Physiological Basis of Genetic Differences in the Growth of Grains of Six Varieties of Wheat

1978 ◽  
Vol 5 (3) ◽  
pp. 249 ◽  
Author(s):  
CF Jenner ◽  
AJ Rathjen
Keyword(s):  
Genetic Variation ◽  
Dry Matter ◽  
Kinetic Properties ◽  
Wheat Grain ◽  
Physiological Basis ◽  
Rate Of Growth ◽  
Insoluble Material ◽  
Two Parameters ◽  
The Relationship ◽  
Rate Of Accumulation

The physiological basis of genetic variation in rate of accumulation of dry matter (growth) in wheat grain has been investigated by culturing ears of six different varieties on solutions of sucrose. Differences between varieties in accumulation of dry matter in the cultured ears were similar to those for grains growing in the field. Intracellular concentration of sucrose was positively correlated with increases in dry matter in treatments within varieties, but was not related to differences between varieties. In comparisons between varieties, high intracellular levels of sucrose were more often associated with low rates of accumulation of dry matter than with high rates. It is concluded that, within the varieties investigated here, genetic variation in the rate of deposition of dry matter in the endosperm is not attributable to variation in supply of assimilate to the grain. No single or simple parameter of the growth of the grain at anthesis, or in the succeeding 2 weeks, was related to the grain's subsequent rate of growth. The weight of ethanol-insoluble material in the endosperm itself at day 19 was not indicative of the amounts of this fraction deposited in the endosperm in the week that followed day 19. Significant variation between the varieties was observed in the relationship (viz. the slope) between the intracellular amounts of sucrose and the rate of accumulation of ethanol-insoluble dry matter (mostly starch), a relationship which is presumed to reflect kinetic properties of the process(es) converting sucrose to starch. In the six varieties investigated, all the observed differences in grain growth rate could be attributed to variation in the slope defined above, and/or in day 19 endosperm dry matter. It is suggested that these two parameters reflect two independent physiological determinants, accounting for much of the genetic variation in the rate of growth of wheat grain.

Exergy analysis of a turboprop engine at different flight altitude and speeds using novel consideration

2020 ◽  
Vol 0 (0) ◽  
Author(s):  
Ali Dinc ◽  
Yousef Gharbia
Keyword(s):  
Fuel Consumption ◽  
Thermal Efficiency ◽  
Exergy Efficiency ◽  
Specific Fuel Consumption ◽  
Flight Altitude ◽  
Fuel Flow ◽  
Turboprop Engine ◽  
Shaft Power ◽  
Two Parameters ◽  
The Relationship

Abstract In this study, exergy efficiency calculations of a turboprop engine were performed together with main performance parameters such as shaft power, specific fuel consumption, fuel flow, thermal efficiency etc., for a range of flight altitude (0–14 km) and flight speeds (0–0.6 Mach). A novel exergy efficiency formula was derived in terms of specific fuel consumption and it is shown that these two parameters are inversely proportional to each other. Moreover, a novel exergy efficiency and thermal efficiency relation was also derived. The relationship showed that these two parameters are linearly proportional to each other. Exergy efficiency of the turboprop engine was found to be in the range of 23–33%. Thermal efficiency of the turboprop engine was found to be around 25–35%. Exergy efficiency is higher at higher speeds and altitude where the specific fuel consumption is lower. Conversely, exergy efficiency of the engine is lower for lower speeds and altitude where the specific fuel consumption is higher.

scholarly journals Study of the Soil—Plant (Carrot)—Animal Cycle of Nutritive and Hazardous Minerals in a Rabbit Model

1999 ◽  
Vol 47 (2) ◽  
pp. 181-190 ◽  
Author(s):  
A. Bersényi ◽  
S. Fekete ◽  
I. Hullár ◽  
I. Kádár ◽  
M. Szilágyi ◽  
...  
Keyword(s):  
Crude Protein ◽  
Dry Matter ◽  
Rabbit Model ◽  
Basal Diet ◽  
The Body ◽  
High Concentration ◽  
New Zealand White Rabbits ◽  
Heavy Metal Salts ◽  
Experimental Treatments ◽  
Rate Of Accumulation

Carrots were grown on soils polluted by heavy metal salts. Each particular microelement reached a high concentration [molybdenum (Mo) 39.00, cadmium (Cd) 2.30, lead (Pb) 4.01, mercury (Hg) 30.00, and selenium (Se) 36.20 mg/kg dry matter] in the carrot. In a metabolic balance trial conducted with 15 male and 15 female New Zealand White rabbits, the control animals (n = 5) were fed ad libitum with concentrate as basal diet, while the other rabbits received the basal diet and carrots containing the particular microelement. Blood samples were taken to determine the activity of serum enzymes. To investigate the metabolism of Mo, Cd, Pb, Hg and Se, samples were taken from the heart, liver, lungs, kidneys, spleen, ovaries/testicles, entire digestive tract, adipose tissue, femur, hair, faeces and urine. Carrot had significantly higher digestibility for all nutrients than the rabbit concentrate. Carrot samples of high Pb content had the lowest digestibility of crude protein. The microelements differed in their rate of accumulation in the organs examined: Mo and Cd accumulated in the kidneys, Pb in the kidneys, liver, bones and lungs, Hg in the kidneys and liver, while Se in the liver, kidneys and heart. The proportions of microelements eliminated from the body either via the faeces and urine (Mo 80.18% and Se 47.41%) or via the faeces (Cd 37.86%, Pb 66.39%, Hg 64.65%) were determined. Pathohistological examination revealed that the rate of spermatogenesis was reduced in the Mo, Cd, Pb and Hg groups compared to the control. Lead, Cd and Hg intake resulted in a considerable decrease in gamma-glutamyltransferase (GGT) and in an increase of alkaline phosphatase (ALP) activity because of damages to the kidneys and bones. All experimental treatments decreased the activity of cholinesterase (CHE) because of lesions in the liver.

scholarly journals The physiological basis for genetic variation in water use efficiency and carbon isotope composition in Arabidopsis thaliana

2013 ◽  
Vol 119 (1-2) ◽  
pp. 119-129 ◽  
Author(s):  
Hsien Ming Easlon ◽  
Krishna S. Nemali ◽  
James H. Richards ◽  
David T. Hanson ◽  
Thomas E. Juenger ◽  
...  
Keyword(s):  
Arabidopsis Thaliana ◽  
Genetic Variation ◽  
Water Use Efficiency ◽  
Carbon Isotope ◽  
Water Use ◽  
Isotope Composition ◽  
Carbon Isotope Composition ◽  
Physiological Basis ◽  
Use Efficiency

scholarly journals Evolution and evolvability: celebrating Darwin 200

2008 ◽  
Vol 5 (1) ◽  
pp. 44-46 ◽  
Author(s):  
John F.Y Brookfield
Keyword(s):  
Genetic Variation ◽  
Natural Selection ◽  
Time Scales ◽  
Evolutionary Change ◽  
Adaptive Mutation ◽  
Genetic Covariances ◽  
The Relationship ◽  
The Way

The concept of ‘evolvability’ is increasingly coming to dominate considerations of evolutionary change. There are, however, a number of different interpretations that have been put on the idea of evolvability, differing in the time scales over which the concept is applied. For some, evolvability characterizes the potential for future adaptive mutation and evolution. Others use evolvability to capture the nature of genetic variation as it exists in populations, particularly in terms of the genetic covariances between traits. In the latter use of the term, the applicability of the idea of evolvability as a measure of population's capacity to respond to natural selection rests on one, but not the only, view of the way in which we should envisage the process of natural selection. Perhaps the most potentially confusing aspects of the concept of evolvability are seen in the relationship between evolvability and robustness.

Effect of weeds and nitrogen fertiliser on yield and grain protein concentration of wheat

1996 ◽  
Vol 36 (4) ◽  
pp. 443 ◽  
Author(s):  
MG Mason ◽  
RW Madin
Keyword(s):  
Grain Yield ◽  
Weed Control ◽  
Dry Matter ◽  
Protein Concentration ◽  
The Other ◽  
Grain Protein ◽  
Dry Matter Yield ◽  
Wheat Grain ◽  
Grain Protein Concentration ◽  
Nitrogen Fertiliser

Field trials at Beverley (19911, Salmon Gums (1991; 2 sites) and Merredin (1992; 2 sites), each with 5 rates of nitrogen (N) and 3 levels of weed control, were used to investigate the effect of weeds and N on wheat grain yield and protein concentration during 1991 and 1992. Weeds in the study were grasses (G) and broadleaf (BL). Weeds reduced both vegetative dry matter yield and grain yield of wheat at all sites except for dry matter at Merredin (BL). Nitrogen fertiliser increased wheat dry matter yield at all sites. Nitrogen increased wheat grain yield at Beverley and Merredin (BL), but decreased yield at both Salmon Gums sites in 1991. Nitrogen fertiliser increased grain protein concentration at all 5 sites-at all rates for 3 sites [Salmon Gums (G) and (BL) and Merredin (G)] and at rates of 69 kg N/ha or more at the other 2 sites [Beverley and Merredin (BL)]. However, the effect of weeds on grain protein varied across sites. At Merredin (G) protein concentration was higher where there was no weed control, possibly due to competition for soil moisture by the greater weed burden. At Salmon Gums (G), grain protein concentration was greater when weeds were controlled than in the presence of weeds, probably due to competition for N between crop and weeds. In the other 3 trials, there was no effect of weeds on grain protein. The effect of weeds on grain protein appears complex and depends on competition between crop and weeds for N and for water at the end of the season, and the interaction between the two.

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