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

from varyíng seeding rates in barley (Middleton et at.,
1964i Bockstaele and Maddens, I966i îin]¿y et al., Ig?L),
in oats (Jones and Hayes, 196?) Folkins and Kaufmann,
L974), or in wheat (nl-Hattab et al. , IgZa; Furrer and
Stauffer, 1970; Fisctrer e-!.4.., Ig76). Woodward (1956)
reported the same results workj-ng with al_1 three cereals.
These results as such were due to either the experiment
covering only a narrow range <strong>of</strong> seed.ing rates or compensa-
ti-on among yield cornponents.
Guitard et at. (i-g6f) reported a linear increase ín
yield up to an optiraun seeding rate in wheat, oats and
barley, with a significant decrease in wheat and barley
yields at very high seeding rates. Briggs (fg?5) also
reported an increased wheat yield with increased seeding
rate over the range <strong>of</strong> rates usea (33.6 to 100.p Xe./na.),
Kirby (196?) reported lower barley yields at very high ptant
densities. McFadden (1970) reported an optimum seed.ing rate
for two barley cultivars, both above and beLow which yields
dropped. Símilar results have been reported by Woodward
(1956) and Vlilley and Holliday (19?1). young and Bauer
(1971) reported a significant yÍeld increase when they
doubled the seeding rate in a barley trial¡ however, the
origi-nal rate was a relatively low one. Zeídan (f9?4)
reported a significant yietd decrease i-n wheat at higher
<strong>plant</strong> densitie s .
0n the other hand, Pelton (1969), working with wheat in
the dry area <strong>of</strong> south-western Saskatchewan, ¡spsrted that
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