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'MN‐Torgy' (Reg. no. CV‐1203, PI 698205) hard red spring wheat (Triticum aestivium L.) was released by the University of Minnesota Agricultural Experiment Station in 2020 because of its high grain yield, disease resistance, and end‐use quality characteristics. MN‐Torgy is a medium‐maturity cultivar with above average plant height despite containing the semi‐dwarfing allele Rht24b. MN‐Torgy has moderate resistance to Fusarium head blight (caused primarily by Fusarium graminearum Schwabe) and good resistance to prevalent races of pathogens causing leaf rust (Puccinia triticina Eriks.) and stem rust (Puccinia graminis Pers.:Pers. f. sp. tritici Eriks. & E. Henn.) and is well adapted to the north‐central United States. MN‐Torgy also has good adult plant resistance to the Ug99 family of stem rust races. Core Ideas: MN‐Torgy is a new hard red spring wheat cultivar.MN‐Torgy spring wheat has field resistance to the Ug99 family of stem rust races.MN‐Torgy spring wheat is moderately resistant to Fusarium head blight. [ABSTRACT FROM AUTHOR]

Fusarium head blight continues to be a threat to spring wheat (Triticum aestivum L.) production in the north‐central region of the United States. 'Lang‐MN' (Reg. no. CV‐1182, PI 687038) hard red spring wheat was released by the University of Minnesota Agricultural Experiment Station in 2017 because it combines the best available Fusarium head blight resistance with high grain yield, grain protein concentration, and good end‐use quality characteristics. Lang‐MN is a mid‐late maturity cultivar that also has acceptable lodging resistance despite its above average plant height owing to its lack of the semi‐dwarfing genes Rht‐B1 or Rht‐D1 but presence of Rht24. Lang‐MN has good resistance to the prevalent races of leaf rust, stripe rust, and stem rust and is well adapted to the north‐central United States. [ABSTRACT FROM AUTHOR]

Fusarium culmorum (Fc) and F. graminearum (Fg) belong to the predominant causal agents of fusarium crown and root rot (FCR) in wheat. While many studies have been done to investigate crown rot, including stem base infection, root colonization and mycotoxin production associated with root rot is not well understood. In this study the impact of mycotoxins on the colonization of wheat roots and stem bases was analysed by using Fc and Fg isolates that varied in both quantity and types of trichothecenes they produce. Seedling inoculations in growth chambers with a high deoxynivalenol (DON)‐ and 3‐acetyldeoxynivalenol (3ADON)‐producing isolate led to more severe symptoms and 20‐times greater colonization of the stem base, as measured by Fc DNA accumulation, than isolates that produced less DON/3ADON. In contrast to stem base colonization, in vitro inoculations of roots with a Tri5 deletion mutant deficient in Fg trichothecene production led to three‐times higher colonization than the wildtype. Furthermore, an Fc isolate that produced low levels of zearalenone resulted in twice the level of colonization of a high DON/3ADON‐producing isolate included in the study. When root inoculation with a low DON/3ADON‐producing Fc isolate was supplemented with exogenous DON, DON production decreased by more than half per unit weight of Fc DNA, and root colonization doubled compared to the untreated control. Therefore, in contrast to its potential role as an aggressiveness factor in stem base infection, trichothecene production by Fc and Fg is detrimental to the early stages of wheat root colonization in FCR. [ABSTRACT FROM AUTHOR]

Utilization of quantitative trait loci (QTL) identified in bi-parental mapping populations has had limited success for improving complex quantitative traits with low to moderate heritability. Association mapping in contemporary breeding germplasm may lead to more effective marker strategies for crop improvement. To test this approach, we conducted association mapping of two complex traits with moderate heritability; Fusarium head blight (FHB) severity and the grain concentration of mycotoxin associated with disease, deoxynivalenol (DON). To map FHB resistance in barley, 768 breeding lines were evaluated in 2006 and 2007 in four locations. All lines were genotyped with 1,536 SNP markers and QTL were mapped using a mixed model that accounts for relatedness among lines. Average linkage disequilibrium within the breeding germplasm extended beyond 4 cM. Four QTL were identified for FHB severity and eight QTL were identified for the DON concentration in two independent sets of breeding lines. The QTL effects were small, explaining 1-3% of the phenotypic variation, as might be expected for complex polygenic traits. We show that using breeding germplasm to map QTL can complement bi-parental mapping studies by providing independent validation, mapping QTL with more precision, resolving questions of linkage and pleiotropy, and identifying genetic markers that can be applied immediately in crop improvement. [ABSTRACT FROM AUTHOR]

The development of wheat (Triticum aestivum L.) cultivars resistant to Fusarium head blight (FHB) (caused by Fusarium graminearum Schwabe) requires screening methodologies that accurately characterize reaction to this disease. The objectives of this study were (i) to characterize the stability of cultivars for their FFB reaction and (ii) to define an optimum resource allocation for FHB evaluation. Fourteen cultivars were evaluated in FHB-screening nurseries at two locations across a 4-yr period. Field data were used to calculate disease incidence (INC) as the frequency of symptomatic spikes and disease index (DIS) as the mean disease score of all spikes. FHR reaction also was evaluated on harvested grain as percent visually scabby kernels (VSK) and deoxynivalenol (DON) concentration. Significant differences among cultivars for all FLIB parameters were found in each environment. Pearson correlation coefficients among FHB parameters were positive and highly significant, ranging from 032 between INC and DON to 0.72 between INC and DIS. Spearman rank correlation coefficients for yearly cultivar rankings and Kendall's coefficient of concordance were high, indicating similarity of the rankings of the tested cultivars in different environments. Visually scabby kernels was the DIS parameter with highest similarity for cultivar ranking across environments. Most of the cultivars, including susceptible ones, expressed stability for FUR reaction. Optimum resource allocation for DIS was most affected by the number of environments with three being the minimum to accurately characterize a genotype's resistance level. Using more than three replications or scoring more than 10 spikes per plot had little practical value in characterizing FHB reaction. [ABSTRACT FROM AUTHOR]

Relates the percent of Amelanchier alnifolia, commonly known as saskatoon leaf area infected to the relative concentration of Entomosporium mespili conidia released from the infected tissue and the development of a regression equation for the relationship. Identification when the E.mespili conidia are released in relation to prevailing environmental conditions during the growing season; Determination whether the amount of conidia released is related to the amount of rainfall during precipitation events.

Fusarium head blight (FHB) is a disease problem (primarily caused by Fusarium graminearum Schwabe) that affects the quality and yield of barley (Hordeum vulgare L.) grain. The objectives of this study were to identify the location of quantitative trait loci (QTL) for resistance to FHB in a two-rowed by six-rowed population, to examine the association of FHB resistance with heading date and the Vrs1 (two-rowed spike morphology) locus, to validate the location of the major FHB resistance QTL primarily detected in the field, and to identify simple sequence repeat (SSR) markers linked to the QTL for FHB resistance. We created a genetic map of 143 molcular markers from a population derived from the parents Fredrickson (two-rowed, moderately resistant) and Stander (six-rowed, susceptible). The Fredrickson/Stander population was evaluated in two field environments by a grain spawn inoculation method, two field environments by a spray inoculation, and two greenhouse environments. QTL analysis detected three distinct regions on chromosome 2(2H) associated with FHB resistance; two of these regions were also associated with resistance to deoxynivalenol (DON) accumulation. One FHB resistance QTL was also associated with heading date, while another FHB resistance QTL was found associated with the Vrs1 locus. The third FHB resistance QTL was detected only in the greenhouse, but was coincident with a QTL for resistance to DON accumulation in the field. All three QTL were detected in the greenhouse, indicating that this environment may be useful for selecting FHB resistant barley genotypes. SSR markers were identified that are linked with each QTL and could prove useful for marker-assisted trait manipulation. Finally, the two major QTL detected in the field were validated using an independent population with Fredrickson and Stander parents. [ABSTRACT FROM AUTHOR]

Fusarium head blight occurs in cereals throughout the world and is especially important in humid growing regions. Fusarium head blight (FHB) has re-emerged as a major disease of wheat and barley in the U.S. and Canada since 1993. The primary causal agents of FHB, Fusarium graminearum and Fusarium culmorum, can produce deoxynivalenol (DON), a trichothecene mycotoxin that enhances disease severity and poses a health hazard to humans and monogastric animals. To reduce the effects of DON on wheat, we have introduced FsTRI101, a Fusarium sporotrichioides gene formerly known as TriR, into the regenerable cultivar Bobwhite. TRI101 encodes an enzyme that transfers an acetyl moiety to the C3 hydroxyl group of trichothecenes. Four different transgenic plants carrying the FsTRI101 gene were identified. Although expression levels varied among the four lines, all of them accumulated FsTRI101 transcripts in endosperm and glume. TRI101-encoded acetyltransferase activity was detected in endosperm extracts of a single plant that accumulated FsTRI101 mRNA. Greenhouse resistance tests indicated that the accumulation of FsTRI101-encoded acetyltransferase in this plant confers partial protection against the spread of F. graminearum in inoculated wheat heads (spikes). [ABSTRACT FROM AUTHOR]

Resistance to Fusarium head blight (FHB), deoxynivalenol (DON) accumulation, and kernel discoloration (KD) in barley are difficult traits to introgress into elite varieties because current screening methods are laborious and disease levels are strongly influenced by environment. To improve breeding strategies directed toward enhancing these traits, we identified genomic regions containing quantitative trait loci (QTLs) associated with resistance to FHB, DON accumulation, and KD in a breeding population of F4:7 lines using restriction fragment length polymorphic (RFLP) markers. We evaluated 101 F4:7 lines, derived from a cross between the cultivar Chevron and an elite breeding line, M69, for each of the traits in three or four environments. We used 94 previously mapped RFLP markers to create a linkage map. Using composite interval mapping, we identified 10, 11, and 4 QTLs associated with resistance to FHB, DON accumulation, and KD, respectively. Markers flanking these QTLs should be useful for introgressing resistance to FHB, DON accumulation, and KD into elite barley cultivars. [ABSTRACT FROM AUTHOR]

Anther culture and maize hybridization are two frequently used techniques for doubled haploid production in wheat ( Triticum aestivum L.). Information on the field performance of lines derived from these techniques is limited. This study was conducted to compare the performance of F4:6 lines obtained by single-seed descent with lines obtained by anther culture and maize ( Zea mays L.) pollination from the same cross of spring wheat, ’Chris’/MN 7529. Thirty-three lines derived from each of those techniques were evaluated in six environments for grain yield, protein content, test weight, heading date, kernel weight and plant height. Mean performance of the single-seed descent lines exceeded performance of the anther culture lines for grain yield, kernel weight and plant height with no apparent differences for grain protein content, test weight and heading date. No differences between trait means for the single-seed descent and maize pollination lines were found except for plant height. The best 5 lines from each method for grain yield, protein content and test weight were similar in performance except that the protein content was higher for the maize pollination lines than for the single-seed descent lines. Acceptable levels of agronomic performance could be found among lines from each method. Wide acceptance of the doubled haploid technique for pure line production in breeding programs may, however, be limited by the often poor efficiency of doubled haploid line production, resulting in smaller population sizes for selection of desirable traits in comparison to the single-seed descent method. [ABSTRACT FROM AUTHOR]

The article offers information the registration of Ada hard red spring wheat cultivar, which was developed and released by the Minnesota Agricultural Experiment Station together with the U.S. Department of Agriculture's (USDA) Agricultural Research Service. High grain yield and protein content, leaf rust resistance, and straw strength were among the basis used in releasing Ada. The bread making properties of Ada were also evaluated by the USDA Spring Wheat Quality Laboratory. Information about the loaf, grain, and protein volume of the wheat were also provided.

Introduces the 'Oklee' wheat, a hard red spring wheat. Derivation of the Oklee wheat; Description on the physical aspect of the wheat; Result of the evaluation of bread-making properties of Oklee grown conducted by the USDA Spring Wheat Quality Laboratory, Fargo, ND.

Focuses on the registration of Lacey, a spring barley. Development of barley by Minnesota Agricultural Experiment Station; Purpose of development; Application of pedigree method with single-seed descent; Replacement of Robust varieties; Quality of the barley; Comparison between Lacey and Robust.