1,721,094 research outputs found
Registration of ‘Drummond’ barley
No full textSteffenson, Brian; Horsley, R.D.; Franckowiak, J.D.; Schwarz, P.B.. (2002). Registration of ‘Drummond’ barley. Retrieved from the University Digital Conservancy, https://hdl.handle.net/11299/188611
Registration of ‘Foster’ barley
Full text linkSteffenson, Brian; Horsley, R.D.; Franckowiak, J.D.; Schwarz, P.B.. (1997). Registration of ‘Foster’ barley. Retrieved from the University Digital Conservancy, 0011-183X
Identification of Cochliobolus sativus isolates expressing differential virulence on two-rowed barley genotypes from North Dakota
Full text linkCanadian Journal of Plant Pathology website: http://www.tandfonline.com/loi/tcjp20Severe spot blotch infection was observed in 1990 on several two-row barley breeding lines previously regarded as resistant to
Cochliobolus sativus. Studies were conducted to compare the virulence pattern of a C. sativus isolate (ND90Pr) obtained from
this two-row breeding nursery with one (ND85F) used in previous disease screening evaluations. Greenhouse and field experiments
were performed in 1991 and 1992 at Fargo, ND, using a split plot design with isolate as the main effect. Isolates ND90Pr
and ND85F exhibited distinct differential virulence patterns on barley genotypes ND 5883, ND 12437, ND 12720, ND 12721,
and Bowman. Isolate ND90Pr displayed high virulence on ND 12720, ND 12721, and Bowman, and low virulence on ND 5883
and ND 12437. In contrast, isolate ND85F was highly virulent on ND 5883 and ND 12437 and weakly virulent on ND 12720,
ND 12721, and Bowman. Both isolates expressed low virulence on genotype ND Bl 12, the primary source of resistance to C.
sativus in commercial six-row barley germplasm. To incorporate adequate levels of resistance into future two-row barley cultivars,
disease evaluations should be made with C. sativus isolates that express the full spectrum of virulence found in North
Dakota.Fetch Jr, T.G.; Steffenson, Brian. (2009). Identification of Cochliobolus sativus isolates expressing differential virulence on two-rowed barley genotypes from North Dakota. Retrieved from the University Digital Conservancy, 10.1080/07060669409500754
Reaction of barley seedlings with different stem rust resistance genes to Puccinia graminis f. sp. tritici and P. g. f. sp. secalis
No full textCanadian Journal of Plant Pathology website: http://www.tandfonline.com/loi/tcjp20Seedling tests are desirable for disease resistance screening in breeding programs because a large number of lines can be evaluated in a short period of time and with modest space requirements. This study was undertaken to identify pathotypes of the wheat stem rust pathogen (Puccinia graminis f. sp. tritici) and cultures of the rye stem rust pathogen (Puccinia graminis f. sp. secalis) that might be useful for detecting resistance genes in barley (Hordeum vulgare) at the seedling stage. Barley accessions with different resistance genes (Rpg1, Rpg2, Rpg3, rpg4, and rpgBH) were assessed for their infection types (ITs) to 13 pathotypes of P. graminis f. sp. tritici and two cultures of P. graminis f. sp. secalis at two temperature regimes (18–21 °C and 24–25 °C). The P. graminis f. sp. tritici pathotypes HKHJ and QCCJ were effective for specifically detecting Rpg1 and rpg4, respectively, and will facilitate resistance breeding efforts. No cultures were found to be effective for specifically detecting the resistance of Hietpas-5, PI 382313, or Black Hulless at the seedling stage. Some pathotypes or cultures did, however, produce low ITs on these sources and will therefore be useful for genetic studies involving crosses with susceptible barleysSun, Y; Steffenson, Brian. (2005). Reaction of barley seedlings with different stem rust resistance genes to Puccinia graminis f. sp. tritici and P. g. f. sp. secalis. Retrieved from the University Digital Conservancy, http://dx.doi.org/10.1080/07060660509507198
Two genomic regions contribute disproportionately to geographic differentiation in wild barley
Full text linkGenetic differentiation in natural populations is driven by geographic distance and by
ecological or physical features within and between natural habitats that reduce migration. The primary
population structure in wild barley differentiates populations east and west of the Zagros Mountains.
Genetic differentiation between eastern and western populations is uneven across the genome and is
greatest on linkage groups 2H and 5H. Genetic markers in these two regions demonstrate the largest
difference in frequency between the primary populations and have the highest informativeness for
assignment to each population. Previous cytological and genetic studies suggest there are chromosomal
structural rearrangements (inversions or translocations) in these genomic regions. Environmental association
analyses identified an association with both temperature and precipitation variables on 2H and with
precipitation variables on 5H.Fang, Zhou; Gonzales, Ana M; Clegg, Michael T; Smith, Keven P; Muehlbauer, Gary J; Steffenson, Brian; Morrell, Peter L. (2014). Two genomic regions contribute disproportionately to geographic differentiation in wild barley. Retrieved from the University Digital Conservancy, https://doi.org/10.1534/g3.114.010561
Effect of incubation time and temperature on the phenotypic expression of rpg4 to Puccinia graminis f. sp. tritici in barley
Full text linkCanadian Journal of Plant Pathology website: http://www.tandfonline.com/loi/tcjp20To study the effect of incubation time and temperature on the phenotypic expression of rpg4, five barley genotypes with this
resistance gene were infected with pathotype QCCJ of Puccinia graminis f. sp. tritici at the seedling stage, then subjected to various
times of incubation at either 18-19°C or 27~28°C. Genotypes with rpg4 exhibited low (0, 0;, and 1), mesothetic (e.g.
3-210;, 120;3), and high (3,3) infection types at 18-19°C after initial incubation at 27-28°C for 0-28, 40-76, and 88 or more
hours, respectively. A period of 88 or more hours of initial incubation at high temperature rendered the rpg4 resistance completely
ineffective against this pathotype of P. g. f. sp. tritici. In contrast, high, mesothetic, and low infection types were found
for the same genotypes at 27-28°C after initial incubation at 18-19°C for 0-40, 52-100, and 112 or more hours, respectively.
The resistant infection types conferred by rpg4 are apparently established within the first 112 hours after the end of the infection
period since subsequent shifts to higher temperature did not result in marked changes in the resistance response. These data indicate
the critical importance of maintaining precise temperature control when assessing the infection phenotypes of barley genotypes
carrying the stem rust resistance gene rpg4.Sun, Yonglian; Steffenson, Brian. (1997). Effect of incubation time and temperature on the phenotypic expression of rpg4 to Puccinia graminis f. sp. tritici in barley. Retrieved from the University Digital Conservancy, http://dx.doi.org/10.1080/07060669709500567
Sources of resistance to septoria speckled leaf blotch caused by Septoria passernii in barley
No full textCanadian Journal of Plant Pathology website: http://www.tandfonline.com/loi/tcjp20Septoria speckled leaf blotch (SSLB), incited by Septoria passerinii, has reemerged as one of the most serious foliar diseases of barley (Hordeum vulgare) in the Upper Midwest region of the United States over the last decade. The most cost-effective and environmentally safe method of preventing SSLB epidemics is through the use of resistant cultivars. Thus, the objective of this study was to investigate sources of resistance to S. passerinii in barley and to determine the reliability of greenhouse seedling tests for predicting the adult-plant reaction in the field. From a preliminary greenhouse screening of over 250 barley accessions, 78 lines were selected and subsequently evaluated at the seedling (greenhouse) and adult-plant (field) stages for reaction to S. passerinii. All of the major malting (H. vulgare ‘Drummond’, ‘Excel’, ‘Foster’, ‘Lacey’, ‘Legacy’, ‘Morex’, ‘Stander’, ‘Conlon’, and ‘Robust’) and feed (H. vulgare ‘Bowman’, ‘Logan’, and ‘Royal’) cultivars grown in or recommended for the Upper Midwest region of the United States were highly susceptible. Highly significant correlations were detected between the infection response of seedlings in the greenhouse and adult plants in the field. Twenty-nine accessions exhibited resistance at both the seedling and adult-plant stages. The resistant accessions identified in this study were from geographically diverse regions and will be valuable in developing barley cultivars with diverse and broad-based resistance to SSLB.Toubia-Rahme, H; Steffenson, Brian. (2004). Sources of resistance to septoria speckled leaf blotch caused by Septoria passernii in barley. Retrieved from the University Digital Conservancy, http://dx.doi.org/10.1080/07060660409507153
A resistance gene to Ustilago nuda in barley is located on chromosome 3H
Full text linkCanadian Journal of Plant Pathology website: http://www.tandfonline.com/loi/tcjp20Loose smut of barley is a common disease which can be controlled using resistant varieties. Information on the chromosome location of loci controlling loose smut resistance and the development of molecular markers to aid in selection for these genes can be beneficial in the resistant variety development process. The objectives of this work were to determine the resistance or susceptibility of doubled haploid barley lines arising from a cross of the varieties ‘Steptoe’ and ‘Morex’ to Ustilago nuda, the causal agent of loose smut of barley, and map the chromosome location of the loose smut resistance locus in ‘Morex’. The reaction to Ustilago nuda of the doubled-haploid barley plants was determined by inoculating spikelets of each line at anthesis by injection of a teliospore suspension using a needle inoculation method. Mature seeds from the inoculated spikelets were grown to determine the percentage of plants that developed with smutted heads. The lines were classified as susceptible if greater than 10% of the plants were smutted. The loose smut resistance locus from the resistant source ‘Morex’ was mapped using an existing DNA marker map of the ‘Steptoe’/‘Morex’ population. The distribution of the resistant and susceptible progeny from the loose smut testing fit a single gene model. The resistance gene was mapped to chromosome 3 (3H).Menzies, J.G; Steffenson, Brian; Kleinhofs, A. (2010). A resistance gene to Ustilago nuda in barley is located on chromosome 3H. Retrieved from the University Digital Conservancy, http://dx.doi.org/10.1080/07060661003739977
The rpg4/Rpg5 stem rust resistance locus in barley; resistance genes and cytoskeleton dynamics
Full text linkTwo closely linked resistance genes, rpg4 and Rpg5, conferring resistance to several races of Puccinia graminis, were cloned and characterized. The Rpg5 gene confers resistance to an isolate of Puccinia graminis f. sp. secalis (Pgs), while rpg4 confers resistance to Puccinia graminis f. sp. tritici (Pgt). Rpg5 is a novel gene containing nucleotide binding site-leucine rich repeat domains in combination with a serine threonine protein kinase domain. High-resolution mapping plus allele and recombinant sequencing identified the rpg4 gene, which encodes an actin depolymerizing factor-like protein (ADF2). Resistance against the Pgt races QCCJ, MCCF, TTKSK (aka Ug99) and RCRS requires both Rpg5 and rpg4, while Rpg5 alone confers resistance to Pgs isolate 92-MN-90. The dependency on the actin modifying protein ADF2 indicates cytoskeleton reorganization or redirection plays a role in pathogen-host interactions. Rpg5 may interact with ADF2 to activate or deactivate its function in the resistance response. Alternatively, Rpg5 could initiate signal transduction leading to resistance in response to detecting ADF2 protein modification. Pgt may redirect the actin cytoskeleton by inducing modifications of ADF2. The redirection of actin could possibly enable the pathogen to develop a haustoria-plant cell cytoskeleton interface for acquisition of nutrients.Brueggeman, Robert; Steffenson, Brian; Kleinhofs, Andris. (2009). The rpg4/Rpg5 stem rust resistance locus in barley; resistance genes and cytoskeleton dynamics. Retrieved from the University Digital Conservancy, http://dx.doi.org/10.4161/cc.8.7.8079
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