C-banding in meiosis: an approach to the study of wheat and rye genome interactions in triticale

Genome ◽  
1989 ◽  
Vol 32 (6) ◽  
pp. 1074-1078 ◽  
Author(s):  
C. Galindo ◽  
N. Jouve

Meiosis in four primary hexaploid triticale lines, in their component two tetraploid wheat and two rye parents, and in the hybrids obtained by crossing within each ploidic level was studied using Giemsa banding. The individual chromosomes were identified and their meiotic behaviour at first metaphase was analyzed in each line. In each new triticale line, the level of pairing for wheat chromosomes was moderately reduced and for rye chromosomes was very significantly reduced, in comparison with that of the wheat and rye parents used to synthesize it. The pairing intensity observed suggests the presence of a strong negative intergenomic interaction between the rye and wheat genomes in triticale, irrespective of whether the rye is in a homozygous or heterozygous genotypic condition. The homozygosity or heterozygosity in the wheat constituent does not appear to effect the behaviour of the rye chromosomes in triticale.Key words: triticale, meiosis, C-banding, heterosis.

Genome ◽  
1989 ◽  
Vol 32 (5) ◽  
pp. 735-742 ◽  
Author(s):  
Nicolas Jouve ◽  
Carmen Galindo ◽  
Montserrat Mesta ◽  
Fernando Diaz ◽  
Beatriz Albella ◽  
...  

The distribution and characterization of heterochromatin in a series of cultivars, parents, new amphiploids and progeny of hexaploid triticale were comparatively studied using C-banding and morphometric analysis. A high level of intervarietal polymorphism was detected for the banding pattern. The chromosome pairs 4A and 1R presented the most constant pattern of heterochromatin distribution among 31 triticale lines studied. A total of 126 bands have been catalogued, from which 28, 59, and 39 belong, respectively, to the A, B and R genomes. The ratio of polymorphic bands per genome was 23/28, 36/59, and 30/39. The chromosomes displayed heterochromatin modifications consistent in both presence–absence and relative length of their content per genome, when passed from the parents to the amphiploids. Variations in the heterochromatin were also observed among sister plants coming from crosses between wheat and triticale. The heterochromatin content showed gradual tendencies either to increase or decrease in each genome during successive self-cross generations after that cross. The existence of a systematic process of variation of heterochromatin content in triticale is assumed, and the nature of this phenomenon is discussed.Key words: triticale, tetraploid wheat, rye, C-banding, heterochromatin.


Genome ◽  
2006 ◽  
Vol 49 (12) ◽  
pp. 1545-1554 ◽  
Author(s):  
J. Li ◽  
D.L. Klindworth ◽  
F. Shireen ◽  
X. Cai ◽  
J. Hu ◽  
...  

The aneuploid stocks of durum wheat ( Triticum turgidum L. subsp. durum (Desf.) Husnot) and common wheat ( T. aestivum L.) have been developed mainly in ‘Langdon’ (LDN) and ‘Chinese Spring’ (CS) cultivars, respectively. The LDN-CS D-genome chromosome disomic substitution (LDN-DS) lines, where a pair of CS D-genome chromosomes substitute for a corresponding homoeologous A- or B-genome chromosome pair of LDN, have been widely used to determine the chromosomal locations of genes in tetraploid wheat. The LDN-DS lines were originally developed by crossing CS nulli-tetrasomics with LDN, followed by 6 backcrosses with LDN. They have subsequently been improved with 5 additional backcrosses with LDN. The objectives of this study were to characterize a set of the 14 most recent LDN-DS lines and to develop chromosome-specific markers, using the newly developed TRAP (target region amplification polymorphism)-marker technique. A total of 307 polymorphic DNA fragments were amplified from LDN and CS, and 302 of them were assigned to individual chromosomes. Most of the markers (95.5%) were present on a single chromosome as chromosome-specific markers, but 4.5% of the markers mapped to 2 or more chromosomes. The number of markers per chromosome varied, from a low of 10 (chromosomes 1A and 6D) to a high of 24 (chromosome 3A). There was an average of 16.6, 16.6, and 15.9 markers per chromosome assigned to the A-, B-, and D-genome chromosomes, respectively, suggesting that TRAP markers were detected at a nearly equal frequency on the 3 genomes. A comparison of the source of the expressed sequence tags (ESTs), used to derive the fixed primers, with the chromosomal location of markers revealed that 15.5% of the TRAP markers were located on the same chromosomes as the ESTs used to generate the fixed primers. A fixed primer designed from an EST mapped on a chromosome or a homoeologous group amplified at least 1 fragment specific to that chromosome or group, suggesting that the fixed primers might generate markers from target regions. TRAP-marker analysis verified the retention of at least 13 pairs of A- or B-genome chromosomes from LDN and 1 pair of D-genome chromosomes from CS in each of the LDN-DS lines. The chromosome-specific markers developed in this study provide an identity for each of the chromosomes, and they will facilitate molecular and genetic characterization of the individual chromosomes, including genetic mapping and gene identification.


Genome ◽  
1990 ◽  
Vol 33 (5) ◽  
pp. 686-689 ◽  
Author(s):  
Charles M. Papa ◽  
R. Morris ◽  
J. W. Schmidt

Two winter hexaploid triticale populations derived from the same cross were selected on the basis of grain appearance and agronomic performance. The five lines from 84LT402 showed more kernel shriveling than the four lines from 84LT401. The derived lines were analyzed for aneuploid frequencies, rye chromosome banding patterns, and meiotic stability to detect associations with kernel development. The aneuploid frequencies were 16% in 84LT401 and 18% in 84LT402. C-banding showed that both selection groups had all the rye chromosomes except 2R. The two groups had similar telomeric patterns but differed in the long-arm interstitial patterns of 4R and 5R. Compared with lines from 84LT402, those from 84LT401 had significantly fewer univalents and rod bivalents, and more paired arms at metaphase I; fewer laggards and bridges at anaphase I; and a higher frequency of normal tetrads. There were no significant differences among lines within each group for any meiotic character. Since there were no differences within or between groups in telomeric banding patterns, the differences in kernel shriveling and meiotic stability might be due to genotypic factors and (or) differences in the interstitial patterns of 4R and 5R. By selecting plump grains, lines with improved kernel characteristics along with improved meiotic stability are obtainable.Key words: triticale, meiotic stability, C-banding, Secale cereale, heterochromatin.


1985 ◽  
Vol 65 (3) ◽  
pp. 487-490 ◽  
Author(s):  
A. E. LIMIN ◽  
J. DVORAK ◽  
D. B. FOWLER

The excellent cold hardiness of rye (Secale cereale L.) makes it a potential source of genetic variability for the improvement of this character in related species. However, when rye is combined with common wheat (Triticum aestivum L.) to produce octaploid triticale (X Triticosecale Wittmack, ABDR genomes), the superior rye cold hardiness is not expressed. To determine if the D genome of hexaploid wheat might be responsible for this lack of expression, hexaploid triticales (ABR genomes) were produced and evaluated for cold hardiness. All hexaploid triticales had cold hardiness levels similar to their tetraploid wheat parents. Small gains in cold hardiness of less than 2 °C were found when very non-hardy wheats were used as parents. This similarity in expression of cold hardiness in both octaploid and hexaploid triticales indicates that the D genome of wheat is not solely, if at all, responsible for the suppression of rye cold hardiness genes. There appears to be either a suppressor(s) of the rye cold hardiness genes on the AB genomes of wheat, or the expression of diploid rye genes is reduced to a uniform level by polyploidy in triticale. The suppression, or lack of expression, of rye cold hardiness genes in a wheat background make it imperative that cold-hardy wheats be selected as parents for the production of hardy triticales.Key words: Triticale, Secale, winter wheat, cold hardiness, gene expression


1977 ◽  
Vol 19 (2) ◽  
pp. 231-249 ◽  
Author(s):  
J. B. Thomas ◽  
P. J. Kaltsikes

Beginning at 120 hours prior to first metaphase of meiosis (MI) a 0.03% aqueous solution of colchicine was injected into the boot of pentaploid (hexaploid triticale × tetraploid wheat) hybrids developing at 20 °C ± 1° under continuous illumination. Colchicine applied 40 h or less prior to MI had no effect on chromosome pairing, while its application 40 h or more prior to MI induced a steady decline, culminating in a 40% reduction in chromosome pairing at about 80 h from MI. Between 48 and 35 h before MI (late premeiotic interphase to early zygotene) meiocytes underwent a period of active nucleolar fusion. The time, therefore, at which the colchicine sensitive aspects of chromosome pairing were completed coincided with the completion of nucleolar fusion. From comparison with other findings it was concluded that there is a colchicine sensitive bouquet stage which appears in leptotene and early zygotene; this bouquet is responsible for active nucleolar fusion and final close association between homologous chromosomes.


1971 ◽  
Vol 13 (3) ◽  
pp. 621-624 ◽  
Author(s):  
J. B. Thomas ◽  
P. J. Kaltsikes

A durum wheat background was shown to suppress the meiotic pairing of chromosomes of Secale montanum Guss. with homoeologues of S. cereale L. in hexaploid triticale. This effect was attributed to the activity of the 5BL diploidising system, apparently active in tetraploid wheat. It was considered unlikely that the SBL system was important in conditioning the normal level of pairing failure found in disomic triticales.


2020 ◽  
Vol 160 (1) ◽  
pp. 47-56
Author(s):  
Aybeniz J. Aliyeva ◽  
András Farkas ◽  
Naib Kh. Aminov ◽  
Klaudia Kruppa ◽  
Márta Molnár-Láng ◽  
...  

The chromosomal constitution of 9 dwarf (D) and 8 semidwarf (SD) lines derived by crossing hexaploid Triticale line NA-75 (AABBRR, 2n = 6x = 42) with Triticumaestivum (AABBDD, 2n = 6x = 42) cv. Chinese Spring was investigated using molecular cytogenetic techniques: fluorescence in situ hybridization and genomic in situ hybridization. A wheat-rye translocation (T4DS.7RL), 8 substitution lines, and a ditelosomic addition line (7RSdt) were identified. In the substitution lines, 1, 2, or 4 pairs of wheat chromosomes, belonging to the A, B, or D genome, were replaced by rye chromosomes. Substitutions between chromosomes belonging to different wheat genomes [5B(5A), 1D(1B)] also occurred. The lines were genetically stable, each carrying 42 chromosomes, except the wheat-rye ditelosomic addition line, which carried 21 pairs of wheat chromosomes and 1 pair of rye telocentric chromosomes (7RS). The chromosome pairing behavior of the lines was studied during metaphase I of meiosis. The chromosome pairing level and the number of ring bivalents were different for each line. Besides rod bivalents, univalent and multivalent associations (tri- and quadrivalents) were also detected. The main goal of the experiment was to develop genetically stable wheat/Triticale recombinant lines carrying chromosomes/chromatin fragments originating from the R genome of Triticale line NA-75. Introgression of rye genes into hexaploid wheat can broaden its genetic diversity, and the newly developed lines can be used in wheat breeding programs.


1983 ◽  
Vol 61 (3) ◽  
pp. 825-829 ◽  
Author(s):  
M. J. Asíns ◽  
C. Benito ◽  
M. Pérez de la Vega

A comparative study on the electrophoretic patterns of embryo plus scutellum, endosperm, and internal and external coats of rye (Secale cereale L. and Secale vavilovii Grossh.), tetraploid wheat (Triticum turgidum L. durum), and hexaploid Triticale during kernel maturation has been carried out. Each kernel part of each species showed a characteristic pattern, and slow pattern changes from the beginning of the study (5 days after pollination) until kernels reached maturity (dry kernels) were observed. The triticale peroxidase patterns were very similar to tetraploid wheat patterns, and only few rye isozymes were clearly observed, probably due to overlapping with wheat isozymes. The possible influence of rye genome on the expression of wheat isozymes in triticale is also discussed.


1984 ◽  
Vol 71 (1) ◽  
pp. 111-120
Author(s):  
I. Schubert ◽  
R. Rieger ◽  
P. Dobel

Similarities and differences become evident from comparisons of centromeric and non-centromeric banding patterns in plant and animal chromosomes. Similar to C and G-banding in animals (at least most of the reptiles, birds and mammals), centromeric and nucleolus-organizing region bands as well as interstitially and/or terminally located non-centromeric bands may occur in plants, depending on the kind and strength of pretreatment procedures. The last group of bands may sometimes be subdivided into broad regularly occurring ‘marker’ bands and thinner bands of more variable appearance. Non-centromeric bands in plants often correspond to blocks of constitutive heterochromatin that are rich in simple sequence DNA and sometimes show polymorphism; they thus resemble C-bands. However, most of these bands contain late-replicating DNA. Also they are sometimes rich A X T base-pairs, closely adjacent to each other and positionally identical to Feulgen+ and Q+ bands, thus being comparable to mammalian G-bands. Although banding that is reverse to the non-centromeric bands after Giemsa staining is still uncertain in plants, reverse banding patterns can be obtained with Feulgen or with pairs of A X T versus G X C-specific fluorochromes. It is therefore concluded that not all of the plant Giemsa banding patterns correspond to C-banding of mammalian chromosomes. Before the degree of homology between different Giemsa banding patterns in plants and G and/or C-bands in mammals is finally elucidated, the use of the neutral term ‘Giemsa band’, specified by position (e.g. centromeric, proximal, interstitial, terminal), is suggested to avoid confusion.


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