Modern omics toolbox for producing combined and multifactorial abiotic stress tolerant plants

Plants being sessile organisms, face environmental challenges and climate change scenarios, that often occur simultaneously (as dual or multifactorial) rather than as a single stress factor. Combined stresses may exert additive impacts on plant growth and yields. The prime challenge to safely feed the burgeoning population, in light of climate change issues, demands precise agriculture systems. Though traditional breeding methods have been utilised but with limited success owing to time, cost, and infrastructure constraints. Modern biotechnological tools, especially the high-throughput omics including genomics, transcriptomics, miRNAomics, metabolomics, lipidomics beside others are being advocated to revolutionize the science of stress biology and to develop stress-smart crops. Omics tools, databases, and pipelines coupled with machine learning, artificial intelligence, and mathematical modeling are proving highly effective not only in deciphering the mechanistic insights of plant stress responses but also in enhancing the stress-tolerance. This review presents current knowledge and updates on recent developments on plant abiotic stress responses and adaptive strategies especially against combined and sequential stresses. Latest developments in omics toolbox and how they are being explored via genetic and genomic engineering, RNA-interference, microRNAs and target mimicry are discussed in detail. Recent success in deployment of biotechnological/omics technologies in modern breeding practices for producing multi-abiotic stress tolerant crops, current challenges and key questions and futuristic trends have also been discussed.