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

sma1l number <strong>of</strong> short lines j.n that population, fhe overal_L
negative association was one <strong>of</strong> the results <strong>of</strong> the observed
slower, prostrate early growth and generaLly slower d.evelop_
ment <strong>of</strong> the shorter 1ines.
îhe negative corelation between helght and naturity in
c-70-1 represented a eontinuation <strong>of</strong> the sl.wer devel0pment
<strong>of</strong> the short statured segregates. The tendency for most <strong>of</strong>
the genotype s ín c-?0-3 to ripen <strong>of</strong>f early despite heading
at about the same time as C-ZO_I gave ríse to the Lack <strong>of</strong> a
signifieant relationship in C-?O-3, The correlation for
C-7O-Z was non-significant, indicating that the dlfferences
in naturity in that population were not reÌated to <strong>height</strong>
differences.
The generalty negative relatíonshíps <strong>of</strong> <strong>height</strong> with
heading and maturity, as well as the observed slower develop_
ment <strong>of</strong> the short statured lines, combined wlth the fact
that the sení-dwarf parent headed and matured ì.ater, suggested
linkage between these p4¡¿¡¡sters arld <strong>height</strong> in this
naterial. Followíng ín the same rrein, the tendency for much
af C-7O-3 to ripen <strong>of</strong>f under stress was the habit <strong>of</strong> the
taller parent in that cross.
The conslstent posl-tíve association <strong>of</strong> <strong>height</strong> with days
in post-anthesis resulted primariry from the late heading <strong>of</strong>
the shorter materials wÍthout proportionate delays in maturity.
The ímportance <strong>of</strong> this association nay be in the
association <strong>of</strong> short stature with <strong>reduced</strong>. kernel size.
The absence <strong>of</strong> any signifícant eoruelations between
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