Exploiting SNPs for biallelic CRISPR mutations in the outcrossing woody perennial Populus reveals 4-coumarate:CoA ligase specificity and redundancy

Application of genomics-assisted breeding for generation of climate resilient crops: progress and prospects

Climate change affects agricultural productivity worldwide. Increased prices of food commodities are the initial indication of drastic edible yield loss, which is expected to increase further due to global warming. This situation has compelled plant scientists to develop climate change-resilient crops, which can withstand broad-spectrum stresses such as drought, heat, cold, salinity, flood, submergence and pests, thus helping to deliver increased productivity. Genomics appears to be a promising tool for deciphering the stress responsiveness of crop species with adaptation traits or in wild relatives toward identifying underlying genes, alleles or quantitative trait loci. Molecular breeding approaches have proven helpful in enhancing the stress adaptation of crop plants, and recent advances in high-throughput sequencing and phenotyping platforms have transformed molecular breeding to genomics-assisted breeding (GAB). In view of this, the present review elaborates the progress and prospects of GAB for improving climate change resilience in crops, which is likely to play an ever increasing role in the effort to ensure global food security.

CRISPRing into the woods

The CRISPR/Cas9 technology is a welcome breakthrough for genome editing, owing to its precision, efficiency, versatility and ease of adoption. We recently reported the first application of CRISPR/Cas9 for biallelic mutations in stably transformed Populus, extending the species range of this powerful technology to woody perennials. An underappreciated obstacle in genome editing of outcrossing species is the frequent occurrence of sequence polymorphisms that can render CRISPR/Cas9 unproductive. We discuss experimental evidence as well as genome-wide computational analysis to demonstrate the sensitivity of CRISPR/Cas9 to allelic heterozygosity, and highlight tools and strategies that can help deal with such sequence polymorphisms. With its specificity, CRISPR/Cas9 offers a less equivocal means than previous approaches for discerning functional redundancy of paralogous genes that are prevalent in plant genomes. Continuing improvements of the CRISPR/Cas9 system for multiplex genome engineering should facilitate these efforts. The paradigm shift brought about by CRISPR/Cas9 promises to accelerate not only basic research but also applied crop improvement progress.