GREEN SEED COAT COLOUR RETENTION IN LENTIL - University ...

index score was not equal for each genotype. CDC Glamis, CDC Plato, CDC
Sovereign, and 1048-8R all had decreases in the mean index score in 2006 of at
least 1.0 when desiccation was compared to swathing. CDC Viceroy, CDC
Milestone, and 1294M-23 all had decreases in the mean index score of less than 0.3
when desiccation was compared to swathing.
There is little literature on the effects of swathing or desiccation based on
the seed coat colour of any crop. In literature for canola it was not expected that a
large difference would occur in desirable green seed coat colour from swathing to
desiccation, assuming similar mechanisms control canola cotyledon degreening and
green seed coat colour differences in lentil. Cenkowski et al. (1989b) reported that
swathing in canola does not reduce chlorophyll content in cotyledons compared to
leaving the crop standing. The possibility exists that early swathing in lentil may
produce a more desired green seed coat.
5.3.2 Maturity
The maturity rating of the plots using the scale described in Table 5.3 was
well documented prior to the preharvest treatments being applied. The regression of
the mean index score for genotype and maturity at the preharvest timing is shown in
Figures 5.3 and 5.4, for 2005 and 2006 respectively. In 2005 the regression was
significant with an R 2 = 0.20. As maturity rating increased a more desirable green
lentil sample was produced (Figure 5.3). The maturity range in 2005 was much
smaller than 2006. For 2006 the regression between maturity and index score was
not significant (Figure 5.4).
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