Isolation of Fungi from Healthy and Blue-Stain Infected Piñon at the Sevilleta LTER

Piñon trees in piñon-juniper woodlands in the Southwest have been showing increase mortality due in part to major droughts that have been impacting this area. However, it is unclear if drought-induced morality is the sole cause. Under stress conditions, piñon trees are commonly attack by bark beetles (Ips confusus) and blue-stain fungi (Ophiostoma sp.). We described wood-associated fungal communities isolated from cores of healthy and bark-beetle damage trees. Samples were taken from healthy and dying piñon from experimental plots in a piñon-juniper woodland at the LTER site in the Sevilleta National Wildlife Refuge, NM. The experiment utilizes different treatments: excluding 50% of ambient precipitation, 150% mean annual precipitation, exclusion control and environmental controls. Cores were taken from trees, surface sterilize,  cut into 1-2 cm sections and plated on PDA (potato dextrose agar) with antibiotics. Isolates were sequenced using the ITS rDNA barcode region. An approximate total of 155 unique sequences were obtained. The wood endophytic communities were dominated by Pleosporales, Dothidiales and Xylariales. Common genera include Penicillium, Hormonema and Pestalotiopsis. Fungi within the genus Ophiostoma were also recovered from bark-bettle damage trees. This initial characterization of wood-isolated fungi will help document potential dormant pathogens and changes in community with the arrival of blue-stain fungi due to insect attack.