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

was significant" fhe only case in which these interactions
t
were larger than orõ was for yield in population Ç-?A4 in
which genotype x year (Ofrr) ana genc.type x location (Cfr")
were both significant anci larger tfranOf,. This led to no
significant genotypic variance for yield in this population"
t
îhe Cõy was both more <strong>of</strong>ten significant and more con-
s!-stently signíficant across populations than wasFfr", in
agreernent with the results reported by Rasmusson and Glass
(1967)" rheefr.,' *as inportant in all populations for <strong>plant</strong>
<strong>height</strong>, 200 kernel weíght, and percent plunpness; and signíficant
às well- ín populatioris one and three for kernels
per spike, days to headÍng, days to maturity and Cays in
post-ânthesis. fheOfr" was relatively important only for
da¡'s tro heading in populations C-?0-1 anò, C-IO-Z. Rasmusson
and Glass (196?) reported no significantOfr, for <strong>plant</strong> <strong>height</strong>
in agreement with the present study, whíle they did report
a significant O[" for rlays to heading j-n one population.
ïn no case vÍere any <strong>of</strong> the interaction variance
components larger than the error component <strong>of</strong> variance (Of;).
The6!'s for test weight, kernels per spike, kernel weight,
days to maturity, and days in post-anthesis were two to
three tines as Ìarge as were tfredfr estimates for these
pârameters, and for yíeld, tire C!,s were four to nine times
greater than were tfre Ofr's. These results again are in
general agreernent wlth those reported by Rasmusson and Glass
(196?) and Rutger et al. {f966),
The heritabi-lity estirnates presented in Table ? are
59