Cover Story (view full-size image) In the absence of BPS1 gene function, plants overproduce a mobile BPS1signaling compound in roots, and this signal arrests shoot growth and causes abnormal root development. Herein, during rhizobial symbiosis, the Phaseolus BPS1 silenced roots failed to induce cortical cell divisions without affecting the infection thread formation. This symbiosis phenotype was partially rescued by exogenous application of carotenoid biosynthesis inhibitor, as the carotenoids are the precursors of BPS1 signaling molecule. It can, therefore, be concluded that BPS1 is required for the induction of nodule primordia. Read full article