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

<strong>height</strong> and the qualÍty parameters studied indicated that
reducing <strong>plant</strong> <strong>height</strong> ín barley shoul_d not adversely affect
the attainment <strong>of</strong> malting quality. However, the physical
aspects <strong>of</strong> malting quality, kernel size, plumpness and test
weíght, appear to be adverseLy affected in these semi_dwarf
genotJæe s .
The effects <strong>of</strong> <strong>plant</strong> <strong>height</strong> on the breed.ing behaviour
<strong>of</strong> the populations in questlon nay now be more c1ear. Since
the populations are struetured to give high and consistent
heritability estlmates for <strong>plant</strong> heÍght, it folLows that
any traits strongty correLatêd with <strong>height</strong> would also tend
to be highly and/or consistently heritable. such was the
case for kernel weight, test weight, plumpness, days in
post-anthesis and degree <strong>of</strong> loclging in the present study.
Tield. In the fÍnal analysis, yiel"d Ís the crltical
trait in any breeding program, and a primary eriterion ln
evaluating materiaLs for use as germplasrû.
The relationship with pLant hetght in this study Ìras
been discussed.
lhe positive association between yield and kernels per
spike is not unexpected sínce the latter is one <strong>of</strong> the
components <strong>of</strong> yie1d. yield equals the total_ weight <strong>of</strong>
kernels per unit area <strong>of</strong> crop. Therefore, if the average
welght <strong>of</strong> the kernels and the nurnber <strong>of</strong> spikes per unj.t area
remain relatively stabre, changes in the number <strong>of</strong> kerners
per spike wlll give correspondlng changes Ín yield.
In view <strong>of</strong> the positive <strong>height</strong> to yieLd. and <strong>height</strong> to
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