349 research outputs found

    QTL Mapping of a High Protein Digestibility Trait in Sorghum bicolor

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    Compared with other cereal grains, Sorghum bicolor shows lower protein digestibility. The low digestibility is thought to result from disulfide cross linking in the β- and γ-kafirins. In contrast, the single recessive high digestibility/high lysine content (HD) mutation which confers greater grain digestibility exists in sorghum that is thought to result from reduced accumulation of γ-kafirin that allows greater access to the high digestible α-kafarin fraction. In an effort to both clearly define the molecular basis for the HD trait and develop tools to improve the introgression of this difficult-to-screen trait, this study focuses on mapping the QTLs linked to this trait. While the HD trait has been defined as a single recessive gene, our results uncovered that two major QTLs on chromosome 1 are associated with protein digestibility—one QTL (locus 1 from the HD parent) unfavorably affects digestibility and one QTL (locus 2 from the HD parent) only 20 cM away favorably affects digestibility. A contrast analysis between genotypic groups at these two loci shows that a higher level of protein digestibility may be obtained when this linkage in repulsion is broken and favorable alleles are allowed to recombine

    Influence of high protein digestibility sorghums on free amino nitrogen (FAN) production during malting and mashing

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    In sorghum brewing, obtaining sufficient Free Amino Nitrogen (FAN) for rapid and complete fermentation remains a problem due to the high proportions of unmalted sorghum used and the poor digestibility of wet-heat treated sorghum protein. Sorghum mutant lines with high protein digestibility have been developed through breeding. These high protein digestibility sorghums (HPDS) have protein bodies with villi-like borders that apparently facilitate protease access. This work investigated FAN production from HPDS when malted and mashed, to assess their potential for use in sorghum brewing to improve wort FAN levels. When malted, HPDS contained substantially higher levels of FAN than normal protein digestibility sorghums (NPDS), 32 mg/100 g malt more. However, when the HPDS were mashed either as malt, or as grain or malt plus exogenous proteases, FAN production during mashing was not substantially higher than with NPDS subjected to the same treatments, only 6, 6–18 and 9–13 mg/100 g grain or malt, respectively. This is probably due to wet-heat induced cross-linking of the kafirin proteins reducing their susceptibility to proteolysis. Notwithstanding this, HPDS could be very useful for improving FAN levels in sorghum brewing if they are malted. sorghum this is a particular issue as the grists often comprise a low proportion of malt relative to unmalted adjunct or even 100% unmalted sorghum. Recent work on improving FAN production in sorghum brewing has focused on the use of exogenous proteases7,10,12. However, it appears that to achieve sufficient proteolysis of the sorghum proteins, excessively high levels of exogenous proteases may be required. This can be attributed to the poor digestibility of the sorghum kafirin storage protein3, when it has been subjected to wet-heat treatment, as occurs in the brewing process. Weaver and co-workers at Purdue University identified mutant sorghum lines with improved protein digestibility23. These high protein digestibility sorghums (HPDS) were developed by crossing normal sorghum lines with a high-lysine sorghum mutant. More recently, research at Texas A&M University has focused on breeding to improve the agronomic and end-use quality of the HPDS, and determination of quantitative trait loci (QTLs) for the HPD trait24. This work therefore investigated FAN production from HPDS when malted and mashed, with the objective of assessing their potential for use in sorghum brewing to improve wort FAN levels.The International Sorghum, Millet and Other Grains Collaborative Research Support Program (INTSORMIL), Sun Grant Program, US Department of Transportation, Project No. DTOS59-07-G-00056 to D.B. Hays, Novozymes SA, Mr J. van Aswegen, Mr I. Kennedy and Mr B. Higgins.http://onlinelibrary.wiley.com/journal/10.1002/(ISSN)2050-041

    Novel biofortified sorghum lines with combined waxy (high amylopectin) starch and high protein digestibility traits : effects on endosperm and flour properties

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    Novel biofortified sorghum lines have been developed with both waxy starch (high amylopectin) and high protein digestibility traits. Eight sorghum lines with different combinations of waxy, non-waxy, high- and normal-protein digestibility traits were studied in relation to flour properties. Lines with the high protein digestibility trait had loosely packed starch granules and floury endosperm, irrespective of whether they were waxy or non-waxy. In terms of thermal properties, combined waxy-high digestibility lines had the highest onset endothermic temperature as well as endothermic energy compared to non-waxy, normal protein digestibility lines. The waxy-high protein digestibility lines had higher paste viscosity and formed much softer and less sticky pastes than the non-waxy, normal protein digestibility lines. Flours of the combined waxy-high protein digestibility sorghum lines had much higher solubility than the non-waxy- normal protein digestibility lines. At 30 C flour solubility, waxy-high protein digestibility sorghum lines flour was similar to commercial wheat bread flours. The high flour solubility, high pasting viscosity and soft paste of sorghum lines with combined waxy and high protein digestibility traits indicate that their flours may have better properties for making dough-based food products than normal non-waxy, normal protein digestibility sorghums.Howard G. Buffett Foundation through the Norman E. Borlaug Institute for International Agriculture of Texas A&M AgriLife Research and by the US- Department of Transportation Subgrant 2011. University of Pretoria Research Support Bursary.http://www.elsevier.com/locate/jcs2016-09-30hb2016Food Scienc

    QTL mapping of yield components and kernel traits in wheat cultivars TAM 112 and Duster

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    In the Southern Great Plains, wheat cultivars have been selected for a combination of outstanding yield and drought tolerance as a long-term breeding goal. To understand the underlying genetic mechanisms, this study aimed to dissect the quantitative trait loci (QTL) associated with yield components and kernel traits in two wheat cultivars `TAM 112' and `Duster' under both irrigated and dryland environments. A set of 182 recombined inbred lines (RIL) derived from the cross of TAM 112/Duster were planted in 13 diverse environments for evaluation of 18 yield and kernel related traits. High-density genetic linkage map was constructed using 5,081 single nucleotide polymorphisms (SNPs) from genotyping-by-sequencing (GBS). QTL mapping analysis detected 134 QTL regions on all 21 wheat chromosomes, including 30 pleiotropic QTL regions and 21 consistent QTL regions, with 10 QTL regions in common. Three major pleiotropic QTL on the short arms of chromosomes 2B (57.5 - 61.6 Mbps), 2D (37.1 - 38.7 Mbps), and 7D (66.0 - 69.2 Mbps) colocalized with genes Ppd-B1, Ppd-D1, and FT-D1, respectively. And four consistent QTL associated with kernel length (KLEN), thousand kernel weight (TKW), plot grain yield (YLD), and kernel spike-1 (KPS) (Qklen.tamu.1A.325, Qtkw.tamu.2B.137, Qyld.tamu.2D.3, and Qkps.tamu.6A.113) explained more than 5% of the phenotypic variation. QTL Qklen.tamu.1A.325 is a novel QTL with consistent effects under all tested environments. Marker haplotype analysis indicated the QTL combinations significantly increased yield and kernel traits. QTL and the linked markers identified in this study will facilitate future marker-assisted selection (MAS) for pyramiding the favorable alleles and QTL map-based cloning.Horticulture and Landscape Architectur

    Minimal changes in health status questionnaires: distinction between minimally detectable change and minimally important change

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    Changes in scores on health status questionnaires are difficult to interpret. Several methods to determine minimally important changes (MICs) have been proposed which can broadly be divided in distribution-based and anchor-based methods. Comparisons of these methods have led to insight into essential differences between these approaches. Some authors have tried to come to a uniform measure for the MIC, such as 0.5 standard deviation and the value of one standard error of measurement (SEM). Others have emphasized the diversity of MIC values, depending on the type of anchor, the definition of minimal importance on the anchor, and characteristics of the disease under study. A closer look makes clear that some distribution-based methods have been merely focused on minimally detectable changes. For assessing minimally important changes, anchor-based methods are preferred, as they include a definition of what is minimally important. Acknowledging the distinction between minimally detectable and minimally important changes is useful, not only to avoid confusion among MIC methods, but also to gain information on two important benchmarks on the scale of a health status measurement instrument. Appreciating the distinction, it becomes possible to judge whether the minimally detectable change of a measurement instrument is sufficiently small to detect minimally important changes

    Fructan and its relationship to abiotic stress tolerance in plants

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    Numerous studies have been published that attempted to correlate fructan concentrations with freezing and drought tolerance. Studies investigating the effect of fructan on liposomes indicated that a direct interaction between membranes and fructan was possible. This new area of research began to move fructan and its association with stress beyond mere correlation by confirming that fructan has the capacity to stabilize membranes during drying by inserting at least part of the polysaccharide into the lipid headgroup region of the membrane. This helps prevent leakage when water is removed from the system either during freezing or drought. When plants were transformed with the ability to synthesize fructan, a concomitant increase in drought and/or freezing tolerance was confirmed. These experiments indicate that besides an indirect effect of supplying tissues with hexose sugars, fructan has a direct protective effect that can be demonstrated by both model systems and genetic transformation

    Juxtaposing BTE and ATE – on the role of the European insurance industry in funding civil litigation

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    One of the ways in which legal services are financed, and indeed shaped, is through private insurance arrangement. Two contrasting types of legal expenses insurance contracts (LEI) seem to dominate in Europe: before the event (BTE) and after the event (ATE) legal expenses insurance. Notwithstanding institutional differences between different legal systems, BTE and ATE insurance arrangements may be instrumental if government policy is geared towards strengthening a market-oriented system of financing access to justice for individuals and business. At the same time, emphasizing the role of a private industry as a keeper of the gates to justice raises issues of accountability and transparency, not readily reconcilable with demands of competition. Moreover, multiple actors (clients, lawyers, courts, insurers) are involved, causing behavioural dynamics which are not easily predicted or influenced. Against this background, this paper looks into BTE and ATE arrangements by analysing the particularities of BTE and ATE arrangements currently available in some European jurisdictions and by painting a picture of their respective markets and legal contexts. This allows for some reflection on the performance of BTE and ATE providers as both financiers and keepers. Two issues emerge from the analysis that are worthy of some further reflection. Firstly, there is the problematic long-term sustainability of some ATE products. Secondly, the challenges faced by policymakers that would like to nudge consumers into voluntarily taking out BTE LEI

    Penilaian Kinerja Keuangan Koperasi di Kabupaten Pelalawan

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    This paper describe development and financial performance of cooperative in District Pelalawan among 2007 - 2008. Studies on primary and secondary cooperative in 12 sub-districts. Method in this stady use performance measuring of productivity, efficiency, growth, liquidity, and solvability of cooperative. Productivity of cooperative in Pelalawan was highly but efficiency still low. Profit and income were highly, even liquidity of cooperative very high, and solvability was good

    Search for stop and higgsino production using diphoton Higgs boson decays

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    Results are presented of a search for a "natural" supersymmetry scenario with gauge mediated symmetry breaking. It is assumed that only the supersymmetric partners of the top-quark (stop) and the Higgs boson (higgsino) are accessible. Events are examined in which there are two photons forming a Higgs boson candidate, and at least two b-quark jets. In 19.7 inverse femtobarns of proton-proton collision data at sqrt(s) = 8 TeV, recorded in the CMS experiment, no evidence of a signal is found and lower limits at the 95% confidence level are set, excluding the stop mass below 360 to 410 GeV, depending on the higgsino mass
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