Isolated finding of Citrus tristeza closterovirus in Algeria
The EPPO Secretariat has recently been informed by the NPPO of Algeria that an isolated focus of Citrus tristeza closterovirus (EPPO A2 quarantine pests) was found on two experimental plots of citrus propagation material. These plots were located at the experimental stations of Béni Tamou and Chébli (Wilaya of Blida). Until this finding, CTV had never been found at these two locations. Phytosanitary measures have immediately been taken: movement of citrus material from infected areas was prohibited and further tests (DAS-ELISA, immunoprinting, indexing) were done to delimit the extent of the infection. Samples were taken from 4869 trees and 4000 nursery plants grown at Béni Tamou and Chébli. CTV was not detected in the 4000 nursery plants tested. On trees used for the production of basic material, 4 trees out of 996 tested gave positive results (0.4%). On trees used for the production of pre-basic material, 18 trees out of the 580 tested gave positive results (3.1%). At Chébli, 70 positive trees were found out of the 3289 tested (2.1%). All 92 infected trees were destroyed. Surveys are continuing to verify the absence of the virus.
The situation of Citrus tristeza closterovirus in Algeria can be described as follows: Present, found only in 2 citrus multiplication plots at the experimental stations of Béni Tamou and Chébli (Wilaya of Blida), under eradication.
NPPO of Algeria, 2003-05.