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

indicated by this study suggests that early_generation
selectÍon <strong>of</strong> the Larger numbers <strong>of</strong> semi-dwarfs required
would not be diffreult. fhis intense selection could then
be followed by the sorting out <strong>of</strong> other less heritable
parameters in the 1ater generations <strong>of</strong> the breeding progran.
fhe ideal genotype would have many spfkes per unit ârea,
many kernel,s per spike, high weíght per kernel and be <strong>of</strong> the
desÍred <strong>height</strong>. llowever, due to yÍeld cornponent compensation,
¡naximizatÍon <strong>of</strong> a1l three conponents in a singl"e genotype
will not be easy. From a practical standpol.nt, a reasonablê
balance <strong>of</strong> the components is desirable. rn terms <strong>of</strong> indivldual
components, kernel weíght must be at a certain
level for end use acceptabíj_ity. Kernel weight ís inportant
because heavy, pLump kernels mean l_ess fiber and more energ:y
per pound <strong>of</strong> graÍn. fhis is important both from a feed and
a malting viewpoint. High levels <strong>of</strong> the other eonponents
are obviousLy desirable, but only because <strong>of</strong> their csntribution
to yield potential,
The evÍdence obtained suggests that adverse inter-
charaeter reLationships shown would make the task <strong>of</strong> selecting
for the desired character combÍnation directly from an
initial semi-dwarf by tall cross very difficult, and perhaps
rather impractieal. It is proposed that a more realistic
approaeh woul-d be a step-wise one, whJ.ch rnight be more time
consuming, but would be more certain <strong>of</strong> success.
fhis approach involves the sinultaneous development <strong>of</strong>
two or more short-strawed genotypes with the desired leveLs
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