(go to
KOMUGI Home) (go
to WIS List) (go
to NO.90 Contents)
Wheat Information Service
Number 90:31-36 (2000)
Research article
Detection of plasmon- specific RAPD markers using
the alloplasmic hybrids of common wheat (Triticum aestivum L.)
cv. Chinese Spring
Chiharu Nakamura, Masahiro, Katsuta, Torao Takeshita,
Nobuaki Asakura, Shigeo Takumi and Naoki Mori
Laboratory of Plant Genetics, Department of Biological and
Environmental Science, Faculty of Agriculture, Kobe University, 1
Rokkodai-cho, Nada-ku, Kobe 657-8501, Japan
Summary
Plasmon-specific polymorphisms were detected by RAPD-PCR analysis
of alloplasmic hybrids of common wheat (Triticum aestivum L.)
cv. Chinese Spring (CS) with cytoplasms from various Triticum
and Aegilops species. The analysis of total DNAs from 47
hybrid lines using 31 random primers revealed seven polymorphic RAPD
markers, among which six were assigned to the plasmon variations. The
polymorphic markers were either unique to single plasmons or common
to groups of phylogenetically related plasmons. By combining the
markers, at least T (Ae. mutica), T2 (Ae.
mutica), Sb (Ae. bicornis) and
A2(T. monococcum) plasmons were distinguished. They
can be effectively used for the plasmon identification of the
alloplasmic hybrids.
Key words: Plasmon-specific RAPD markers, Cytoplasm
identification, Alloplasmic hybrids, Triticum, Aegilops
Introduction
A large number of alloplasmic or nucleus-cytoplasm (NC) hybrids
have been produced through substitution backcrosses in Triticeae,
especially in Triticum and Aegilops species (Kihara
1951; Fukasawa 1953,1959; Maan 1975,1991; Tsunewaki 1980,1996;
Panayotov 1983; Ohtsuka 1981, 1991). These hybrids have provided
useful experimental materials for studying diversity of the
cytoplasmic genomes (plasmons) and interactions between nuclear
genomes and, plasmons based on the classical analysis of
physiological and morphological characteristics manifested in the
hybrids (Tsunewaki 1980, 1996) and molecular analysis of chloroplast
and mitochondrial DNA variations in the hybrids (Ogihara and
Tsunewaki 1988; Terachi and Tsunewaki 1992; Tsunewaki 1996).
One problem which did and possibly could occur during the course of
the backcross program for the production of NC hybrids is
mis-identification of lines due to mistagging. If it occurred, its
recognition and confirmation requires much time and labor as pointed
out by Tsunewaki et al. (1996). To avoid such serious problem,
molecular markers which can be easily and effectively used for the
cytoplasm identification are required. RFLP analysis of total DNA
using chloroplast and mitochondrial DNA-specific probes can be useful
for this purpose. PCR-based methodology using plasinon-specific
primers could also be useful. SSCP (single strand conformational
polymorphism) analysis in fact has been proven to be a powerful
method for the identification of both inter- and intraspecific
plasmon polymorphisms in Triticum and Aegilops species
(Ohsako et al. 1996; Wang et al. 1997).
In the present study we applied RAPD-PCR analysis which is generally
simpler and more convenient to detect DNA polymorphisms than the
above two methods. For the detection of plasmon-specific
polymorphisms we used 47 lines of NC hybrids in which one nuclear
genome of common wheat cv. Chinese Spring is combined with cytoplasms
from various Triticum and Aegilops species. Although
the scale of the present work was limited, the method was shown to be
effective in identifying polymorphisms either unique to single
particular plasmons or often common to phylogenetically related
groups of plasmons.
-->Next
(go to
KOMUGI Home) (go
to WIS List) (go
to NO.90 Contents)