Effects of reduced plant height on breeding requirements and ...

Testing et one site for one year was judged to be
sufficie¡rt to estimate genotypic r¡aiu.es foz, heigirt, kernel
weight and lodging in the naterial stud_ted, whil-e test
weight, piurnpne ss and kernels per spike required more than
one years data. Heading date, naturity and days ín post-
anthesis required d.ata from at least two r-oeations in two
years. Yield showed evidence <strong>of</strong> a requirement <strong>of</strong> testíng
in more than one location in more than one yearo i{ore
replieation would have like1y improved the estimates for
all charac"i;ers, trut would have been partic ularly benefÍcíal
for kernels per. spíke, kernel wel-ght, maturity and lodging.
All three populations studied contained genotypes
superior to the control for each characterj.stic studied.
fhe highest yielding short statured lines from these pop_
ulations were <strong>of</strong> intermediate <strong>plant</strong> <strong>height</strong> relative to the
semi-dwarf lulirn64-62 and the tall control, the most commoniy
gr own well adapted tall var.iety <strong>of</strong> the region, ',Bonar¡.zar'.
À11 sígnificant associations with <strong>reduced</strong> <strong>plant</strong> <strong>height</strong>
were u.rde sirable with the exception <strong>of</strong> lodging" However,
the correlations, despite beÍng significant, were not large,
and it should be possì ble i;o select acceptable shorter genotypes.
c-7o-3 was the rnost promising population studied in
that regard, but more because <strong>of</strong> prevalence <strong>of</strong> short lines
than because <strong>of</strong> character i¡lterre lationships "
Reduced <strong>plant</strong> heíght had no detectable effect on the
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