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831.
The phylogeny of prokaryotes 总被引:92,自引:0,他引:92
832.
L. T. Hickey W. Lawson V. N. Arief G. Fox J. Franckowiak M. J. Dieters 《Euphytica》2012,188(1):113-122
Grain dormancy provides protection against pre-harvest sprouting (PHS) in cereals. Composite interval mapping and association analyses were performed to identify quantitative trait loci (QTL) contributing grain dormancy in a doubled haploid (DH) barley population (ND24260?×?Flagship) consisting of 321 lines genotyped with DArT markers. Harvest-ripe grain collected from three field experiments was germinated over a 7-day period to determine a weighted germination index for each line. DH lines displaying moderate to high levels of grain dormancy were identified; however, both parental lines were non-dormant and displayed rapid germination within the first two?days of testing. Genetic analysis identified two QTL on chromosome 5H that were expressed consistently in each of the three environments. One QTL (donated by Flagship) was located close to the centromeric region of chromosome 5H (qSDFlag), accounting for up to 15% of the phenotypic variation. A second QTL with a larger effect (from ND24260) was detected on chromosome 5HL (qSDND), accounting for up to 35% of the phenotypic variation. qSDFlag and qSDND displayed an epistatic interaction and DH lines that had the highest levels of grain dormancy carried both genes. We demonstrate that qSDND in the ND24260?×?Flagship DH population is positioned proximal and independent to the well-characterised SD2 region that is associated with both high levels of dormancy and inferior malt quality. This indicates that it should be possible to develop cultivars that combine acceptable malting quality and adequate levels of grain dormancy for protection against PHS by utilizing these alternate QTL. 相似文献
833.
Peter W. Gous Anke Martin Wendy Lawson Alison Kelly Glen P. Fox Mark W. Sutherland 《Euphytica》2012,185(1):37-45
Barley (Hordeum vulgare) is a major feed source for the intensive livestock industry. Competitiveness against other cereal grains depends largely
on the price per unit of expressed feed quality. The traits which contribute to feed quality in barley are largely quantitative
in nature but little is known about their genetic control. A study to identify the quantitative trait loci (QTLs) associated
with feed quality was performed using a F6-derived recombinant inbred barley population. Samples from each line were incubated
in the rumen of fistulated cattle, recovered, washed and dried for determination of in situ dry matter digestibility. Additionally,
both pre- and post-digestion samples were analysed to quantify the content of key quality components relating to acid detergent
fibre, total starch and protein. The data was used to identify trait-associated QTLs. Genetic analysis identified significant
QTLs on chromosomes 2H, 5H and 7H. Genetic markers linked to these QTL should provide an effective tool for the selection
and improvement of feed barley in the future. 相似文献
834.
Location Decision Making of “Creative” Industries: The Media and Computer Game Sectors in Dublin,Ireland 下载免费PDF全文
There has been significant research undertaken examining the “creative class” thesis within the context of the locational preferences of creative workers. However, relatively little attention has been given to the locational preferences of creative companies within the same context. This paper reports on research conducted to qualitatively analyse the location decision making of companies in two creative sectors: media and computer games. We address the role of the so‐called “hard” and “soft” factors in company location decision making within the context of the creative class thesis, which suggests that company location is primarily determined by “soft” factors rather than “hard” factors. The study focuses upon “core” creative industries in the media and computer game sectors and utilises interview data with company managers and key elite actors in the sector to investigate the foregoing questions. The results show that “hard” factors are of primary importance for the location decision making in the sectors analysed, but that “soft” factors play quite an important role when “hard” factors are satisfactory in more than one competing city‐region. 相似文献
835.
Muller CB Ride SM Fouke J Whitney T Denton DD Cantor N Nelson DJ Plummer J Busch-Vishniac I Meyers C Rosser SV Schiebinger L Roberts E Burgess D Beeson C Metz SS Sanders L Watford BA Ivey ES Frank Fox M Wettack S Klawe M Wulf WA Girgus J Leboy PS Babco EL Shanahan B Didion C Chubin DE Frize M Ganter SL Nalley EA Franz J Abruña HD Strober MH Zimmer Daniels J Carter EA Rhodes JH Schrijver I Zakian VA Simons B Martin U Boaler J Jolluck KR Mankekar P Gray RM Conkey MW Stansky P Xie A Martin P 《Science (New York, N.Y.)》2005,307(5712):1043
836.
Burrows DN Romano P Falcone A Kobayashi S Zhang B Moretti A O'brien PT Goad MR Campana S Page KL Angelini L Barthelmy S Beardmore AP Capalbi M Chincarini G Cummings J Cusumano G Fox D Giommi P Hill JE Kennea JA Krimm H Mangano V Marshall F Mészáros P Morris DC Nousek JA Osborne JP Pagani C Perri M Tagliaferri G Wells AA Woosley S Gehrels N 《Science (New York, N.Y.)》2005,309(5742):1833-1835
Gamma-ray burst (GRB) afterglows have provided important clues to the nature of these massive explosive events, providing direct information on the nearby environment and indirect information on the central engine that powers the burst. We report the discovery of two bright x-ray flares in GRB afterglows, including a giant flare comparable in total energy to the burst itself, each peaking minutes after the burst. These strong, rapid x-ray flares imply that the central engines of the bursts have long periods of activity, with strong internal shocks continuing for hundreds of seconds after the gamma-ray emission has ended. 相似文献
837.
Responses of species to climate change are extremely variable, perhaps because of climate-related changes to interactions among species. We show that temperature-related changes in the dependence of the butterfly Aricia agestis on different larval host plants have facilitated rapid range expansion. Historically, the butterfly was largely restricted to a single plant species, Helianthemum nummularium, but recent warmer conditions have enabled the butterfly to increasingly use the more widespread plant species Geranium molle. This has resulted in a substantial increase in available habitat and rapid range expansion by the butterfly (79 kilometers northward in Britain in 20 years). Interactions among species are often seen as constraints on species' responses to climate change, but we show that temperature-dependent changes to interspecific interactions can also facilitate change. 相似文献
838.
One waxy and three regular yellow dent corn hybrids were wet milled by using two scales of laboratory procedures (modified 100-g and 1-kg) and a pilot-plant procedure (10-kg). The modified 100-g and 1-kg laboratory procedures gave similar yields of wet-milling fractions. Starch yields and recoveries were significantly lower for the pilot-plant procedure, whereas gluten and fiber yields were greater because of their high contents of unrecovered starch. Protein contents of the starches obtained by all three procedures were within commercially acceptable limits (<0.50% db for normal dent corn and <0.30% for waxy corn). Rankings for starch yields and starch recoveries for the four hybrids, having very different physical and compositional properties, were the same for all three procedures. The harder the grain, the lower the yield and recovery of starch. Least significant differences (P < 0.05) for starch yield were 0.8% for the modified 100-g procedure, 1.2% for the 1-kg procedure, and 2.0% for the pilot-plant procedure. 相似文献
839.
Oswaldo Taboada‐Gaytan Linda M. Pollak Lawrence A. Johnson Steven R. Fox Kevin T. Montgomery 《Cereal Chemistry》2010,87(3):175-181
Hybrids with high grain yield and higher starch, protein, or oil content are available to corn growers; however, they result from crossing adapted Corn Belt inbred lines that rarely include exotic germplasm. This study was conducted to determine whether Corn Belt lines introgressed with exotic materials from Argentina, Chile, Uruguay, Cuba, and Florida have appropriate wet‐milling characteristics in their hybrids. Ten lines from the Germplasm Enhancement of Maize (GEM) project with different starch contents were crossed to three adapted inbred lines used as testers. The B73×Mo17 hybrid was used as a control. The F1 generation of these 30 experimental hybrids was analyzed using both near‐infrared transmittance (NIT) technology and a 100‐g modified wet‐milling procedure, and measuring test and 1,000‐kernel weight. There was great variation among physical, compositional, and wet‐milling characteristics of the experimental hybrids, suggesting that exotic germplasm can be used to improve wet‐milling characteristics of Corn Belt hybrids. 相似文献