Page 8 - Molecular Plant Breeding

Molecular Plant Breeding 2013, Vol.5, No.7, 36-42
http://mpb.biopublisher.ca
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higher in 2+12 wheats and the increase was also linear
(Figure 2), similar impact was also noticed in the
bread quality (Figure 6). Response to protein content
in bread quality was also linear in 2+12 wheats (R2:
0.145) whereas the relationship was not only
weakened in 5+10 (R2: 0.06). It states that very high
protein levels in 5+10 wheats are no guarantee of
enhanced wet gluten levels and improved bread quality.
Figure 6 Relationship of grain protein content with bread quality
Grain hardness also exhibited peculiar pattern in
quality of chapati and cookies. For good chapati,
wheats of hard grain texture are preferred (Pena, 2011;
Mohan and Gupta, 2013a). Interestingly, such
association in chapati could only be observed in 2+12
wheats (Figure 7). Trend was reverse in 5+10 category
but in the light of low R2 value, it could not be
confirmed. It shows that capacity of absorbing more
water in harder grains prevail only in 2+12 wheats
which brings more puffing and elevates chapati
quality. In biscuit spread factor, undoubtedly grain
hardness lowered the biscuit spread factor. Since soft
grain wheats could only be noticed in 2+12 wheats,
the trend could also be validated only in 2+12 group.
Figure 7 Response of grain hardness in quality of chapati and
cookies
2 Discussion and Conclusion
Global warming is a global phenomenon and the study
convincingly demonstrates that alterations in protein
fractions in wheat, especially at Glu D1 locus, shall be
a major concern in grain quality. At places where
wheat has un-favouring growth conditions; frequency
of 2+12 shall go higher among the high yielders and
such changes can be expected all over the world.
Since dough quality of 2+12 wheats is lower in
comparison to 5+10 wheats (Payne et al., 1987;
Horvat et al., 2002; Pena, 2011), erosion in product
quality is most likely under changing climate. In
counties like India where wheat cultivars are generally
low in strength and quality of gluten (Mohan et al.,
2013b), effect on dough quality can be even more
severe. Even though decline in dough quality of 2+12
wheats enrooted through lower sedimentation volume
and gluten index was obvious, reduction in genotypic
variability of such traits was also illustrated in this
study. However, better wet gluten content per unit
protein higher variations for such components in 2+12
wheats do ensure opportunity of picking up good
product making genotypes. Since genotypes of
superior bread or chapati making were traced in both
categories of wheat, it implies that varieties good for
product making can be developed in the era of global
warming but the route to develop such genotypes may
undergo a change. Under such situations, it shall be
easier to exploit gluten content in comparison to
gluten strength and gluten index.
It is apparent that effect of global warming on wheat
quality can assume different dimensions depending
upon the genetic materials and the surrounding
environment. Reduction in crop duration has been
envisaged by Ortiz et al. (2008) but the late sown
genotypes which have shorter duration had not shown
any major disadvantage in AICW&BIP, except some
reduction in grain size and yellow pigments content
(Mohan et al., 2011). Instead, reduced grain size in
short duration varieties resulted in better grain protein
content or even bread quality. There are three major
components affecting the dough quality i.e. gluten
content, gluten strength and gluten quality; and
contribution of these grain properties in end-product
quality varying according to cultivars, climate and
other growth conditions. Any impact of climate
change depends upon the prominent component
articulating product quality in a given condition. At