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

In the United States the barley breeding project at
the University <strong>of</strong> Mínne sota has been the most successful
in developing semi-dwarf genotypes, utilizing a semi-dwarf
source produced by irradiation <strong>of</strong> the Norwegian cultivar
"Jotun' at the Norwegían Gol.Lege <strong>of</strong> Agriculture, VollebeJ-sk,
Norway.
This project has registered M21 and M22' two germplasms
with good agronomic performance and adapted to the mid-
western and northern barley growing areas <strong>of</strong> the United
States (Rasmusson et al. , L9?3),
This sarne source <strong>of</strong> short straw has been utilízed to
develop types adapted to the Canadian prairies by the
bartey project group at the University <strong>of</strong> Saskatchewan in
Saskatoon. Germplasm from both these institutions is being
utilized at several locations throughout North Ameríca.
Heritabi-lity and Selection
fhe <strong>plant</strong> breeder is faced with the task <strong>of</strong> exploiting
the available genetic variabilíty and avoiding or modifying
undesirable character associations in order to develop a
genotype which has some advantâge over presently available
ones and is both agronomically and commercially acceptable.
îo exploit the available variability one must impose some
type <strong>of</strong> selection. Since most agronomically ímportant
characters are quantitatively inherited, and therefore
greatly ínfluenced by environmental conditions (Fiuzat and
Atkíns, ]-g53), one needs ã measurement to determine the
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