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

Alternatively, the samples had less time to weather after harvest maturity but prior
to harvest. Due to the large range in maturity in the set of genotypes used in the
desiccation study it is not surprising therefore that there was some maturity effect
even though it only occurred in 2005. When canola is swathed before it is
physiologically mature the chlorophyll is unable to degrade in the cotyledon
(Ransom, 2006). This could be similar to lentil where there was a maturity effect
for 2005. Some of the lines were swathed too early. The seed coat appeared more
desirable than did the seed coat from a line that was swathed at the proper timing.
Lines that were swathed past optimum timing would have experienced more
weathering than other lines. The extra weathering after physiological maturity may
have explained some of the less desirable index scores for the early maturing
genotypes.
To reduce the effect of maturity, it would be better to apply treatments to
each genotype separately and harvest separately. This would eliminate the effects
of immature samples or samples that remain in the field for a period of time after
the recommended preharvest treatment stage. One disadvantage to individual
harvest is some later genotypes may be subjected to variable weather conditions like
more rainfall which would have occurred in 2005 in this study if individual
genotype harvest had been employed. The best way to attempt to eliminate maturity
factors would be to group genotypes with similar maturity so they would be
exposed to the same environments for the same length of time.
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