Chromosome-associated control of meiotic pairing differentiation. Variation within Secale cereale

Chromosoma ◽  
1972 ◽  
Vol 39 (4) ◽  
pp. 351-360 ◽  
Author(s):  
J. Sybenga
1984 ◽  
Vol 26 (4) ◽  
pp. 409-414 ◽  
Author(s):  
M. C. Cermeño ◽  
J. Orellana ◽  
J. R. Lacadena

The loss of bound chromosome arms through early, middle, and late metaphase I has been analyzed in a plant of inbred rye (Secale cereale L.) heterozygous for a terminal heterochromatic C-band of the long arm of chromosome 1R. From the increase in the number of univalent pairs due to bound arm loss, and from the comparison between the frequencies of bound arms at metaphase I and recombinant chromosomes at anaphase I, it is concluded that some of the chromosome bonds appearing at metaphase I are actually nonchiasmate associations that can be considered as remnants of prophase pairing. Conclusions concerning recombination obtained solely from the analysis of chiasma frequency measured as bound arms may be invalid.Key words: inbred rye, C-heterochromatin, meiotic pairing, nonchiasmate bonds.


Genetics ◽  
1985 ◽  
Vol 111 (4) ◽  
pp. 933-944
Author(s):  
J Orellana ◽  
J L Santos

ABSTRACT Meiotic pairing preferences between identical and homologous but not identical chromosomes were analyzed in ten induced tetraploid/diploid chimaeral rye plants (Secale cereale) heterozygous for telomeric heerochromatin C-bands in both arms of chromosome 1R. These plants were the progeny of two crosses between only one plant of cv. Petkus, used as male, and two plants of the inbred lines E and R, respectively. Different pairing preferences for chromosome 1R were found: (1) between plants, (2) between chromosome arms within the same plant and (3) between bivalents and multivalents within the same plant. The possible influence in the preferences of several factors such as differences in C-heterochromatin content in the chromosomes analyzed, specific genetic control and independence in pairing behavior between both arms and partner exchange is discussed.


Genetics ◽  
1983 ◽  
Vol 104 (4) ◽  
pp. 677-684
Author(s):  
J L Santos ◽  
J Orellana ◽  
R Giraldez

ABSTRACT Meiotic pairing preferences between identical and homologous but not identical chromosomes were analyzed in spontaneous tetraploid/diploid chimeras of three male grasshoppers (Eyprepocnemis plorans) whose chromosome pair 11 were heterozygous for C-banding pattern and in four induced tetraploid/diploid chimaeral rye plants (Secale cereale) heterozygous for telomeric heterochromatin C-bands in chromosomes 1R and 2R. In the grasshoppers, a preference for identical over homologous pairing was observed, whereas in rye both a preference for homologous rather than identical pairing and random pairing between the four chromosomes of the set was found. From the results in rye, it can be deduced that pairing preferences do not depend exclusively on the similarities between chromosomes involved. It is suggested that genotypic or cryptic structural differences between the homologous chromosomes of each pair analyzed might be responsible for the pairing preferences found. This hypothesis can also explain the results obtained in grasshoppers, although the possibility of premeiotic association cannot be excluded in this material.


1971 ◽  
Vol 18 (3) ◽  
pp. 311-328 ◽  
Author(s):  
A. M. Wall ◽  
Ralph Riley ◽  
Victor Chapman

SUMMARYPlants of Triticum aestivum (2n = 6x = 42) ditelocentric 5BL were treated with EMS in order to produce mutations in the 5B system by which meiotic pairing between homoeologous chromosomes is normally prevented. To check for the occurrence of mutation T. aestivum ditelo-5BL plants were pollinated with rye (Secale cereale 2n = 14) and meiosis was examined in the resulting hybrids.Wheat-rye hybrids were scored for the presence of mutants when the wheat parents were either the EMS-treated wheat plants, or their selfed derivatives, or their progenies obtained after pollination with untreated euploid individuals.Mutants were detected by each of these procedures and mutant gametes were produced by the treated ditelocentric plants with frequencies between 1·5 and 2·5%, but there were differences between the mutants in the extent to which homoeologous pairing occurred in the derived wheat-rye hybrids. The differences may have resulted from the occurrence of mutation at different loci or to different extents at the same locus.Two mutants, Mutant 10/13 and Mutant 61, were fixed in the homozygous condition. Mutant 10/13 was made homozygous both in the 5BL ditelocentric and in the euploid conditions but these genotypes regularly formed 21 bivalents at meiosis, and there was no indication of homoeologous pairing although the mutant 10/13 gave rise to homoeologous pairing in wheat-rye hybrids.


2015 ◽  
Vol 147 (4) ◽  
pp. 268-273 ◽  
Author(s):  
Yarui Su ◽  
Dale Zhang ◽  
Yuge Li ◽  
Suoping Li

Intergeneric hybrids and amphidiploid hybrids from crosses of Aegilopstauschii and Secale cereale were produced using young embryo rescue. The hybrids showed complete sets of both parental chromosomes. The dihaploid plants showed an average meiotic pairing configuration of 10.84 I + 1.57 II + 0.01 III. Genomic in situ staining revealed 3 types of bivalent associations, i.e. D-D, R-R and D-R at frequencies of 8.6, 8.2 and 83.3%, respectively. Trivalents consisted of D-R-D or R-D-R associations. These results suggested that both intra- and intergenomic chromosome homology were contributed to chromosome pairing. Derived amphidiploids with 2n = 28 paired at metaphase I of meiosis as 4.51 I + 11.70 II + 0.03 III. Chromosome pairing of amphidiploids appeared more or less regular, i.e. bivalent-like with some trivalent configurations.


Genome ◽  
1988 ◽  
Vol 30 (5) ◽  
pp. 793-796 ◽  
Author(s):  
M. C. Cuadrado ◽  
C. Romero

The present study analyzed meiotic pairing in wheat – rye hybrids obtained by crossing of Triticum aestivum cv. Chinese Spring with allogamous ryes, two cultivars of Secale cereale ('Don Enrique' and 'Selectión') and Secale cereale ssp. segetale. The results indicate that each rye type has different behaviour on hybrid meiotic pairing because they contain distinct genetic systems affecting meiotic pairing. In the case of 'Don Enrique' and 'Selección,' a polygenic system could be present, but not identical in both cultivars. On the other hand, Secale cereale ssp. segetale contained genes that strongly affect the genetic system controlling homoeologous pairing in wheat.Key words: homoeologous pairing, wheat – rye hybrids, polygenic system, major genes.


Genome ◽  
1991 ◽  
Vol 34 (1) ◽  
pp. 72-75 ◽  
Author(s):  
C. Cuadrado ◽  
C. Romero ◽  
J. R. Lacadena

Wheat–rye hybrids were analyzed to study how the homoeologous-pairing control of wheat is altered when specific regulators of groups 3 and 5 are lacking or mutated. Lack of the 3DS chromosome arm and the ph2b mutation showed the most significant effect, due to a deficiency or inactivity of the Ph2 suppressor. The 3DL, 5AS, and 5BS chromosome arms have a promoting effect, 5BS being the most effective. A weak suppressive effect of 3AS and 3AL is proposed, and a promotive effect of 5DS was not ruled out. The suppressive effect of 3BS is discussed.Key words: Triticum aestivum, Secale cereale, homoeologous chromosomes, genetic pairing regulation.


2018 ◽  
Vol 16 (S1) ◽  
pp. S273-S283
Author(s):  
Z. Mami-Soualem ◽  
N. Brixi ◽  
C. Beghdad ◽  
M. Belarbi

Le changement des habitudes alimentaires au cours de ces dernières années a abouti à l’apparition des maladies dites de civilisation, parmi elles le diabète sucré. Des approches diétothérapeutiques privilégient la consommation des produits céréaliers sous la forme la plus complète possible. Ce travail a pour but de tester l’efficacité des régimes expérimentaux préparés à base des grains complets des deux céréales, le sorgho (Sorghum bicolor L.) et le seigle (Secale cereale L.), sur la correction de l’hyperglycémie et des marqueurs du stress oxydant associés au diabète chez le rat mâle Wistar. Les résultats montrent que les rats diabétiques, soumis au régime seigle pendant quatre semaines, présentent une diminution significative de la glycémie qui atteint les 53,95 % à la fin de l’expérimentation, ce qui fait que leur taux en glycémie se rapproche de celui des normoglycémiques. Le sorgho blanc présente, d’une part, une diminution significative de la peroxydation lipidique intracellulaire et, d’autre part, une augmentation de l’activité de la glutathion peroxydase, la glutathion réductase ainsi que la vitamine C. Ces approches méthodologiques peuvent, en améliorant la connaissance de l’importance des céréales (fibres alimentaires solubles et des polyphénols) dans l’évolution du diabète, aboutir à des recommandations et à une éducation nutritionnelle du diabétique.


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