Chromosome pairing in tetraploid hybrids between Lolium perenne and L. multiflorum

Lewis, E. J.

doi:10.1007/bf00263105

Cited by 27 publications

(28 citation statements)

References 27 publications

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“…In the presence of four B chromosomes the allotetraploid hybrid behaves as a diploid showing bivalents, a few univalents, but no multivalents at metaphase I, while only univalents are seen at metaphase I in the diploid hybrid carrying two B chromosomes. In the absence of B chromosomes multivalents are present at metaphase I in the allotetraploid and in the diploid the complement is at this stage almost exclusively present as bivalen~s (11,12,40,74).…”

Section: Loliummentioning

confidence: 99%

The effect of chromosome 5B on synapsis and chiasma formation in wheat, triticum aestivum cv. Chinese Spring

Holm

Wang

1988

Carlsberg Res. Commun.

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The present paper summarizes and discusses the results obtained from a series of ultrastructural investigations of the effect of chromosome 5B on chromosome pairing and synaptonemal complex formation in wheat, T. aestivum cv. Chinese Spring. The material comprises hexaploid wheat nullisomic for chromosome 5B, monosomic for 5B, euploid wheat, wheat where chromosomes 5B have been replaced by one, two or three copies of an isochromosome for the long arm of chromosome 5B; trihaploid wheat with and without 5B and hybrids between Chinese Spring wheat and diploid rye with chromosome 5B, without 5B or carrying an isochromosome for the long arm of 5B. It is shown that nullisomy for chromosome 5B in hexaploid wheat results in a two-to threefold increase in the number of lateral components in multiple associations already from the beginning of zygotene and in trihaploid wheat and wheat-rye hybrids in a two-to threefold increase in the number of pairing partner exchanges per lateral component involved in synapsis. Only nullisomy for chromosome 5B and triisosomy for the long arm of chromosome 5B permit crossing over between the homoeologous chromosomes of wheat. It is inferred that the product of the Ph locus on chromosome 5B affects both synapsis and crossing over. As these timewise separated processes are assumed both to be initiated by heteroduplex formation, this might provide the common link in the action of the Ph gene. The results obtained with the genotypes containing different dosage of the Ph gene disprove both the hypothesis that Ph influences a premeiotic chromosome rearrangement (t 3, 14, 15) and the hypothesis (18, 82) that Ph controls the timing of crossing over with respect to the process of correction of multiple pairing associations.

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Section: Loliummentioning

confidence: 99%

The effect of chromosome 5B on synapsis and chiasma formation in wheat, triticum aestivum cv. Chinese Spring

Holm

Wang

1988

Carlsberg Res. Commun.

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“…Ideally for this sort of study a direct comparison between the tetraploid hybrid and autotetraploids of both parent lines should be made, as Lewis (1980) has done for Lolium. In this case however the presence of interchanges, would have confounded the comparison.…”

Section: The Modelmentioning

confidence: 99%

Does preferential pairing occur in Secale cereale × S. montanum tetraploid hybrids?

Chapman

1984

Heredity

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“…There exist genotypic differences in the levels of preferential chromosome pairing in the tetraploid hybrids between perennial and italian ryegrasses (Lewis 1980). It has been reported that there is a higher level of bivalent pairing and lower level of quadrivalent pairing in allotetraploid hybrids between perennial and italian ryegrasses than in the parent autotetraploid perennial ryegrass (Lewis 1980). Ahloowalia (1977), however, has reported higher level of multivalent pairing but lower level of bivalent pairing in the tetraploid hybrids of the same species.…”

Section: Introductionmentioning

confidence: 99%

“…Such regular meiotic behaviour is not achieved in synthetic amphiploids because associations often occur between the corresponding homoeologous chromosomes. in amphiploids, the mode of inheritance can vary from no preferential pairing (tetrasomic) to 100% preferential pairing (disomic) (Breese & Thomas 1978;Lewis 1980;Breese et al 1981;Thomas & Humphreys 1991). There exist genotypic differences in the levels of preferential chromosome pairing in the tetraploid hybrids between perennial and italian ryegrasses (Lewis 1980).…”

Section: Introductionmentioning

confidence: 99%

“…in amphiploids, the mode of inheritance can vary from no preferential pairing (tetrasomic) to 100% preferential pairing (disomic) (Breese & Thomas 1978;Lewis 1980;Breese et al 1981;Thomas & Humphreys 1991). There exist genotypic differences in the levels of preferential chromosome pairing in the tetraploid hybrids between perennial and italian ryegrasses (Lewis 1980). It has been reported that there is a higher level of bivalent pairing and lower level of quadrivalent pairing in allotetraploid hybrids between perennial and italian ryegrasses than in the parent autotetraploid perennial ryegrass (Lewis 1980).…”

Section: Introductionmentioning

confidence: 99%

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Meiotic behaviour in reciprocal tetraploid hybrids between perennial and Italian ryegrasses

Deniz

Doğru

2008

New Zealand Journal of Agricultural Research

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Chromosome associations and chiasma frequencies at first metaphase (MI) were studied in allotetraploid reciprocal hybrids between perennial ryegrass (Lolium perenne, Lp) and Italian ryegrass (L. multiflorum, Lm), and parent autotetraploid perennial ryegrass. Preferential chromosome pairings were assessed in Lp x Lm and Lm x Lp hybrids. The reciprocal hybrids were found to have significantly higher frequencies of bivalent pairing and lower frequencies of quadrivalent pairing and chiasmata. The mean frequencies of total bivalents at MI were 6.820, 9.885 and 10.040 and total quadrivalent frequencies were 3.320, 1.775 and 1.760 in the autotetraploid parent and the Lp x Lm and Lm x Lp hybrids, respectively. The frequencies of chiasmata were 25.075, 23.455 and 23.315 in the parent and the Lp × Lm and Lm × Lp hybrids, respectively. The frequencies of preferential chromosome pairing in the Lp × Lm and Lm × Lp hybrids were 42.69 and 44.85%, respectively and the results indicate a significant degree of preferential bivalent association in the hybrids. An inverse relationship was found between the frequency of total bivalent and quadrivalent associations in the parent and the Lp x Lm and Lm x Lp hybrids. These reciprocal hybrids are potentially important breeding materials for developing new hybrid cultivars.

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Chromosome pairing in tetraploid hybrids between Lolium perenne and L. multiflorum

Cited by 27 publications

References 27 publications

The effect of chromosome 5B on synapsis and chiasma formation in wheat, triticum aestivum cv. Chinese Spring

The effect of chromosome 5B on synapsis and chiasma formation in wheat, triticum aestivum cv. Chinese Spring

Does preferential pairing occur in Secale cereale × S. montanum tetraploid hybrids?

Meiotic behaviour in reciprocal tetraploid hybrids between perennial and Italian ryegrasses

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