Emerging Needle Blight Diseases in Atlantic Pinus Ecosystems of Spain

Abstract

Red band needle blight caused by Dothistroma septosporum and D. pini, and brown spot needle blight caused by Lecanosticta acicola provoke severe and premature defoliation in Pinus, and subsequent reduction of photosynthetic surfaces, vitality, and growth in young and adult trees. The recurrent damage results in branch and tree death. Until recently, pine needle blight diseases have had only minor impacts on native and exotic forest trees in the North of Spain, but in the past five years, these pathogen species have spread widely and caused severe defoliation and mortality in exotic and native plantations of Pinus in locations where they were not detected before. In an attempt to understand the main causes of this outbreak and to define the effectiveness of owners' management strategies, four research actions were implemented: a survey of the management activities implemented by the owners to reduce disease impact, the evaluation of specific symptoms and damage associated with infection, and the identification of the causative pathogenic species and their reproductive capacity. Morphological characteristics of the fungus and molecular identification were consistent with those of Lecanosticta acicola and Dothistroma spp., D. septosporum, D. Pini, and both mating types were present for the three identified pathogens. The local silvicultural management performed, mainly pruning and thinning, was not resulting in the expected improvement. The results of this study can be applied to establish guidelines for monitoring and controlling the spread of needle blight pathogens.

Detection of pine needle diseases caused by Dothistroma septosporum, Dothistroma pini and Lecanosticta acicola using different methodologies

“…The opposite was found in Northern Spain, where more than 80% of the diseased plots were infected with L. acicola (de Urbina et al, 2017). The opposite was found in Northern Spain, where more than 80% of the diseased plots were infected with L. acicola (de Urbina et al, 2017).…”

Lecanosticta acicola: A growing threat to expanding global pine forests and plantations

“…Due to the severity of the disease, the pathogen has been afforded an A1 quarantine status in Africa, Argentina, Chile, Uruguay, Bahrain, Kazakhstan, Ukraine and Russia, and A2 quarantine status in Europe (https :// gd.eppo.int/taxon/ SCIRA C/categ oriza tion). However, reports of new outbreaks of the disease in various European countries have increased significantly since 2008 (Adamson et al, 2015(Adamson et al, , 2018Anonymous, 2012;Cleary et al, 2019;Hintsteiner et al, 2012;Jankovský et al, 2009a;Markovskaja et al, 2011;Mullett et al, 2018;Ortíz de Urbina et al, 2017).…”

New country and regional records of the pine needle blight pathogens Lecanosticta acicola, Dothistroma septosporum and Dothistroma pini

“…Reports of Dothistroma have been scarce from Spain and have centred around the moist maritime climate of the north‐west (“Monitoring of Dothistroma needle blight web‐based map,” ). Although both D. pini (Ortíz de Urbina et al., ) and D. septosporum (Barnes et al., ) have each been reported from Spain, in general, the Dothistroma species is unknown (“Monitoring of Dothistroma needle blight web‐based map, ). This study reports Dothistroma from two new autonomous communities in Spain: D. pini from Aragon and D. septosporum from Comunitat Valenciana.…”