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The chromosomal locations of genes for wheat characters
have been reported by numerous workers and summarized by
AUSEMUS et al. (1967), MCINTOSH (1973, 1978) and
LELLEY (1976). The present results could pointed out in
respect of the respective characters as follows.
Vigor : The ditelosomic lines, 2BL, 3AS, 6BS, 6DL and
monosomic 5A, 5D were growing with poor vigor. Their growth
were delayed.
Heading time : Although heading time depends on
daylength and temperature, the result is shown in Table
1. It is known that the three members of homoeologous
group 5 possess the genes affecting heading time (SEARS 1954
; DRISCOLL & JENSEN 1964). The lines 5BL and 5DL were
delayed, while the line 5AL was similar to disomics.
Culm length : The missing arms of homoeologous group
2, i.e. 2AL, 2BS and 2DL were associated with
dwarfness.
No. tillers : The long and short arms of chromosome
7B showed opposite effect to each other for tillering. BHAT
& GOUD (1979) reported that the monosomic population 7B
had a gene for increased tiller number. A tillering
controlling gene seems to be located on the chromosome 7B.
The chromosome IB showed opposite effect for tillering
between the monosomic and the ditelosomic.
Spike length : Spike length of the line 3AS was about
30 per cent less than normal. It is observed that the
chromosome 3A shortens spike (BHAT & GOUD 1979).
No. spikelets : The ditelosomic line 2AS and the
monosomic line 2A had less number of spikelets. The
chromosome 2A is reported for effect on spikelet number
(SINGHAL & SINGH 1981).
Spikelet density : The ditelosomic lines, 2AL and 2DS
lay lax in spike density. They had spikes about one-half
normal density. The monosomic line 2A also reduced around 20
per cent in the density.
100-grains weight : The comparative observations
indicated that the absence of the short arm chromosomes of
homoeologous group 3 carried the increase in 100-grains
weight. The absence of the short arms of chromosomes 2B and
6D were associated with poor vigor, and consequently
influenced this character.
Grain yield per plant : Most of the ditelosomic and
the monosomic lines fell down the grain yield showing
variable range of reduction.
Data are presented in Table 2 for
% grain protein and its related characters from Chinese
Spring telosomic lines and the disomic control. The
ditelosomic line, 2BL showed the highest % of grain protein.
However, it was attributable to grain shrinkage. The higher
protein values were associated with low yield and/or low
grain weight. For this reason, chromosomal contribution of
protein production should be estimated by both scales of
protein content per grain and protein yield per plant. On
this basis, the lines, 1DL, 3AL, 5DL and 6DS were higher
than the disomic control for their scales. These results
suggest that the arms of chromosomes 1D, 3A, 5D and 6D, i.e.
1DS, 3AS, 5DS and 6DL possess factors which influence the
depression of protein production. This finding is in
agreement with respect to 1DL, 6DS (MATTERN et al.
1978) and 5DL (MORRIS et al. 1973). On the other
hand, FUJIWARA et al. (1977) and NAKATA et al.
(1980) have reported that there were not found differences
among Chinese Spring ditelosomic lines for protein content
after removal of influence by seed fertility. This
disagreement will be solved hereafter.
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