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

Kernel Weight
Added N had little effect on kernel weight after the
first N incrernent, at all sites except Sanford. There,
kernel weight became progressively lo'er with added incre_
ments <strong>of</strong> applied N.
Yield cornponent compensation was again in evidenee.
As the spíkes per unit area and kernels per spike increased
wÍth increasing N, kernel weight was <strong>reduced</strong>.
0n a <strong>height</strong> class basis the semi_dwarfs had inferíor
kerne] weight, particularLy when compared to Bonanza. ![ithin
the semi-dwarfs kernels per head appeared to have more
effect on kernel_ weight reduction than spikes per unit area,
since the genotype s with more kernels per head had the lowest
kernel weight.
lhe F x G interaction at Sanford indicateä that C?O3O3Z
and Minn64-62 were more susceptable to loss <strong>of</strong> kernel weight
as N increased than was the high yielding Bonanza. this
occwred despite the fact that both these genotype s had
lower numbers <strong>of</strong> kernels per head than Bonanza at that site,
suggesting that kernel weight was the yield component whieh
must be irnproved ín these lines to bring then to eonpetitive
yield levels under these conditions. rt was ar-so a reflection
<strong>of</strong> the larger number <strong>of</strong> spikes per unit area <strong>of</strong> those genotypes.
ïn general, the specifle yÍe1d. cornponents involved in
the yield component compensatl_on varied depending on the
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