Lanning S.P.,Montana State University |
Martin J.M.,Montana State University |
Stougaard R.N.,Northwestern Agriculture Res Center |
Guillen-Portal F.R.,Sustainable Oils LLC |
And 7 more authors.
Crop Science | Year: 2012
The most common genes for semidwarf habit in modern wheat (Triticum aestivum L.) cultivars are found at the Rht-B1 and Rht-D1 loci on chromosomes 4B and 4D, respectively. An alternative gene for semidwarf habit, Rht8, has shown potential as a replacement for Rht- B1b and Rht-D1b in some environments. The objective of the present study was to assess the impact of the height-reducing gene Rht8 relative to Rht-B1b and Rht-D1b on performance of spring wheat in Montana and Washington environments characterized by terminal drought stress. Evaluation of near-isogenic lines developed in four genetic backgrounds showed that Rht-B1b, Rht-D1b, and Rht8 caused height reduction of 19, 20, and 6.5%, respectively, relative to wildtype near-isogenic lines over 12 environments. An increase in grain yield was associated with reduced height for lines containing Rht-B1b and Rht-D1b based on means over the four genetic backgrounds and 10 environments. Height reduction and yield increase associated with Rht-B1b and Rht-D1b were significant in most environments. Lines with Rht8 yielded less than wild-type based on means over environments and in 3 of 10 individual environments. Reduced height lines with Rht-B1b and Rht-D1b tended to have a higher harvest index and more seed per spike than wild-type lines and reduced height lines with Rht8. In sum, our results suggest that Rht-B1b and Rht-D1b are superior to Rht8 as a source for height reduction for spring wheat in the tested environments. © Crop Science Society of America.
Hutcheon C.,Targeted Growth |
Ditt R.F.,Targeted Growth |
Beilstein M.,Texas A&M University |
Comai L.,University of California at Davis |
And 6 more authors.
BMC Plant Biology | Year: 2010
Background: Camelina sativa, an oilseed crop in the Brassicaceae family, has inspired renewed interest due to its potential for biofuels applications. Little is understood of the nature of the C. sativa genome, however. A study was undertaken to characterize two genes in the fatty acid biosynthesis pathway, fatty acid desaturase (FAD) 2 and fatty acid elongase (FAE) 1, which revealed unexpected complexity in the C. sativa genome.Results: In C. sativa, Southern analysis indicates the presence of three copies of both FAD2 and FAE1 as well as LFY, a known single copy gene in other species. All three copies of both CsFAD2 and CsFAE1 are expressed in developing seeds, and sequence alignments show that previously described conserved sites are present, suggesting that all three copies of both genes could be functional. The regions downstream of CsFAD2 and upstream of CsFAE1 demonstrate co-linearity with the Arabidopsis genome. In addition, three expressed haplotypes were observed for six predicted single-copy genes in 454 sequencing analysis and results from flow cytometry indicate that the DNA content of C. sativa is approximately three-fold that of diploid Camelina relatives. Phylogenetic analyses further support a history of duplication and indicate that C. sativa and C. microcarpa might share a parental genome.Conclusions: There is compelling evidence for triplication of the C. sativa genome, including a larger chromosome number and three-fold larger measured genome size than other Camelina relatives, three isolated copies of FAD2, FAE1, and the KCS17-FAE1 intergenic region, and three expressed haplotypes observed for six predicted single-copy genes. Based on these results, we propose that C. sativa be considered an allohexaploid. The characterization of fatty acid synthesis pathway genes will allow for the future manipulation of oil composition of this emerging biofuel crop; however, targeted manipulations of oil composition and general development of C. sativa should consider and, when possible take advantage of, the implications of polyploidy. © 2010 Hutcheon et al; licensee BioMed Central Ltd.
Liu X.,Targeted Growth |
Brost J.,Targeted Growth |
Hutcheon C.,Targeted Growth |
Guilfoil R.,Targeted Growth |
And 7 more authors.
In Vitro Cellular and Developmental Biology - Plant | Year: 2012
Camelina sativa is a promising under-exploited oilseed crop with potential to become a biofuel feedstock. The ability to transform C. sativa would allow for the rapid introduction of novel traits into this emerging crop. We report the development of an Agrobacterium-based floral dip transformation method, requiring no vacuum-infiltration step, with transformation efficiencies up to 0.8%. C. sativa cultivars Ames 26665, "Calena" A3U7761, Ames 1043, and "Celine" were tested using Agrobacterium tumefaciens strains GV3101, EHA105, and At503. Use of all strains and cultivars resulted in transformed plants; however, GV3101 was the only Agrobacterium strain and Ames 1043 the only C. sativa cultivar to yield transformed plants under all conditions tested. Progeny analysis revealed that in approximately 78% of the transformed plants, the transgene segregated as a single locus. Furthermore, a high-throughput, filter paper-based PCR method was developed to screen marker-free transformed plants. Together, these methods will allow for easier introduction of new genes into this promising oilseed crop. © 2012 The Society for In Vitro Biology.