Segregation Among Test-Cross Progeny Suggests That Two Complementary Dominant Genes Explain the Difference Between Ascites-Resistant and Ascites-Susceptible Broiler Lines

Germination percentage and germination rate were examined in two melon accessions differing in their ability to germinate under low temperature and in their reciprocal F1, F2, and BC1 progeny. The seedcoat structure, pressure force required for seedcoat splitting, and the response to hilum sealing of the reciprocal F1s were examined as well. The purpose of this study was to elucidate the effects of embryonic genotype and seedcoat characteristics on the ability of melon seeds to germinate under low temperature. The results of the study point out that both components are strongly involved in low-temperature germination. The cold tolerant parent, ‘Persia 202’ (P202), germinated greater than 90% at 15 °C, whereas the cold-sensitive parent, ‘Noy Yizre'el’ (NY), did not germinate at all. The P202 × NY F1 and the reciprocal F2 germinated 80% to 90%, whereas the NY × P202 F1 germination percentage was only 71%. Backcrosses of the reciprocal F1 to the parents revealed that if the cross was to the tolerant one, the seeds germinated greater than 90%, but if the F1s were backcrossed to the sensitive parent, the seeds had only 56% to 60% germination. Data collected suggest that several dominant genes are carried by P202 for low-temperature germination. On the other hand, the difference in germination percentages between the reciprocal F1 demonstrates that the different seedcoats also play a role.

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Revelation of Epistasis through Triple Test Cross (TTC) Analysis in Rice (Oryza sativa L.)

Indian Journal of Agricultural Research ◽

10.18805/ijare.a-5688 ◽

2021 ◽

Author(s):

J. Johnny Subakar Ivin ◽

Y. Anbuselvam ◽

Maddi sivakumar ◽

M. Surendhar ◽

S. Keerthana

Keyword(s):

Oryza Sativa L ◽

Block Design ◽

Components Of Variance ◽

Triple Test Cross ◽

Test Cross ◽

Study Materials ◽

Triple Test ◽

Panicle Number ◽

Wide Range ◽

The Difference

Background: An investigation was performed to identify epistasis, additive, dominance components of genetic variation and yield and yield variability attributing characteristics by triple test cross testing involving three testers (P1, P2 and F1) and ten rice lines.Methods: The study materials consisted of F1 seeds of three crosses, involving six parents namely, ASD16, ADT47, ASD18, CO51, TKM9 and MTU 7029. They are evaluated in randomized complete block design with three replications. Observations were reported for seven traits, namely plant height, number of tillers per plant, number of productive tillers per plant, length of panicle, number of grains per panicle, weight of 1000 grains and yield of grain per plant on five randomly selected plants per replication.Result: The segregating population of three crosses exhibited wide range of variability for most of the traits. The difference between GCV and PCV was low for most of the characters indicated less influence of environment. Among the three crosses ASD18 x CO15 recorded high percent of heritability and genetic advance for grain yield per plant. The estimate of total epistasis revealed that i type of epistasis (additive x additive) was highly significant for number of tillers per plant, number of productive tillers per plant, panicle length and 1000 grain weight. The effect of the additive (D) variance was very important for all the traits except the number of grains per panicle. Across all traits, the degree of dominance (H / D)1/ 2 was less than unity ( less than 1) suggesting, partial of dominance. Since, the pre dominance component of epistasis in autogamous crop is additive x additive (i type), it was suggested that the selection may be post ponded to later generation until all the non-additive components of variance has been mitigated to additive components.

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Genetics of a difference in cuticular hydrocarbons between Drosophila pseudoobscura and D. persimilis

Genetics Research ◽

10.1017/s0016672300034005 ◽

1996 ◽

Vol 68 (2) ◽

pp. 117-123 ◽

Cited By ~ 34

Author(s):

Mohamed A. F. Noor ◽

Jerry A. Coyne

Keyword(s):

Cuticular Hydrocarbons ◽

X Chromosome ◽

Genetic Basis ◽

Species Difference ◽

Sexual Isolation ◽

The Other ◽

Drosophila Pseudoobscura ◽

The Difference ◽

Dominant Genes

SummaryWe identify a fixed species difference in the relative concentrations of the cuticular hydrocarbons 2-methyl hexacosane and 5,9-pentacosadiene in Drosophilapseudoobscura and D. persimilis, and determine its genetic basis. In backcross males, this difference is due to genes on both the X and second chromosomes, while the other two major chromosomes have no effect. In backcross females, only the second chromosome has a significant effect on hydrocarbon phenotype, but dominant genes on the X chromosome could also be involved. These results differ in two respects from previous studies of Drosophila cuticular hydrocarbons: strong epistasis is observed between the chromosomes that producethe hydrocarbon difference in males, and the difference is apparently unrelated to the strong sexual isolation observed between these species.

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Inheritance of plumage colour in the F1 and test cross progeny of Japanese quail

Nigerian Journal of Animal Production ◽

10.51791/njap.v47i3.158 ◽

2020 ◽

Vol 47 (3) ◽

pp. 212-224

Author(s):

T. I. Adedoyin ◽

T. R. Fayeye ◽

O. J. Amao

Keyword(s):

Japanese Quail ◽

Plumage Colour ◽

Wild Type ◽

Phenotypic Effect ◽

Chi Square ◽

Type Allele ◽

Test Cross ◽

Dominant Phenotype ◽

Recessive Genes ◽

Test Cross Progeny

Recessive genes produced its phenotypic effect only when its allele is identical while the dominant ones produced its effect either with identical or dissimilar alleles. This study was conducted to determine the mode of inheritance of plumage colour in Japanese quail flock in Nigeria, using the Manchurian Gold (MG), Pharaoh (PH) and Panda White (PW) plumage types. All possible crosses were made among the three colour variants making a total of nine mating groups. A total number of 2,348 F1 chicks and 1,563 test cross progeny obtained from the incubated eggs were classified and counted by their down colour into observable plumage colour groups. The expected phenotypic ratios of the F1 and test cross progeny were computed based on the assumption that parents that were homozygous for a particular plumage colour breed true. The results revealed that the Pharaoh plumage quails carry the wild-type allele (Wb) in homozygous form or in heterozygous with the Panda White (wb) allele. The Manchurian gold plumage quails carry the Manchurian Gold-type allele (Wb+) in heterozygous with either Wb or wb. All the Panda White chicks were homozygous for the wb allele, which was recessive to both Wb and Wb+ alleles. The Chi-square results confirm the heterozygousity of the dominant phenotype in the test crosses. It can be concluded that inheritance of plumage colour is controlled by autosomal genes with dominant hierarchy of MG> PH> PW (Wb+ >Wb>wb).

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The Origin of the Moon

Symposium - International Astronomical Union ◽

10.1017/s0074180900178209 ◽

1962 ◽

Vol 14 ◽

pp. 149-155 ◽

Cited By ~ 1

Author(s):

E. L. Ruskol

Keyword(s):

Chemical Composition ◽

Solar System ◽

The Moon ◽

The Earth ◽

The Difference ◽

Origin Of The Moon

The difference between average densities of the Moon and Earth was interpreted in the preceding report by Professor H. Urey as indicating a difference in their chemical composition. Therefore, Urey assumes the Moon's formation to have taken place far away from the Earth, under conditions differing substantially from the conditions of Earth's formation. In such a case, the Earth should have captured the Moon. As is admitted by Professor Urey himself, such a capture is a very improbable event. In addition, an assumption that the “lunar” dimensions were representative of protoplanetary bodies in the entire solar system encounters great difficulties.

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Influence of Cell Wall Composition on the Fossilisation of Bacteria and the Implications for the Search for Early Life Forms

International Astronomical Union Colloquium ◽

10.1017/s0252921100015025 ◽

1997 ◽

Vol 161 ◽

pp. 491-504 ◽

Cited By ~ 3

Author(s):

Frances Westall

Keyword(s):

Cell Wall ◽

Life Forms ◽

Cation Binding ◽

Positive Bacterium ◽

Gram Positive ◽

Gram Positive Bacteria ◽

Transmission Electron ◽

Hydrothermal Sediments ◽

Identification Of Bacteria ◽

The Difference

AbstractThe oldest cell-like structures on Earth are preserved in silicified lagoonal, shallow sea or hydrothermal sediments, such as some Archean formations in Western Australia and South Africa. Previous studies concentrated on the search for organic fossils in Archean rocks. Observations of silicified bacteria (as silica minerals) are scarce for both the Precambrian and the Phanerozoic, but reports of mineral bacteria finds, in general, are increasing. The problems associated with the identification of authentic fossil bacteria and, if possible, closer identification of bacteria type can, in part, be overcome by experimental fossilisation studies. These have shown that not all bacteria fossilise in the same way and, indeed, some seem to be very resistent to fossilisation. This paper deals with a transmission electron microscope investigation of the silicification of four species of bacteria commonly found in the environment. The Gram positiveBacillus laterosporusand its spore produced a robust, durable crust upon silicification, whereas the Gram negativePseudomonas fluorescens, Ps. vesicularis, andPs. acidovoranspresented delicately preserved walls. The greater amount of peptidoglycan, containing abundant metal cation binding sites, in the cell wall of the Gram positive bacterium, probably accounts for the difference in the mode of fossilisation. The Gram positive bacteria are, therefore, probably most likely to be preserved in the terrestrial and extraterrestrial rock record.

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Structuring, Motions and Shapes of Corona Emission Line Profiles

International Astronomical Union Colloquium ◽

10.1017/s0252921100025720 ◽

1994 ◽

Vol 144 ◽

pp. 421-426

Author(s):

N. F. Tyagun

Keyword(s):

Emission Line ◽

Filling Factor ◽

Direct Relationship ◽

Coronal Plasma ◽

Line Of Sight ◽

Line Profiles ◽

The Difference ◽

Yellow Line ◽

Red Line

AbstractThe interrelationship of half-widths and intensities for the red, green and yellow lines is considered. This is a direct relationship for the green and yellow line and an inverse one for the red line. The difference in the relationships of half-widths and intensities for different lines appears to be due to substantially dissimilar structuring and to a set of line-of-sight motions in ”hot“ and ”cold“ corona regions.When diagnosing the coronal plasma, one cannot neglect the filling factor - each line has such a factor of its own.

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Difference Fourier Analysis of Glucose Embedded and Frozen Hydrated Purple Membrane

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100053164 ◽

1982 ◽

Vol 40 ◽

pp. 74-75

Author(s):

Jules S. Jaffe ◽

Robert M. Glaeser

Keyword(s):

Purple Membrane ◽

Data Set ◽

High Resolution Data ◽

X Ray ◽

X Ray Crystallography ◽

Fourier Techniques ◽

Versus Protein ◽

The Difference ◽

Difference Fourier ◽

Ideal Method

Although difference Fourier techniques are standard in X-ray crystallography it has only been very recently that electron crystallographers have been able to take advantage of this method. We have combined a high resolution data set for frozen glucose embedded Purple Membrane (PM) with a data set collected from PM prepared in the frozen hydrated state in order to visualize any differences in structure due to the different methods of preparation. The increased contrast between protein-ice versus protein-glucose may prove to be an advantage of the frozen hydrated technique for visualizing those parts of bacteriorhodopsin that are embedded in glucose. In addition, surface groups of the protein may be disordered in glucose and ordered in the frozen state. The sensitivity of the difference Fourier technique to small changes in structure provides an ideal method for testing this hypothesis.

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Destruction of Actin Filaments by Osmium Tetroxide

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100079772 ◽

1977 ◽

Vol 35 ◽

pp. 466-467

Author(s):

P. Maupin-Szamier ◽

T. D. Pollard

Keyword(s):

Actin Filaments ◽

Time Course ◽

Osmium Tetroxide ◽

Rabbit Muscle ◽

Muscle Actin ◽

Sodium Phosphate Buffer ◽

Transmission Electron ◽

The Difference ◽

Rates Of Decay ◽

Short Time

We have studied the destruction of rabbit muscle actin filaments by osmium tetroxide (OSO4) to develop methods which will preserve the structure of actin filaments during preparation for transmission electron microscopy.Negatively stained F-actin, which appears as smooth, gently curved filaments in control samples (Fig. 1a), acquire an angular, distorted profile and break into progressively shorter pieces after exposure to OSO4 (Fig. 1b,c). We followed the time course of the reaction with viscometry since it is a simple, quantitative method to assess filament integrity. The difference in rates of decay in viscosity of polymerized actin solutions after the addition of four concentrations of OSO4 is illustrated in Fig. 2. Viscometry indicated that the rate of actin filament destruction is also dependent upon temperature, buffer type, buffer concentration, and pH, and requires the continued presence of OSO4. The conditions most favorable to filament preservation are fixation in a low concentration of OSO4 for a short time at 0°C in 100mM sodium phosphate buffer, pH 6.0.

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Antiphase Boundaries in Ordered Ni3FE Crystals

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s042482010006221x ◽

1969 ◽

Vol 27 ◽

pp. 62-63

Author(s):

Y. H. Liu

Keyword(s):

Domain Size ◽

Antiphase Domain ◽

X Ray Diffraction ◽

X Ray ◽

Hardening Mechanism ◽

Superlattice Structure ◽

Disordered Phase ◽

Domain Boundaries ◽

Atomic Scattering ◽

The Difference

Ordered Ni3Fe crystals possess a LI2 type superlattice similar to the Cu3Au structure. The difference in slip behavior of the superlattice as compared with that of a disordered phase has been well established. Cottrell first postulated that the increase in resistance for slip in the superlattice structure is attributed to the presence of antiphase domain boundaries. Following Cottrell's domain hardening mechanism, numerous workers have proposed other refined models also involving the presence of domain boundaries. Using the anomalous X-ray diffraction technique, Davies and Stoloff have shown that the hardness of the Ni3Fe superlattice varies with the domain size. So far, no direct observation of antiphase domain boundaries in Ni3Fe has been reported. Because the atomic scattering factors of the elements in NijFe are so close, the superlattice reflections are not easily detected. Furthermore, the domain configurations in NioFe are thought to be independent of the crystallographic orientations.

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