A screen in a small flowering plant identifies compounds that alter the levels of the plant hormone strigolactone and highlights its role in light signalling pathways. The research, published in Nature Chemical Biology, could be a first step towards disrupting the invasion of parasitic plants that present a major threat to agriculture in sub-Saharan Africa.
In addition to being an important 'branching hormone' in plants, strigolactone released by plant roots serves as an invasion cue for parasitic plants from the genera Striga and Orobanche, which present a major threat to agriculture in sub-Saharan Africa.
To identify small molecule compounds that could potentially block parasitic plant infestations, Peter McCourt and colleagues used chemical genetic screening to discover cotylimides, small molecules that perturb strigolactone levels in Arabidopsis thaliana. These compounds led them to identify a link between light-signaling genes and pathways that control the levels of strigolactones in plants. Taken together, these studies identified a new role for the plant hormone strigolactone and may lead to the development of compounds that could control the growth of the parasitic plant.