Erwinia chrysanthemi causes sudden decline of date palm in Saudi Arabia
In Saudi Arabia, since spring 1995, a new and serious disease of date palm (Phoenix dactylifera) has been observed in the Al Qassim region (Central Saudi Arabia). The disease, called ‘sudden decline’, starts with the appearance of a wilted young spear (unopened leaf) which is rapidly followed (within 2 weeks) by the death of the whole tree. Within one more week, suckers are also killed. Usually, the disease attacks only a few trees in an orchard and especially affects young plantations (3-7 year old trees). On diseased trees, massive amounts of slime are observed in the heart and a bacterium could be isolated. Biological and physiological tests of the isolated bacterium suggested that it is a form of Erwinia chrysanthemi (EPPO A2 quarantine pest). The pathogenicity of the isolated bacterium was confirmed by artificial inoculation to date palm seedlings. The EPPO Secretariat had previously no data on the occurrence of E. chrysanthemi in Saudi Arabia, nor on its pathogenicity to date palm.
Sources
Abdalla, M.Y. (2001) Sudden decline of date palm trees caused by Erwinia chrysanthemi.
Plant Disease, 85(1), 24-26.