The discovery of a gene that regulates the angle of root growth in corn is a new tool to enable the breeding of deeper-rooting crops with enhanced ability to take up nitrogen, according to an international team of researchers, led by Penn State.
The gene, called ZmCIPK15 — a moniker indicating where it is located in the genome and how it functions — was found to be missing in a naturally occurring mutant corn line that grows roots at steeper angles that make them go deeper into the soil. They identified the gene using a technique called a genome-wide association study, which involves a painstaking statistical analysis of a genome-wide set of genetic variants in different plant lines to see what genes are associated with a trait.
Identifying a gene that controls the angle of root growth in corn — influencing the depth to which roots forage — is important because deeper roots have a greater ability to capture nitrogen, according to research team leader Jonathan Lynch, distinguished professor of plant science in Penn State's College of Agricultural Sciences. Corn with an enhanced ability to take up nitrogen has implications for the world’s environment, economy and food security, he noted.
Read more at: Penn State
These images of root architecture in the field show the cipk15 mutant corn genotype had significantly steeper angles compared to the wildtype genotype. Plants were grown in low nitrogen conditions. The mutant corn line that produced the root on the right lacks a gene that regulates root growth. (Photo Credit: Hannah Schneider/Penn State)