B-chromosomen inCrepis capillaris

Barthelmess, Alfred; Bauchinger, M.

doi:10.1007/bf01725759

Cited by 3 publications

(2 citation statements)

References 1 publication

Supporting

Mentioning

Contrasting

Order By: Relevance

“…They have been reported from Germany (Barthelmiss & Bauchinger, 1962), Switzerland (Rutishauser, 1960), France and Britain (Parker et at., 1989;this paper). Crepis capillaris has also spread widely around the world as an adventive, and Bs have also been dispersed: Bs occur in plants collected in north India (Kaushal & Mehra, 1976).…”

Section: Discussionmentioning

confidence: 89%

The population cytogenetics of Crepis capillaris IV. The distribution of B-chromosomes in British populations

et al. 1991

View full text Add to dashboard Cite

Worcester, B-chromosomes reached maximum frequencies at mid-altitudes in large populations, declining both towards the summit and in the small, isolated lowland populations. It is suggested that Bs in Crepis are excluded from populations growing under sub-optimal conditions. B-frequency in a population at East Wretham Heath, Norfolk, remained constant over three generations despite a very strong accumulation mechanism operating in C. capillaris. Selection must operate against individuals with one or more B-chromosomes to maintain this constancy.

show abstract

Section: Discussionmentioning

confidence: 89%

The population cytogenetics of Crepis capillaris IV. The distribution of B-chromosomes in British populations

et al. 1991

View full text Add to dashboard Cite

show abstract

“…B-chromosomes have been reported from several localities in the widespread plant species Crepis capillaris (Abraham et a!., 1968;Rutishauser, 1960Rutishauser, , 1963Barthelmess and Bauchinger, 1962) and the stability and inheritance of these Bs has been described in plants derived from a Swiss population (Rutishauser, 1963;Rutishauser and Rothlisberger, 1966;Rothlisberger, 1970). In the Swiss accession the Bs regularly undergo somatic non-disjunction in shoot meristems at the time of floral initiation with the result that the B-number in the flowers, and hence the germ-line, is increased.…”

Section: Introductionmentioning

confidence: 99%

The population cytogenetics of Crepis capillaris. II. The stability and inheritance of B-chromosomes

et al. 1989

View full text Add to dashboard Cite

Metacentric B-chromosomes in Crepis capillaris undergo somatic non-disjunction in the developing inflorescences. Nondisjunction occurs at several stages in development and is seen as differences in B-number (i) between pollen mother cells (PMCs) within florets, (ii) between florets within capitula, and (iii) between capitula within inflorescences. About half the plants studied showed variation in B-number within the inflorescence. The number of Bs in inflorescences is very variable but in most plants is greatly in excess of the zygotic number, ranging from 1.00 to 3.56 per PMC in lB plants. Two rounds of non-disjunction occasionally occur in the same cell lineage. The inheritance of Es is greatly enhanced over Mendelian expectation with average transmission of 0.90 through the pollen and 0.83 through the egg. The role of accumulation in the maintenance of the C. capillaris B-chromosome polymorphism is considered. Very strong selection pressures must operate against B-containing plants or gametes in natural populations.

show abstract

B-Chromosome Systems in Flowering Plants and Animal Species

Jones

1975

International Review of Cytology

176

View full text Add to dashboard Cite

B-chromosomen inCrepis capillaris

Cited by 3 publications

References 1 publication

The population cytogenetics of Crepis capillaris IV. The distribution of B-chromosomes in British populations

The population cytogenetics of Crepis capillaris IV. The distribution of B-chromosomes in British populations

The population cytogenetics of Crepis capillaris. II. The stability and inheritance of B-chromosomes

B-Chromosome Systems in Flowering Plants and Animal Species

Contact Info

Product

Resources

About