PineEnemy - Exploring the NEmatode-MYcobiota interactions in Pine Wilt Disease

Abstract

Pine wilt disease (PWD) is one of the most important threats to conifer forests in Europe [1] and worldwide [2], causing severe economic and environmental damages. This complex disease results from the interaction between three biological elements: the pathogenic agent Bursaphelenchus xylophilus, also known as pinewood nematode (PWN); the insect-vector (cerambycid beetles of the genus Monochamus) [3], and the host tree, mostly from Pinus spp. [4]. In 1999, B. xylophilus was firstly identified in maritime pines (Pinus pinaster) in Portugal and in Europe [1, 5]. Despite a nationwide monitoring system, enforcement of strict phytosanitary measures and constraints implemented after PWN detection, this devastating problem has spread quickly in Portuguese mainland, Madeira Island [5] and Northern Spain [6]. As a migratory endoparasite, once inside susceptible tree, PWN has the ability to feed on the living parenchyma of the epithelial cells in the resin canals, causing a reduction in water flux and ultimately cessation of resin flow. In the later stages of the disease, PWN assumes a mycetophagous phase. The development of the PWN population appears to be strongly associated with fungi that colonize the declining trees [3]. Fungi harboured in weakened pines are seen as essential for the ongoing development and completion of the PWN life-cycle, affecting not only PWN reproduction [8] but also the number of individuals carried by the insect-vector [9-10]. Through a spatio-temporal analysis, PineEnemy will focus on the characterization of the structure and dynamics of the nematode-fungi interactions through culturable and non-culturable approaches with special emphasis in metagenomics analysis. Our aim is to understand if PWN-associated mycobiota plays a key-role in the development of PWD, in interaction with PWN and insect-vector, and into which extend can be targeted to disrupt the disease cycle.