allelic diversity and domestication patterns in wild chickpea

We identified 82489 high-quality genome-wide SNPs from 93 wild and cultivated Cicer accessions through integrated reference genome- and de novo-based GBS assays. High intra- and inter-specific polymorphic potential (66-85%) and broader natural allelic diversity (6-64%) detected by genome-wide SNPs among accessions signify their efficacy for monitoring introgression and transferring target trait...

متن کامل

Identification of a sex-linked SCAR marker for Plecoglossus altivelis and its application for identifying gender in cultivated and wild populations

Ayu (Plecoglossus altivelis), one kinds of valuable cultured fish species, show almost no morphological difference between male and female until sexual maturity. Here, we report the identification of sex-linked markers for the ayu, based on Amplified Fragment Length Polymorphism (AFLP) generated from cultured fish (15 males and 15 females) by using 63 different primer combinations. Genomic frag...

متن کامل

Comparison of Genetic Diversity in Species and Cultivars of Pistachio (Pistacia sp. L.) Based on Amplified Fragment Length Polymorphism (AFLP) Markers

The genetic diversity of a large number of pistachio genotypes grown in Iran is not exactly known. Most of the studies on genetic diversity of Iranian pistachio varieties are based on morphological characteristics or isozyme markers. In the present study, the genetic diversity of selected pistachio cultivars along with some wild species were evaluated by Amplified Fragment Length Polymorphism (...

متن کامل

ذخیره در منابع من


  با ذخیره ی این منبع در منابع من، دسترسی به آن را برای استفاده های بعدی آسان تر کنید

برای دانلود متن کامل این مقاله و بیش از 32 میلیون مقاله دیگر ابتدا ثبت نام کنید

ثبت نام

اگر عضو سایت هستید لطفا وارد حساب کاربری خود شوید

عنوان ژورنال:
  • Genetics

دوره 173 1  شماره 

صفحات  -

تاریخ انتشار 2006