Genomic approaches to enhance adaptive plasticity to cope with soil
constraints amidst climate change in wheat
Abstract
Climate influences on below-ground plant traits seldom receive due
attention. Climate change is varying the availability of resources, soil
physical properties, rainfall events, soil mineral weathering and
leaching intensity which collectively determines soil physical and
chemical properties. Soil constraints – acidity (pH<6),
salinity(pH≤8.5), sodicity and dispersion (pH>8.5) are
major causes of wheat yield loss in arid and semi-arid cropping systems.
To cope with changing environment, plants employ adaptive strategies
such as phenotypic plasticity; a key multifaceted trait, to promote
shifts in phenotypes. Adaptive strategies are complex, determined by key
functional traits and Genotype × Environment interactions. The
understanding of molecular basis of stress tolerance is particularly
challenging for plasticity traits. Advances in sequencing and
high-throughput genomics technologies has identified functional alleles
in gene-rich regions, haplotypes, candidate genes, mechanisms and in
silico gene expression profiles at various growth developmental stages.
Our review focuses on favourable alleles for enhanced gene expression,
QTLs and epigenetic regulation of plant responses to soil constraints
including heavy metal stress and nutrient limitations. A strategy is
then described for quantitative traits in wheat by investigating
significant alleles, functional characterization of variants, followed
by gene validation using advanced genomic tools and marker development
for molecular breeding and genome editing. Also, the review highlights
the progress of gene editing in wheat, multiplex gene editing and novel
alleles for smart control of gene expression. Integration of these
genomic technologies will be effective to enhance plasticity traits and
stabilizing wheat yields on constrained soils in the face of climate
change.