Xylella in Apulia: review finds no evidence of multiple types

The opinion from EFSA’s Panel on Plant Health is the last of three outputs addressing a number of questions from the European Commission on X. fastidiosa in Apulia. In this one the Panel addresses the question of whether different types of X. fastidiosa exist in Apulia, where a disease outbreak An excess of disease cases compared to what would be normally expected in a population. An outbreak may occur in a restricted geographical area, or may extend over several countries. It may last for a few days or weeks, or for several years. is affecting olive trees and other plants.

A single study raised the possibility that multiple genetic types of X. fastidiosa are present in the area. However, EFSA’s plant health specialists say there is currently no evidence to support this hypothesis.

To reach its conclusion, the Panel reviewed the latest scientific literature and analysed DNA A complex chain-like molecule that carries the genetic material, present in living organisms and some viruses. DNA (deoxyribonucleic acid) is capable of copying itself and carries the instructions for all the proteins used to create and sustain life. sequencing data retrieved from samples collected in Apulia. All the papers concluded that DNA samples collected from olive trees and other plants belong to the same sequence type, called “ST53”.

For the sequence data analysis, the Panel used a dedicated database established in 2005 that contains the DNA sequences of nearly 300 X. fastidiosa samples. The Panel highlights that further studies with larger sample sizes are needed to provide more comprehensive answers on this issue. These should include an analysis of complete X. fastidiosa  genome The entire amount of genetic material found in the cells of living organisms. sequencing.

• Statement on diversity of Xylella fastidiosa subsp. pauca in Apulia