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

sístent suppLy <strong>of</strong> adeguate noisture. I,or the dryer areas,
in fact, semi-dwarfs nay. be at a disadvantage Ín yield
relative to tall cultivars, and nay aLso be undesirably
short for modern harvesting procedures. It was observed.
that the short statured materLal investigated performed
relatively better under eonditions <strong>of</strong> adequate to high
rnoisture.
lhe trend for improved performance <strong>of</strong> the semi_dwarf
at narrow row spacings and high seedjlg rates again refleeted
thelr laek <strong>of</strong> conpetitíve ability. Row spacång would not
present a serious problea to the producer since the narrovi¡est
one in the study ís the c ommon row width used by producers.
SeedÍng rate can be easily altered, but would raiee costs
sLÍghtIy.
lhe seeding rate and row spacing effeets need to be
considered in reLation to the nitrogen responses obtained"
rt seems probable that, had the nitrogen trÍals been carried
out ât greater prant densitles, the semi-dwarfs would have
shown greater response than the taLls, particularly íf
severity <strong>of</strong> lodgÍng had been accentuåted.
The seeding rate and row spacing results may also have
implications regardÍng the procedures used in the er¡aluation
<strong>of</strong> genotypes for purposes <strong>of</strong> varletal release. fhis is
especial.J.y so when the shorter types are being evaluated slde
by side wÍth tall genotypes as is now the general case.
Also, for ease <strong>of</strong> handllng, several institutions use ror¡v
spacings which rnay not alr.ow the se¡ni-dwarfs to express
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