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Fusarium head blight (FHB) is a destructive disease in wheat (Triticum aestivum) and other small grains. Morphological traits can act as barrier between pathogen and plant and provide a passive form of resistance to disease. The objectives were: (1) to phenotype 250 soft red winter wheat (SRWW) breeding lines and cultivars for morphological traits in 2015–2016; (2) to estimate their correlations with disease resistance; and (3) to identify QTL for morphological traits associated with FHB resistance through genome-wide association study (GWAS). Morphological traits measured were anther extrusion, plant height, peduncle length, spike length (SL), spikelet number (SN), spike density (SD), spike inclination (SI). Agronomic traits included heading date and yield. Disease traits were: FHB-rating, incidence, severity, FHB-index, Fusarium damaged kernels and deoxynivalenol (DON) concentration. There were significant (p < 0.01) differences among genotypes for all morphological traits measured. Moderate heritabilities (0.41–0.66) for spike traits were estimated. Morphological and disease traits were generally negatively correlated; e.g. there was a significant (p < 0.01) negative correlation between spike inclination and DON. GWAS identified 29 significant (p < 0.001) SNPs associated with morphological traits, ranging from − 3.54 to 9.58% of the trait mean. Potential SNPs for yield were located on chromosomes 1B, 3B and 6A. Despite the small effects identified for the SNPs, several morphological traits should be considered for phenotypic and/or genomic selection in FHB resistance breeding programs. [ABSTRACT FROM AUTHOR]

Fusarium head blight (FHB) is an important disease of wheat (Triticum aestivum L.) that has caused billions of dollars in losses in recent decades. Although a massive breeding effort has been undertaken on multiple continents, there are no wheat cultivars with immunity to the disease. Resistance is conditioned by multiple loci and is further complicated by the role of the environment in expression of the disease phenotype. The objectives of our study were (i) to evaluate the phenotypic response to FHB in a large, diverse soft red winter wheat mapping panel; and (ii) to identify promising quantitative trait loci (QTL) associated with FHB resistance based on a genome‐wide association study (GWAS). We evaluated the mapping panel in 2014–2015 and 2015–2016 in an irrigated, inoculated scab nursery near Lexington, KY. Traits evaluated were heading date, plant height, FHB rating, severity, incidence, index, Fusarium‐damaged kernels (FDK), and deoxynivalenol (DON). There were significant (p < 0.05) differences among genotypes for all traits measured. The GWAS (based on 2‐yr entry means) identified 16 significant (p < 0.001) single nucleotide polymorphisms (SNPs) associated with disease traits on multiple chromosomes. Single nucleotide polymorphism association ranged from −2.14 to 4.01% of the mean of a given trait. We detected SNPs associated with FDK and DON on chromosomes 4A, 5B and 6B, and these SNPs decreased DON levels by 1.5, 2.1 and 3.2 mg kg−1, respectively. Our study demonstrated that even small‐effect QTL can potentially decrease disease levels and thus be useful in breeding programs. [ABSTRACT FROM AUTHOR]

Global temperature increases will affect Fusarium head blight (FHB) levels in wheat (Triticum aestivum L.). A pressing question is whether current sources of resistance will be effective in a warmer environment. We evaluated phenotypic response to disease in 238 soft winter wheat breeding lines and cultivars grown in 2015-2016 and 2016-2017 under control and warmed (+3 °C) conditions. Warming was achieved with heating cables buried 3 cm in the rhizosphere. We measured heading date, plant height, yield, FHB rating, Fusarium damaged kernels (FDK), deoxynivalenol (DON), leaf blotch rating, powdery mildew rating and leaf rust rating. There were significant (p < 0.01) differences among genotypes for all traits measured. Genome-wide association study (GWAS) identified 19 and 10 significant SNPs in the control and warmed treatments, respectively. FDK and DON levels were often significantly (p < 0.05) higher in warmed than in control when we contrasted alleles at important quantitative trait locus (QTL) such as Fhb1, Rht-B1 and D1 and all vernalization and photoperiod loci. Increased rhizosphere temperature resulted in a significantly (p < 0.01) earlier heading date (~3.5 days) both years of the study. Rank correlation between warmed and control treatments was moderate (r = 0.56). Though encouraging, it indicates that selection for performance under warming should be carried out in a warmed environment. [ABSTRACT FROM AUTHOR]

There has been a strong demand for oat genotypes that contain caryopsis with high chemical quality which can suit the different market niches. Therefore, the objectives of this study were to assess the general (GCA) and specific combining ability (SCA) of white oat cultivars through diallelic crosses providing information about the genetic effects on expression of grain chemical quality components. Also, it was aimed to estimate the heterosis on F and F generations and the vigor loss due to inbreeding. During 2008, 21 hybrid populations F and F were obtained from artificial crossing among seven Brazilian white oat cultivars, following the complete diallel design, without considering the reciprocals. These populations and their parents were evaluated in the 2009 season in the experimental field in Capão do Leão, RS, Brazil. The higher values of mean squares associated to GCA indicates a strong contribution of additive genetic effects to the expression of grain chemical components. The parents tested showed a tendency to develop progeny with negative heterosis regarding protein, lipid, β-glucan and soluble dietary fiber in the grain, and positive for the content of nitrogen-free extract, total and insoluble dietary fiber. IAC 7 features a potential parent for obtaining grains with high protein and dietary fiber content, and low caloric content, fit to human diet. Meanwhile, UPF 15 and FAPA Louise can represent donors of alleles to increase lipid contents, while FAPA Louise and URS Guapa can be used to raise the grain nitrogen-free extract contents of lines intended for animal feeding. [ABSTRACT FROM AUTHOR]

White oat genotypes were subjected to Al stress in hydroponic conditions in order to verify the viability of methods based on minimum nutrient solution (MNS) in comparison to complete nutrient solution (CNS), commonly used in the characterization and selection for Al tolerance in this species. The experimental design was completely randomized blocks with three replicates composed of 10 seedlings each. Six white oat genotypes subjected to different Al levels in minimum (0, 3, 6, and 9 mg L) and complete (0, 10, 20, and 30 mg L) solutions were evaluated. In this evaluation, the MNS was efficient in identifying aluminum-tolerant, white oat genotypes under hydroponics. The root growth resumption showed to be the most effective trait in the aluminum-tolerant plant selection. At concentrations equal to or higher than 3 mg Al L in minimum and 10 mg Al L in complete solution, severe damage caused by the toxic element on root development was verified. The white oat cultivars UFRGS 14, ALBASUL, and BARBARASUL showed aluminum tolerance in the tested conditions. [ABSTRACT FROM AUTHOR]

Fusarium head blight (FHB) is a destructive disease in wheat (Triticum aestivum) and other small grains. Morphological traits can act as barrier between pathogen and plant and provide a passive form of resistance to disease. The objectives were: (1) to phenotype 250 soft red winter wheat (SRWW) breeding lines and cultivars for morphological traits in 2015–2016; (2) to estimate their correlations with disease resistance; and (3) to identify QTL for morphological traits associated with FHB resistance through genome-wide association study (GWAS). Morphological traits measured were anther extrusion, plant height, peduncle length, spike length (SL), spikelet number (SN), spike density (SD), spike inclination (SI). Agronomic traits included heading date and yield. Disease traits were: FHB-rating, incidence, severity, FHB-index, Fusarium damaged kernels and deoxynivalenol (DON) concentration. There were significant (p < 0.01) differences among genotypes for all morphological traits measured. Moderate heritabilities (0.41–0.66) for spike traits were estimated. Morphological and disease traits were generally negatively correlated; e.g. there was a significant (p < 0.01) negative correlation between spike inclination and DON. GWAS identified 29 significant (p < 0.001) SNPs associated with morphological traits, ranging from − 3.54 to 9.58% of the trait mean. Potential SNPs for yield were located on chromosomes 1B, 3B and 6A. Despite the small effects identified for the SNPs, several morphological traits should be considered for phenotypic and/or genomic selection in FHB resistance breeding programs. [ABSTRACT FROM AUTHOR]