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

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Rossnagel, Brian Gordon. Ph.D., The lJniversity <strong>of</strong>
Manítoba, June , 1978. Eåfects <strong>of</strong> Redu-ced Plan-b Heieht
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on Ëreefi:!4åReq uirements and Agronomic Behaviour Ín Barlev,
llgrdeum Vu]-gare, i,. lvlajor Pr<strong>of</strong>essori Dr. S.B. Helgason.
three barley, Hordeum lg¿g3g, L., populations, each
having one semi-dwarf parent in c onmon, were inve stigated
for tv¡o years at two locations" lhe objective was to
estimate heritabilitÍes <strong>of</strong> several agronomic parameters,
their genotype by environment interactions r and their interrelationships,
with particular emphasis on <strong>plant</strong> <strong>height</strong>.
Plant <strong>height</strong> was highly heritable and adversely related to
all other agronomic tralts except lodging. The se adverse
relationships, although significant, were not strong. The
most serious drawbacks <strong>of</strong> <strong>reduced</strong> <strong>plant</strong> <strong>height</strong> were associations
with <strong>reduced</strong> kernel size parameters and late
rnatwity. Environmental Ínteractions and- their effects on
testing procedures for all- characters measured are discussed
in the manuscript, as are further character interrelation-
ships .
three seni-dwarf and two tal-1 genot¡r¡les were tested
for response to nitrogen fertilization at three locations
during two years. No genotype by fertilizer j-nteractions