bluuebunny/crossref_metadata_2025_split huggingface dataset:
New and Diverse Sources of Multiple Disease Resistance in Wheat
Authors: Gurung Suraj , Bonman J. Michael , Ali Shaukat , Patel Jaimin , Myrfield Mary , Mergoum Mohamed , Singh Pawan K. , Adhikari Tika B. 
Published: August 2009

ABSTRACTTan spot (caused by Pyrenophora tritici‐repentis) and Stagonospora nodorum blotch (SNB), (caused by Phaeosphaeria nodorum) are destructive diseases of wheat (Triticum aestivum L.). The majority of currently grown wheat varieties are susceptible to both diseases, presumably because of high pathogenic variability occurring in these fungi or narrow genetic background for resistance in wheat varieties. Therefore, identifying new sources of tan spot and SNB resistance in wheat is imperative. A subset of 825 wheat accessions from the core collection of the National Small Grains Collection (NSGC) of the United States Department of Agriculture, National Plant Germplasm System (NPGS) was evaluated for resistance to tan spot and SNB at seedling stage in a growth chamber. On the basis of disease reactions, 88 wheat accessions exhibited resistance to both diseases. Data from the Germplasm Resources Information Network (GRIN) were examined for the 88 accessions to identify those that also have resistance to other key diseases and on this basis 28 accessions with multiple resistances were identified. The genetic relationship among the 88 accessions was assessed using resistance gene analog polymorphism (RGAP) primers. Wheat accessions with similar growth habit were grouped together despite differences in country of origin. Associations between agronomic traits and host resistance indicated that winter wheat habit in the studied collection was strongly associated with both SNB and tan spot resistance. This study identified genetically diverse wheat accessions with broad‐spectrum resistance that can be used in developing cultivars with high levels of resistance to multiple diseases in wheat breeding programs.
Identification of QTL Conferring Resistance to Fusarium Head Blight Resistance in the Breeding Line C93‐3230‐24
Authors: Lamb Kenneth E. , Gonzalez‐Hernandez Jose L. , Zhang Bingxin , Green Marci , Neate Stephen M. , Schwarz Paul B. , Horsley Richard D. 
Published: August 2009

ABSTRACTControl of Fusarium head blight (FHB), incited primarily by Fusarium graminearum Schwabe [telomorph Gibberella zea (Schwein)], has been a challenge for barley (Hordeum vulgare L.) producers in the upper midwestern United States for more than a decade. This disease manifests primarily in the form of food safety issues and quality discounts due to the presence of deoxynivalenol (DON), a mycotoxin produced by the pathogen. Cultural practices and fungicides only provide partial control; genetic resistance to FHB and DON accumulation may add to control of the disease. Field studies in North Dakota and China were conducted in FHB disease nurseries using 118 double‐haploid lines from the cross C93‐3230‐24/‘Foster’. Foster is susceptible to FHB, and C93‐3230‐24 is moderately resistant. The quantitative trait locus (QTL) analysis revealed five putative QTL for Type I FHB resistance; however, only the one in bins 7 and 8 of chromosome 2H was detected in more than 70% of the environments. In addition, QTL associated with late days to heading and maturity and tall plant height also were located in the same region. Three putative QTL for increased DON accumulation were detected; however, none were detected in more than three of the eight environments where data were collected. On the basis of these results, it is unlikely that C93‐3230‐24 has a novel QTL for FHB resistance different from those identified in other resistant accessions. However, C93‐3230‐24 is unique in that it provides QTL for improved FHB resistance but not reduced DON accumulation. This is an atypical response compared with other sources of FHB resistance and provides evidence that FHB resistance and DON accumulation are under separate genetic control.
Yield and Water Use Response of Cuphea to Irrigation in the Northern Corn Belt
Authors: Gesch R. W. , Sharratt B. S. , Kim K.‐I. 
Published: August 2009

ABSTRACTCuphea (Cuphea viscosissimaJacq. ×C. lanceolataW.T. Aiton) may be prone to drought stress, yet little is known about the yield response of this new oilseed crop to irrigation. A field study was conducted in western Minnesota on a Barnes loam soil (fine‐loamy, mixed, superactive, frigid Calcic Hapludolls) in 2002 and 2003 to compare yield and water use of irrigated and nonirrigated cuphea. Nonirrigated cuphea received only precipitation, while irrigated plants received supplemental watering to maintain soil water content near field capacity during the study. Crop drought stress was assessed by measuring photosynthesis, stomatal conductance, leaf water potential, and δ13C (13C/12C stable isotope composition). In 2002, soil water content was similar for irrigated and nonirrigated plants throughout the growing season owing to timely rains, and seed yield was similar between treatments (873 kg ha−1). During 2003, irrigation resulted in a 2.7‐fold increase in seed yield and greater harvest index than nonirrigated plants, while water use efficiency (WUE) of seed production for both treatments was similar (2.4 kg ha−1mm−1). Drought conditions occurred in 2003; by mid‐August, leaf photosynthesis and leaf water potential of nonirrigated plants were 83 and 56% less, respectively, than for irrigated cuphea. Moreover, δ13C measurements of seed further confirmed that nonirrigated cuphea suffered significant drought stress. Our results indicate that cuphea is drought sensitive and that regions or soils prone to water deficits will likely require supplemental irrigation to increase seed yield.
Biplot Analysis of Genotype × Environment Interaction: Proceed with Caution
Authors: Yang Rong‐Cai , Crossa Jose , Cornelius Paul L. , Burgueño Juan 
Published: August 2009

ABSTRACTBiplot analysis has been used for studying genotype × environment interaction (GE) or any two‐way table. Its descriptive and visualization capabilities along with the availability of user‐friendly software have enabled plant scientists to examine any two‐way data by a click on a computer button. Despite widespread use, the validity and limitations of biplot analysis have not been completely examined. Here we identify and briefly discuss six key issues surrounding overutilization or abuse of biplot analysis. We question (i) whether the retention of the first two multiplicative terms in the biplot analyses is adequate; (ii) whether the biplot can be more than a simple descriptive technique; (iii) how realistic a “which‐won‐where” pattern is identified from a biplot; (iv) what if genotypes and/or environments are random effects; (v) how relevant biplot analysis is to the understanding of the nature and causes of interaction; and (vi) how much the biplot analysis can contribute to detection of crossover interaction. We stress the need for use of confidence regions for individual genotype and environment scores in biplots to make critical decisions on genotype selection or cultivar recommendation based on a statistical test. We conclude that the biplot analysis is simply a visually descriptive statistical tool and researchers should proceed with caution if using biplot analysis beyond this simple function.
DNA Polymorphisms of Genes Involved in Fiber Development in a Selected Set of Cultivated Tetraploid Cotton
Authors: Lu Yingzhi , Curtiss Jessica , Percy R. G. , Hughs S. E. , Yu Shuxun , Zhang Jinfa 
Published: August 2009

ABSTRACTThe lack of genetic diversity within cultivated upland cotton (Gossypium hirsutum L.) has hindered the construction of genomewide linkage maps and their applications in genetics and breeding. The objective of this investigation was to develop candidate gene markers for fiber quality and yield on the basis of approximately 90 genes implicated in fiber development. Polymorphisms using sequence‐tagged site (STS) and single nucleotide polymorphism (SNP) markers based on single strand conformation polymorphism (SSCP) and cleaved amplified polymorphism (CAP) were evaluated among three upland and five Pima cotton (G. barbadense L.) genotypes. Of the 90 primer pairs, 75 resulted in polymerase chain reaction amplifications, including 11 that yielded polymorphic STS markers. Of the 48 primer pairs that produced polymorphic SSCP markers, 27 yielded interspecific polymorphism, while 15 yielded both inter‐ and intraspecific polymorphisms. Six pairs yielded only intraspecific polymorphisms. A total of 18 SNPs, including four indels, were identified in seven of the 15 fiber gene fragments on the basis of direct DNA sequencing, and the average length was 350 bp, with a mean of 1.3 SNPs per fragment. The average rate of SNPs per nucleotide was 0.34%, and 0.31% and 0.41% in coding and noncoding regions, respectively. Eight of the 15 SNPs were interspecific and 78% were nucleotide substitutions, with the four indels contributing to interspecific polymorphism. Six selected SNPs were confirmed by restriction enzyme digestion. The high level of SSCP polymorphism observed within a selected set of agronomically improved lines of upland cotton suggests that the use of SSCP will greatly facilitate genomewide mapping in upland cotton.
Photosynthetic Responses of Bermudagrass to Drought Stress Associated with Stomatal and Metabolic Limitations
Authors: Hu Longxing , Wang Zhaolong , Huang Bingru 
Published: August 2009

ABSTRACTPlants may survive drought stress by altering photosynthetic metabolism. This study was designed to investigate stomatal and metabolic changes associated with photosynthetic responses to drought for bermudagrass. A hybrid bermudagrass [Cynodon dactylon (L.) Pers. × C. transvaalensis Burtt Davy, cv. Tifway] and a common bermudagrass (C. dactylon, cv. C299) were subjected to drought by withholding irrigation in growth chambers. Tifway maintained higher relative water content and lower electrolyte leakage than C299 under drought. Net photosynthetic rate (Pn) and stomatal conductance (gs) decreased, with more rapid decline in C299, but Pn was significantly greater in Tifway than in C299, while gs did not differ between the two genotypes during 14 d of drought. Photochemical efficiency, ribulose‐1,5‐bisphosphate carboxylase:oxygenase (Rubisco) activity, and activation state declined during drought stress, but were higher in Tifway than in C299 within 14 d of treatment. Electrophoretic analysis revealed that at 14 and 18 d of drought, pyruvate orthophosphate dikinase (98 kDa) and Rubisco protein (49 kDa) exhibited severe degradation in C299 but to a lesser extent in Tifway. These results indicated that the superior drought resistance in Tifway could be attributed to higher photosynthetic capacity through the maintenance of higher metabolic activities, as manifested by more active Rubisco enzyme and Rubisco activase and more stable photosynthetic proteins.
Sources of Soybean Rust Resistance Challenged with Single‐Spored Isolates of Phakopsora pachyrhizi
Authors: Paul C. , Hartman G. L. 
Published: August 2009

ABSTRACTSoybean rust, caused by the fungus Phakopsora pachyrhizi Syd., is a potentially devastating disease that can cause significant yield losses. Resistance in soybean [Glycine max (L.) Merr.] germplasm, both qualitative and quantitative, may be effective in providing at least partial control of soybean rust. A number of soybean genotypes have resistance to soybean rust, but few of these have been challenged with the recently recovered U.S. isolates. The objective of this study was to evaluate known sources of soybean rust resistance against U.S. isolates of P. pachyrhizi Twenty‐eight soybean genotypes that either contained known major‐genes for resistance or had been reported as new sources of soybean rust resistance, along with two susceptible checks, were challenged with six P. pachyrhizi isolates collected in the U.S. All six isolates produced similar phenotypic reactions within each of the genotypes. Five genotypes, including the Rpp1 source and the isoline of ‘Williams 82’ with Rpp1, had no visible lesions. Eleven genotypes produced red‐brown lesions with few uredinia, including the sources of Rpp2 and Rpp3, and the remainder had susceptible tan lesions, including the source of resistance for Rpp4 Uredinial counts from genotypes producing red‐brown lesions on live and fixed leaflets showed significant variation in the number of uredinia with a genotype × isolate interaction. Uredinial counts from genotypes producing tan lesions on live and fixed leaflets showed significant variation in the number of uredinia among genotypes, but there was no genotype × isolate interaction. There were significant correlations (r = 0.8, P < 0.0001; and r = 0.4, P < 0.0001) between uredinial counts based on live and fixed leaflets within genotypes producing red‐brown lesions and those producing tan lesions, respectively.
Rapid Microwave Processing of Winter Cereals for Histology Allows Identification of Separate Zones of Freezing Injury in the Crown
Authors: Livingston D. P. , Tuong T. D. , Haigler C. H. , Avci U. , Tallury S. P. 
Published: August 2009

ABSTRACTIn histological studies, microwave processing of tissue considerably shortens the time required to prepare samples for observation under light and electron microscopy. However, plant tissues from different species and different regions of the plant respond differently to microwave processing, making it impossible to use a single protocol for all plant tissue. The crown of winter cereals such as rye (Secale cereale L.), wheat (Triticum aestivum L.), barley (Hordeum vulgare L.), and oats (Avena sativa L.) is the below‐ground portion of the stem that overwinters. It is composed of numerous types of cells with an organizational pattern that is similar to other grasses. When we used microwave protocols that were developed for other plant tissues, winter cereal crown tissue shattered and crumbled when sectioned. This study reports a procedure developed to process winter cereal crowns for histological observations. Using this microwave protocol, samples were prepared in 1 d as compared to 2 wk using traditional protocols. This enabled many more samples to be processed and allowed us to identify four overlapping zones of response to freezing within the crown. Results of varying time, temperature, and microwave wattage during fixing, dehydrating, and embedding in paraffin are described. High quality sections from the crowns of oat, barley, wheat, and rye indicate that this procedure is valid for all winter cereals. Since crown tissue is similar across all grass species, we predict that the protocol will be useful for other grasses as well.
Quantitative 3D characterisation of graphite morphology in cast iron – correlation between processing, microstructure and properties
Authors: Velichko Alexandra , Mücklich Frank 
Published: August 2009

Abstract
Cast irons with different graphite morphologies were thoroughly analysed and their influence on the electrical properties was studied. Graphite morphology was analysed with focused ion beam tomography. The graphite crystal structure, nucleation and growth mechanisms were studied using chemical analysis and thin foils observations with transmission electron microscopy. Quantitative three-dimensional characterisation of the shape and spatial connectivity, as well as the growth mechanisms provided understanding of the structure of the different graphite morphologies and allowed the estimation of their influence on the effective properties using simulations directly on the tomographic data. First correlations between manufacturing parameters, spatial microstructure and effective properties were suggested for advanced material development and non-destructive quality control.
Structure, stresses and stress relaxation of TiN/Cu multilayer and nanocomposite coatings
Authors: Köstenbauer Harald , Hofer Anna M. , Fontalvo Gerardo A. , Keckes Jozef , Mitterer Christian 
Published: August 2009

AbstractStructural evolution, residual stresses, and stress relaxation at elevated temperatures were investigated for sputtered TiN/Cu multilayer films with a bilayer thickness between 100 and 800 nm, as well as nanocomposite films with a Cu content up to 30 at.%, to illuminate the effect of adding a soft metal to a hard nitride. In the nanocomposites the Cu domain size increases with rising Cu content from 7 to 22 nm at the expense of the TiN grain size, while it is strongly related to the bilayer thickness in the multilayers at constant TiN domain size. Films were thermally cycled in vacuum from room temperature up to 650 °C. Stresses during heating are governed by thermo-elastic behaviour and at temperatures above 300 °C by plastic deformation of the Cu phase and stress relaxation of both Cu and TiN, whereas the cooling phase is determined by thermo-elasticity, plastic deformation of the Cu phase and eventually tensile crack formation.
Surface modifications and their effect on the nickel release rate in nickel–titanium shape memory alloys
Authors: Heßing Christian , Pohl Michael 
Published: August 2009

Abstract
Several means of modifying surfaces of nickel – titanium have been investigated to gather information on how topography and the nickel release rates can be influenced. Electrolytically etched nickel – titanium surfaces show a very fine structure but show the highest nickel release of all modified surfaces. Electropolishing reduces the initial roughness of the material and lowers the Ni release due to very thick oxide films emerging in the course of the process of electropolishing. Further enhancement of the oxide layer can be achieved by oxidation in dry air or in a selectively oxidising atmosphere. Selectively oxidised samples exhibit the smallest Ni release of all modified surfaces.
Technology and mechanical properties of advanced γ-TiAl based alloys
Authors: Wallgram Wilfried , Schmölzer Thomas , Cha Limei , Das Gopal , Güther Volker , Clemens Helmut 
Published: August 2009

Abstract
The present paper summarizes our progress in establishing a novel production technology for -TiAl components to be used in advanced aircraft engines. In the beginning the main emphasis is put on the design of a -TiAl based alloy which exhibits excellent hot-workability. Then, the development of a “near conventional” hot-die forging route for this type of intermetallic material is described. Finally, the effect of two-step heat-treatments on the microstructure and the mechanical properties is discussed. Because of the small “deformation window” hot-working of -TiAl alloys is a complex and difficult task and, therefore, isothermal forming processes are favoured. In order to increase the deformation window a novel Nb and Mo containing -TiAl based alloy (TNMTM alloy) was developed, which solidifies via the β-phase and exhibits an adjustable β/B2-phase volume fraction. Due to high volume fractions of -phase at elevated temperatures the alloy can be hot-die forged under near conventional conditions, which means that conventional forging equipment with minor and inexpensive modifications can be used. Examples for the fabrication of -TiAl components employing a near conventional forging route are given. With subsequent heat-treatments balanced mechanical properties can be achieved. The results of tensile and creep tests conducted on forged and subsequently heat-treated TNMTM material are presented.
Influence of an apparent r-curve on strength and fracture statistics of ceramic laminates
Authors: Lube Tanja , Pascual Javier , Danzer Robert 
Published: August 2009

AbstractLaminates with strong interfaces and having compressive residual stresses in the outer layer are designed to have high strength and high reliability. Bending strength tests on such laminate specimens were performed and compared with tests made on monolithic specimens made from the outer layer material. In both types of specimens fracture started from similar flaws, but the laminate specimens showed a higher strength and Weibull modulus. In the case of the monolithic material the toughness is constant but in the case of the laminates it increases – due to the action of the residual stresses – with crack extension (i. e. it is an apparent toughness).The influence of the apparent toughness curve on the fracture statistics is discussed. It is also shown that the statistics of the laminate can be determined using the statistics of the monolithic material, if the influence of the residual stresses on the toughness and strength is properly taken into account.
Avoiding grain defects in single crystal components by application of a heat conductor technique
Authors: Ma Dexin , Bührig-Polaczek Andreas 
Published: August 2009

Abstract
During single crystal solidification in turbine blades, grain defects are often formed in the platform region with abrupt variation in cross-section. In order to reduce grain defects arising from component geometries an HC (Heat Conductor) technique was developed. In the production process for ceramic shell moulds, a graphite heat conductor of excellent heat conductivity is inserted close to the inner corner of the platform. This effectively extracts local heat from this critical region during directional solidification. Numerical simulations show that by using HC the thermal condition in the platform region can be significantly improved. The single crystal growth in the blade body can spread into the platform more quickly before the melt at the platform extremity becomes deeply undercooled. Structural investigations reveal a remarkable reduction in grain defect formation, providing confirmation of the effectiveness of the HC technique in improving the casting quality of single crystal components.
Discordance Between Self-report of Physician Diagnosis and Administrative Database Diagnosis of Arthritis and Its Predictors
Authors: SINGH JASVINDER A. 
Published: August 2009

Objective.To study predictors of discordance between self-reported physician diagnosis and administrative database diagnosis of arthritis.Methods.A cohort of all veterans who utilized Veterans Integrated Service Network (VISN)-13 medical facilities were mailed a questionnaire that included patient self-report of physician diagnosis of arthritis and questions regarding demographics, functional limitation, and SF-36V (a validated version of the Medical Outcomes Study Short-Form 36). Kappa coefficient was used to assess the extent of agreement between self-report of physician diagnosis and administrative database definitions that incorporated International Classification of Diseases (ICD) codes and use of medications for arthritis. We identified predictors of overall discordance between self-report and administrative database diagnosis using multivariable logistic regression analyses.Results.Among 70,334 eligible veterans surveyed, 19,749 subjects had an ICD diagnosis of arthritis in the administrative database in the year prior to the survey; 34,440 answered the arthritis question and 18,464 self-reported a physician diagnosis of arthritis. Kappa coefficient showed slight to fair agreement of 0.19–0.32 between self-report and administrative database definitions of arthritis. We found significantly higher overall discordance among veterans with more comorbidities, greater age, worse functional status, lower use of outpatient and inpatient services, lower education level, and among single medical-site users.Conclusion.Low level of agreement between self-report and database diagnosis of arthritis and its significant association with patient demographic, clinical, and functional characteristics highlights the limitation of use of these strategies for identification of patients with arthritis in epidemiological studies.