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1.
The authors calculate the cross-section with one-loop electroweak corrections to the process in the standard model(SM),including virtual corrections and soft photon radiative correction.They discuss the relations between the cross-sections in tree level(and one-loop corrected cross sections) and center-mass energy s in the luminosity measuring ranges of GLC. 相似文献
2.
In the Lorentz Invariable Coupling Model of interaction between pion and nucleon (antinucleon), by applying the complex function integral method, the authors have strictly calculated the one-dimensional integral, which is derived from the great momentum integral limit, of the renormalized finite quantity of one-loop propagator and chain propagator in the momentum renormalization scheme and gained the finally strict analysis result. At the last, they have detailed these numerical results of the renormalized finite quantity, and also done the relevant discussion about these minute radiation corrections. 相似文献
3.
In the minimum electromagnetism coupling model of interaction between photon and electron(antielectron),Feynman convergence integral method is often used to deal with the finite quantity of one-loop correction scheme.After analyzing,discussing and researching the method,a new method is found.That is the great moment integral limitation method.Through the method,the relative result is obtained. 相似文献
4.
When light spreads in gravitational wave, its frequency is changed. Usually considering frequency gravitational shift, the rest mass of the photon is neglected. According to Proca equations of weight electromagnetic wave the authors investigate the Frequency shift of Proca light. The results of numerical estimation show that frequency shift of the photon has a small change when considering the rest mass of the photon and it is not detected at present experimental condition. 相似文献
5.
Catherine Dogimont Angelica Bussemakers Jérôme Martin Sofiane Slama Hervé Lecoq Michel Pitrat 《Euphytica》1997,96(3):391-395
The genetic control of resistance to cucurbit aphid-borne yellows luteovirus (CABYV) in Cucumis melo L. was studied in three
progenies obtained from the cross between a resistant Indian line, PI 124112, and a susceptible cultivar of Charentais type,
Védrantais. An F2 progeny and recombinant inbred lines were screened respectively in 1993 and 1995 under natural infection
conditions in open field at Montfavet, France whereas the back cross (PI 124112 × F1) was inoculated by viruliferous Myzus
persicae in controlled conditions. ELISA was used for assessing degree of virus multiplication in the plants resistance. In
the three trials performed, segregation analysis were consistent with the hypothesis that the resistance to CABYV in PI 124112
is conferred by two independent complementary recessive genes, for which the symbols cab-1 and cab-2T are proposed.
This revised version was published online in July 2006 with corrections to the Cover Date. 相似文献
6.
Yield and its components (stem-, leaf- and top-yield) were analyzed in a population derived from the cross between F1.1 andF1.7
entries of Miscanthus sinensisAnders. Both lines are offspring of the cross between MS-90-2 and MS-88-110. The aim of this work was to identify QTLs for
yield and its components suitable to develop a Marker Aided Selection (MAS) program in M. sinensis.QTL analyses were performed using a previous linkage map based on RAPD markers which was constructed using a new mapping
strategy named ‘offspring cross’ that is useful for mapping in forest and fruit trees. The MapQTL 4.0 package was used to
perform QTL analyses. Twenty potential QTLs were detected over two years of analyses. Out of these, 6 were associated with
yield,8 with stem-yield, 2 with leaf-yield and 4with top-yield. These results constitute an initial step to develop a MAS
program for biomass production.
This revised version was published online in July 2006 with corrections to the Cover Date. 相似文献
7.
A new method for screening wheat for boron tolerance has been developed to overcome the problems of methods used in the past.
Seedlings were grown for 10 days while suspended over B-rich solutions. Their root lengths were then measured as an index
of tolerance. Five varieties of wheat were screened at seven concentrations of B. Results were obtained more quickly and easily
than from the alternative methodologies and compared favourably. Screening of 128 doubled haploid lines from a cross between
Halberd and (Wl*MMC) suggested that transgressive segregation had occurred.
This revised version was published online in August 2006 with corrections to the Cover Date. 相似文献
8.
Anther culture was applied as a method to develop the essential components of a cytoplasmic male sterility hybrid system in
rye (Secale cereale L.). These components are the male sterile seed parent (A line), its isogenic maintainer counterpart (B
line) and the restorer pollen parent (R line). Australian rye cultivars were crossed reciprocally to the cultivar ‘Luchs’
which carries the Pampa male sterile cytoplasm (cms-P). Anthers of the F1s in the cms-P cytoplasm (primary cross) and their
reciprocals in the normal cytoplasm (reciprocal cross) were cultured in a modified C17 medium. Male sterile and male fertile
doubled haploids were obtained from the anther culture of the F1s in the cms-P cytoplasm. Testcrosses indicated that the male
sterile doubled haploids were A lines and the male fertile doubled haploids were R lines (restorers). The anther culture of
genotypes in the normal cytoplasm (reciprocal cross) gave all male fertile doubled haploids. Testcrosses indicated that the
male fertile doubled haploids were R lines (restorers) in the normal cytoplasm. The expected maintainer B lines were not identified
because of the limited number of doubled haploids obtained from the anther culture of reciprocal crosses. Experimental single
cross hybrids between male sterile and restorer male fertile doubled haploids showed high levels of heterosis. The results
of this study have significant economic implications especially in the production of hybrids in several species.
This revised version was published online in July 2006 with corrections to the Cover Date. 相似文献
9.
J. Robinson 《Euphytica》1999,110(3):175-180
A half-diallel was made between five six-rowed Nordic spring barleys to study the genetics of resistance to net blotch. Twenty-five
doubled-haploid (DH) lines from each cross and the parents were sown in hill plots in Finland in 1997 and 1998. The plots
were artificially inoculated with Pyrenophora teres Drechs. f. teres Smedeg. and assessed for resistance to net blotch. There were statistically significant differences in resistance of the
five parents to net blotch. General combining ability (GCA) of the parents and specific combining ability (SCA) effects in
the progeny were statistically significant in both years, but GCA effects predominated. Evidence for additive epistasis was
minimal. Progeny of a particular cross were less resistant to net blotch than the better parent. The most resistant progeny
were derived from the cross between the two most resistant parents, Pohto and WW7977, and resistance was governed by at least
eleven effective factors. Narrow sense heritability estimates for resistance to net blotch were high during both years (0.84–0.99).
It appears that net blotch resistance of progeny from crosses can be largely predicted from reactions of the parents. Quantitative
resistance to net blotch can be further advanced by identification and incorporation of superior parents, from a screening
such as reported here, into a recurrent selection breeding programme.
This revised version was published online in August 2006 with corrections to the Cover Date. 相似文献
10.
Pollen germination and pollen tube growth were studied in the cross Erucastrum abyssinicum × Brassica oleracea. 25 per cent
ovules showed pollen tube entry into the micropyle 5 days after pollination. Embryos did not grow beyond the globular or heart-shaped
stage. Thus post-fertilization barriers prevent hybridization in this cross. Sequential culture of ovaries and ovules 10 days
after pollination helped rescue globular embryos. Three hybrids were obtained. All the hybrids flowered in vitro. Pollen fertility
was 6.5 per cent. Leaf esterase and peroxidase isozymes confirmed the hybrid nature. Meiotic metaphase in the pollen mother
cells showed 25 chromosomes. The presence of up to 9 bivalents and a quadrivalent indicates high homology between the two
genera. The intergeneric hybrids have been multiplied using nodal segment culture. They are a source for obtaining cms cole
crops and widening the gene pool of B. oleracea.
This revised version was published online in July 2006 with corrections to the Cover Date. 相似文献
11.
The heritability of tolerance of wheat F3 lines to competition from annual ryegrass (Lolium rigidum), and its relationship to morphological traits, were determined using crosses between wheat cultivars with good and poor
competitive ability. Forty F2-derived F3 lines from a cross between two late flowering varieties (Machete × Spear) and 40 from a cross between early flowering varieties
(Wilgoyne × Gutha) were grown in the field with and without annual ryegrass. There was significant genetic variation between
lines within each of the two populations in a number of aspects of plant growth and development, including yield in monoculture.
The estimates of heritability for % yield loss due to competition were 0.25 and 0.57 in the two crosses respectively, indicating
that selection for high tolerance to competition in the F3 generation or later should be effective. Fairly strong relationships between height and % yield loss and between leaf length
and % yield loss suggest that these may be useful auxiliary traits when selecting for low % yield loss. However, differences
between crosses in the magnitude and sign of genetic and phenotypic correlation between traits indicate that competitive ability
is a complex character influenced by many factors.
This revised version was published online in August 2006 with corrections to the Cover Date. 相似文献
12.
To maximize the extent of polymorphism within a mapping population wide crosses are often made, frequently resulting in distorted
segregation. Two parents used in the crosses in this study contained ca 50% from wild lentil genome (Lens culinaris ssp. Orientalis).
We investigated the use of random amplified polymorphic DNA (RAPD) in the lentil (Lens culinaris Med.), for genetic mapping
and testing for segregation distortion in F2 populations. In cross 1, 83% of the RAPD markers showed segregation distortion, which was also observed for isozyme and morphological
loci. By contrast, in cross 2, there was little (10%) segregation distortion. Out of 390 primers tested, 116 primers (29.7%)
yielded 192 polymorphic fragments between parents of cross 2. This polymorphism was confirmed as reproducible. Seventy-eight
segregating loci were analyzed for linkage, at a LOD score > 3.0, resulted in 28 RAPD, one RFLP, one morphological and three
oligonucleotide markers, which were assigned to 9 linkage groups spanning 206 cM. Clearly, in lentil RAPD markers were valuable
for genetic mapping and evaluation of segregation distortion.
This revised version was published online in July 2006 with corrections to the Cover Date. 相似文献
13.
The location and effects of genomic regions for rust resistance in sorghum were determined. One hundred and sixty recombinant
inbreds, which derived from a cross between QL39 and QL41, were used as a segregating population for genome mapping and rust
resistance evaluation. Phenotypic data were collected in replicated field trials in two years. Interval mapping and non-parametric
mapping identified four regions, each in a separate linkage group, associated with rust resistance. The region with the largest
effect on rust resistance is on linkage group 10; it accounted for 40% of the total phenotypic variation.
This revised version was published online in July 2006 with corrections to the Cover Date. 相似文献
14.
The melon (Cucumis melo) plant introduction PI 414723 was observed to segregate for resistance after inoculation with a highly
virulent non-aphid-transmissible strain of zucchini yellow mosaic potyvirus (ZYMV-NAT). By self-pollination of selected resistant
plants, the percentage of resistant plants increased in successive generations until nearly 100% in the S7 progeny. A reciprocal cross was made between a resistant S5 plant of PI 414723 and a plant of the susceptible cultivar Dulce. Parental-, filial-, and backcross- generation plants were
inoculated with ZYMV-NAT. One-half of the F1 plants, regardless of the direction of the cross, were resistant, indicating that the PI 414723 individual used for crossing
was heterozygous. The F2 generation obtained by self-pollination of resistant F1 plants segregated to resistant and susceptible in accordance with a 27:37 ratio, indicating that, in this cross, three complementary
dominant genes are needed for resistance to be expressed. The resistance to ZYMV carried by PI 414723 is oligogenic with the
number of genes observed to segregate in crossing depending on the genotype of the susceptible parent.
This revised version was published online in July 2006 with corrections to the Cover Date. 相似文献
15.
Effectiveness of three-way crossing for the breeding of yellow-flowered evergreen azalea 总被引：2，自引：1，他引：1
For the purpose of obtaining yellow-flowered evergreen azaleas, single and three-way interspecific crosses between evergreen
azaleas and Rhododendron japonicum f. flavum were compared. In single cross, although many seeds were obtained from R. eriocarpum
× R. japonicum f. flavum, the seedlings from immature ovule were albino or pale-green plants. They were withered away at acclimation.
In R. kiusianum × R. japonicum f. flavum, green seedlings were observed, but number of ovules contained in one capsule was
very small. In three-way cross, (R. kiusianum × R. eriocarpum) × R. japonicum f. flavum, many viable seeds were contained
in one capsule, and about 15% of the seedlings were green leaf colored. These results suggest that three-way cross is one
of the useful breeding methods for creating the new yellow-flowered evergreen azalea. Isozyme analysis revealed that most
of seedlings were zygotic origin without distinction of their leaf colors, but some green seedlings indicated the same genotypes
as the seed parents. Therefore, it is important to confirm hybridity of the seedlings by isozyme technique.
This revised version was published online in August 2006 with corrections to the Cover Date. 相似文献
16.
Genetic diversity in apricot cultivars based on AFLP markers 总被引：5，自引：0，他引：5
A set of cultivars used as genitors in apricot breeding programs aimed at introducing sharka resistance were examined by AFLP
molecular marker analysis. The markers obtained indicated that apricot cultivars resistant to sharka were related to the European
cultivars, but they potentially share a common ancestor donor of sharka outside of the European group. Segregation of AFLP
and RAPD markers has been tested in two progenies of two crosses, one between a resistant and a susceptible cultivar and one
between two susceptible accessions. The heterozygozity of families obtained from crosses between resistant and susceptible
cultivars is similar to those obtained from other self-incompatible Prunus species. On the other hand, heterozygosity of a
progeny obtained from a cross between European susceptible cultivars was very low. The usefulness of the information provided
by AFLPs for apricot breeding programs is discussed.
This revised version was published online in August 2006 with corrections to the Cover Date. 相似文献
17.
M. Abdullah Yousuf Akhond M. Abul Hossain Molla M. Obaidul Islam Mohammad Ali 《Euphytica》2000,114(3):175-180
Interspecific cross compatibility between cultivated and wild okra (Abelmoschus esculentus and A. moschatus) and pollen tube growth behaviour in the crosses among a local cultivar of A. esculentus, A. moschatus and their F1s were studied. Fruit set was observed in all the crosses except one and seed setting was absent in two of the crosses which
set fruit. All seed produced were shrivelled but F1 plants were obtained from two crosses where cultivated okra was used as the seed parent. The F1 plants were perennial in nature with very low pollen viability and seed set. A high percentage of pollen germination and
profuse pollen tube penetration in the style were observed in the cross A. esculentus × A. moschatus but low pollen tube penetration with abnormal pollen tubes was observed in the reciprocal cross. The number
of pollen tubes was very low but they appeared to be normal in the backcross A. esculentus × F1, but were generally abnormal in the reciprocal cross. Both pre- and postzygotic barriers seemed to occur in crosses between
the two species. The present studies indicate that these barriers can be overcome and desirable characters from A. moschatus transferred to cultivated okra using conventional hybridisation techniques.
This revised version was published online in July 2006 with corrections to the Cover Date. 相似文献
18.
The extent and distribution of incompatibility between gene pools (Mesoamerican and Andean) and evolutionary classes (wild,
landrace and bred) of the common bean (Phaseolus vulgaris) was explored by seeking anomalous values of highly heritable quantitative traits in the progeny of crosses. Clear incompatibility
(no progeny or sterile or deformed progeny) was shown by 28 crosses in a 12-parent wild × bred diallel cross, and 37 crosses
in a 12-parent landrace × bred diallel cross. Incompatibility was particularly common in the progeny of certain genotypes,
but was not consistently associated with the division between gene pools or evolutionary classes. When crosses showing clear
incompatibility were eliminated from the data, days to flowering, number of seeds per pod, log (weight per seed) and seed
roundness in the F1 generation gave a good fit to an additive-dominance model, confirming that there is no overall tendency to incompatibility
between the gene pools. There was a division between the gene pools with regard to log (weight per seed), as expected, but
there was no such division, with regard either to the means of the parent lines or the distribution of the statistics V
r and W
r (which indicate the distribution of dominant alleles between genotypes), for the other quantitative variables. Differences
between reciprocal crosses were strikingly widespread, and appeared generally to be due to cytoplasmic effects or cytoplasmic
× nuclear interactions rather than maternal effects, indicating that the direction in which a cross is made may have a perceptible
effect on the progeny that can be obtained from it.
This revised version was published online in July 2006 with corrections to the Cover Date. 相似文献
19.
Cytoplasmic effects have been occasionally implicated in the inheritance of several traits in oilseed rape (Brassica napus L.), including linolenic acid concentration (18:3) in the oil. It is important that these be considered when choosing the
direction of cross for producing new breeding populations. To study this phenomenon, a reciprocal cross was made between two
genotypes of oilseed rape, Reston and LL09, which differed for their erucic and linolenic acid concentrations in the seed
oil. Two DH populations, which were produced by microspore culture from reciprocal F1 plants, were evaluated in the growth room for one generation and in the field at two locations in Southern Ontario in 1993and
1994. Field notes were taken on days to flower, days to maturity,plant lodging, plant height and, seed quality traits. In
the growth room study, the phenotypic distribution of 18:3 differed significantly between the two reciprocal DH populations.
In the field, significant reciprocal differences between the population means were detected for 18:3,flowering date and protein
content in both years and for days to maturity and oil content in 1993 only. To further study the parental lines,chloroplast
(cp) and mitochondrial (mt) DNA from parental lines were isolated and subjected to RFLP and RAPD analysis. Several random
primers revealed reproducible DNA polymorphism (RAPD) between the parental mt DNA. It is concluded that the direction of cross
should be taken into consideration by oilseed rape breeders relying solely on doubled haploids for developing genotypes with
modified seed quality traits in Brassica napus L.
This revised version was published online in July 2006 with corrections to the Cover Date. 相似文献
20.
The genetic nature of bacterial wilt resistance in tomato was studied in two crosses based on the number of days of survival
(quantitative) in the field before the appearance of wilt symptoms. Significant differences were observed between generation
means in both crosses (LA 1421 × Cascade and LA 1421 × Caraibo). This study indicates that resistance identified in Lycopersicon
esculentum var. cerasiforme LA 1421 may be different from that derived from L. pimpinellifolium. However, the genetic mechanism
seems to be complex with a duplicate form of epistasis. Results suggest that selection for resistance from crosses between
LA 1421 and Cascade should preferably be delayed until a high level of fixation of genes is attained. The variation observed
in the F2 and BC2 progeny of the Caraibo cross, suggested that genetic combination between the two resistance sources can lead to higher levels
of resistance.
This revised version was published online in July 2006 with corrections to the Cover Date. 相似文献