Effect of a rye B chromosome and its segments on homoeologous pairing in hybrids between common wheat and Aegilops variabilis

Two lines of common wheat cv. Chinese Spring, carrying simultaneous mutations for the two major homoeologous pairing wheat suppressor genes Ph1 and Ph2 have been developed and their pairing behaviour compared with that of the ph1b mutant of the same cultivar. Besides carrying the ph1b mutation, the first double mutant line lacked the chromosome arm pair 3DS, containing Ph2, whereas the second had a euploid constitution and carried the ph1b allele on 3DS. Hybrids of Aegilops variabilis and Secale cereale with mono-5B (ph1b) and 3D/3DL plants have also been obtained, where the 3D versus 3DL presence marked the two pairing alternatives (ph1b only and ph1b + Ph2−, respectively). In the wheat × Ae. variabilis hybrids, an 8% increase in total chromosome pairing, almost entirely ascribable to an increment of multivalent associations, was observed in the 2n = 34 + t plants with respect to their 2n = 35 sibs. The number of bivalents showed no significant difference, but a tendency towards a decrease, which was significant for the rod types, was exhibited by the Ph2− plants. A weaker but similar effect was observed in wheat itself. The different mutants, in fact, showed a similar percentage of paired chromosomes but varied in their pairing pattern. A significant reduction in the number of bivalents, owing to a decrease of the rings, only partly compensated for by an increase of the rods, was observed in the double mutants. They also exhibited an increase in the multivalent fraction, which was significant for the most complex associations. In both common wheat and its hybrids with Ae. variabilis the addition of a ph2 mutation thus seems to reinforce the ph1b effect in promoting homoeologous pairing. On the other hand, such an effect was not noticed in the wheat × S. cereale hybrids. However, possible quantitative differences could have been masked by the considerable plant-to-plant variation and potential differences in relative incidence of wheat–wheat versus wheat–rye associations were undetectable in the Feulgen-stained materials analyzed.Key words: common wheat, interspecific hybrids, homoeologous pairing, Ph mutations.

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Effect of different doses of group-2 chromosomes on homoeologous pairing in intergeneric wheat hybrids

Canadian Journal of Genetics and Cytology ◽

10.1139/g86-033 ◽

1986 ◽

Vol 28 (2) ◽

pp. 240-246 ◽

Cited By ~ 11

Author(s):

C. Ceoloni ◽

I. Strauss ◽

M. Feldman

Keyword(s):

Common Wheat ◽

Chinese Spring ◽

Intergeneric Hybrid ◽

Homoeologous Pairing ◽

Aegilops Variabilis ◽

Group 2 ◽

Wheat Hybrids ◽

A Minor ◽

Homoeologous Chromosomes ◽

Different Doses

While an extra dose of chromosome 2A of common wheat, previously reported to carry a pairing promoter on its short arm, did not increase pairing between homoeologous chromosomes in F1 hybrids between common wheat cv. Chinese Spring (CS) and Aegilops variabilis, two doses of chromosome 2D or 2B caused a significant increase in homoeologous pairing. Evidently, chromosomes 2D and 2B carry a pairing promoter(s). Studies of F1 hybrids between aneuploids of CS, either deficient for chromosome 2D or having it in an extra dose, and Ae. variabilis, Ae. longissima, and Secale cereale supported the finding that this chromosome carries a pairing promoter. Using ditelosomic lines, the promoter was found to be located on the short arm of 2D (2DS). It was deduced that the promoter of 2B is also located on the homoeologous short arm, i.e., on 2BS. Evidence was obtained that the long arm of 2D may carry a suppressor(s) of pairing. Thus, the short arm of 2A, 2D, and 2B carries a pairing promoter(s), while the long arm of 2D and possibly of 2A and 2B carry a minor suppressor(s). The promoters are more potent than the suppressors and the overall effect of group-2 chromosomes is pairing promotion.Key words: wheat, homoeologous pairing, pairing promoter, pairing suppressor, intergeneric hybrid, meiosis.

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Effect of Ph2 mutants promoting homoeologous pairing on spindle sensitivity to colchicine in common wheat

Genome ◽

10.1139/g87-110 ◽

1987 ◽

Vol 29 (4) ◽

pp. 658-663

Author(s):

Carla Ceoloni ◽

Moshe Feldman

Keyword(s):

Common Wheat ◽

Suppressor Gene ◽

Intergeneric Hybrids ◽

Differential Sensitivity ◽

Root Tip ◽

Lower Sensitivity ◽

Homoeologous Pairing ◽

Wild Type ◽

Cellular Target ◽

Chromosome Arm

Two lines of common wheat cv. Chinese Spring carrying mutant alleles for the Ph2 homoeologous pairing-suppressor gene on chromosome arm 3DS promoting homoeologous pairing in wheat interspecific and intergeneric hybrids have been tested for their mitotic sensitivity to colchicine. Both the ph2a mutation, which corresponds to a fairly long deletion of 3DS, and ph2b, which is either an intragenic change or a very small deletion, as well as the ph2a/ph2b heteroallelic combination and the deficiency for the entire 3DS arm (ditelo 3DL), conditioned a significantly lower sensitivity to colchicine than that determined by the wild-type allele Ph2 (euploid and ditelo 3DS). Observation of both metaphase and anaphse root-tip cell populations, treated with various colchicine concentrations, provided similar results. The degree of spindle disruption in 2 × 10−4 M colchicine, as measured by the percentage of fully affected metaphases (C type), was significantly reduced in ph2 and Ph2− genotypes and, consequently, a larger proportion of cells could proceed toward anaphase and also had a regular segregation pattern at this stage. The differential sensitivity of ph2 genotypes to colchicine is in the opposite direction to that previously found for ph1 genotypes, lacking the homoeologous pairing suppressor on chromosome arm 5BL. The ph2 mutation, while promoting homoeologous pairing as ph1 does, decreases spindle sensitivity to colchicine with respect to the wild-type (ph2) allele rather than increasing it, as ph1 does. The observed alteration of spindle sensitivity to colchicine that mutants for structurally unrelated but functionally related genes (Ph1 and Ph2) condition is interpreted as a highly probable coincidence in their cellular target. It is assumed therefore that these loci affect the equilibrium between tubulin and microtubules. Through this effect they presumably determine chromosome positioning in somatic and premeiotic stages, leading to different pairing patterns at meiosis. Key words: Triticum aestivum, tubulin, pairing suppressors, somatic association.

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Promotion of homoeologous chromosome pairing in hybrids of Triticum aestivum × Aegilops variabilis

Genome ◽

10.1139/g90-124 ◽

1990 ◽

Vol 33 (6) ◽

pp. 825-828 ◽

Cited By ~ 13

Author(s):

S. Farooq ◽

N. Iqbal ◽

T. M. Shah

Keyword(s):

Triticum Aestivum ◽

Chromosome Pairing ◽

Chinese Spring ◽

Chiasma Frequency ◽

Intergeneric Hybrids ◽

Mutant Form ◽

Homoeologous Pairing ◽

Homoeologous Chromosome ◽

Homoeologous Chromosome Pairing ◽

Aegilops Variabilis

Intergeneric hybrids of Triticum aestivum variety Lu-26 and ph1b mutant of the cultivar Chinese Spring were produced with three accessions, A, B, and E, of Aegilops variabilis. Significant differences were found in the amount of homoeologous chromosome pairing at meiotic metaphase I. Hybrids between wheat variety Lu-26 and accessions A and B of Ae. variabilis showed very little pairing, as indicated by the chiasma frequency of 1.0 and 1.5 per cell, respectively. Hybrids between Lu-26 and accession E, on the other hand, showed significantly increased homoeologous pairing (mean chiasma frequency, 12.6/cell). The level of such pairing was essentially the same as that between the hybrids of ph1b 'Chinese Spring' × Ae. variabilis accessions A and B. However, when the ph1b mutant was hyridized with accession E, the level of chromosome pairing increased significantly (mean chiasma frequency, 17.52/cell). This is indicative of the presence of pairing promoter gene(s) in Ae. variabilis accession E, which are epistatic to the wheat Ph1 allele and positively interact with its mutant form to further increase the ph1b ceiling to homoeologous pairing in wheat.Key words: Triticum aestivum, ph1b mutant, Aegilops variabilis, intergeneric hybrids, homoeologous pairing.

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Comparative analysis of the homoeologous pairing effects ofphKLgene in common wheat ×Psathyrostachys huashanicaKeng ex Kuo

Cereal Research Communications ◽

10.1556/crc.36.2008.3.7 ◽

2008 ◽

Vol 36 (3) ◽

pp. 429-440 ◽

Cited By ~ 7

Author(s):

H. Kang ◽

H. Zhang ◽

Y. Wang ◽

Y. Jiang ◽

H. Yuan ◽

...

Keyword(s):

Comparative Analysis ◽

Common Wheat ◽

Homoeologous Pairing

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Transfer of Ph I genes promoting homoeologous pairing from Triticum speltoides to common wheat

Theoretical and Applied Genetics ◽

10.1007/bf00222400 ◽

1994 ◽

Vol 88 (1) ◽

pp. 97-101 ◽

Cited By ~ 80

Author(s):

P. D. Chen ◽

H. Tsujimoto ◽

B. S. Gill

Keyword(s):

Common Wheat ◽

Homoeologous Pairing

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GENETICS SOCIETY OF CANADA AWARD OF EXCELLENCE LECTURE AN INDUCED MUTANT WITH HOMOEOLOGOUS PAIRING IN COMMON WHEAT

Canadian Journal of Genetics and Cytology ◽

10.1139/g77-063 ◽

1977 ◽

Vol 19 (4) ◽

pp. 585-593 ◽

Cited By ~ 263

Author(s):

E. R. Sears

Keyword(s):

Common Wheat ◽

Intermediate Level ◽

Homoeologous Pairing ◽

Male Sterile ◽

Normal Pollen ◽

Chromosome 5B ◽

Homozygous Mutant ◽

Induced Mutant

An apparent deletion of Ph, the chromosome-5B suppressor of homoeologous pairing, was obtained by X-raying normal pollen and using it on plants monosomic for a 5B chromosome carrying the marker Hairy-Neck, previously transferred from rye. Of the 1278 M1 offspring, 675 were eliminated without test, because they were either 1) hairy necked and therefore possessing a maternal 5B that would have hidden any deficiencies present in the X-rayed 5B; 2) nullisomic in appearance and thus likely to have a badly damaged 5B; or 3) completely or nearly male sterile, which precluded the recovery homozygous of any mutant that might have been present. A total of 438 M1 plants were tested for pairing mutations, mostly by crossing to Triticum kotschyi and looking for increased pairing. Only one mutation was obtained that appears to be a deficiency of Ph. The homozygous mutant is somewhat reduced in vigor and fertility, and male transmission from the heterozygote was only 38.6%. A second mutation, which leads to an intermediate level of homoeologous pairing, is not located on chromosome 5B.

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Arm homoeology of wheat and rye chromosomes

Genome ◽

10.1139/g87-149 ◽

1987 ◽

Vol 29 (6) ◽

pp. 873-882 ◽

Cited By ~ 180

Author(s):

T. Naranjo ◽

A. Roca ◽

P. G. Goicoechea ◽

R. Giraldez

Keyword(s):

Key Words ◽

Common Wheat ◽

Chinese Spring ◽

Structural Changes ◽

Meiotic Pairing ◽

Homoeologous Pairing ◽

Wheat Evolution ◽

C Banding ◽

Chromosome Arm ◽

Homoeology Relationships

Meiotic pairing was studied at metaphase I in three different cv. Chinese Spring × rye hybrid combinations (5B deficient, 3D deficient, and normal ABDR) to establish the arm homoeology of wheat and rye chromosomes. The majority of individual wheat chromosomes and their arms, as well as the arms of chromosomes 1R and 5R, were identified by means of C-banding. The results on pairing relationships support the genome reallocation of chromosomes 4A and 4B. The short arms of wheat chromosomes belonging to homoeologous groups 1, 3, 5, and 6 and of chromosome pairs 4A–4D and 7A–7D showed full pairing homoeology as well as the long arms of wheat chromosomes of groups 1, 3, 6, and 7 and of chromosome pairs 4A–4D and 5B–5D. Chromosomes 2A, 2B, and 2D were homoeologous, but the homoeologies of their arms were not identified. Reduced homoeologies of the 4BL arm to 7AS and 7DS, of the 5AL arm to 4AL and 4DL, and of the 7BS arm to 5BL and 5DL were identified. Arms 4BL, 5AL, and 7BS are involved in a double translocation that arose during the evolution of common wheat. The homoeology relationships of chromosome arm 4BS were not identified since this arm seldom paired. The homoeologous pairing pattern between wheat chromosomes was characterized by a remarkable predominance of A–D associations, altered only by structural changes in groups 4 and 5. Chromosome arm 1RL showed full pairing homoeology to 1AL, 1BL, and 1DL, while 5RL was homoeologous to 5AL and partially homoeologous to 4AL and 4DL. It is concluded that 5RL carries a translocated segment from 4RL. Key words: homoeologous pairing, translocations, wheat evolution, C-banding.

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Effect of Protein Content on the Quantity and Size Distribution of Polymeric Protein in Common Wheat

Japanese Journal of Crop Science ◽

10.1626/jcs.80.77 ◽

2011 ◽

Vol 80 (1) ◽

pp. 77-83 ◽

Cited By ~ 1

Author(s):

Mikiko Yanaka ◽

Kanenori Takata ◽

Tatsuya M. Ikeda ◽

Naoyuki Ishikawa

Keyword(s):

Protein Content ◽

Size Distribution ◽

Common Wheat

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Effect of algae Ecklonia maxima extract (Kelpak SL) on yields of common wheat, durum wheat and spelt wheat

Agronomy Science ◽

10.24326/2019.1.1 ◽

2019 ◽

Vol 74 (1) ◽

pp. 5-14

Author(s):

GRZEGORZ SZUMIŁO ◽

LESZEK RACHOŃ ◽

BARBARA KROCHMAL-MARCZAK

Keyword(s):

Triticum Aestivum ◽

Durum Wheat ◽

Common Wheat ◽

Yield Components ◽

Grain Quality ◽

Foliar Application ◽

Control Treatment ◽

Favourable Effect ◽

Ecklonia Maxima ◽

Spelt Wheat

The 3-year experiment was concerned with the response of spring forms of common wheat (Triticum aestivum L. subsp. aestivum), durum wheat (Triticum durum Desf.) and spelt wheat (Triticum aestivum subsp. spelta L. em. Thell.) to the foliar application of a plant growth stimulant (extract from marine algae Ecklonia maxima), with the commercial name of Kelpak SL (GS), as compared to control treatment (C). The following parameters were analysed: yield of grain, yield components (number of ears, weight of 1000 kernels, number and weight of kernels per ear) and physical indicators of grain quality (test weight, uniformity and vitreosity of grain). The study showed that the level of yielding and the yield components were related primarily with the wheat genotype, but they depended also on the agro-climatic conditions and on the algae extract and control experimental treatments. The application of algae extract, compared to the control, caused a significant increase in the yields of the spring wheat species under study, on average by 7.0%. Canopy spraying with algae extract had a favourable effect on the number of ears, on he number and weight of kernels per ear, but it had no effect on the weight of 1000 kernels. The grain quality of durum wheat, spelt wheat and common wheat was affected more strongly by the weather conditions in the successive years of the study and by the genotype than by the foliar application of algae extract. The spelt genotypes were characterised by lower yields and lower grain quality than common wheat and the durum wheat genotypes.

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