An Overview of Omics for Wheat Grain Quality Improvement - Crop Improvement: New Approaches and Modern Techniques - page 305

quality presented in this chapter provide ample information to the underlying gene
networks controlling quality traits thereby addressing the challenges of the brisk
changes prevalent within the wheat based food systems. Aiding the exploitation
of novel genome diversity for quality value addition, research has benefitted from
the unique germplasm resource generated by synthesizing wheat from genomic/
allelic variability residing in the wheat progenitor accessional resource. These
under-utilized diploid wheat progenitor accessions are a promising conduit to wheat
productivity enhancement and the novel genomic resource contributing to wheat
quality as elucidated here.
Introduction
Bread wheat ( Triticum aestivum ) is one of the most important crop species, with
global annual production currently over 600 million tonnes providing approximately
one fifth of the world's total calorific input (FAO 2009 ). Continually raising the
yield potential of wheat to match human population growth and stabilizing yield
against the damaging effects of climate change is a top priority for agricultural sci-
ence (Reynolds et al. 2009 ). The multitude demands of variable wheat products are
challenging to fulfill in a scenario of maintaining competitiveness in international
marketplace. Especially, in the most rapidly growing markets of South-Asia and
China where the grain quality improvement has a critical role to play in establish-
ing the linkages with customers. The traditional quality aspects of wheat need to be
evolved due to the advent of new processing technologies and changes in the market
place resulting from the striking demographic changes in the region. The integration
of several disciplines like functional genomics, biotechnology and exploitation of
the genetic resources is stimulating the identification of genetic, biochemical and
physiological basis of quality encoding traits in wheat. The ongoing activities for
wheat quality improvement aim to address the major challenge of capturing the
information from both wheat and model organisms, such as rice and Arabidopsis ,
in order to define genes that underpin the unique quality attributes of wheat. The re-
sources being developed using biotechnology, comparative and functional genom-
ics include comprehensive mapping initiatives, genome-wide expression studies
and exploring the molecular basis of quality characteristics. The linkage of large
information generated from these tools need to be incorporated in wheat-breeding
programs in conjunction with high-throughput screening in order to provide the
solution to efficiently develop new, improved quality wheat varieties.
Grain yield and quality, both are determined by the size and composition of
wheat endosperm. Biochemical and genetic studies in the past three decades have
considerably increased the understanding of genetics, structure and composition of
different proteins stored in endosperm which highly influence end-use quality traits
(Ma et al. 2007). Wheat storage proteins include glutenins, gliadins, secalins and
puroindolines within endosperm which largely determine the rheological properties
of wheat flour, the most important quality attribute. Additionally the mineral and