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

short term under conditions of low temperature and humidity. The darkening
occurs due to some type of tannin reaction (Matus et al., 1993). Darkening and
differences in green lentil colour are two different problems that occur in the seed
coat but both reduce final desirability of the sample. These two problems are
unique to green lentil as they both occur in the seed coat. Other factors like staining
or the presence of disease may occur during field weathering as well. Cotyledon
colour may affect the colour perceived by acting as a background. Different hues of
green seed coats may allow the yellow cotyledon background to have some effect.
2.5 Colour in soybean (Glycine max) tissue
In soybean reproductive and vegetative tissues, green colour retention is
associated with the stay-green trait. Guiamét et al. (1991) report that the stay-green
trait does not have the same amount of chlorophyll a and chlorophyll b degradation
as compared to conventional soybean. Only about ten percent of chlorophyll loss
occurs at maturity. The stay-green trait is associated with the presence of thylakoid
proteins that are associated with both photosystem I and photosystem II. In
soybean, two loci control the trait. One locus controls the trait in leaves while the
other controls the stay-green trait in seeds. Lentil does not have the stay-green trait
but it is not yet determined if green seed coat colour loss is similar to that of
conventional soybean.
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