Rye Chromosome 1R Research Articles

The effect of rye genetic information on zinc, copper, manganese and iron concentration of wheat shoots in zinc deficient soil

Experiments were conducted to study the genetic variability of Zn, Fe, Mn and Cu concentration in the shoot of wheat and other cereals. Cultivars of rye showed higher Zn efficiency than the wheats. There was a considerable variability for the four elements between rye and wheat varieties. By utilisation of disomic wheat-rye addition lines it could be demonstrated that the rye chromosomes 2R and 7R may improve the Mn and Fe concentrations of wheat, chromosome 1R the Zn and 5R the Cu, respectively. Even in a particular 4B/5R wheat-rye translocation line the Zn, Fe and Mn concentrations were significantly modified from 5.8 to 6.7, 92 to 171 and 123 to 236 ug/g DW, respectively. Both wheat and rye positively respond to Zn supply in Zn concentration of shoots, although the effect in rye is less pronounced. The average increases in Zn concentration in wheat and rye reached 851 % and 689 %, respectively, and correlated with a subsequent decrease of Cu>Fe>Mn. Among the wheats there were remarkable differences in the uptake of Zn additionally applied. The English variety ‘Avalon’ showed the best Zn utilisation.

Detection of a 4DL chromosome segment translocated to rye chromosome 5R in an advanced hexaploid triticale line Bronco 90

Bronco 90 is an advanced line of hexaploid triticale and was reported to be a 2D(2R) chromosome substitution type. In F1 hybrids of this triticale with bread wheat, however, a meiotic configuration of 16 bivalents and 10 univalents was frequently observed indicating the presence of an additional D(R) chromosome substitution or D/R translocation. To determine the chromosome constitution of Bronco 90, C-banding and fluorescent in situ hybridization techniques were applied to somatic and meiotic metaphase chromosomes. These analyses revealed that in Bronco 90, the terminal 7% of the long arm of rye chromosome 5R is derived from the long arm of chromosome 4D. This translocated chromosome (5RS.5RL-4DL) and telosome 4DL formed metaphase I bonds at a frequency of 71%, demonstrating the significance of small terminal chromosome segments for pairing. This novel rye-wheat translocation is probably generated by homoeologous crossing-over because the distal region of 5RL is known to be homoeologous to that of 4DL. Possible association of this translocation with the absence of hairy peduncle character in Bronco 90 is discussed.

The influence of 5-azacytidine on the condensation of the short arm of rye chromosome 1R in

The influence of 5-azacytidine on the condensation of the short arm of rye chromosome 1R in

Detection of the Sec-1 locus of rye by a PCR-based method.

The structural genes for the omega-secalins of rye (Secale cereale) are located in the Sec-1 locus on the short arm of rye chromosome 1R. We applied PCR (polymerase chain reaction) to detect the Sec-1 locus in a wheat genomic background. A primer set we designed based on a published sequence of a omega-secalin gene amplified not only the omega-secalin sequence, but also a putative omega-gliadin sequence. We determined partial sequences of both PCR-amplified fragments and designed different primers for the specific amplification of the omega-secalin sequence. One of the new primer sets amplified DNA fragments only in rye and wheat lines carrying chromosome 1R or telosome 1RS; no amplification occurred in either euploid wheats or 1RS deletion lines. This PCR-based method would provide efficient screening for the Sec-1 locus in progeny of wheat lines carrying chromosome 1R.

The Sec -1 locus on the short arm of chromosome 1R of rye ( Secale cereale )

This paper describes a detailed sequence analysis of the omega-secalin gene array at the Sec-1 locus on the short arm of chromosome 1 of rye. The analysis shows that the genes are separated by 8 kb of spacer sequence and that the gene/spacer units are arranged in a head to tail fashion. The boundaries of the array are identified, and a fragment containing the majority of the genes in the array is separated by PFG analysis. The sequence data of one 9.2 kb gene unit have been determined, and because of the similarity of the gene units within the array these data provide a detailed sequence analysis of 140 kb of the Sec-1 locus. Fluorescence in situ hybridization, using lambda clones isolated for the structural analysis, identifies the position of the array on the rye chromosomes relative to the 5S rRNA genes.

TheSec-1 locus on the short arm of chromosome 1R of rye (Secale cereale)

TheSec-1 locus on the short arm of chromosome 1R of rye (Secale cereale)

Linkage between a major gene for powdery mildew resistance and an RFLP marker on chromosome 1R of rye

AbstractDNA samples from an F2 progeny which segregated for resistance to powdery mildew were bulked for resistant and susceptible individuals. In a segregant analysis, genomic rye probes which had been localized previously in a linkage map of rye were systematically screened for polymorphisms between these bulks. An RFLP marker located on linkage group 1RS was found to be tightly linked to a dominant mildew resistance gene. This is the first publication mapping a major gene for mildew resistance in rye.

A genetic map of rye chromosome 1R integrating RFLP and cytogenetic loci

A genetic map of rye, Secale cereale L., chromosome 1R covering 247 cM was constructed utilizing 27 RFLP and four C-band markers, including terminal C-bands. Genetic mapping of C-bands and the centromere, and in situ hybridization of three RFLP clones, allowed for the integration of the genetic and cytological maps. Eight contact points between the genetic and cytological maps revealed variation in the recombination distance to cytological distance ratio ranging between 0.25 and 1.95, a 7.8-fold difference. Recombination was found to be highest in the satellite region of 1RS and lowest in the most distal region of 1RL.

RFLP maps of rye chromosomes 6R and 7R including terminal C-bands

A F2 mapping population was created from a cross between 'UC-90' and E-line ryes (Secale cereale L.), two lines that showed polymorphism for eight C-band loci. Clones from rye, as well as other grasses, were used as probes. RFLP maps of rye chromosomes 6R and 7R were generated that include the 6RS and 6RL terminal C-bands and the 7RS terminal C-band. The 6R map spans 230 cM and includes 9 loci. The 7R map covers 225 cM and includes 21 loci. Segregation distortion was detected for several chromosomal regions. Heterochromatic C-bands did not appear to be responsible for the distortion.

RFLP mapping of the vernalization (Vrn1) and frost resistance (Fr1) genes on chromosome 5A of wheat

A population of single chromosome recombinant lines was developed from the cross between a frost-sensitive, vernalization-insensitive substitution line, 'Chinese Spring' (Triticum spelta 5A) and a frost-tolerant, vernalization-sensitive line, 'Chinese Spring' ('Cheyenne' 5A), and used to map the genes Vrn1 and Fr1 controlling vernalization requirement and frost tolerance, respectively, relative to RFLP markers located on this chromosome. The Vrn1 and Fr1 loci were located closely linked on the distal portion of the long arm of 5AL, but contrary to previous observations, recombination between them was found. Three RFLP markers, Xpsr426, Xcdo504 and Xwg644 were tightly linked to both. The location of Vrn1 suggests that it is homoeologous to other spring habit genes in related species, particularly the Sh2 locus on chromosome 7 (5H) of barley and the Sp1 locus on chromosome 5R of rye.

Genetic mapping in the 1R.1D wheat–rye translocated chromosomes

Translocation chromosomes 1R.1D5+10−1 and 1R.1D5+10−2 were produced to improve bread-making quality in triticale and to manipulate the dosage of the Glu-D1 gene in wheat. They involve transfers of segments of the long arm of chromosome 1D of bread wheat to the long arm of rye chromosome 1R. The translocated long arms of the chromosomes were mapped genetically in wheat and triticale using polymorphism for C-banding patterns, allelic variation of the Glu-D1 gene, and a telocentric chromosome 1RL. The total frequency and the general distribution of recombination in the translocated arms was similar to that in normal long arms of group-1 chromosomes in wheat, rye, and triticale, except that the distal rye segments of the translocations showed a 15- to 20-fold increase in recombination frequency compared with normal 1R. Despite major differences in the physical structure of the translocated arms, both appeared very similar genetically, suggesting that genetic mapping is a poor indicator of the physical structure of translocations. Genetic length of the 1DL segment in chromosome 1R.1D5+10−1 was 31 cM, making the chromosome unsuitable for Glu-D1 dosage manipulation in wheat. The potential of chromosome 1R.1D5+10−2 for wheat breeding needs further testing. However, both chromosomes behave normally in hexaploid triticale.

Physical mapping of 5S rDNA reveals a new locus on 3R and unexpected complexity in a rye translocation used in chromosome mapping.

Using fluorescence in situ hybridization (FISH) with probe pScT7, three different 5S rDNA loci were detected in the satellite of rye chromosome 1R (5SDna-R1) and in the short arms of chromosomes 3R (5SDna-R3) and 5R (5SDna-R2) respectively. All three loci showed polymorphism for the hybridization signal intensity. In order to determine the localization of these rye 5S rDNA multigene loci with higher precision within the corresponding chromosome arms, the probe pScT7 was physically mapped by FISH in relation to the following five translocations (Wageningen Tester Set): T850W (1RS/4RL), T248W (1RS/6RS), T273W (1RS/5RL), T305W (2RS/5RS) and T240W (3RS/5RL). Accurate physical maps of the translocation breakpoints had previously been made using electron microscope analysis of spread pachytene synaptonemal complexes of heterozygotes for the different translocations. The results indicate that locus 5SDna-R3 is located between the breakpoint of translocation T240W and the telomere, whereas locus 5SDna-R2 is located between the breakpoint of translocation T305W and the centromere, the hybridization of probe pScT7 on T305W translocated chromosomes demonstrating the complex nature of this translocation. On the other hand, the simultaneous detection of probes pScT7 and pTA71 (18S-5.8S-26S rDNA) with two different fluorochromes, indicated that the breakpoints of translocations T850W and T248W are located between loci Nor-R1 and 5SDna-R1.

Presence of various rye-specific repeated DNA sequences on the midget chromosome of rye

The chromosome 1R of rye, or the midget chromosome, is necessary for plump, viable seed development and fertility restoration in the alloplasmic line with rye cytoplasm and a hexaploid wheat nucleus. The midget chromosome of rye represents 1/15th of the physical length of the chromosome 1R of rye. C-banding analysis indicated that the centromeric and pericentric region (approximately 30% physical length) of the midget chromosome is heterochromatic and the distant 70% physical length is euchromatic. These data suggest that the midget chromosome may represent the pericentric region of the long arm of chromosome 1R. In contrast with earlier reports, our results indicate that an array of rye-specific repeated sequences (both dispersed and tandem) are present on the midget chromosome. Various rye-specific repeated DNA sequences that are present on the midget chromosome will be useful in constructing a long-range map and studying the genomic organization of the midget chromosome. It is unclear if any of these repeated DNA sequences are involved in the origin of the midget chromosome.

The influence of the rye genome on the accumulation of HSP18 and HSP70 transcripts in a wheat genetic background

The influence of the rye genome on the accumulation of HSP18 and HSP70 transcripts in a wheat genetic background was examined in the wheat/rye hybrid triticale (Triticum aestivum cv Chinese Spring x Secale cereale cv Imperial). To quantify the amount of transcript accumulation in wheat, rye, triticale, and in the disomic and the ditelosomic rye addition lines to wheat, we used two independant methods, namely (1) Northern dot-blot hybridizations and (2) an exami-nation of the in-vitro translation products. Both the HSP18 and HSP70 transcripts were expressed at similar levels in Chinese Spring wheat, Imperial rye, and triticale. The HSP18 and HSP70 transcript levels of the disomic and the ditelosomic addition lines to wheat were compared to the transcript levels in wheat. With the exception of 5R, increased levels of HSP18 and/or HSP70 transcripts were expressed in all six of the remaining disomic addition lines. A neutral or suppressed level of HSP18 and HSP70 transcripts accumulated in addition lines 5R, 5RL, 5RS and 6RL. Wheat/rye genomic interactions influenced the level of heat-shock gene transcript accumulation in triticale. Rye chromosome 5R, and in particular both arms of rye chromosome 5R (5RL and 5RS), had a strong suppressive influence on the accumulation of wheat HSP18 and HSP70 transcripts. The genes controlling rye HSP expression appeared to be widely distributed throughout the rye genome.

A map of rye chromosome 4R with cytological and isozyme markers

The progeny of two crosses between a structural heterozygote for a reciprocal translocation (4RL/5RL) and a homozygote for the standard chromosome arrangement and of four crosses between standard chromosome homozygotes were analysed in rye (Secale cereale L. cv 'Ailés') for the electrophoretic patterns of five different leaf and endosperm isozymes (LAP, PGM, NDH, ADH and EPER). The presence or absence of the quadrivalents at metaphase I (MI) was also tested. Loci Adh-1, Pgm-1 and Ndh-1 were located on chromosome arm 4RS, and locus Eper-1 on chromosome arm 4RL. Locus Lap-2 was located on the 4RS chromosome arm. The estimated distances among the different linked loci support the following gene order: Eper1¨ (breakpoint-centromere)¨Lap-2¨ ¨Adh-1 ¨Pgm-1¨Ndh-1. These results provide evidence for the chromosomal location of Lap-2 locus on chromosome arm 4RS in cv 'Ailés'. A high negative interference was detected between the zones delimited by centromere and Lap-2, and Lap-2 and Pgm-1 in plants with the 4RL/5RL translocation.

Detection of rye chromosome 2R using the polymerase chain reaction and sequence-specific DNA primers.

Sequences derived from a rye gamma secalin gene were used as primers in polymerase chain reactions using DNA obtained from a series of wheat and triticale genetic stocks. A 473-bp fragment, the predicted size based on the distance between the selected primers, was found only in rye, triticales, and wheat lines carrying rye chromosome 2RS. Use of triticale lines with various wheat chromosome substitutions confirmed the chromosomal origin of the rye-specific marker. The presence of the 473-bp PCR product was always associated with the production of 75K secalins in grain samples. Thus, the primer sequences, and the clone of origin (pSC503), were both derived from the SEC-2 locus of rye chromosome 2RS.

Structural changes of rye chromosome 1R induced by a gametocidal chromosome.

A certain chromosome of Aegilops triuncialis is known to cause chromosomal aberrations in common wheat. We studied how frequently the Ae. triuncialis chromosome induced chromosome mutations in chromosome 1R of rye which was substituted for chromosome 1B in a common wheat cultivar. Wheat-rye translocations and deletions in chromosome 1R were found in more than 10% of the plants examined, and most of them were stably transmitted in the subsequent generations. The possible use of this system for inducing wheat-alien translocations is discussed in relation to wheat breeding.

Structural changes of rye chromosome 1R induced by a gametocidal chromosome

Structural changes of rye chromosome 1R induced by a gametocidal chromosome

A cytogenetic map on the entire length of rye chromosome 1R, including one translocation breakpoint, three isozyme loci and four C-bands

A cytogenetic map of the whole 1 R chromosome of rye has been made, with distances between adjacent markers shorter than 50% recombination. Included in the map are isozyme loci Gpi-R1, Mdh-R1 and Pgd2, the telomere C-bands of the short arm (ts1) and the long arm (tl1), two interstitial C-bands in the short arm proximal to the nuclear organizing region (NOR) (is1) and in the middle of the long arm (il1), respectively, and translocation T273W (Wageningen tester set). By means of electron microscope analysis of spread pachytene synaptonemal complexes, the breakpoint of this translocation was physically mapped in the short arm of 1R, proximal to NOR, and in the long arm of 5R (contrary to previous assumptions). The data indicated the marker order: ts1 - Gpi-R1 - is1 - T273W/Mdh-R1 - il1 - Pgd2 - tl1. A comparison between genetic and physical maps revealed that recombination is mainly restricted to the distal regions of both arms. For the translocation T273W, in heterozygotes no recombinants were observed between the translocation breakpoint and its two adjacently located markers (is1 and Mdh-R1), but recombination was not reduced in the distal regions of the chromosome. The segregations of several other isozyme and C-band markers also analyzed in the investigation presented here were consistent with observations of earlier authors concerning chromosome asignment and linkage relationships.

RFLP mapping of genes affecting plant height and growth habit in rye

RFLP mapping of chromosome 5R in the F3 generation of a rye (Secale cereale L.) cross segregating for gibberellic acid (GA3)-insensitive dwarfness (Ct2/ct2) and spring growth habit (Sp1/sp1) identified RFLP loci close to each of these agronomically important genes. The level of RFLP in the segregating population was high, and thus allowed more than half of the RFLP loci to be mapped, despite partial homozygosity in the parental F2 plant. Eight further loci were mapped in an unrelated F2 rye population, and a further two were placed by inference from equivalent genetic maps of related wheat chromosomes, allowing a consensus map of rye chromosome 5R, consisting of 29 points and spanning 129 cM, to be constructed. The location of the ct2 dwarfing gene was shown to be separated from the segment of the primitive 4RL translocated to 5RL, and thus the gene is probably genetically unrelated to the major GA-insensitive Rht genes of wheat located on chromosome arms 4BS and 4DS. The map position of Sp1 is consistent both with those of wheat Vrn1 and Vrn3, present on chromosome arms 5AL and 5DL, respectively, and with barley Sh2 which is distally located on chromosome arm 7L (= 5HL).