di ALEXANDER PURCELL
The olives trees near Speccia, Italy are dead or have symptoms of Olive Quick Decline Syndrome, 2020. (Photo by Donato Boschia, with permission.)
The current epidemic of a lethal disease of olive, Olive Quick Decline Syndrome (OQDS) was first noted scientifically in 2013 near Gallipoli, Italy and continues to expand northward in Puglia1. The disease is clearly the result of a “new (recent) encounter” between olive, a plant species native to the Mediterranean basin and a bacterium, Xylella fastidiosa subspecies pauca, which is probably native to South or Central America. Xylella fastidiosa causes a variety of diseases.