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Some agronomic characters and grain
protein content of Chinese Spring monosomics and
ditelosomics1)
H. YOSHIDA and K. KAWAGUCHI
National Agricultural Research Center, Tsukuba 305,
Japan
Aneuploid series of Triticum aestivum var. Chinese
Spring developed by SEARS (1954, 1978) have been available
to reduce the complexity of genetic analysis in hexaploid
wheat. In the Japanese wheat breeding, it is particularly
necessary to grasp the chromosome location of the loci
influencing heading time, yield components and grain protein
content. Here the chromosomal contribution in the
representation of some agronomic characters and grain
protein content was estimated by making a comparison between
the phenotypic variability of either Chinese Spring
monosomics or ditelosomics and that of the normal
disomics.
Materials and Methods
The materials for the present study comprised of 21 Chinese
Spring monosomic lines, 31 telosomic lines listed in
Table 2 and the disomics. Their
seeds were kindly obtained from Prof. K. NISHIKAWA Of
Faculty of Agriculture, Gifu University, Japan.
Three seedlings a line were transplanted with a spacing of
60 x 10 cm in the alluvial soil field at the beginning of
December in 1975 and 1976. On the other hand, three seeds a
line were sown in 1/2000a size-pot, and then grown outdoors
after the growth of seedlings during 3 weeks in the
greenhouse in parallel with the field. Although the
chromosomes of their lines were not identified, there seems
to be no problem in the most lines because they are stable,
excepting monotelodisomic 1AS, 4ABeta and 5AS, ditelosomic
2AS and ditelo 2BS-monotelosomic 2BL (personal communication
from Prof. NISHIKAWA).
The observations were recorded on the characters in
Table 1. Mean of all 3 plants for
each line was calculated except for a few lines. Based on
the field and pot trials of the two years, means of either
the monosomic or the telosomic lines were compared with the
disomic mean of 6 plants. Grain protein content was
calculated from % nitrogen of 500 mg grain flour samples
measured by autoanalyzer (Technicon Co., Ltd.) using a
factor of 5.7. The samples were milled with grains of 1975
cultivation.
Air temperature of the growing season was slowly falling
after seeding (av. temp ca. 15C), and became bottom at the
middle of January. It rose afterwards. Growth is slow but
continuous during winter, and there is no
winter-killing.
Results and Discussion
Table 1 shows the monosomic and
the telosomic lines making a representation clearly deviated
from Chinese Spring disomics on some agronomic characters.
There are some differences in characteristics between the
monosomics and the ditelosomics. This may be because of the
hemizygous effect of the genes. However, the chromosome 2A
exhibited a similar effect under both hemizygous and
homozygous conditions for culm length, spikelet number and
spike density. The monosomic 3A also was similar to the
ditelosomic 3AL for expression of 100-grains weight and
grain yield per plant.
The ditelosomic lines generally exhibited inferior
character(s) as compared with the monosomics and the
disomics. From observations on the ditelosomics of Chinese
Spring, it was concluded that deficiency of the genes
located on the chromosomes of homoeologous group 2
influenced agronomic characters for the deleterious effect,
while that of group 4 was hardly affected. This agreed with
the previous suggestion reported by ICHII & YAMAGATA
(1975).
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