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

wíth yield. fhis group discussed the irnportance <strong>of</strong> the
influence <strong>of</strong> genotypic selection in correlation studies,
índicating that the genotypes studied may bias conelation
data. fn the barley work referred to, the study <strong>of</strong> Nasr
et al., (1973) involved tal1 x short- strawed crosses, and
the short genotypes were relatively unimproved and unadapted.
Konishi's study (Konishi, l-976) involved several Japanese
short statured types and a norrnal strain <strong>of</strong> barley. He
noted that the very short types were inferior while the
"not so shortrr types were not ínferior to the normal.
Konishi stated, *For increasing total production <strong>of</strong> a dwarf
mutant, it ís necessary to have long stems to some extent,
and so irnprove the form for light interception <strong>of</strong> the <strong>plant</strong>.,n
Konishi noted that similar results had been reported for rice
by Kawai (r9Ø) in that all dwarf rice mutants which had
stems shorter than BJ percent <strong>of</strong> the original variety showed
decreased yield.
"Perhaps the most outstanding character <strong>of</strong> semi-dwarf
wheats is resistance to lodging.rt, ( Bríggle and Vogel, 1968).
this posÍtive relation between shorter straw and <strong>reduced</strong>
lodging in wheat has been supported by many observations.
This led to a statement by Klatt (I9?3), to the effect that,
pri-or to L962, pAant, <strong>height</strong> and straw weakness had limited
the yield potential <strong>of</strong> wheat, which was significantly increased
by the first semi-dwarf varieties.
Chandl-er (1969) stated that in rice, the most important
single morphological feature affecting lodging resistance i.s
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