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Agropyron addition lines of
durum wheat
A. MOCHIZUKI
Hyogo Agricultural College, Sasayama, Hyogo-ken, Japan
Addition of individual chromosomes of Agropyron
elongatum (2n=14, EE) to Triticum durum var.
Stewart (2n=28, AABB) has been attempted. Seven monosomic
and six disomic addition lines have successfully been
established.
The monosomic lines were produced from the pentaploid hybrid
between the amphidiploid T. durum var. Stewart x
Ag. elongatum (AABBEE) and T. durum. The
chromosome numbers in the progeny of the pentaploid hybrid
varied from 28 to 42. About 22 per cent of the progeny were
29 - chromosome plants, which had 14 pairs of wheat
chromosomes and in addition one Agropyron
chromosome.
The phenotypes of the seven monosomic addition lines were
different from T. durum due to the effect of the
alien chromosome. The 29 - chromosome plants were classified
into seven groups (e1 - e7) by their
phenotypes. Four monosomic addition lines (e1 -
e4) were frequently identified in the populations
raised every year (1958-'60), but e5 -
e7 lines rarely occurred. The transmis sion rates
of the alien chromosomes of the pentaploid hybrids were not
the same. The e1, e2, e3
and e4 chromosomes were more frequently
transmitted to the next generations than the others.
Disomic addition lines were produced in the selfed progeny
of monosomic addition lines. Monosomic addition plants
yielded three types of progeny, namely, disomic- and
monosomic-addition lines and durum wheat (2n=28).
The e6e6 disomic addition line has not
yet been obtained, although 1055 progeny plants raised from
the e6 monosomic addition line were examined. The
frequency of e6 monosomic addition plants
amounted to about 6 per cent of the above progeny. They
might be obtained by transmission of e6
chromosome through the female side. In order to obtain the
e6e6 disomic addition line, the
e6 monosomics were crossed with the original
T. durum x Ag. elolegatum amphidiploid, and 36
- chromosome plants were selected. As some of these plants
are expected to have the e6 chromosome pair in
addition to 14 wheat chromosome pairs and 6 univalents from
Agropyron (e1-e5,
e7), the e6e6 disomic
addition line may be found in their progeny.
Table 1. Phenotypes of the disomic
addition lines
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