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

extent. Frey et al-. (1951) indicated that c or.n varieties
were recoÍürended on the basis <strong>of</strong> soil fertility as early as
1922, In terms <strong>of</strong> fertilizer x genotype interaction, their
literature review shows that fertilizer responsiveness, in
particular to nitrogen, had been investigated in wheat, oats
and barley with both positive and negative resul"ts.
Several studies since 1!Jl have j-ndicated varying resu1ts.
lforking with wheat, Beutler and Foote (f963) an¿
Syme et aL (19?6) reported significant fertilizer x variety
interactions, as did Pendleton et a1. (f9fi), Woodward (Ig56),
and Gardener and Rathgen (t9?5) working with barley. Others
reported no fertilizer x variety interaction in wheat studies
(Rhode, 1p6f¡ Bauer, L97oi McNeal et al. 1971) and in barley
tests (Kirby, 1968). Kirby (1968) indicated that he did not
uncover any interaction probabty due to a second limiting
element in the soi1. Syme (f96?), working with wheat, also
reported no sígnificant interaction, but suggested this was
due to soil problems, in thj-s case poor wâter infiltration.
It l-s apparent that the díseovery <strong>of</strong> a fertilizer x
genotype interaction is dependent on the range <strong>of</strong> genotypes
included in the study and the Levefs <strong>of</strong> several other envir-
onmental factors, especially moisture. Stanberry and Lowrey
(L965) reported that nitrogen gave a 600/, increase in me an
yield over al-1 moisture levels used, whil-e increased moisture
over all nitrogen levels gave a 36/, yiel:d increase. However,
the combination <strong>of</strong> hígh nitrogen and adequate avaiLable
rnoisture gave â mean yield increase <strong>of</strong> nore tlnan L? OOf".
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