Jalons théologiques et stratégiques pour un engagement ecclésial socialement transformateur au Québec : enseignement et promesses d'une pratique de pastorale sociale à Granby

Mémoire numérisé par la Direction des bibliothèques de l'Université de Montréal

Persistence of rye (Secale cereale L.) chromosome arm 1RS in wheat (Triticum aestivum L.) breeding programs of the Great Plains of North America

Rye (Secale cereale L.) chromosome arm 1RS has been used world-wide by wheat (Triticum aestivum L.) breeding programs as a source of pestand pathogen-resistance genes, and to improve grain yield and stress tolerance. The most common vehicles used to access 1RS are various 1AL.1RS and 1BL.1RS wheat-rye chromosomal translocations. Over the past 25 years, advanced North American wheat breeding lines were evaluated, first by assay of secalin storage proteins, and later by use of DNA marker TSM0120, for the presence of these two translocations. Both methods provide accurate and efficient means of identifying and differentiating 1BL.1RS and 1A.1RS. Both 1Al.1RS and 1BL.1RS wheats were found in all tested years. 1AL.1RS lines were more common in southern Great Plains breeding programs. 1AL.1RS lines were released as cultivars at a frequency identical to that of wild-type breeding lines. In contrast, 1BL.1RS breeding lines were developed by breeding programs throughout the Great Plains, but fewer were released as cultivars. Both 1RS translocation types persist in Great Plains breeding programs. The lower rate of release of 1BL.1RS cultivars no doubt is a consequence of the more drastic effects on breadmaking quality relative to those observed with 1AL.1RS

Identification of markers linked to genes for sprouting tolerance (independent of grain color) in hard white winter wheat (HWWW)

Key message Hard red wheats can donate genes to hard white wheats for tolerance to preharvest sprouting, the effects are quantitative in nature, and may be tracked with previously described DNA markers. Abstract Pre-harvest sprouting (PHS) of wheat (Triticum aestivum L.) can negatively impact end-use quality and seed viability at planting. Due to preferences for white over red wheat in international markets, white wheat with PHS tolerance has become increasingly desired for worldwide wheat production. In general, however, red wheat is more tolerant of sprouting than white wheat. The main objective of this study was the identification of PHS tolerance conditioned by genes donated from hard red winter wheat, using markers applicable to the Great Plains hard white wheat gene pool. Three red wheat by white wheat populations, Niobrara/NW99L7068, NE98466/NW99L7068 and Jagalene/ NW99L7068 were developed, and white-seeded progenies were analyzed for PHS tolerance and used to identify markers for the trait. In the three populations, marker loci with significant allelic effects were most commonly located on chromosomes of group 2, 3, 4 and 5, though additional markers were detected across the wheat genome. Chromosome 3A was the only chromosome with significant markers in all three populations. Markers were inconsistent across the three populations, and markers linked to tolerance-inducing loci were identified in both tolerant and susceptible parents. Additive effects of marker loci were common. In the present investigation, a wide range of PHS tolerance was observed, even though all lines were fixed for the recently reported positive TaPHS1 allele. PHS tolerance is controlled by additive major gene effects with minor gene effects where variations of minor gene effects were still unclear

Local adaptation, genetic divergence, and experimental selection in a foundation grass across the US Great Plains’ climate gradient

Many prior studies have uncovered evidence for local adaptation using reciprocal transplant experiments. However, these studies are rarely conducted for a long enough time to observe succession and competitive dynamics in a community context, limiting inferences for long-lived species. Furthermore, the genetic basis of local adaptation and genetic associations with climate has rarely been identified. Here, we report on a long-term (6-year) experiment conducted under natural conditions focused on Andropogon gerardii, the dominant grass of the North American Great Plains tallgrass ecosystem. We focus on this foundation grass that comprises 80% of tallgrass prairie biomass and is widely used in 20,000 km 2 of restoration. Specifically, we asked the following questions: (a) Whether ecotypes are locally adapted to regional climate in realistic ecological communities. (b) Does adaptive genetic variation underpin divergent phenotypes across the climate gradient? (c) Is there evidence of local adaptation if the plants are exposed to competition among ecotypes in mixed ecotype plots? Finally, (d) are local adaptation and genetic divergence related to climate? Reciprocal gardens were planted with 3 regional ecotypes (originating from dry, mesic, wet climate sources) of Andropogon gerardii across a precipitation gradient (500–1,200 mm/year) in the US Great Plains. We demonstrate local adaptation and differentiation of ecotypes in wet and dry environments. Surprisingly, the apparent generalist mesic ecotype performed comparably under all rainfall conditions. Ecotype performance was underpinned by differences in neutral diversity and candidate genes corroborating strong differences among ecotypes. Ecotype differentiation was related to climate, primarily rainfall. Without long-term studies, wrong conclusions would have been reached based on the first two years. Further, restoring prairies with climate-matched ecotypes is critical to future ecology, conservation, and sustainability under climate change

Registration of ‘Matterhorn’ Hard White Waxy Winter Wheat

‘Matterhorn’ (Reg. No. CV-1151, PI 687896) hard white winter waxy wheat (Triticum aestivum L.) was developed cooperatively by the USDA-ARS and the Nebraska Agricultural Experiment Station and released in 2018. Matterhorn, a sibling of the hard red waxy cultivar Mattern, has white grain color and waxy (amylose-free) endosperm starch. It was released primarily for its unique end-use quality attributes and for grain yield competitiveness with currently grown Nebraskaadapted cultivars. The waxy starch is conditioned by the presence of three naturally occurring mutations that eliminate production of the enzyme granule-bound starch synthase. Granule-bound starch synthase synthesizes amylose in typical wheats and other cereal crops. Matterhorn (tested as NX04Y2107W) was selected from the heterogeneous red/ white-seeded experimental line NX04Y2107 derived from the cross NW98S061/99Y1442

Adaptive genetic potential and plasticity of trait variation in the foundation prairie grass Andropogon gerardii across the US Great Plains’ climate gradient: Implications for climate change and restoration

Plant response to climate depends on a species’ adaptive potential. To address this, we used reciprocal gardens to detect genetic and environmental plasticity effects on phenotypic variation and combined with genetic analyses. Four reciprocal garden sites were planted with three regional ecotypes of Andropogon gerardii, a dominant Great Plains prairie grass, using dry, mesic, and wet ecotypes originating from western KS to Illinois that span 500–1,200 mm rainfall/year. We aimed to answer: (a) What is the relative role of genetic constraints and phenotypic plasticity in controlling phenotypes? (b) When planted in the homesite, is there a trait syndrome for each ecotype? (c) How are genotypes and phenotypes structured by climate? and (d) What are implications of these results for response to climate change and use of ecotypes for restoration? Surprisingly, we did not detect consistent local adaptation. Rather, we detected co-gradient variation primarily for most vegetative responses. All ecotypes were stunted in western KS. Eastward, the wet ecotype was increasingly robust relative to other ecotypes. In contrast, fitness showed evidence for local adaptation in wet and dry ecotypes with wet and mesic ecotypes producing little seed in western KS. Earlier flowering time in the dry ecotype suggests adaptation to end of season drought. Considering ecotype traits in homesite, the dry ecotype was characterized by reduced canopy area and diameter, short plants, and low vegetative biomass and putatively adapted to water limitation. The wet ecotype was robust, tall with high biomass, and wide leaves putatively adapted for the highly competitive, light-limited Eastern Great Plains. Ecotype differentiation was supported by random forest classification and PCA. We detected genetic differentiation and outlier genes associated with primarily precipitation. We identified candidate gene GA1 for which allele frequency associated with plant height. Sourcing of climate adapted ecotypes should be considered for restoration

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

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

Missense Mutations in the MEFV Gene Are Associated with Fibromyalgia Syndrome and Correlate with Elevated IL-1β Plasma Levels

BACKGROUND:Fibromyalgia syndrome (FMS), a common, chronic, widespread musculoskeletal pain disorder found in 2% of the general population and with a preponderance of 85% in females, has both genetic and environmental contributions. Patients and their parents have high plasma levels of the chemokines MCP-1 and eotaxin, providing evidence for both a genetic and an immunological/inflammatory origin for the syndrome (Zhang et al., 2008, Exp. Biol. Med. 233: 1171-1180). METHODS AND FINDINGS:In a search for a candidate gene affecting inflammatory pathways, among five screened in our patient samples (100 probands with FMS and their parents), we found 10 rare and one common alleles for MEFV, a gene in which various compound heterozygous mutations lead to Familial Mediterranean Fever (FMF). A total of 2.63 megabases of genomic sequence of the MEFV gene were scanned by direct sequencing. The collection of rare missense mutations (all heterozygotes and tested in the aggregate) had a significant elevated frequency of transmission to affecteds (p = 0.0085, one-sided, exact binomial test). Our data provide evidence that rare missense variants of the MEFV gene are, collectively, associated with risk of FMS and are present in a subset of 15% of FMS patients. This subset had, on average, high levels of plasma IL-1beta (p = 0.019) compared to FMS patients without rare variants, unaffected family members with or without rare variants, and unrelated controls of unknown genotype. IL-1beta is a cytokine associated with the function of the MEFV gene and thought to be responsible for its symptoms of fever and muscle aches. CONCLUSIONS:Since misregulation of IL-1beta expression has been predicted for patients with mutations in the MEFV gene, we conclude that patients heterozygous for rare missense variants of this gene may be predisposed to FMS, possibly triggered by environmental factors

Persistence of rye (Secale cereale L.) chromosome arm 1RS in wheat (Triticum aestivum L.) breeding programs of the Great Plains of North America

Rye (Secale cereale L.) chromosome arm 1RS has been used world-wide by wheat (Triticum aestivum L.) breeding programs as a source of pestand pathogen-resistance genes, and to improve grain yield and stress tolerance. The most common vehicles used to access 1RS are various 1AL.1RS and 1BL.1RS wheat-rye chromosomal translocations. Over the past 25 years, advanced North American wheat breeding lines were evaluated, first by assay of secalin storage proteins, and later by use of DNA marker TSM0120, for the presence of these two translocations. Both methods provide accurate and efficient means of identifying and differentiating 1BL.1RS and 1A.1RS. Both 1Al.1RS and 1BL.1RS wheats were found in all tested years. 1AL.1RS lines were more common in southern Great Plains breeding programs. 1AL.1RS lines were released as cultivars at a frequency identical to that of wild-type breeding lines. In contrast, 1BL.1RS breeding lines were developed by breeding programs throughout the Great Plains, but fewer were released as cultivars. Both 1RS translocation types persist in Great Plains breeding programs. The lower rate of release of 1BL.1RS cultivars no doubt is a consequence of the more drastic effects on breadmaking quality relative to those observed with 1AL.1RS