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1.
The influence of modifier genes on the intensity and stability of self-incompatibility in cabbage 总被引：2，自引：0，他引：2
Summary Four inbred cabbage lines have been derived from a single parental plant through several generations of selfing. Two inbreds have been found homozygous for an S
1 allele while the other two are each homozygous for S
2. Each inbred is self-incompatible, cross-incompatible with the inbred carrying the same S allele, and fully cross-compatible with inbreds carrying the other S allele. The S
1 and S
2 pairs of inbreds were each found to consist of one inbred with very high self-incompatibility (mean seed set of 0.15–0.25 seeds per pod) and one inbred with less intense self-incompatibility (mean seed set of 1.25–1.70 seeds per pod). For the S
1 pair, flower to flower and plant to plant variation in seed set per pod was much larger for the less incompatible inbred that for the highly incompatible inbred. Further, incompatibility expression of the less incompatible inbred was influenced by temperature variation while that of the highly incompatible inbred was stable under different temperature regimes. The F1 between the two inbreds of high and low incompatibility with the common S
1 allele behaved like the less incompatible parent. F2 plants showed intermediate intensities of selfincompatibility as well as variation for both lesser and greater intensities than those exhibited by the parents. The variations of self-compatibility and the sensitivity to environmental differences are considered to be conditioned by genes which modify incompatibility expression of the S alleles. 相似文献
2.
Summary Fourteen cultivars, one F1-hybrid and one half-wild type (Cind) of sweet pepper were tested on resistance to glasshouse whitefly. Several mutually significant levels of resistance were found. Most resistant appeared to be California Wonder, Severka M, Korál and Yolo Wonder. During the test sweet pepper plants were infested both with whiteflies and their parasite — Encarsia formosa, which caused the blackening of whitefly puparia. The blackened puparia are easily seen, enabling an easier and more rapid evaluation of the number of puparia present. 相似文献
3.
H. de Haan 《Euphytica》1952,1(1):60-61
Summary The English abstracting journal Plant Breeding Abstracts gives a satisfactory synopsis of books on plant breeding and of articles in this field that have appeared in general and professional journals.In the above survey are mentioned the following periodicals: Sveriges Utsädesföreningstidskrift (1891 ), Zeitschrift für Pflanzenzüchtung (1913 ), Der Züchter (1929 ), Agri Hortique Genetica (1943 ), Indian Journal of Genetics and Plant Breeding (1941 ), Melhoramento (1948 ), Annales de l'Amélioration (1951 ) and Euphytica, Netherlands Journal of Plant Breeding (1952 ).
Vaktijdschriften op het gebied van de plantenveredeling相似文献
4.
F. P. Ferwerda 《Euphytica》1962,11(3):221-228
A sufficiently variable rye population was subjected to one cycle of recurrent selection for combining ability in order to ascertain whether this complex property can be repatterned.Some hundreds of clones derived from this population were toperossed to an other unrelated variety used as tester. Through visual selection, more than half of these clones were rejected. The topcross progenies of the remaining clones were subjected to a comparative test whereby, as was to be expected, a considerable degree of variability was demonstrated. From the best 10% and the poorest 10% that is from those which surpassed the general average by at least 1.5 standard deviation units or remained below that average by at least 1.5 , narrowed populations were built up. This was done with the aid of reserve seed which in the year in which the top cross was made had been obtained from these clones, either through compulsory selfpollination or by allowing the clones to fertilize each other in isolation. The two subpopulations obtained through selection in opposite directions further indicated as high and low were crossed en masse with the same tester variety as the first time. In addition a large number of randomly taken individuals from the high synthetic were cloned and toperossed to this common tester. On testing the top crosses carried out en masse, the high synthetics clearly yielded more than the low ones. In one trial it was even found that the high synthetic surpassed our standard variety Petkus by approximately 20%. It is possible, therefore, to segregate a population into two fractions of different combining ability.The optimistie pieture to be derived from the foregoing trials unfortunately is shaded by the results of the individual test crosses pointing to a shift of the frequency distribution in a negative sense in regard to the original population. The influence of the year may be mentioned as a possible cause of this contrast and also the fact that in the original population a close visual selection had been practised while those obtained from the synthetic resulting after one cycle were derived from individuals which had been taken entirely at random.
Samenvatting Een voldoende variabele roggepopulatic werd onderworpen aan één ronde van cyclisch herhaalde selectic op combinatie-geschiktheid ten einde na te gaan of deze complexe eigenschap kan worden vervormd.Enige honderden klonen voortgekomen uit deze populatie werden onderworpen aan een top-cross door een als tester gebruikt ander, onverwant, ras. Op grond van visuele selectie werd meer dan de helft van deze klonen afgekeurd. De proefkruisings-nakomelingschappen van de overblijvende klonen werden aan een vergelijkende toets onderworpen waarbij zoals viel te verwachten een aanzienlijke variabiliteit in opbrengstvermogen aan het licht trad. Uit de beste 10% en de slechtste 10%, d.w.z. die welke het algemeen gemiddelde met minstens 1,5 overschreden resp. daar minstens 1,5 beneden bleven, werden vernauwde populaties opgebouwd. Dit geschiedde met behulp van reservezaad dat in het jaar waarin de top-cross werd verricht van deze klonen was gewonnen, hetzij door gedwongen zelfbestuiving, hetzij door de klonen in isolatie aan onderlinge bestuiving over te laten. De op deze wijze verkregen twee in tegenovergestelde richting geselecteerde sub-populaties-aangeduid als high en low-werden en masse gekruist met hetzelfde tester ras als de eerste keer. Bovendien werd een groot aantal willekeurig uit het high syntheticum genomen individuen tot klonen gemaakt en onderworpen aan een top-cross door het zoëven genoemde tester ras. Bij de toetsing van en masse uitgevoerde proefkruisingen bleek de combinatie high x tester duidelijk meer op te brengen dan low tester. In een proef werd zelfs gevonden dat high x tester ons standaardras Petkus met ongeveer 20% overtrof. Het blijkt dus mogelijk een populatie te splitsen in 2 fracties van uiteenlopende combinatie-geschiktheid.Het optimistische beeld dat men uit de zo juist vermelde proeven krijgt wordt helaas verduisterd door de resultaten van de individuele proefkruisingen welke wijzen op een verschuiving van de frequentieverdeling in negatieve zin ten opzichte van de oorspronkelijke populatie. Als mogelijke oorzaken van deze tegenstelling kunnen worden aangewezen jaarinvloeden en tevens het feit dat onder de klonen uit de oorspronkelijke populatie een scherpe selectie op het oog werd toegepast terwijl die uit het na één cyclus verkregen syntheticum werden afgeleid van volkomen willekeurig genomen individuen.相似文献
5.
Yoshio Yoshida 《Euphytica》1964,13(1):65-74
If the expectation of the number of desirable mutants for equal size of X
2-populations decreases with decreasing number of plants per X
2-line, the one-plant-one-grain method (method C), the one-plant-two-grain method (method D), and the one-plant-three-grain method (method E), especially method C, would be disadvantageous in comparison with the improved ear-to-row method (method B) and the conventional ear-to-row method (method A).From theoretical considerations it can be shown that a probability of occurrence of an X
2-line containing desirable mutant (p
1) and a conditional probability of occurrence of such desirable mutant for each one of the plants in such an X
2-line (p
2) are not affected by the number of X
2-lines (m), but by the number of plants per X
2-line (n). Consequently, the expectation of the number of desirable mutants in an X
2-population, E(I), can be given by
E(I) = mp
1(1– q
2
n · n p
2/(1 –q
2
n) = mn p
1
p
2
where p
1+q
1=1 and p
2+q
2=1.Therefore, with respect to E(I), method A=B=C=D=E for equal size of X
2-populations. However, method ABE>D>C for different sizes of X
2-populations.Most of this work was carried out in the National Institute of Agricultural Sciences, Hiratsuka, Japan. 相似文献
6.
A genetical study was made of three diploid varieties of Fragaria vesca, namely, wild type and two cultivated Alpine varieties, Baron Solemacher and Bush White. The varieties differ in several characters, including flowering habit, runnering habit, branching habit and fruit colour. Wild type is seasonal flowering, produces runners, has a simple branching habit and has red fruit. Both the Alpine varieties have a perpetual flowering (everbearing) habit and produce no runners. Buron Solemacher resembles wild type in branching habit and fruit colour, whereas Bush White has a very bushy habit (i.e., has a large number of crowns per plant) and has white fruit.Wild type F. vesca was crossed with the two Alpine varieties, and the F1 progenies were selfed and back-crossed to the Alpine parents. The results indicate that the differences in flowering habit are controlled by a single major gene, seasonal flowering being dominant to perpetual flowering, the recessive alleles in the two perpetual flowering varieties apparently being identical. Differences in runnering habit also appear to involve a single gene locus but non-runnering is associated with the bushy habit in Bush White and therefore either the three alleles of the same gene occur or the gene controlling bushiness in separate but closely linked with the gene controlling runnering. Fruit colour is controlled by one major gene locus, red being dominant to white fruit. All three major genes segregate independently. In all cases the characters of the wild type are dominant. The possible nature of the physiological process controlled by the gene for flowering habit is discussed. 相似文献
7.
Summary When Asiatic lilies are forced during the winter period, additional light is needed to prevent flower bud abscission and flower bud blasting. Growth room experiments showed considerable differences among eight lily cultivars in their response to low light. Among these cultivars, Connecticut King and Enchantment appeared to be the most sensitive to low light conditions while Uncle Sam and Scout were the least sensitive.Analysis of an incomplete diallel cross between nine cultivars showed significant differences in general combining ability (GCA) for flower bud abortion, number of buds, forcing time, plant height and leaf scorch under winter greenhouse conditions. Enchantment had the highest positive GCA for bud abortion, indicating a high sensitivity to low light conditions. Uncle Sam had the lowest GCA. Pirate and Scout appeared to have a high GCA for sensitivity to leaf scorch. Connecticut King was found to be a probable source of cytoplasmic male sterility. The data suggest that male sterility is associated with better response to low light conditions. 相似文献
8.
Limited but specific variations of seed storage proteins in Japanese common wheat (Triticum aestivum L.) 总被引：2，自引：0，他引：2
The electrophoretic banding patterns ofgliadin in common wheat lines derived fromJapan were determined byacid-polyacrylamide gel electrophoresis. For the 107 wheat lines used in our study,27 different patterns were identified, 13corresponding to the -gliadin, 8 tothe , -gliadin and 6 to the-gliadin. The gliadin patterns ofJapanese wheat cultivars and landracesgreatly differed from the patterns of wheatlines from other countries, and thevariation seen in wheat lines from Japanwas limited to 46 patterns. Sevencollection or breeding areas in Japanshowed different frequencies in theirgliadin patterns. Combining the gliadinpatterns with high molecular weightglutenin subunit compositions, 67combinations were observed. One gliadinpattern consisting of -gliadinpattern F, , -gliadinpattern H and -gliadin pattern Dwas frequently found in many Japanese wheatlines, though the other patterns werelimited to only one or two wheat lines. 相似文献
9.
J. C. Dorst 《Euphytica》1965,14(2):139-142
The author draws our attention to the book Production et fixation des variétés dans les végétaux published 100 years ago.This book gives us a clear picture of the knowledge and ideas prevailing in plant breeding at that time.
Production et fixation des variétés by Carrière, 1865相似文献
10.
J. G. Boonman 《Euphytica》1978,27(3):649-656
Summary Selections of four maturity classes developed from within each of three commercial varieties of Rhodes grass, Mbarara, Masaba and Pokot, were assessed for yield of PGS (pure germinating seed), speed of establishment after sowing, total dry matter yield and dry matter yield under frequent clipping (persistence), over three years.The range in heading date between the selections was well outside the range of the original varieties. The best selection with the highest overall response was the early-heading selection developed out of Mbarara with a 127% gain in PGS yield, 75% gain in dry matter yield three months after sowing, 11% gain in overall dry matter yield and 17% gain in dry matter yield under frequent clipping, compared with the standard Mbarara.Mbarara entries were the best in PGS yield, herbage yield and % dry matter. Masaba entries were better in persistence, while the late-heading Pokot entries were the poorest in PGS yield, herbage yield and persistence.Within varieties, yield of PGS dropped progressively and sharply in later maturity classes, whereas dry matter yields were largely unaffected by heading date. Thus late-heading selections dropped below the standard varieties in PGS yield but remained above the standard varieties in dry matter yield.Early-heading selections were generally more persistent than late-heading selections. 相似文献
11.
M. E. Aken'ova 《Euphytica》1982,31(1):161-165
Summary The occurrence of three male-sterile plants is reported. One in a population of ex-Bormu, an improved recommended variety of day-length neutral gero bulrush millet and the two others in the selfed progeny of a population of maiwa bulrush millet, a short-day photoperiod-sensitive type. Tests confirmed the cytoplasmic-genic nature of the male-sterility in the gero population. No tests could be conducted for maiwa.The transfer of male-sterility from the male-sterile Tift 23A bulrush millet, obtained from the United States, into a maiwa population is also reported. After six backcrosses the maiwa genotype appeared to have been reconstituted against the background of a male-sterility inducing cytoplasm. Maiwa male-sterility maintainer plants have also been identified. 相似文献
12.
Nonparametric measures of phenotypic stability. Part 1: Theory 总被引：4，自引：0，他引：4
Manfred Huehn 《Euphytica》1990,47(3):189-194
Summary For an estimation of phenotypic stability of genotypes grown in different environments three stability parameters have been proposed which are based upon the ranks of the genotypes in each environment: In a two-way table with K rows (genotypes) and N columns (environments) the original data xij (=phenotypic value of the i th genotype in the j th environment (i=1,2,...,K;j=1,2,...,N)) are transformed into ranks for each of the N environments separately. We denote: rij=rank of genotype i in environment j. Then, a genotype i may be considered to be stable over environments if its ranks are similar over environments (maximum stability = equal ranks over environments). Each statistic for the similarity of the ranks in each row = genotype may be used as a stability parameter. Three different measures are proposed and discussed.One of these nonparametric measures is defined as a ratio between variability of the rij's and mean of the rij's and, therefore, it represents a confounding and simultaneous consideration of stability and yield.Differences among genotypes have an effect on the stability measures and may lead to differences in stability among genotypes when in fact there is no genotype-environment interaction. To avoid this ambiguity one may correct the xij values for the genotypic effects and the nonparametric measures may be computed using the ranks based on the corrected values xij
*=xij–(\-xi.–\-x..)where \-xi.=marginal mean of genotype i and \-x\2=overall mean.Finally, approximate tests of significance based on the normal distribution are discussed for the two nonparametric measures mean absolute rank difference and variance of the ranks for 1) testing the stability of a certain genotype and 2) comparing the stabilities of different genotypes. 相似文献
13.
Summary No antagonistic or synergistic interaction was found between isolates of Uromyces appendiculatus var. appendiculatus and Xanthomonas campestris pv. phaseoli when inoculated to the same plant. A single dominant gene was suggested to control resistance to three isolates of rust in the crosses Pompadour Checa × Chichara and Pompadour Checa × NE W-4. A two-gene model was confirmed for the reaction to the three rust isolates for the crosses Pompadour Checa × GN Tara and Pompadour Checa × San Cristobal; a dominant (Ur
p) gene determined resistance and was epistastic to a dominant gene (Ur
t) for susceptibility. (Ur
t) was expressed only in the presence of recessive (ur
p) alleles. The reaction to common bacterial blight was quantitatively inherited and an association was detected with plant habit but not with rust reaction and leaf variegation. Plants with leaf variegation and crippled growth, were detected in the progeny of the cross Pompadour Checa × GN Tara and were controlled by duplicate recessive genes (mutatorunstable genes) and three genes, acting additively, respectively. The developmental expression of the latter trait varied considerably. Linkage was detected between genes controlling the variegated and the crippling traits.Published as Paper No. 7839, Journal Series, Nebraska Agricultural Experiment Station. Research was conducted under project No. 20-036. 相似文献
14.
Summary Deep water rice varieties in general have certain peculiar characters which are associated with floating habit. These characters are (i) early nodal differentiation, (ii) nodal rooting, (iii) spreading habit, (iv) awned grains, (v) brown hull colour, (vi) red pericarp (red rice), and (vii) seed dormancy. Inheritance of these characters and linkage relationship of genes governing these characters were studied in a cross between Pankaj (non floating) and Nageribao (floating) rice varieties. Nageribao, a cultivar from Assam possesses these characters.Early nodal differentiation was observed to be controlled by a single dominant gene, designated as Nd. Nodal rooting was controlled by two dominant complementary genes, designated as Nr
1 and Nr
2. We found an inhibitory factor for spreading habit and one for brown hull colour in Pankaj; the operation of two dominant duplicate genes An
1 and An
2 for controlling awning characters, a single dominant gene Rd for red pericarp colour and a single dominant gene Gd for grain dormancy. Joint segregations between these characters resulted in the assignment of genes in the X linkage group of indica rices with estimated map distances based on the cross-over values. The genes An (awning), Es (spreading habit), Nr (nodal rooting) and Nd (nodal differentiation) were observed to be associated with each other. The gene for red pericarp (Rd) was observed to be linked with the grain dormaney gene Gd. 相似文献
15.
J. W. van Ooijen 《Euphytica》1989,44(1-2):81-94
Summary Quantitative genetic theory for autogamous crops enables the estimation of the parameters m (F-mean) and D (F-variance) in the F3-generation. With these estimated m and D a prediction can be made of the probability of finding superior inbred lines in the F-offspring of the cross. The accuracy of this procedure is influenced by the correctness of the genetic model, by the magnitude of the error variance, and by the bias caused by intergenotypic competition, which is present in the environment in which the F3 is grown and absent in the monoculture environment at which the selection is aimed, especially in a cereal crop like wheat. The influence of the intergenotypic competition was investigated by a special method of simulating segregating populations. In this method genotypes in the offspring of a cross are represented by varieties and segregating populations are composed by mixing the appropriate varieties according to the proper segregation frequencies. Growing the simulated population enables the estimation of m and D in the normal selection environment, while simultaneously growing the varieties in a large monoculture trial enables the calculation of true values of m and D in the monoculture environment. Hence, a comparison is possible.The first of this set of two papers presents the investigations on the influence of intergenotypic competition on the estimation of the parameter m. The correlation coefficient of the estimates from the selection environment with the calculated true values from the monoculture environment was small. Sometimes the selection environment estimation significantly underestimated the (true) monoculture value of m, sometimes it significantly overestimated the monoculture value. On the average the smaller true values of m were underestimated and the larger ones overestimated. 相似文献
16.
In Corchorus sidoides
F. Muell x C. siliquosus L. , the pod set was 19.05 per cent. and the percentage of pod harvested (out of set pods) was 100 per cent.. All seeds of the cross pods were non-viable.In C. siliquosus L. x C. sidoides
F. Muell. , the pod set was 8.7 per cent. and the percentage of pod harvested was 100. In this case the seeds were also non-viable.The genus Corchorus comprises species which are systematically widely related. The possibility of getting viable hybrids in this case is impossible because the phylogenetic relationship does not allow of getting viable seeds. A karyotypic study of these species will throw light on this aspect and breeders will then get a tool for handling this subject.Department of Agriculture, Calcutta University 相似文献
17.
Summary A greenbug [Schizaphis graminum (Rondani)] resistant strain of rye (Secale cereale L.) Insave F.A. from Argentina was crossed with Chinese Spring wheat (Triticum aestivum L.) and also with Elbon and Balbo cultivars of common rye. Juvenile plants of the primary wheat X rye hybrid were treated with colchicine. Partially fertile amphidiploids were obtained that are resistant to greenbug Biotypes B and C. F1 and F2 populations of seedling plants derived from crosses of Insave F.A. with Elbon and Balbo rye were tested for reaction to the greenbug to determine the genetic basis of inheritance. The results confirmed previous reports that resistance in Insave F.A. is conditioned by a single dominant gene.Deceased 相似文献
18.
Ten snap beans (Barrier, Brio, Carson, Cornell 502, CT 70, HB 1880, Hystyle, Labrador, Opus and Venture) were selected for differential temperature tolerance and used as parents in a complete diallel mating design. The 45 F1 hybrid lines (with reciprocals) and parents were screened at 32 C day/28 C night, and in a separate experiment, 16 C day/10 C night, during reproductive development in replicated controlled environments. Variation for yield under temperature treatments was observed among parents and hybrids, with certain hybrids exceeding parental performance. Significant (P 0.0001) general combining ability (GCA), and significant (P 0.05) specific combining ability (SCA) were observed for yield components including pod number, seed number, and seeds per pod. There was evidence that pod number and seeds per pod under temperature stress are under separate genetic control. Reciprocal effects and heterosis were not significant. GCA could not be predicted from parental performance. The breeding line Cornell 502 had the highest GCA under high temperature, and the cultivar Brio had the highest GCA under low temperature. The cross Brio × Venture was high yielding in both temperature treatments. Heat tolerance and chilling tolerance were associated in certain parents and hybrids. However, performance under high and low temperature treatments was not generally correlated in the parents and hybrids, indicating that these traits should be selected separately. 相似文献
19.
Summary F1 hybrids between short-day photoperiod- sensitive maiwa bulrush millet, Pennisetum americanum (2n=14), and elephant grass, P. purpureum (2n=28), are triploid (2n=21), sterile, and can only be propagated vegetatively. Fertile amphidiploids, (2n=42, with 21 bivalents) were produced by colchicine treatment. Good seed set was obtained upon selfing the amphidiploids and the progeny exhibited variable pollen fertility and bivalent univalent and multivalent formation.Reciprocal crosses between elephant grass and the colchicine-induced amphidiploid failed to produce seeds. The maiwa millet x amphidiploid cross resulted in poor seed set and the reciprocal failed. Maiwa x amphidiploid hybrids were pollen sterile with 2n=21, rather than the expected 2n=28, indicating chromosome elimination.Morphologically, the amphidiploids and maiwa x amphidiploid hybrids closely resembled elephant grass and the F1 hybrid. The amphidiploids showed no superiority over the F1 hybrid and elephant grass in either forage yield or quality but one maiwa x amphidiploid genotype surpassed a promising local elephant grass selection in forage dry matter yield and flowered for a relatively short period. 相似文献
20.
Summary Inheritance of raw cucumber fruit texture (Magness-Taylor Fruit Pressure Tester firmness) was investigated over a 4-year period from 1971–1974. Results from 2 separate but related experiments suggested that firmness was quantitatively inherited with sufficient additive effects to permit gain from selection. In a selection study within 4 F2 populations derived from crosses between firm (Chipper and Gy3) and soft (Mincu and Green F) fruit type cultivars, variation among and within F3 and F4 families was significant but overall family means were not significantly higher than the high parent in any of the 4 crosses. Narrow sense heritability estimates for fruit texture were 0.80 in the Mincu × Chipper population and 0.77 in the Green F × Chipper, Mincu × Gy3, and Gy3 × Green F crosses. In a separate experiment, generation means analysis was used to assess the mode of gene action in 2 crosses: Green F × Chipper, and Gy3 × Green F. Additive genetic effects accounted for 98.8% and 99.3% of the total genetic variation within each cross, respectively.Scientific Journal Series Paper No. 9794. 相似文献