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Seeds harvested from the greenhouse planting were used
for milling and dough-mixing tests. Seed samples were
tempered to 12.5% moisture content and milled on the C.W.
Brabender Quadrumat "Jr." Experimental Mill2)
with the sieve removed. The milled stock was separated on an
auxiliary sieve shaker with 40, 60, and 100 mesh sieves.
AACC Method 50-10 (1962) was used to determine particle size
distribution of the 100 mesh flour. Mass median particle
diameters (MMD) were calculated. The MMD is the point at
which 50% of the flour by weight is finer and 50%
coarser.
One-gram samples were analyzed for nitrogen by AACC method
46-12 (1962) and protein percentages were calculated from
percent N x 5.73.
Flour from the 60 and 100 mesh sieves was composited for
mixogram tests. Dough-mixing curves were recorded at 25C
with the Swanson-Working Mixograph2) using 30g of
flour, with absorptions adjusted to optimum for bread
dough.
Results and Discussion
The identity test with the Cinese Spring 1D ditelosomic
stock indicated that the Cheyenne chromosome substituted in
the new line was 1D.
Data for kernel and flour characteristics of the new
Cheyenne 1D substitution in Chinese Spring, the parental
cultivars, and the "1D" substitution line appear in
Table 1, and mixing curves in
Figure 1.
Kernel length and weight were somewhat greater for Cheyenne
than for Chinese Spring, but kernel width was similar in the
two cultivars. The kernel weights and lengths of the 1D
sublines were more like Chinese Spring than Cheyenne. The
"1D" line matured about 1 month later than the other
materials, and its kernel weight and width were reduced
because of high temperatures in the greenhouse during early
summer. The 1D sublines tended to be closer to Chinese
Spring than to Cheyenne in flour yield and MMD values, and
lower than either parent in percent protein. However, they
resembled Cheyenne in having the desirable properties of
increased mixing time and tolerance. The "1D" line, on the
other hand, was inferior to Chinese Spring in mixing time
and tolerance, as it had been in previous tests (MORRIS
et al. 1966).
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