Presence of an alpha-amylase isozyme with high temperature optima in the wheat variety tolerant to high temperature at juvenile plant stage

2006 ◽  
Vol 28 (3) ◽  
pp. 205-215 ◽  
Author(s):  
Gurpreet Kaur Hunjan
Keyword(s):  
High Temperature ◽  
Wheat Variety ◽  
Alpha Amylase ◽  
Plant Stage ◽  
Temperature Optima ◽  
Juvenile Plant

scholarly journals Effect Of High Temperature On Yield Attributing Traits In Bread Wheat

1970 ◽  
Vol 36 (3) ◽  
pp. 415-426 ◽  
Author(s):  
Khajan Singh ◽  
SN Sharma ◽  
Yogendra Sharma
Keyword(s):  
High Temperature ◽  
Grain Yield ◽  
Bread Wheat ◽  
Temperature Stress ◽  
Wheat Variety ◽  
Triticum Aestivum L ◽  
High Temperature Stress ◽  
Major Constraint ◽  
Biological Yield ◽  
Heat Susceptibility Index

High temperature stress is major constraint to bread wheat (Triticum aestivum L. Em. Thell) production. Generation of information on the effect of high temperature stress on various traits may be helpful for developing thermotolerance bread wheat variety. An experiment was conducted on a set of 10 diverse genotypes, their 45 F1s and F2s for identification of high temperature stress genotype. The experiment was conducted under normal and late sown condition. The parent HD 2851, P8W 520, and HS 448, and the crosses HS 448 × PBW 520, UP 2614 × K 209 and PBW 520 × HD 2851 for grain yield per plant were least affected under late sown conditions. Heat stress intensity (Dvalue) clearly indicated that grain yield per pant biological yield per plant and grain yield per spike suffered revively under late sown conditions. Keywords: Bread wheat; heat susceptibility index; tolerant genotypes. DOI: http://dx.doi.org/10.3329/bjar.v36i3.9270 BJAR 2011; 36(3): 415-426

SEEDLING REACTIONS TO STEM RUST OF LINES OF MARQUIS WHEAT WITH SUBSTITUTED GENES FOR RUST RESISTANCE

1960 ◽  
Vol 40 (3) ◽  
pp. 524-538 ◽  
Author(s):  
G. J. Green ◽  
D. R. Knott ◽  
I. A. Watson ◽  
A. T. Pugsley
Keyword(s):  
High Temperature ◽  
North American ◽  
Stem Rust ◽  
Chinese Spring ◽  
Rust Resistance ◽  
Wheat Variety ◽  
Substitution Lines ◽  
Moderate Resistance

Lines of the wheat variety Marquis carrying genes Sr6, Sr7, Sr8, Sr9, Sr10, and Sr6 plus Sr7 for resistance to stem rust were produced by the backcross method. The reactions of these lines to 99 North American cultures of 29 races of stem rust and to 8 Australian cultures were determined. Genes Sr6, Sr8, and Sr9 conferred a uniform type of resistance to most of the cultures. Genes Sr7 and Sr10 conferred only moderate resistance to a few cultures. Genes Sr6, Sr8, and Sr9 appeared to confer the same kind of resistance in Marquis after 5 backcrosses as in the source varieties, but Sr7 and Sr10 seemed less effective. Results of the infection studies indicated that Sr7 may be allelic with a gene for resistance in Marquis and that at least two alleles conditioning different rust reactions may occur at the Sr9 locus. The reactions of the lines with Sr6, Sr8, and Sr9 were nearly identical with those of the Chinese Spring substitution lines, Red Egyptian XX, Red Egyptian VI, and Red Egyptian XIII respectively, which presumably have these genes. The data indicated that Sr6 is the same as SrKa1 and Sr9 is the same as SrKb1. The resistance of lines with Sr7, Sr8, and Sr9 was affected only slightly by temperature but the resistance of lines with Sr10 and especially of those with Sr6 diminished at high temperature.

scholarly journals High-Temperature Enzymatic Breakdown of Cellulose

2011 ◽  
Vol 77 (15) ◽  
pp. 5199-5206 ◽  
Author(s):  
Hongliang Wang ◽  
Fabio Squina ◽  
Fernando Segato ◽  
Andrew Mort ◽  
David Lee ◽  
...  
Keyword(s):  
Cell Wall ◽  
High Temperature ◽  
Cellulase Activity ◽  
Initial Activity ◽  
Glycosidic Bonds ◽  
Enzyme Substrate ◽  
Cellulose Breakdown ◽  
Temperature Operating ◽  
Temperature Optima ◽  
Wall Components

ABSTRACTCellulose is an abundant and renewable biopolymer that can be used for biofuel generation; however, structural entrapment with other cell wall components hinders enzyme-substrate interactions, a key bottleneck for ethanol production. Biomass is routinely subjected to treatments that facilitate cellulase-cellulose contacts. Cellulases and glucosidases act by hydrolyzing glycosidic bonds of linear glucose β-1,4-linked polymers, producing glucose. Here we describe eight high-temperature-operating cellulases (TCel enzymes) identified from a survey of thermobacterial and archaeal genomes. Three TCel enzymes preferentially hydrolyzed soluble cellulose, while two preferred insoluble cellulose such as cotton linters and filter paper. TCel enzymes had temperature optima ranging from 85°C to 102°C. TCel enzymes were stable, retaining 80% of initial activity after 120 h at 85°C. Two modes of cellulose breakdown, i.e., with endo- and exo-acting glucanases, were detected, and with two-enzyme combinations at 85°C, synergistic cellulase activity was observed for some enzyme combinations.

SOME CHARACTERISTICS OF PROTEINASES OF AN OBLIGATELY PSYCHROPHILIC RED-PIGMENTED BACTERIUM AND OF SERRATIA MARCESCENS

1963 ◽  
Vol 9 (6) ◽  
pp. 871-877 ◽  
Author(s):  
I. J. Mcdonald ◽  
Alice K. Chambers
Keyword(s):  
High Temperature ◽  
Serratia Marcescens ◽  
Proteolytic Enzymes ◽  
Enzyme System ◽  
Heat Inactivation ◽  
Psychrophilic Bacterium ◽  
Temperature Characteristics ◽  
Optimum Activity ◽  
Cold Tolerant ◽  
Temperature Optima

Supernatants of cultures of a red-pigmented psychrophilic bacterium and of a strain of Serratia marcescens contained proteolytic enzymes that hydrolyzed casein,/3-IactogIobuIin and haemoglobin. With casein as the substrate, optimum activity of the enzyme system of the psychrophile was at pH 10 and at 40-45 °C; optimum activity of the 5. marcescens enzyme system was at pH 9.0 and 45° C. Calcium stimulated activity and protected proteinases of both organisms against heat inactivation. Proteinases of both organisms possess high temperature characteristics and relatively high temperature optima. The results indicated that the proteinase system of the red psychrophile differs from those of some other cold-tolerant bacteria {Cytophaga and Pseudomonas) and that it is similar to but not identical with the proteinase system of Serratia marcescens.

scholarly journals It Is Hot in the Sun: Antarctic Mosses Have High Temperature Optima for Photosynthesis Despite Cold Climate

2020 ◽  
Vol 11 ◽  
Author(s):  
Alicia V. Perera-Castro ◽  
Melinda J. Waterman ◽  
Johanna D. Turnbull ◽  
Michael B. Ashcroft ◽  
Ella McKinley ◽  
...  
Keyword(s):  
High Temperature ◽  
Cold Climate ◽  
The Sun ◽  
Temperature Optima ◽  
Antarctic Mosses

scholarly journals High-temperature optima phosphatases from the cold-tolerant Arctic fungus Penicillium citrinum

2012 ◽  
Vol 31 (1) ◽  
pp. 11105 ◽  
Author(s):  
Puja Gawas-Sakhalkar ◽  
ShivMohan Singh ◽  
Simantini Naik ◽  
Rasik Ravindra
Keyword(s):  
High Temperature ◽  
Penicillium Citrinum ◽  
Cold Tolerant ◽  
Temperature Optima

scholarly journals A genetic study of cold resistance in wheat

1970 ◽  
Vol 15 (2) ◽  
pp. 197-208 ◽  
Author(s):  
C. N. Law ◽  
G. Jenkins
Keyword(s):  
Triticum Aestivum ◽  
Genetic Study ◽  
Chinese Spring ◽  
Cold Resistance ◽  
Cold Treatment ◽  
Substitution Lines ◽  
Plant Stage ◽  
Juvenile Plant

SUMMARYThe variety Chinese Spring of Triticum aestivum is susceptible to cold treatment applied at the juvenile plant stage, while the variety Cappelle-Desprez shows resistance to such treatment. By cytological and backcross procedures single homologous pairs of chromosomes from Cappelle-Desprez were substituted for their homologues in Chinese Spring. Assay experiments carried out on each of the 21 possible substitution lines indicated that three chromosomes, 4D, 5D and 7A of Cappelle-Desprez were involved in the determination of cold resistance. The resistance expressed by the three substitution lines carrying these chromosomes was less than the reaction of Cappelle-Desprez to cold treatment. Also the magnitude of this resistance supported a hypothesis that the action of the three chromosomes was additive on the scale of measurement used. The possible relationships of the genes for cold resistance to the established genes controlling other developmental characters, also carried by these three chromosomes, are discussed.

Influence of Thermo-Mechanical Processing on the Microstructure of Beryllia Dispersed Nickel Alloys

1973 ◽  
Vol 31 ◽  
pp. 184-185
Author(s):  
M.S. Grewal ◽  
S.A. Sastri ◽  
N.J. Grant
Keyword(s):  
High Temperature ◽  
Nickel Alloys ◽  
Thermomechanical Processing ◽  
Cold Work ◽  
High Temperature Strength ◽  
Strengthening Effect ◽  
Mechanical Processing ◽  
Uniform Dispersion ◽  
Oxide Particles ◽  
Nickel Base

Currently there is a great interest in developing nickel base alloys with fine and uniform dispersion of stable oxide particles, for high temperature applications. It is well known that the high temperature strength and stability of an oxide dispersed alloy can be greatly improved by appropriate thermomechanical processing, but the mechanism of this strengthening effect is not well understood. This investigation was undertaken to study the dislocation substructures formed in beryllia dispersed nickel alloys as a function of cold work both with and without intermediate anneals. Two alloys, one Ni-lv/oBeo and other Ni-4.5Mo-30Co-2v/oBeo were investigated. The influence of the substructures produced by Thermo-Mechanical Processing (TMP) on the high temperature creep properties of these alloys was also evaluated.

Application of TEM to Deformation, Wear, and Fracture of Ceramics

1974 ◽  
Vol 32 ◽  
pp. 472-473
Author(s):  
B. J. Hockey
Keyword(s):  
Wear Resistance ◽  
High Temperature ◽  
Mechanical Behavior ◽  
Brittle Materials ◽  
High Temperature Strength ◽  
Wide Range ◽  
Corrosive Environments ◽  
Further Development

Ceramics, such as Al2O3 and SiC have numerous current and potential uses in applications where high temperature strength, hardness, and wear resistance are required often in corrosive environments. These materials are, however, highly anisotropic and brittle, so that their mechanical behavior is often unpredictable. The further development of these materials will require a better understanding of the basic mechanisms controlling deformation, wear, and fracture.The purpose of this talk is to describe applications of TEM to the study of the deformation, wear, and fracture of Al2O3. Similar studies are currently being conducted on SiC and the techniques involved should be applicable to a wide range of hard, brittle materials.

Lattice Imaging of Grain Boundaries in Ceramics

1977 ◽  
Vol 35 ◽  
pp. 114-115
Author(s):  
D. R. Clarke ◽  
G. Thomas
Keyword(s):  
Mechanical Properties ◽  
High Temperature ◽  
Silicon Nitride ◽  
Grain Boundaries ◽  
High Temperature Strength ◽  
Current Interest ◽  
Lattice Imaging ◽  
Special Significance ◽  
Structural Applications ◽  
Refractory Ceramics

Grain boundaries have long held a special significance to ceramicists. In part, this has been because it has been impossible until now to actually observe the boundaries themselves. Just as important, however, is the fact that the grain boundaries and their environs have a determing influence on both the mechanisms by which powder compaction occurs during fabrication, and on the overall mechanical properties of the material. One area where the grain boundary plays a particularly important role is in the high temperature strength of hot-pressed ceramics. This is a subject of current interest as extensive efforts are being made to develop ceramics, such as silicon nitride alloys, for high temperature structural applications. In this presentation we describe how the techniques of lattice fringe imaging have made it possible to study the grain boundaries in a number of refractory ceramics, and illustrate some of the findings.

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