Euphytica 111: 145–149, 2000.
© 2000 Kluwer Academic Publishers. Printed in the Netherlands.
145
Isolation of a fertile wheat-barley addition line carrying the entire barley
chromosome 1H
A.K.M. Rafiqul Islam & Kenneth W. Shepherd
Department of Plant Science, The University of Adelaide, Waite Campus, Glen Osmond, SA 5064, Australia
Received 14 October 1998; accepted 5 July 1999
Key words: addition line, gene mapping, meiotic abnormalities, sterility
Summary
The isolation of six of the seven possible additions of barley chromosomes to the wheat genome reported 18 years
ago has made an important contribution to gene mapping in barley, first with genes controlling isozymes and more
recently DNA (molecular) markers. A fertile addition line involving barley chromosome 1H, which carries genes
controlling several characters of economic importance, could not be isolated at that time because it caused extreme
meiotic abnormalities leading to complete sterility when added to wheat. Later the short arm of barley chromosome
1H was added to wheat as a fertile ditelosomic addition, but the non-availability of the entire barley chromosome
1H addition line has hampered the location of barley genes to the long arm of this chromosome. This problem
has now been overcome cytogenetically as described herein. The resultant self-fertile disomic-monotelodisomic
addition line carrying a pair of barley chromosome 6H and a heteromorphic 1H/1HS pair is more stable, and
makes the wheat-barley addition line series complete for gene mapping work and will provide a vehicle for the
possible transfer of useful genes from this barley chromosome to wheat.
Introduction
There has been interest in hybridizing wheat with bar-
ley for almost 100 years (Farrer, 1904), but the first
authentic hybrid between these two most important
cereal crops of temperate agriculture was not obtained
until Kruse’s success in 1973 (Kruse, 1973). Follow-
ing his work using barley as the female parent, we
were able to produce hybrids in new cultivar com-
binations (Islam et al., 1975) but more importantly
succeeded in producing the more difficult reciprocal
hybrid using wheat as the female parent (Islam et
al., 1981). Our aim was to add individual pairs of
barley chromosomes to the wheat genome for use in
barley gene mapping and possible transfer of useful
barley characters into wheat. In our earlier work we
succeeded first in isolating six of the seven possible
disomic additions of Betzes barley chromosomes 2H,
3H, 4H, 5H, 6H and 7H added to Chinese Spring
wheat (Islam et al., 1981) and later 13 of the 14
possible ditelosomic additions (Islam, 1983; Islam
& Shepherd, 1990). These disomic and ditelosomic
additions have proved to be very useful in locating
genes controlling barley proteins and isozymes (Islam
& Shepherd, 1990; Liu & Gale, 1990; Tiele & Melz,
1992) and more recently molecular markers (Cannel
et al., 1992; Graner et al., 1991; Shepherd & Islam,
1992) to individual barley chromosomes and arms.
A fertile addition line involving entire barley chro-
mosome 1H could not be produced at that time be-
cause a gene(s) present on the long arm of this chro-
mosome causes extreme cytological abnormalities at
meiosis leading to sterility, when present alone in
a wheat background (Islam et al., 1981; Islam &
Shepherd, 1990). However, when chromosome 6H is
present along with 1H in a double monosomic addi-
tion, the plants become partly female fertile and a few
backcross seeds can be obtained after pollinating them
with normal wheat and thus it has been possible to
maintain, with difficulty, this line carrying barley 1H
by selecting for double monosomic additions among
the backcross progeny in each generation. Chromo-
some 1H is of special interest to barley researchers
and breeders because it carries structural genes for