The role of strigolactones in resistance, tolerance and control of Striga infection in Sorghum

In sub-Saharan Africa the root-parasitic weed Striga, is among the most serious pests attacking the main grain crops. Satisfactory control is still out of reach and Striga is considered a threat to food security in the region. Resistance and tolerance to this parasite are valuable traits to reduce the burden. For germination, Striga seeds require the presence of strigolactones (SLs), a plant hormone and signaling molecules that is secreted by the host into the rhizosphere. In his thesis, using a combination of lab, greenhouse and field experiments, Nasreldin Mohemed investigated the role of SL composition and amount in Striga control in sorghum. In addition, he assessed the role of SLs in the suitability of millet, sesame and groundnuts as rotation and/or trap crop to reduce infection of sorghum by Striga and control its seed bank. He found a number of SLs that have not been reported before in these inter/rotation crops, thus explaining their suitability for Striga control and showed that in sorghum strigolactone composition is linked to low germination resistance as well as tolerance to Striga. This knowledge will provide the basis needed for further improving Striga resistance, tolerance and control in the important African staple food sorghum.