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Around 70 percent of crop yield losses are projected because of climate induced abiotic stresses like moisture stress, soil salinity and heat stress. Critical to the stability of cropping systems in the face of climate change is the capacity to rapidly grow germplasm with tolerance to complex polygenic inherited abiotic and biotic stresses combined. Molecular breeding provides the means to speed up cereal breeding, but adequate phenotyping protocols are required to ensure that the much-anticipated benefits of novel breeding tools can be realized. Tremendous advances in phenomics have taken place in the recent past. Both forward and reverse phenomics have developed to help determine either the best genotype with the desired feature or mechanism and the genes that make the genotype the best. High-throughput phenomics studies include techniques for screening substantial germplasm sets for a specific trait using high-throughput phenotyping (HTP) technologies like advanced robots, high-tech sensors, 3D imaging, fluorescence imaging, NIR imaging, lemnatec, etc. The high velocity of plant phenotyping based on phenomics accelerates the selection phase of potential advanced germplasm resilient towards climate induced stresses.

Drought is one of the foremost threats for global cereal crop production with looming risks due to changing climatic scenarios. Among major cereals, rice wheat and maize are commonly grown worldwide for their importance as staple food as well as significance in fulfilling the nutritional requirements among the escalating human population. Drought being a complex trait is difficult to manage through conventional breeding approaches therefore, recent advances in genomics tools has resulted in precised and targeted identification of mechanisms underlying drought stress tolerance in cereals. Further, combination of customary breeding advances with the recent high throughput genomics technologies resulted in the popularization of genomics assisted breeding. There are various marker-assisted breeding (MAB) strategies to transfer or introgress trait of interest; these include marker-assisted selection (MAS); marker-assisted introgression (MAI), MA-backcrossing (MABC), MA-recurrent selection (MARS), MA-gene pyramiding (MAGP); genome-wide selection (GWS) and genomic selection (GS). In this review, recent advances for achieving drought stress tolerance in major cereals using genomics assisted breeding (GAB) has been discussed . We begin with the genetics of drought stress traits, MAB for abiotic stress tolerance with successful examples of mapped genomic regions for drought stress tolerance in rice, wheat and maize, respectively and finally MAI of genomic regions for improvement of drought tolerance in cereals. Further, in addition to MAB, genomic selection, an advanced molecular breeding technology, have pronounced potential to improve multiple traits simultaneously including drought tolerance in cereals. DOI.10.25174/2582-2675/2020/100821