Relationship of glaucousness and epicuticular wax quantity of wheat

1993 ◽  
Vol 73 (4) ◽  
pp. 961-967 ◽  
Author(s):  
J. M. Clarke ◽  
T. N. McCaig ◽  
R. M. DePauw
Keyword(s):  
Triticum Turgidum ◽  
Flag Leaf ◽  
Triticum Aestivum L ◽  
Epicuticular Wax ◽  
Visual Selection ◽  
Resistance To Insects ◽  
Triticum Spp ◽  
Selection For ◽  
Relationship Of

The quantity of epicuticular waxes of crops such as wheat (Triticum spp.) influences water relations, wettability by pesticide sprays, and resistance to insects and diseases. Determination of wax quantity for selection purposes is difficult, whereas visual selection for degree of glaucousness would be simple. However, the relationship between wax quantity and glaucousness is unclear. Common (T. aestivum L.) and durum (T. turgidum L. var. durum) inbred genotypes, nonglaucous/glaucous isogenics, and segregating families were grown under field conditions near Swift Current, Saskatchewan. Waxes were extracted with petroleum ether and determined gravimetrically for flag leaf sheaths, blades or spikes sampled 1–2 wk post-anthesis, and compared with visual glaucousness ratings. Wax quantity was generally lower for nonglaucous than for glaucous genotypes, but there was some overlap of observed quantities for the two groups. On average, wax was 44% greater for glaucous than for nonglaucous durum genotypes, and 32% greater for glaucous than for nonglaucous common wheat genotypes. Visual selection for glaucousness is thus likely to produce differences in epicuticular wax quantity, but the quantity difference would have to be verified at advanced generations. Key words: Triticum aestivum L., Triticum turgidum L. var. durum, glaucousness, epicuticular wax

THE EFFECTS OF GLAUCOUSNESS, EPICUTICULAR WAX, LEAF AGE, PLANT HEIGHT, AND GROWTH ENVIRONMENT ON WATER LOSS RATES OF EXCISED WHEAT LEAVES

1988 ◽  
Vol 68 (4) ◽  
pp. 975-982 ◽  
Author(s):  
J. M. CLARKE ◽  
R. A. RICHARDS
Keyword(s):  
Plant Height ◽  
Transpiration Rate ◽  
Water Loss ◽  
Triticum Turgidum ◽  
Leaf Age ◽  
Soil Surface ◽  
Triticum Aestivum L ◽  
Epicuticular Wax ◽  
Growth Environment ◽  
Residual Transpiration

Water loss at minimum stomatal aperture (residual transpiration) from plant surfaces accounts for a substantial proportion of total transpiration during periods of water stress and at night. Its reduction by genetic selection has been suggested as a desirable objective in water-limited environments. To identify genetic and environmental sources of variation in residual transpiration of wheat (Triticum spp.), the effects of glaucousness, epicuticular wax, leaf age, plant height, and growth environment were determined using excised leaves. Glaucousness reduced residual transpiration by an average of 10%. Differing quantities of epicuticular wax and glaucousness in an isogenic pair of genotypes affected residual transpiration as well, the rate being 33% greater in the low wax, nonglaucous than in the high wax, glaucous line. Residual transpiration rate of flag leaves of field-grown plants increased with leaf age, particularly during the 7 d following ligule appearance. The rate of residual transpiration was greater in tall than in dwarf near-isogenic lines. Residual transpiration of leaves from plants grown in glasshouses was 44–66% lower than that of plants grown outdoors, which had a mean rate of 2.68 × 10−5 g H2O cm−2 min−1. Method of water application to glasshouse plants influenced residual transpiration rate. The rate for leaves of plants watered by spraying water onto the plant and soil surface was 20% greater than that of leaves of plants watered on the soil surface only. It was concluded that the increase in residual transpiration rate with leaf age was due to duration of exposure to the rigors of the exterior environment; the absence of this in controlled environments results in lower rates of residual transpiration than in the field.Key words: Cuticular transpiration, Triticum aestivum L., Triticum turgidum L. var. durum, wheat

DYNAMICS OF DRY MATTER, N AND P ACCUMULATION IN THE DEVELOPING KERNELS OF FOUR SPRING WHEAT CULTIVARS FOR IRRIGATION AND DRYLAND

1990 ◽  
Vol 70 (4) ◽  
pp. 1043-1056 ◽  
Author(s):  
C. A. CAMPBELL ◽  
H. W. CUTFORTH ◽  
F. SELLES ◽  
R. M. DEPAUW ◽  
J. M. CLARKE
Keyword(s):  
Dry Matter ◽  
Triticum Turgidum ◽  
Triticum Aestivum L ◽  
Dry Matter Accumulation ◽  
N Accumulation ◽  
Logistic Equations ◽  
P Concentration ◽  
P Accumulation ◽  
Triticum Spp ◽  
Lower Protein

The effect of moisture and cultivar on the dynamics of N and P concentration and on dry matter, N and P accumulation of the developing central kernels on the main spike of four wheat (Triticum spp.) cultivars were determined. Two common wheat (T. aestivum L.) cultivars, Neepawa and HY320, and two durum (T. turgidum L. var. durum) cultivars, DT367 and Wakooma, were grown on an Orthic Brown Chernozem in southwestern Saskatchewan in 1985. HY320 and DT367 have higher grain yield potentials and lower protein concentrations than Neepawa and Wakooma. Logistic equations satisfactorily decribed the accumulation patterns of dry matter, N, and P contents in the kernels from anthesis to maturity, while linear and second degree polynomials adequately described the variations in N and P concentrations. Response of N and P concentration to moisture and cultivar was variable but could be explained in terms of rate and amount of dry matter accumulation in kernels and the greater mobility and availability of N compared to P in soil. N and P accumulation was mainly dependent on kernel dry matter response, although N and P concentration did influence accumulation patterns under irrigation. Duration of accumulation of dry matter, N and P in kernels were equal under dryland, but under irrigation the period was several days longer for N than for dry matter and P. Cultivar had no effect on duration of N accumulation under irrigation, but on dryland duration was shortest for Neepawa. For P accumulation, duration was longest for HY320. The mean rates of accumulation of kernel dry matter, N, and P were directly related (R2 = 0.98**) to kernel dry matter, N, and P content, respectively.Key words: Wheat, Triticum aestivum L., Triticum turgidum L. var. durum, filling rate, filling duration

scholarly journals DETERMINATION OF CHARACTERS FOR YIELD SELECTION IN SPRING WHEAT

1973 ◽  
Vol 53 (4) ◽  
pp. 755-762 ◽  
Author(s):  
H. G. NASS
Keyword(s):  
Spring Wheat ◽  
Harvest Index ◽  
Flag Leaf ◽  
Effective Means ◽  
Triticum Aestivum L ◽  
Morphological Characters ◽  
Kernel Weight ◽  
Plot Yield ◽  
Flag Leaf Width

A 2-yr study of 22 cultivars of spring wheat (Triticum aestivum L.) showed that yield per ear and number of ears per plant reduced yield variance the most in stepwise regression analysis. These two components of yield were negatively correlated. Harvest index, kernels per ear, and yield per ear were associated with plot yield. Kernels per ear and kernel weight were associated with yield per ear. Morphological characters influenced plot yield indirectly in that ear area, flag leaf width, and total photosynthetic area above the flag leaf node were associated with yield per ear. Ears per plant, yield per ear, and harvest index considered together in a selection program should be an effective means of selecting for increased yield.

scholarly journals Determination of allelic variants of gene Glu-1 in hybrid families, bearing gene Gpc-B1 of Triticum turgidum ssp. dicoccoides

1970 ◽  
Vol 21 ◽  
pp. 168-173
Author(s):  
S. Yu. Pokhylko ◽  
A. I. Stepanenko ◽  
O. M. Dugan ◽  
B. V. Morgun
Keyword(s):  
Triticum Turgidum ◽  
Molecular Genetic ◽  
Triticum Aestivum L ◽  
Molecular Genetic Analysis ◽  
Kernel Weight ◽  
Allelic Variants ◽  
Allelic State ◽  
Soft Winter Wheat ◽  
And Performance

Aim. The aim of our study was to analyze the hybrid families of generation F5 carrying gene Gpc-B1 of Triticum turgidum ssp. dicoccoides for the allelic state of Glu-1, to calculate 1000 kernel weight and to select families with the best set of alleles and performance. Methods. Polymerase chain reaction for molecular genetic analysis and calculation of the 1,000-kernel weight for wheat grain yields were used. Results. Determination of the three loci Glu-A1, Glu-B1, Glu-D1 shows that among 44 hybrid families it is possible to identify 16 most promising families that have the most valuable allelic variants. Furthemore, given the analysis of the 1,000-kernel weight, two families (#36 and 40) having the highest values can be selected among those 16 families. Conclusions. The results of study enable a comprehensive approach to the selection of progeny with the best genetic base, which will be used in breeding of soft winter wheat later on. Keywords: Triticum aestivum L., gene Gpc-B1, Glu-1 loci, PCR, molecular markers.

STEM and ELS Observation of Early Oxide Formation on the Surface of Cr Thin Films

1980 ◽  
Vol 38 ◽  
pp. 412-413
Author(s):  
Fumio Watari ◽  
J. M. Cowley
Keyword(s):  
Thin Films ◽  
Optical System ◽  
Room Temperature ◽  
Oxide Formation ◽  
Initial Nucleation ◽  
Diffraction Patterns ◽  
Relationship Of ◽  
Multiple Twinning ◽  
Moderately High Temperature

STEM coupled with the optical system was used for the investigation of the early oxidation on the surface of Cr. Cr thin films (30 – 1000Å) were prepared by evaporation onto the polished or air-cleaved NaCl substrates at room temperature and 45°C in a vacuum of 10−6 Torr with an evaporation speed 0.3Å/sec. Rather thick specimens (200 – 1000Å) with various preferred orientations were used for the investigation of the oxidation at moderately high temperature (600 − 1100°C). Selected area diffraction patterns in these specimens are usually very much complicated by the existence of the different kinds of oxides and their multiple twinning. The determination of the epitaxial orientation relationship of the oxides formed on the Cr surface was made possible by intensive use of the optical system and microdiffraction techniques. Prior to the formation of the known rhombohedral Cr2O3, a thin spinel oxide, probably analogous to γ -Al203 or γ -Fe203, was formed. Fig. 1a shows the distinct epitaxial growth of the spinel (001) as well as the rhombohedral (125) on the well-oriented Cr(001) surface. In the case of the Cr specimen with the (001) preferred orientation (Fig. 1b), the rings explainable by spinel structure appeared as well as the well defined epitaxial spots of the spinel (001). The microdif fraction from 20A areas (Fig. 2a) clearly shows the same pattern as Fig. Ia with the weaker oxide spots among the more intense Cr spots, indicating that the thickness of the oxide is much less than that of Cr. The rhombohedral Cr2O3 was nucleated preferably at the Cr(011) sites provided by the polycrystalline nature of the present specimens with the relation Cr2O3 (001)//Cr(011), and by further oxidation it grew into full coverage of the rest of the Cr surface with the orientation determined by the initial nucleation.

Calculating the aerodynamics of vertical axis wind turbines

2012 ◽  
Vol 34 (3) ◽  
pp. 169-184 ◽  
Author(s):  
Hoang Thi Bich Ngoc
Keyword(s):  
Wind Turbine ◽  
Incidence Angle ◽  
Vertical Axis ◽  
Rotor Blades ◽  
Vertical Axis Wind Turbine ◽  
Horizontal Axis Wind Turbine ◽  
Velocity Triangle ◽  
Relationship Of ◽  
The Relationship

Vertical axis wind turbine technology has been applied last years, very long after horizontal axis wind turbine technology. Aerodynamic problems of vertical axis wind machines are discussible. An important problem is the determination of the incidence law in the interaction between wind and rotor blades. The focus of the work is to establish equations of the incidence depending on the blade azimuth, and to solve them. From these results, aerodynamic torques and power can be calculated. The incidence angle is a parameter of velocity triangle, and both the factors depend not only on the blade azimuth but also on the ratio of rotational speed and horizontal speed. The built computational program allows theoretically selecting the relationship of geometric parameters of wind turbine in accordance with requirements on power, wind speed and installation conditions.

Tire Treadwear — A Comprehensive Evaluation of the Factors: Generic Type, Aspect Ratio, Tread Pattern, and Tread Composition Part I: Introduction and Details on the Organization of the Program

1986 ◽  
Vol 14 (4) ◽  
pp. 201-218 ◽  
Author(s):  
A. G. Veith
Keyword(s):  
Aspect Ratio ◽  
Comprehensive Evaluation ◽  
Test Method ◽  
Interactive Effects ◽  
Data Analyses ◽  
Main Effect ◽  
Systematic Determination ◽  
Relationship Of ◽  
The Relationship

Abstract This four-part series of papers addresses the problem of systematic determination of the influence of several tire factors on tire treadwear. Both the main effect of each factor and some of their interactive effects are included. The program was also structured to evaluate the influence of some external-to-tire conditions on the relationship of tire factors to treadwear. Part I describes the experimental design used to evaluate the effects on treadwear of generic tire type, aspect ratio, tread pattern (groove or void level), type of pattern (straight rib or block), and tread compound. Construction procedures and precautions used to obtain a valid and functional test method are included. Two guiding principles to be used in the data analyses of Parts II and III are discussed. These are the fractional groove and void concept, to characterize tread pattern geometry, and a demonstration of the equivalence of wear rate for identical compounds on whole tread or multi-section tread tires.

Quantification of the kinetic differences between communities isolated from completely mixed activated sludge systems operated with or without a selector using a novel respirometric method

1994 ◽  
Vol 30 (11) ◽  
pp. 255-261 ◽  
Author(s):  
Barth F. Smets ◽  
Timothy G. Ellis ◽  
Stephanie Brau ◽  
Richard W. Sanders ◽  
C. P. Leslie Grady
Keyword(s):  
Oxygen Consumption ◽  
Activated Sludge ◽  
Physiological Changes ◽  
Biodegradation Kinetics ◽  
Substrate Removal ◽  
Biomass Yields ◽  
Selection For ◽  
Single Oxygen ◽  
Activated Sludge Systems

This study quantified the kinetic differences in microbial communities isolated from completely mixed activated sludge (CMAS) systems that were operated either with or without an aerobic selector preceding the main reactor. A new respirometric method was employed that allowed the determination of biodegradation kinetics from single oxygen consumption curves, thereby minimizing physiological changes to the examined communities during the assay. Results indicated that increased values for Ks and μmax for acetate, phenol, and 4-chlorophenol degradation were measured in the CMAS system operated with a selector. The biomass yields on acetate, phenol, and 4-chlorophenol were very similar in both systems. These findings indicate that the operation of CMAS systems with aerobic selectors may result in the selection for degrading populations with higher Ks and μmax values for both biogenic and xenobiotic organic compounds, and that substrate storage in the selector only partially contributes to increased substrate removal rates.

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