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

and <strong>plant</strong> <strong>height</strong> c lasse s .
Root growth rates were calcu]ated as the sum <strong>of</strong>, root
dry weight at sampting L, 2, 3, 4, J, and 6 nrultiplied by
respective weightings <strong>of</strong> 6. 5, 4, 3, 2. ând 1. Genotypes
were then compared for these parameters.
Rank correlations were computed among the paraneters
for maximum root dry weight and root growth rate with <strong>plant</strong>
<strong>height</strong>, yield, 200 kernel we ight and percent plumpness, and.
with eaeh other.
This experiment was designed to c ompare seleeted semi-
dwarf and ta1l genotypes for the abil-ity to emerge fron:
various <strong>plant</strong>ing depths. The genotype s used are deseribed
in lable J.
A three-repficate completely randomized block desígn
experinent was grown in a l:1:1 soi1, sand, and peat moss
nedium in boxes in the greenhouse in l-975, Planting depths
\\tere 2,54, 5,O8, ? .62 and 10.16 cm.
Emergence rate indexes (ÉRI) were calculated by the
method deseribed by A.11an et. aI. (f962).
Lnalysis <strong>of</strong> variance was used to determine genotypie
differences. the relationship <strong>of</strong> ERI to <strong>plant</strong> <strong>height</strong>,
coleoptile length, yieId, 200 kernel weight, and percent
plurnpness was studied by rank correlation procedures.
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