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

any specific cross. However, they did exíst, and nay have
oceurred because the longer the grain developrnent period was,
especially the latter part <strong>of</strong> that period, the more kernels
per spike actually survived. In those lines in which
maturity was forced to be earlier some kernels may not have
completed development giving rise to fewer kernels per spike,
since only completely developed kernels were eounted.
The positive relationshj_p <strong>of</strong> kernels per spike wíth
lodging occurred because those lines which lodged did so,
at least partly, because they eouldnrt support their larger
heads.
The signlficant negative associations between kernels
per spike and barley nitrogen, saceharifying activity and
soluble amino-nitrogen are surprising. As the number <strong>of</strong>
kernels per spike Ínereases, kernel size nornn lly decreases,
as was the case ín this Ëtudy, and generally higher 1evels
<strong>of</strong> these nitrogen related parameters are agsociated wíth
smaller kernels. However, as will be discussed 1ater, the
evidence in this study, ( partic uLarly from population
C-7O-2), suggested that these general relatíonshlps may
not always be as strong or consistent as is <strong>of</strong>ten presumed.
Furthermore, kernels per spike is one <strong>of</strong> the major components
<strong>of</strong> yield, and yield itself was sígníficantly negatively
related to these same three quallty paraneters in this study.
Kernel welght. The positive associatl_on <strong>of</strong> kernel
weÍght with plurnpness is indicative <strong>of</strong> size beíng due to
extension <strong>of</strong> kernel width rather than Length. The positive
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