Researchers ID poplar tree gene that boosts photosynthesis and tree height

In Illinois, a team of scientists have identified a gene in poplar trees that enhances photosynthesis and can boost tree height. The study, “An orphan gene BOOSTER enhances photosynthetic efficiency and plant productivity,” is published in Developmental Cell, and was a collaboration between the Center for Advanced Bioenergy and Bioproducts Innovation at the University of Illinois Urbana-Champaign and the Center for Bioenergy Innovation at Oak Ridge National Laboratory.

In the new study, the researchers focused on poplar since it is a fast-growing crop and a leading candidate for making biofuels and bioproducts. They sampled ~1,000 trees in outdoor research plots and analyzed their physical characteristics and genetic makeup to perform a genome-wide association study. The team used the GWAS population to look for candidate genes that had been linked to photosynthetic quenching, a process that regulates how quickly plants adjust between sun and shade and dissipate excess energy from too much sun to avoid damage.

One of the genes, which the researchers named BOOSTER, was unusual because it is unique to poplar and although it is in the nuclear genome contains a sequence which originated from the chloroplast.

The team discovered that this gene was able to increase the Rubisco content and subsequent photosynthetic activity, resulting in taller polar plants when grown in greenhouse conditions. In field conditions, scientists found that genotypes with higher expression of BOOSTER were up to 37% taller, increasing biomass per plant.

The team also inserted BOOSTER in a different plant, Arabidopsis, or thale cress, resulting in an increase in biomass and seed production. This finding indicates the wider applicability of BOOSTER to potentially trigger higher yields in other plants.