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Excess Ni intake has harmful implications on human health, which include chronic bronchitis, reduced lung function, and cancer of lung and nasal sinuses. Like other toxic metals, higher Ni accumulation in grains leads to excess intake by humans when the contaminated grains are consumed as food. There is little information about the genetic factors that regulate Ni uptake in plants. To investigate genetic architecture of Ni uptake in leaf and translocation to grain, we performed a genome-wide association study with genotyping from 90 K array in a historical bread wheat diversity panel from Pakistan. We observed that Ni toxicity caused more than 50 % reductions in biological yield and grain yield, other agronomic traits were also partly or severely affected. Genetic association study helped identify 23 SNP-trait associations involved in Ni uptake in leaf and translocation to grains. These 23 SNPs covered 15 genomic loci at chromosomes 1A, 2D, 3B, 4A and 4B of wheat. The favorable alleles of these SNPs were randomly distributed in subpopulations indicating no selection pressure for this trait during breeding improvement. These regions had 283 low-confidence and 248 high-confidence protein coding genes. Among these, 156 were annotated using databases of wheat and closely related grass species. Since there is no previous report on genetic information of Ni uptake and translocation, these results provide sufficient grounds for further research of candidate genes and varietal development.

The linked projections of the global population standing in 2050 of approximately 9.2 billion and the balanced annual increase in crop yields to ensure food security, with wheat considered as its major conduit have necessitated taking a careful multidisciplinary integrated look at what looms ahead. Keeping wheat as the major crop target, its outputs under irrigated and rain-fed conditions have become significant to address factors that pave the way for yield maximization both under plant improvement and plant management scenarios. Optimum experimental condition yields and realized national annual yields show tremendous gaps, and when farmers with smaller land holdings are involved, this gap is further broadened. In this chapter, we address yield discrepancies, focusing on drought due to three major factors present now and that may magnify in the future; this suggests the need to embrace all as working objectives in a tandem manner and in a holistic fashion. The genetic component has a pivotal slot that encompasses breeding for high yield per se and, where such genetic resource diversity is limiting, to explore the various wheat gene pools and harness the same. This option may permit researchers to capture the diversity of genetic resources that have so far been underutilized over an expanse that covers intraspecific, interspecific, and intergeneric hybridization. The working expanse addresses both biotic and abiotic stress production constraints and allows more precise handling of crop improvement around water-limiting conditions. Intervention using current molecular advances is a boon to swift progress. As with the exploitation of genomic diversity in prebreeding and breeding programs, the current setup may show the way forward to rely on genotypic platforms through accurate phenotypic information, thereby permitting stringent and reliable information for maximizing yields and other attributes essential for crop production to be gathered. This is where the various “omic” areas stand to efficiently support diverse research targets. Finally, it is paramount that water availability be seriously kept in focus. Timely natural supplies are risky, optimum availability for irrigating crops is showing less reliability, and water scarcity is acutely apparent; in addition, it is expected to become a major concern in the very near decades due to climate change and source supply shortages. Therefore alternatives for water provision are gaining importance coupled with the introduction of efficient management application systems. These interlinked facets form the contents of this chapter.