Development of high amylose wheat through TILLING

BMC Plant Biology

Research Article

Gia Fazio¹  John F Goodstal¹  Cate McGuire¹  Wayne Skinner¹  Kali M Brandt²  Vic C Knauf²  Aaron Holm²  Ann J Slade²  Dayna Loeffler²  Jessica Mullenberg²  Michael N Steine² 

[1] Arcadia Biosciences, Inc, 202 Cousteau Pl, Suite 200, 95618, Davis, CA, USA;Arcadia Biosciences, Inc, 410 West Harrison St, Suite 150, 98119, Seattle, WA, USA;

关键词: Amylose;    Bread Wheat;    Durum Wheat;    Starch Granule;    Amylose Content;   

DOI  :  10.1186/1471-2229-12-69

 received in 2011-12-23, accepted in 2012-05-14,  发布年份 2012

来源: Springer

【 摘 要 】

BackgroundWheat (Triticum spp.) is an important source of food worldwide and the focus of considerable efforts to identify new combinations of genetic diversity for crop improvement. In particular, wheat starch composition is a major target for changes that could benefit human health. Starches with increased levels of amylose are of interest because of the correlation between higher amylose content and elevated levels of resistant starch, which has been shown to have beneficial effects on health for combating obesity and diabetes. TILLING (Targeting Induced Local Lesions in Genomes) is a means to identify novel genetic variation without the need for direct selection of phenotypes.ResultsUsing TILLING to identify novel genetic variation in each of the A and B genomes in tetraploid durum wheat and the A, B and D genomes in hexaploid bread wheat, we have identified mutations in the form of single nucleotide polymorphisms (SNPs) in starch branching enzyme IIa genes (SBEIIa). Combining these new alleles of SBEIIa through breeding resulted in the development of high amylose durum and bread wheat varieties containing 47-55% amylose and having elevated resistant starch levels compared to wild-type wheat. High amylose lines also had reduced expression of SBEIIa RNA, changes in starch granule morphology and altered starch granule protein profiles as evaluated by mass spectrometry.ConclusionsWe report the use of TILLING to develop new traits in crops with complex genomes without the use of transgenic modifications. Combined mutations in SBEIIa in durum and bread wheat varieties resulted in lines with significantly increased amylose and resistant starch contents.

【 授权许可】

CC BY   
© Slade et al.; licensee BioMed Central Ltd. 2012