Hostname: page-component-68945f75b7-jtc8j Total loading time: 0 Render date: 2024-09-04T16:50:16.622Z Has data issue: false hasContentIssue false
  • English
  • Français

Non-homologous meiotic pairing in the A and B genomes of Brassica: its breeding significance in the production of variable amphidiploids

Published online by Cambridge University Press:  14 April 2009

Shyam Prakash
Shyam Prakash
Affiliation:
Cummings Laboratory, Indian Agricultural Research Institute, New Delhi-India

Summary

Core share and HTML view are not available for this content. However, as you have access to this content, a full PDF is available via the ‘Save PDF’ action button.

Brassica juncea Coss (2n = 36) is a naturally occurring allotetraploid. In the progenies of F1 hybrids of its constituent parents B. campestris sub.sp. oleifera var. toria × B. nigra and B. campestris sub.sp. japonica × B. nigra, the majority of the plants were parthenogenetic homozygous amphidiploids like B. juncea whereas a few differed in morphological and physiological characteristics. The latter, presumed to have arisen partheno-genetically, were suspected to be homozygous for chromosomes changed by allosyndetic recombination. One of these derived plants with curley leaves was crossed first with one of the homozygous amphidiploids and secondly with B. c. sub.sp. oleifera var. toria. Sporocytes of the two hybrids were studied at meiosis. The presence of one or two quadrivalents in the first hybrid and two trivalents in the second suggested that allosyndetic recombination had occurred in the 18-chromosome hybrid. The progeny was presumed to have arisen through pseudo-diploid parthenogenesis and this in association with allosyndetic recombination may provide a means of breeding higher yielding genotypes.

Type
Research Article
Information
Genetics Research , Volume 21 , Issue 2 , April 1973 , pp. 133 - 137
Copyright
Copyright © Cambridge University Press 1973

References

REFERENCES

Nei, M. (1963). The efficiency of haploid method of plant breeding. Heredity 18, 95–100.CrossRefGoogle Scholar
Nwankiti, O. (1970). Cytogenetic and breeding studies with Brassica. I. Cytogenetic experiments with Brassica Napocampestris. Hereditas 66, 109–126.CrossRefGoogle Scholar
Olsson, G. (1960). Species crosses within the genus Brassica. 1. Artificial Brassica juncea Coss. Hereditas 46, 171–223.Google Scholar
Prakash, S. (1969). Production of superior amphidiploids of Brassica juncea Coss from different 20-chromosome species of Brassica, and their evaluation to certain fungal diseases. Ph.D. Thesis, Aligarh Muslim University, India.Google Scholar
Ramanujam, S. & Srinivasachar, D. (1943). Cytogenetical investigations in the genus Brassica and the artificial synthesis of Brassica juncea. Indian Journal of Genetics & Plant Breeding 3, 73–88.Google Scholar
Riley, R. & Kempanna, C. (1963). Homoeologous nature of the non-homologous meiotic pairing in Triticum aestivum deficient for chromosome V (5 B). Heredity 18, 287–306.Google Scholar
Röbbelen, G. (1960). Beitrage zur Analyse des Brassica Genoms. Chromosoma 11, 205–228.Google Scholar
U, N., Mizushima, U. & Saito, K. (1937). On diploid and triploid Brassica-Raphanus hybrids. Cytologia 8, 319–326.Google Scholar