<I>Matsucoccus macrocicatrices</I> (Hemiptera: Matsucoccidae): First Report, Distribution, and Association With Symptomatic Eastern White Pine in the Southeastern United States

Abstract

We provide the first report of Matsucoccus macrocicatrices Richards (Hemiptera: Matsucoccidae) feeding and reproducing on eastern white pine, Pinus strobus L., in the southeastern United States. Until now, M. macrocicatrices had been reported only from the Canadian Atlantic Maritimes, New Hampshire, and Massachusetts. Entomological holdings of 27 major museums in eastern North America have no historical records for M. macrocicatrices from the southeastern region. However, our field surveys and molecular analyses (DNA barcoding) have resulted in the collection and positive identification of M. macrocicatrices in Georgia, North Carolina, South Carolina, Tennessee, Virginia, and West Virginia In addition to the new geographic range, M. macrocicatrices is also being associated with dieback and mortality of all diameter classes of P. strobus leading to concern about a potential shift from its historically nonpestiferous presence on the host tree. On P. strobus, M. macrocicatrices was found embedded in cankers or present on top of the bark with necrotic tissue under their feeding area, indicating that they may be creating wounds for opportunistic pathogenic fungi to infest. Further, we found M. macrocicatrices living outside of the epiphytic mats of its symbiotic fungus, Septobasidium pinicola Snell. This study shows that M. macrocicatrices is now widespread in the southeastern United States, with implications for the future survival and regeneration of P. strobus in eastern North America.

Soil and Stocking Effects on Caliciopsis Canker of Pinus strobus L.

“…Wingf.) have been associated with white pine cankers [6,7]. The pathogenicity of C. pinea to eastern white pine was demonstrated by Ray in 1936 [8].…”

Dendrochronological Analyses and Whole-Tree Dissections Reveal Caliciopsis Canker (Caliciopsis pinea) Damage Associated with the Declining Growth and Climatic Stressors of Eastern White Pine (Pinus strobus)

“…Once disseminated, it has been hypothesized that C. pinea spores require a "port of entry in order to penetrate the host tissue" [26]. Previous studies suggest entry can occur through natural and artificial wounds, natural bark cracks, insect feeding sites, foliar scars, and lenticels [23,26,[28][29][30]. Once infected, host symptoms include excessive resin production, crown thinning, roughened bark, sunken brown/red depressed lesions, bark fissures/cracks, necrotic tissue, and reduced wood quality ( Figure 1A-F) [24,25,[30][31][32].…”

“…Previous studies suggest entry can occur through natural and artificial wounds, natural bark cracks, insect feeding sites, foliar scars, and lenticels [23,26,[28][29][30]. Once infected, host symptoms include excessive resin production, crown thinning, roughened bark, sunken brown/red depressed lesions, bark fissures/cracks, necrotic tissue, and reduced wood quality ( Figure 1A-F) [24,25,[30][31][32]. Ascocarps may also be present on roughened bark or at branch axils, with long black stromata that resemble eyelash clusters [9,24,25].…”

“…Reports of canker occurrence and associated white pine damage have been increasing, particularly in eastern North America [24,28,[33][34][35][36]. Caliciopsis-related damage was reported in 1997 in the northeastern U.S. [28], by 2003 in Québec, Canada [37], and in 2006 in the southeastern and midwestern U.S. [30,35]. Some of the most severe damage occurs in pole-sized white pine stands, with more than 70% of sites in New Hampshire being symptomatic [28], as well as pockets of tree mortality in the midwestern, southeastern, and northeastern U.S. [24,28,30,33,34].…”

“…Caliciopsis-related damage was reported in 1997 in the northeastern U.S. [28], by 2003 in Québec, Canada [37], and in 2006 in the southeastern and midwestern U.S. [30,35]. Some of the most severe damage occurs in pole-sized white pine stands, with more than 70% of sites in New Hampshire being symptomatic [28], as well as pockets of tree mortality in the midwestern, southeastern, and northeastern U.S. [24,28,30,33,34]. To monitor and evaluate Caliciopsis canker severity, the U.S. Forest Service recently developed an assessment protocol that recommends dividing white pine tree stems into thirds and counting the number of Caliciopsis canker-associated resin streaks per third [24].…”