MAJOR AND MINOR GENES IN WHEAT FOR RESISTANCE TO PUCCINIA STRIIFORMIS AND THEIR RESPONSES TO TEMPERATURE CHANGES

1967 ◽  
Vol 45 (11) ◽  
pp. 2155-2172 ◽  
Author(s):  
R. T. Lewellen ◽  
E. L. Sharp ◽  
E. R. Hehn
Keyword(s):  
Temperature Profile ◽  
Puccinia Striiformis ◽  
Major Gene ◽  
Wheat Varieties ◽  
Major Genes ◽  
Temperature Changes ◽  
Minor Genes ◽  
Higher Temperature ◽  
Lower Temperature ◽  
Moderate Resistance

The wheat varieties, 'P.I. 178383' and 'Chinese 166' (Triticum aestivum), were each found to carry an incompletely dominant major gene for resistance to a single pathogenic type of Puccinia striiformis. In addition, an undetermined number of minor genes segregated in such a way that in certain combinations they conferred moderate resistance and modified the action of the major genes. The rust readings were made on seedling plants grown in strictly controlled-environment chambers that simulated natural conditions. The action of the major genes was not affected by different temperature profiles, but the minor genes gave better resistance at a higher temperature profile than at a lower temperature profile.

Inheritance of minor reaction gene combinations in wheat to Puccinia striiformis at two temperature profiles

1968 ◽  
Vol 46 (1) ◽  
pp. 21-26 ◽  
Author(s):  
R. T. Lewellen ◽  
E. L. Sharp
Keyword(s):  
Puccinia Striiformis ◽  
Infection Type ◽  
Major Gene ◽  
Temperature Sensitive ◽  
Temperature Profiles ◽  
Additive Interaction ◽  
Wheat Varieties ◽  
Lower Temperature ◽  
Two Temperature ◽  
Dominant Genes

The inheritance of resistance of Rego and P. I. 178383 wheat varieties to a specific pathogenic type of Puccinia striiformis, stripe rust, was investigated at two temperature profiles, 2 C night / 18 C day and 15 C night / 24 C day. Mean infection type on Rego was a 0 at 2/18 and a 3− at 15/24. Two complementary dominant genes conferred about a 3− reaction at both profiles. In addition, one or more recessive temperature-sensitive genes contributed to the greater level of resistance of Rego at the lower temperature profile. P. I.178383 has one major gene conditioning rust resistance and an undetermined number of minor genes that express greater resistance at 15/24 than at 2/18. In combination with the Rego factors, there is an additive interaction at both temperature profiles for greater resistance.

ERYSIPHE GRAMINIS IN CANADA

1947 ◽  
Vol 25c (2) ◽  
pp. 73-94 ◽  
Author(s):  
Margaret Newton ◽  
W. J. Cherewick
Keyword(s):  
British Columbia ◽  
Powdery Mildew ◽  
Erysiphe Graminis ◽  
Wheat Varieties ◽  
Physiologic Specialization ◽  
Higher Temperature ◽  
Lower Temperature

A study has been made of powdery mildew (Erysiphe graminis DC.) in Canada, including its distribution, the physiologic specialization of its two varieties, Hordei and Tritici, and the reactions of barley and wheat hosts to the prevalent races of the two varieties of mildew. The fungus occurs throughout Canada but it is most prevalent in British Columbia, Ontario, and Quebec. Nine races of E. graminis Hordei and three of E. graminis Tritici have been identified. Races 3, 6, 8, and 9 of the former, and races 4 and 5 of the latter are the most common in Canada. At a higher temperature (25 °C.) practically all the races of mildew developed a more resistant type of infection than at a lower temperature (15 °C.). The only exception was race 6 of E. graminis Hordei, which thrived fairly well at the higher temperature.The reactions of 246 varieties and strains of barley to nine races of barley mildew and the reactions of 124 wheat varieties and strains to two races of wheat mildew indicate that there are varieties of both cereals that are resistant to powdery mildew.

scholarly journals Genetic Behavior of Controlling Area Under Disease Progress Curve for Stripe Rust (Puccinia striiformis f. sp. tritici) in Two Wheat (Triticum aestivum) Crosses

2009 ◽  
Vol 99 (11) ◽  
pp. 1265-1272 ◽  
Author(s):  
Muhammad Irfaq ◽  
Mir Ajab ◽  
Gul Sanat Shah Khattak ◽  
Tila Mohammad ◽  
Syed Jawad Ahmad Shah
Keyword(s):  
Stripe Rust ◽  
Puccinia Striiformis ◽  
Major Gene ◽  
Epistatic Effect ◽  
Genetic Effects ◽  
Stripe Rust Resistance ◽  
Major Genes ◽  
Disease Progress Curve ◽  
Disease Progress ◽  
Progress Curve

Genetic effects on controlling resistance to stripe rust (Puccinia striiformis f. sp. tritici Eriksson)were determined in two wheat crosses, Bakhtawar-92 (B-92) × Frontana and Inqilab-91 × Fakhre Sarhad using area under the disease progress curve (AUDPC) as a measure of stripe rust resistance. The resistant and susceptible parents involved in developing genetic populations were identified by initial assessment of 45 wheat accessions for stripe rust reaction. Mixed inheritance model was applied to the data analysis of six basic populations (P1, F1, P2, B1, B2, and F2) in the crosses. The results indicated that AUDPC in cross 1 was controlled by two major genes with additive-dominance epistatic effect plus polygenes with additive-dominance-epistatic effects (model E) whereas, in the case of cross 2, it was under the control of two major genes with additive-dominance epistatic effect plus additive-dominant polygenes (model E-1). Additive effect was predominant over all other types of genetic effects, suggesting that the delay in selection for resistance until maximum favorable genes are accumulated in the individuals is desired. The tendency of backcrosses toward their respective pollen donor parents indicated the control of resistance through nuclear genes rather than the cytoplasmic factors. Occurrence of resistant as well as susceptible transgressive segregates (though very few in F2 for each cross) indicated the presence of favorable as well as some adverse genes for resistance to stripe rust in the parents. The major gene heritability was higher than that of the polygene in B1, B2, and F2 for the crosses. The major gene as well as the polygene heritability was 48.99 to 87.12% and 2.26 to 36.80% for the two crosses, respectively. The highest phenotypic variations in AUDPC (2,504.10 to 5,833.14) for segregating progenies (B1, B2, and F2) represent that the character was highly influenced by the environment. The experimental results of the two crosses indicate that resistance to stripe rust is under control of two major genes in association with several polygene rather than cytoplasmic inheritance.

The inheritance of genetic variation in Triticum speltoides affecting heterogenetic chromosome pairing in hybrids with Triticum aestivum

1984 ◽  
Vol 26 (3) ◽  
pp. 279-287 ◽  
Author(s):  
K. C. Chen ◽  
J. Dvořák
Keyword(s):  
Triticum Aestivum ◽  
Genetic Variation ◽  
Chromosome Pairing ◽  
Major Gene ◽  
Diploid Species ◽  
Duplicate Gene ◽  
The Other ◽  
Major Genes ◽  
Minor Genes

Triticum speltoides (Tausch) Gren. ex Richter plants which differed in the ability to promote heterogenetic chromosome pairing in hybrids T. aestivum L. × T. speltoides were crossed and a single F1 plant from each cross was hybridized with T. aestivum. The segregation among the hybrids for mean number of chiasmata per cell showed that two gene systems in T. speltoides genotypes were involved in the promotion of heterogenetic pairing. One system was composed of two duplicate gene loci segregating independently of each other. Variation at these loci determined two basic levels of heterogenetic pairing. The other system was composed of several minor genes extensively modifying the effects of the major genes. The minor genes interacted mostly in an additive fashion. Triticum speltoides inbred plants were then crossed with diploid species. T. tauschii (Coss.) Schmal and T. dichasians (Zhuk.) Bowden. Consistent differences in the levels of chromosome pairing were found in these hybrids. However, this variation in chromosome pairing did not coincide with the variation at the major gene loci. This indicated that the major genes were ineffective in the diploid hybrids.Key words: Triticum, pairing regulation, homeologous pairing, heterogenetic pairing.

scholarly journals Sprouting of Sorghum (Sorghum bicolor [L.] Moench): Effect of Drying Treatment on Protein and Starch Features

Foods ◽  
2021 ◽  
Vol 10 (2) ◽  
pp. 407 ◽  
Author(s):  
Mia Marchini ◽  
Alessandra Marti ◽  
Claudia Folli ◽  
Barbara Prandi ◽  
Tommaso Ganino ◽  
...  
Keyword(s):  
Food Production ◽  
Cost Effective ◽  
High Exposure ◽  
Effective Technology ◽  
Drying Treatment ◽  
Higher Temperature ◽  
Lower Temperature ◽  
The One ◽  
Drying Conditions ◽  
Sorghum Bicolor L

The nutritional and physicochemical properties of sorghum proteins and starch make the use of this cereal for food production challenging. Sprouting is a cost-effective technology to improve the nutritional and functional profile of grains. Two drying treatments were used after sorghum sprouting to investigate whether the drying phase could improve the protein and starch functionalities. Results showed that the drying treatment at lower temperature/longer time (40 °C for 12 h) extended the enzymatic activity that started during sprouting compared to the one performed at higher temperature/shorter time (50 °C for 6 h). An increased protein hydrolysis and water- and oil-holding capacity were found in the flour obtained by the former treatment. Higher protein matrix hydrolysis caused high exposure of starch to enzymes, thus increasing its digestibility, while worsening the technological functionality. Overall, modulating drying conditions could represent a further way, in addition to sprouting, to improve sorghum flour’s nutritional profile.

MICROSTRUCTURAL EVOLUTION OF Al-Cu-Mg-Ag ALLOY WITH TRACE Zr ADDITION DURING TWO-STEP HOMOGENIZATION

2009 ◽  
Vol 23 (06n07) ◽  
pp. 855-862 ◽  
Author(s):  
FEIYUE MA ◽  
ZHIYI LIU
Keyword(s):  
Melting Point ◽  
Grain Boundaries ◽  
Microstructural Evolution ◽  
Cast Alloy ◽  
Scanning Calorimetry ◽  
Zr Addition ◽  
Homogenization Time ◽  
The Matrix ◽  
Higher Temperature ◽  
Lower Temperature

The microstructural evolution in an Al - Cu - Mg - Ag alloy with trace Zr addition during homogenization treatment was characterized by Differential Scanning Calorimetry (DSC), Scanning Electron Microscopy (SEM) and Energy-dispersive X-ray Spectroscopy (EDS). It was shown that the low-melting-point phase segregating toward grain boundaries is Al 2 Cu , with a melting point of 523.52°C. A two-step homogenization process was employed to optimize the microstructure of the as-cast alloy, during which the alloy was first homogenized at a lower temperature, then at a higher temperature. After homogenized at 420°C for 6 h, Al 3 Zr particles were finely formed in the matrix. After that, when the alloy was homogenized at an elevated temperature for a longer time, i.e., 515°C for 24 h, most of the precipates at the grain boundaries were removed. Furthermore, the dispersive Al 3 Zr precipitates were retained, without coarsening greatly in the final homogenization step. A kinetics model is employed to predict the optimal homogenization time at a given temperature theoretically, and it confirms the result in present study, which is 420°C/6h+515°C/24h.

scholarly journals Research on the Static Recrystallization and Precipitation Behaviors of a V-N Microalloyed Steel

2013 ◽  
Vol 2013 ◽  
pp. 1-7 ◽  
Author(s):  
Baochun Zhao ◽  
Tan Zhao ◽  
Guiyan Li ◽  
Qiang Lu
Keyword(s):  
Static Recrystallization ◽  
Microalloyed Steel ◽  
Time Interval ◽  
Main Role ◽  
Recrystallization Process ◽  
Compression Tests ◽  
Double Compression ◽  
Higher Temperature ◽  
Lower Temperature ◽  
Temperature Strain

Double compression tests were performed on a Gleeble-3800 thermomechanical simulator to study the softening behaviors of deformed austenite in a V-N microalloyed steel. The static recrystallization volume fractions were calculated by stress offset method, and the kinetic model of static recrystallization was constructed. The effects of temperature, strain, and time interval on the softening behaviors were analyzed, and the interactions between precipitation and recrystallization were discussed. The results show that the softening behaviors of the deformed austenite at lower temperature or higher temperature are markedly different. At the temperature of 850°C or 800°C, pinning effects of the precipitates play the main role, and the recrystallization process is inhibited, which leads to the formation of plateaus in the softening curves. An increase in strain promotes the precipitation and recrystallization processes while reduces the inhibition effect of precipitation on recrystallization as well.

Effects of Sr Addition on Mechanical Properties and Microstructure of Mg-6Al Magnesium Alloy

2011 ◽  
Vol 686 ◽  
pp. 120-124
Author(s):  
Jin Ping Fan ◽  
She Bin Wang ◽  
Bing She Xu
Keyword(s):  
Mechanical Properties ◽  
Tensile Strength ◽  
Magnesium Alloy ◽  
Strengthening Mechanism ◽  
Microstructure And Mechanical Properties ◽  
Higher Temperature ◽  
Lower Temperature

The effects of Sr addition on the mechanical properties and microstructure of Mg-6Al mag- nesium alloy both at 25 °C and at 175 °C were investigated by means of OM, SEM and EDS and XRD. Upon the Sr addition of 2%, the tensile strength was increased by 7.2% to 184.4MPa at 25 °C, while it was increased by 30% to 155.4MPa at 175 °C. The strengthening mechanism of Mg-6Al-xSr at lower temperature (25 °C) was different from that at higher temperature (175°C). The results show that the addition of strontium effectively improved the microstructure and mechanical properties of magnesium alloy.

The Effect of Uniaxial Cyclic Deformation on the Evolution of Phase Transformation Fronts in Pseudoelastic NiTi Wire

2001 ◽  
Author(s):  
Mark A. Iadicola ◽  
John A. Shaw
Keyword(s):  
Mechanical Response ◽  
Infrared Imaging ◽  
Partial Transformation ◽  
Niti Wire ◽  
Full Field ◽  
Temperature Experiment ◽  
Background Temperature ◽  
Higher Temperature ◽  
Lower Temperature ◽  
Niti Wires

Abstract Experiments are presented of the response of pseudoelastic NiTi wires subjected to displacement controlled cycles. A custom built thermo-mechanical testing apparatus is used to control the background temperature field of the wire specimen while allowing the evolution of transformation fronts to be tracked by full field infrared imaging. Two experiments under similar end-displacement histories, but at temperatures ≈8°C apart, are shown to give remarkably different cyclic responses. The mechanical response for the lower temperature experiment continued to soften but retained its shape through 43 partial transformation cycles, and the pattern of transformation fronts seemed to reach a steady state. The response for the higher temperature experiment showed a change in shape of the mechanical response and distinct changes in transformation front patterns over 31 partial transformation cycles.

A Numerical Analysis of Gas Turbine Disks Incorporating Rotating Heat Pipes

2000 ◽  
Author(s):  
Y. Cao ◽  
J. Ling ◽  
R. Rivir ◽  
C. MacArthur
Keyword(s):  
Heat Pipe ◽  
Gas Turbine ◽  
Heat Pipes ◽  
High Heat ◽  
Thermal Dissipation ◽  
High Heat Flux ◽  
Heating And Cooling ◽  
Turbine Disks ◽  
Higher Temperature ◽  
Lower Temperature

Abstract Radially rotating heat pipes have been proposed for cooling gas turbine disks working at high temperatures. A disk incorporating the heat pipe would have an enhanced thermal dissipation capacity and a much lower temperature at the disk rim and dovetail surface. In this paper, extensive numerical simulations have been made for heat-pipe-cooled disks. Thermal performances are compared for the disks with and without incorporating the heat pipe at different heating and cooling conditions. The numerical results presented in this paper indicate that radially rotating heat pipes can significantly reduce the maximum and average temperatures at the disk rim and dovetail surface under a high heat flux working condition. In general, the maximum and average temperatures at the disk rim and dovetail surface could be reduced by above 250 and 150 degrees, respectively, compared to those of the disk without the heat pipe. As a result, a disk incorporating radially rotating heat pipes could alleviate temperature-related problems and allow a gas turbine to work at a much higher temperature.

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