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

Experiment lV: _-.t0qlepptite leneth Stuqy
This experiment was conducted to determine the relation-
ship between eoleoptite length and <strong>plant</strong> <strong>height</strong> in seleeted
taIl and semí-dwarf barley genotypes described in Tabte J.
Four semi-dwarf and three tall genotln)es were lncluded.
The study was conducted at the Universíty <strong>of</strong> Minnesota,
U.S.A. in February, 1976. A four replicate conpletely
randomized block design was used, each replicate consisting
<strong>of</strong> six seeds <strong>of</strong> each genotype individually pi.aced embryo
upright ín the center <strong>of</strong> a paper towel" This towel was
then rolled up, fastened, placed in a beaker containing
water and placed ín a dark incubator for germination. Síx
seeds were used to insure a sarnple size <strong>of</strong> five for each
replicate <strong>of</strong> each genotype" The incubator was kept at 15
degrees C for seven days, but due to this temperature, germination
did not ensue and the temperature was raised to 2j
deg"ees C for seven more days. After this, the material was
removed and the following measurenents were taken:
(1) Coleoptile ]-ength (mm.).
(2) Seminal root number"
(3) Root score - based on a visual rating in which
roots were scored as l-ong, medium, or short. lhese
were given weights <strong>of</strong> three, two and one respectively,
with the sum constituting the total- score.
( 4) sfroot length ( rnm. ) .
Analyses <strong>of</strong> variance were computed to determine dif-
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