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Biology and Biotechnology of Environmental Stress Tolerance in Plants, Volume 3

FIGURE 10.1 The effect of environmental stress on plants and their response to the stressed

conditions.

10.3 GENOME WIDE ASSOCIATION STUDIES IN PLANTS

The overgrowing computational methods and sequencing technologies have

made GWAS a powerful tool for detecting natural variations that comes

under complex traits in crops (Rafalski, 2010). Based on linkage disequi­

librium, GWAS is a method for high-resolution mapping of complex trait

loci (Flint-Garcia et al., 2005). The connection between genetic variation

and crucial agricultural properties, such as stress tolerance, has been studied

using GWAS. Its potential for uncovering beneficial natural variants in trait-

associated loci is still in its infancy. As well as allelic variants in candidate

genes that underpin quantitative and complex variables, such as growth,

development, stress, and nutritional quality. The priority assigned to genes

selected for more intensive biochemical and physiological investigations on

the processes of stress response can be defined using candidate genes identi­

fied by GWAS. In crops, GWAS use an everlasting resource that is the popu­

lation of different varieties can be genotyped once but can be rephenotyped

many times and can generate mapping populations for specific traits or QTLs

in crops (Atwell et al., 2010). A general workflow of GWAS is demonstrated

in Figure 10.2. On the other hand, GWAS adopts a case-control design in

humans, i.e., the comparison between wide groups of patients and healthy

people can be identified with the help of population-scale genome design

that suspects loci of a particular disease. The missing heritability problem

has inclined the GWAS of humans as they identify the loci that have a very

low rate of phenotypic contribution.