FIRST REPORTING OF CRYPTOSPORIOPSIS TARRACONENSIS, AGENT FOR DEATHING THE GEMS IN HAZELNUTS OF THE HIGH LAZIO https://phydia.eu/

DEFENCE: During the three-year period 2018-2020, an accurate phytopathological monitoring was carried out on the hazelnut groves of the Viterbo area, belonging to ten companies, a project born from the collaboration between the Terremerse cooperative company, the university spin-off Phy.Dia. and the Department of Agricultural and Forestry Sciences (DAFNE) of the University of Tuscia.One of the most interesting results resulting from the carrying out of the sampling activities and consequent laboratory analyzes was the discovery of the fungus Cryptosporiopsis tarraconensis, causal agent of the Desiccation of the Buds, which was recognized both morphologically and by sequencing the ITS stretch of DNA. This microorganism was found in 3 of the 10 farms subject to monitoring, for a total of about 30% of the 25,000 plants examined, mainly belonging to the Nocchione variety; the symptoms were less evident on Tonda Gentile Romana and Giffoni. ? ? Leaf necrosis (left) and branch desiccation (right) induced by C. tarraconensis. Author: Phy.Dia. srl C. tarraconensisit was reported for the first time in Spain in the Tarragona region, from which it takes its name, in 1990 as an agent of the "bud rot" or "borró sec" on hazelnut, whose main symptomatology is precisely the drying of the branches younger and the buds associated with them, a problem that in that area is estimated to have led to an approximate 30-40% drop in production; more recently, the same pathogen has been identified as a cause of leaf spot on the same host plant in Iran. As regards the Italian situation, C. tarraconensis is never officially reported on the national territory and in general there is a lack of studies and data concerning the biology, the real diffusion and the means of defense against this pathogen.

Source: Tagliavento V., de Santis F., Ciarroni S., Balestra GM, Cristofori V., Pradolesi G. - First report of bud rot caused by Cryptosporiopsis tarraconensis on Corylus avellana in Italy. J. Plant Pathol. (2020). https://doi.org/10.1007/s42161-020-00680-6 Published 08-01-2020