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

yield testlng experiments. Furthermore, ít is quite probable
that, were the improvements suggesteC to reduce the levels
<strong>of</strong>Ç ' suceessful, the 1eveLs <strong>of</strong> the genoilæe by environment
interactÍon components míght inerease, motre strongly in_
dicating a need for testing over more environments " This
experiment díd not give sufficient evidence to indicate
whether the number <strong>of</strong> years and locations used were suffi_
cient to accurate).y meâ.sure the yieliting ability <strong>of</strong> these
genotJrpes, and in fact, the low heritability estimates and
their large standard errors indicate that the resurts were
not as good as might have been expected in view <strong>of</strong> the make_
up <strong>of</strong> the naterials involved.
.Tra it ComÞarisons
Plant breeders produce segregatlng populations in an
attempt not only to select the superior índlviduals, but
also to select those which are in some way superÍor to the
best available cultivar, <strong>of</strong>ten used as a control.
In the present study lines were identÍfied as superíor
to the control variety Bonanza for each <strong>of</strong> kernels per
spike, kernel- weight, test weight, plurnpness, degree <strong>of</strong>
lodging, days to heading, days to rnaturity, days in post_
anthesis, yie1d, levels <strong>of</strong> alpha-amylase, saccharifying
activity, percent barley nitrogen and soluble aroino-nitrogen.
WÍth <strong>plant</strong> treight, since selection would be for shortêr
lines, again, all three poputations contained superi.or
( shorter ) individuaLs.
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