RESEARCH HIGHLIGHTS

摘要

More than 500 million people in Africa depend on cassava as their main source of carbohydrates. The genetic improvement of dry matter and provitamin A carotenoid content, two of the most important traits in the crop, is impeded by their relatively considerable negative correla-tion in the germplasm of Africa. Rabbi et al. performed a genome-wide association study for the two traits in a large breeding population. They found two major loci associated with carotenoid content on chromo-some 1, one of which also co-locates with a major locus for dry matter content. The genomic region where these loci occur is characterized by a large chromosomal segment with reduced recombination rate relative to the rest of the genome. This region also contains key candidate genes for the carotenoid and carbohydrate biosynthesis pathways. Together, these findings suggest that the negative association between these important traits is largely due to genetic linkage. The authors recom-mend further investigation for confirmation. Markers linked to the dry matter and carotenoid content loci can now be deployed in breeding pipelines for marker-assisted selection.