Olive quick decline syndrome (OQDS) (in Italian: Complesso da Disseccamento Rapido dell'Olivo, CDRO or CoDiRo) is a wasting disease of olive trees which causes dieback of the leaves, twigs and branches so that the trees no longer produce crops of olives. The main cause is a strain of the bacterium, Xylella fastidiosa, which is spread by plant-sucking insects such as the meadow froghopper. The bacteria restrict the flow of sap within the tree and so choke its extremities.