Variation in virulence among four root-inhabiting Ophiostomatoid fungi on Pinus taeda L., P. palustris Mill, and P. elliottii Engelm. seedlings

Ophiostomatoid fungi have been implicated in root disease of pines in the southeastern United States. To understand more about their virulence, inoculation studies were conducted on loblolly (Pinus taeda), longleaf (Pinus palustris), and slash pine (Pinus elliotii). One-year-old bareroot seedlings, after being planted and established for 11 weeks, were wound-inoculated with one of four prominent North American ophiostomatoid fungal species. After three months, a darkened lesion, extending from the point of inoculation was observed for all species. Grosmannia huntii (L. huntii) caused the greatest lesion and occlusion length in loblolly pine and slash pine. Leptographium procerum and L. terebrantis caused similar lesion and occlusion lengths and were the least virulent among the fungi tested. These studies indicate clear virulence differences among the four North American fungi. Grosmannia huntii, previously not known to be pathogenic, was observed causing significant damage compared with other well-known Leptographium species. Finally, lesion and tissue occlusion lengths were significantly smaller in longleaf pine for all fungal species when compared to loblolly and slash pine

Virulence of Leptographium serpenson longleaf pine seedlings under varying soil moisture regimes

Recently, Leptographium serpens has been recovered from the roots of declining and dead longleaf pine (Pinus palustris) in stands associated with various abiotic stresses. Although most data suggest that L. serpens is pathogenic to various Pinus spp., there is little known of its virulence on longleaf pine or its relationship with abiotic stress in causing disease. These trials examined the effects of L. serpens infection coupled with drought stress. Trials began with wound inoculations of bareroot longleaf pine seedlings in spring 2006 and 2007 at the seedling stress facility at Auburn University. Soon after inoculation, seedlings were also subjected to adequate moisture, moderate drought, or severe drought. Sixteen weeks after inoculation, longleaf pine survival, L. serpens virulence, and seedling growth characteristics were measured. Longleaf pine seedlings inoculated with L. serpens had 33% mortality (138/420) which was significantly greater than nonwounded control seedlings (22%, 47/211). Survival and lesion size on longleaf pine suggests that L. serpens is moderately pathogenic to longleaf pine seedlings. Separately, moisture stress associated with low soil moisture also contributed to seedling mortality. Results suggest that L. serpens infection and moisture stress commonly experienced by southern pines act independently to stress longleaf pine

Susceptibility of longleaf pine roots to infection and damage by four root-inhabiting ophiostomatoid fungi

Restoration of longleaf pine-dominated uplands is common on many public and private lands throughout the southeastern United States. The once dominant longleaf pine ecosystem is important to many now-threatened and endangered plant and animal species, and land managers are increasing efforts to reestablish this fire-dependent forest. Unfortunately, tree mortality in longleaf pine has been observed following attempts to re-introduce prescribed fire. Root-inhabiting ophiostomatoid fungi and their insect vectors have invaded roots of symptomatic longleaf pine. Although, the relationship between ophiostomatoid fungi and longleaf pine roots is poorly understood. In order to assess the pathogenicity and virulence of four ophiostomatoid fungi to longleaf pine, trees within two broad age classes (20-30 and 40-60 years) were used for root inoculations during the fall of 2006 and 2007 along with the spring of 2007 and 2008. All fungal species consistently caused resin-filled, discolored lesions on the phloem surface extending to the xylem. The successful inoculation of healthy longleaf pine roots confirms the pathogenicity of Grosmannia huntii, Leptographium procerum, Leptographium serpens, and Leptographium terebrantis. G. huntii caused the largest lesions, including 22.20cm2, 13.37cm2, and 9.21cm2 larger than L. procerum, L. terebrantis, and L. serpens respectively. In contrast, L. procerum caused significantly smaller lesions than all other fungi, including 8.65cm2 smaller than L. terebrantis and 10.69cm2 smaller than L. serpens. Restoration efforts of longleaf pine may be affected by fungal root infection in the future. Future studies should focus on the interactions between stress factors associated with longleaf pine to define more clearly the ecological role of root-inhabiting ophiostomatoid fungi in the ecosystem

Root lesions in large loblolly pine (Pinus taeda L.) following inoculation with four root-inhabiting ophiostomatoid fungi

Loblolly pine decline, characterized by deteriorating root systems leading to shortening and thinning of foliage, has been observed throughout portions of the south-eastern United States. Several root-inhabiting ophiostomatoid fungi, including Leptographium procerum, Leptographium terebrantis, Leptographium serpens, and Grosmannia huntii are associated with lateral root damage on declining loblolly pine. Trees of various ages were inoculated in primary lateral roots during fall (2006 and 2007) and spring (2007 and 2008). All fungi caused a darkened, resin-filled lesion on the surface of the phloem, extending into the xylem that was larger than that of controls. Only lesions associated with G.similar to huntii infection were significantly larger in the spring season, compared with the fall. Grosmannia huntii was found to be the most virulent fungus, causing lesions that were longer, deeper and larger than all other fungal species during the spring and larger than L.similar to terebrantis and L.similar to procerum in the fall. Leptographium serpens was the second most virulent fungal species, causing lesions larger than L.similar to procerum and L.similar to terebrantis (with the exception of lesion depth) during both seasons. These tests indicate that G.similar to huntii and L.similar to serpens are significant root pathogens, capable of causing considerable damage, while L.similar to terebrantis and L.similar to procerum may be less virulent. Depending on the actions of their vectors, G.similar to huntii and L.similar to serpens may be responsible for significant root deterioration and tree disease

Prescribing practices in German and Swiss psychiatric university and in non-university hospitals : national differences

OBJECTIVE: There are great variations between hospitals in the way drugs are prescribed, and these variations may be due to multiple factors such as local prescribing traditions, pharmacoeconomic considerations, drug availability, regional differences of population, disease prevalence etc. Available studies on prescribing habits, apart from studies performed in a unique center, have until now been mainly restricted to single countries or regions and the comparisons across countries or regions have often been limited by the use of diverse methodologies and definitions. The aim of the present study was to compare drug prescriptions between German and Swiss psychiatric services with regard to their preference of newer psychotropics. MATERIAL AND METHODS: Five psychiatric hospitals, associated to the AMSP project, were chosen to represent Swiss and German clinics, university and non-university settings. Data were available from one index day on 572 patients and 1,745 prescriptions. The comparisons were adjusted for age and gender. RESULTS: There was a significant difference (p < 0.001) with regard to the prescription of newer antidepressants (NAD), Swiss clinicians giving proportionally more (65.2%) than the German psychiatrists (48.3%). No significant difference was, on the other hand, found as to the proportion of atypical antipsychotics, the lack of difference being due to the higher proportion of clozapine among the atypical antipsychotics in Germany. CONCLUSION: There seems, therefore, to be a higher propensity for Swiss hospital psychiatrists to prescribe newer antidepressants. This seems to be due to national or regional prescribing traditions. Further studies are needed to investigate the economical influences on antidepressant prescribing in Swiss and German clinics