Cytology of the TetraploidAllium RubellumBieb.
作者:
期刊:
Caryologia
(Taylor Available online 1971)
卷期:
Volume 24,
issue 2
页码: 149-155
ISSN:0008-7114
年代: 1971
DOI:10.1080/00087114.1971.10796422
出版商: Taylor & Francis
数据来源: Taylor
摘要:
Allium rubellumBieb. so far known as a diploid and a triploid has been collected in the tetraploid form (2n=4x=32) from the saffron fields and mud built house tops of Kashmir valley. Tetraploidy has caused gigantism in the size of the plant and the flower head. Root tip cells bear 32 chromosomes with median or submedian centromeres. Eight of the chromosomes are secondarily constricted. These do not match into pairs. Meiosis is characterized by a high frequency of quadrivalents ranging in number from 8 (maximum number possible) to 2 per cell. Anaphase distribution is regular in almost half of the microspore mother cells and only slightly irregular (17:15) in the rest. The subsequent course of meiosis is perfectly normal and as a consequence healthy pollen grains are produced. Though the high quadrivalent frequency points to autopolyploidy, in view of the karyotypic heteromorphicity the taxon seems to have arisen through hybridization at the varietal level.
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