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7. Considerable intraspecific variation occurs in three
diploid species, Ae. squarrosa (Furuta et al
1975), Ae. longissima and Ae. sharonensis
(Furuta et al 1977, 1986).
8. DNA content of AB genome component of common wheat is the
same to that of T. turgidum (Furuta et al 1974) and
is similar to the sum of diploid wheat and Ae.
bicornis, Ae. searsii, Ae. longissima or
Ae. sharonensis (Furuta et al 1986).
9. The result of individual chromosomal (univalent
chromosomal) DNA content of seven strains belonging to six
subspecies of Dinkel wheat reveals variations in DNA content
between three genomes and homologous chromosomes. The ratio
of their genomic DNA content is 1.00:1.20:0.83 in A:B:D
(Furuta et al 1984).
10. Individual telocentric chromosomal DNA content in
monotelodisomic 1BS and monotelodisomic or double
telotrisomic for another chromosomes and double monotelo
1BS-1BL of al 1988).
1.00:1.12:0.82 for A:B:D, and high positive correlations
(r=0.90 and 0.99, respectively) between length and DNA
content of telosomes and DNA content of individual
chromosome and the sum of DNA of two arms for the 21
individual chromosomes (Furuta et al 1988).
All evidence mentioned above indicates no significant
reduction of genetic materials or DNA in polyploid wheat,
but the additive relationship in DNA content between
polyploid and its genome donors and suggests that relative
DNA content of the B genome in common wheat is more than
nuclear DNA content of Ae. speltoides, but comparable
to the nuclear DNA content of Ae. longissima, Ae.
searsii, Ae. bicornis or probably Ae.
sharonensis belonging to section Sitopsis of the genus
Aegilops.
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