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Recent technological advances in next-generation sequencing (NGS) technologies have dramatically reduced the cost of DNA sequencing, allowing species with large and complex genomes to be sequenced. Although bread wheat (Triticum aestivum L.) is one of the world's most important food crops, efficient exploitation of molecular marker-assisted breeding approaches has lagged behind that achieved in other crop species, due to its large polyploid genome. However, an international public-private effort spanning 9 years reported over 65% draft genome of bread wheat in 2014, and finally, after more than a decade culminated in the release of a gold-standard, fully annotated reference wheat-genome assembly in 2018. Shortly thereafter, in 2020, the genome of assemblies of additional 15 global wheat accessions was released. As a result, wheat has now entered into the pan-genomic era, where basic resources can be efficiently exploited. Wheat genotyping with a few hundred markers has been replaced by genotyping arrays, capable of characterizing hundreds of wheat lines, using thousands of markers, providing fast, relatively inexpensive, and reliable data for exploitation in wheat breeding. These advances have opened up new opportunities for marker-assisted selection (MAS) and genomic selection (GS) in wheat. Herein, we review the advances and perspectives in wheat genetics and genomics, with a focus on key traits, including grain yield, yield-related traits, end-use quality, and resistance to biotic and abiotic stresses. We also focus on reported candidate genes cloned and linked to traits of interest. Furthermore, we report on the improvement in the aforementioned quantitative traits, through the use of (i) clustered regularly interspaced short-palindromic repeats/CRISPR-associated protein 9 (CRISPR/Cas9)-mediated gene-editing and (ii) positional cloning methods, and of genomic selection. Finally, we examine the utilization of genomics for the next-generation wheat breeding, providing a practical example of using in silico bioinformatics tools that are based on the wheat reference-genome sequence.

The clustered regularly interspaced short palindromic repeats/CRISPR-associated protein 9 (CRISPR/Cas9) system uses single-guide RNAs for genome editing, making it a simple, robust, powerful tool for targeted gene mutagenesis, knockout and knock-in/replacement, as well as transcriptional regulation. Here, we review the working principles, components and potential modifications of CRISPR/Cas9 for efficient single and multiplex gene editing in plants. We also describe recent work that has used CRISPR/Cas9 to improve economically important traits in crop plants. Although the apparent ease of CRISPR/Cas9-mediated editing may make it appear as though scientists are merely playing with plant genomes, the combined power of CRISPR/Cas9 has enabled vital research to be completed in the battle toward optimization and adaptation of crop species, permitting crucial advances to be achieved in crop improvement. [ABSTRACT FROM AUTHOR]

A high concentration of toxic heavy metal cadmium (Cd) in the paddy soils and its translocation and subsequent accumulation in the rice grain and the food chain is a global environmental issue. Mechanistic understanding of soil properties that affects the uptake and translocation of Cd in rice may help to reduce Cd uptake by rice plants and its accumulation in the grains. This review discusses the known and unknown soil and plant factors involved in the transportation of Cd from the soil through roots into rice grains. Various management practices to remediate Cd from contaminated soil are known, but only a few of these technologies are practically applicable in the field. The use of effective, ecofriendly, and natural resource-based remediation practices and understanding of their underlying mechanism is indispensable. The translocation of Cd from soil to rice roots may be reduced by controlling soil pH and redox potential through wise management of nutrients and water. The uptake and translocation of Cd and its accumulation in rice grains may be reduced by developing genotypes restricting Cd uptake. This can be achieved through breeding and identifying Cd tolerant genes followed by knocking out and/or editing these genes via CRISPR/Cas9 technique. Image 1 • A high grain Cd concentration is a global environmental and health issue. • The grain Cd accumulation may be reduced by wise nutrient and water management. • Developing low Cd acquiring genotypes can reduce Cd uptake and grain accumulation. [ABSTRACT FROM AUTHOR]