Phytoplasma diseases in Azerbaijan: An historical perspective

The review devotes to research on phytoplasma diseases in fruit trees and vegetables in Azerbaijan since 2003. In the frame of different projects, many surveys were undertaken and revealed various phytoplasmas that were identified and molecularly characterized. The use of molecular tools allowed to demonstrate that the Azerbaijanian phytoplasma strains were sometimes closely related if not identical to other strains detected in the Euro-Mediterranean basin. In the particular cases of ‘Candidatus Phytoplasma pyri’ and ‘Ca. P. prunorum’ strains with inter-species recombination were evidenced. Regarding the ‘Ca. P. solani’ strains associated to grapevine “bois noir” cases in Absheron peninsula and Gabala, new and previous genotyping tests highlighted the high diversity of this phytoplasma in Azerbaïjan. Upon collections of Cixidae planthoppers conducted in northern Azerbaijan, Hyalesthes obsoletus and Reptalus noahi were shown to harbor two ‘Ca. P. solani’ new genotypes phylogenetically distant from known genetic clusters.