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ABSTRACTRhizopogonspecies are ecologically significant ectomycorrhizal fungi in conifer ecosystems. The importance of this system merits the development and utilization of a more robust set of molecular markers specifically designed to evaluate their evolutionary ecology. Anonymous nuclear loci (ANL) were developed for R. subgenus Amylopogon. Members of this subgenus occur throughout the United States and are exclusive fungal symbionts associated with Pterospora andromedea, a threatened mycoheterotrophic plant endemic to disjunct eastern and western regions of North America. Candidate ANL were developed from 454 shotgun pyrosequencing and assessed for positive amplification across targeted species, sequencing success, and recovery of phylogenetically informative sites. Ten ANL were successfully developed and were subsequently used to sequence representative taxa, herbaria holotype and paratype specimens in R. subgenus Amylopogon. Phylogenetic reconstructions were performed on individual and concatenated data sets by Bayesian inference and maximum likelihood methods. Phylogenetic analyses of these 10 ANL were compared with a phylogeny traditionally constructed using the universal fungal barcode nuc rDNA ITS1-5.8S-ITS2 region (ITS). The resulting ANL phylogeny was consistent with most of the species designations delineated by ITS. However, the ANL phylogeny provided much greater phylogenetic resolution, yielding new evidence for cryptic species within previously defined species of R. subgenus Amylopogon. Additionally, the rooted ANL phylogeny provided an alternate topology to the ITS phylogeny, which inferred a novel set of evolutionary relationships not identified in prior phylogenetic studies.

This study was a preliminary analysis of the genetic structure of the ectomycorrhizal species Russula discopus, R. pseudocarmecinaand R. ochraceorivulosawith disjunct distributions in continental Africa and Madagascar. Phylogenetic analyses of the nuclear ITS1/5.8S/ITS2 region and the mitochondrial atp6 gene were performed with specimens from both locations for each species along with a suitable outgroup for each of the three taxa. Additional analyses of the ITS1/5.8S/ITS2 region using the African and Malagasy specimens and additional taxa in the genus Russulaalso were performed. R. pseudocarmecinaand R. discopusboth exhibited genetic structure as shown by a relatively high percentage difference in ITS and atp6 sequences, high bootstrap support for African or Malagasy groups and the presence of indels in the ITS sequence that are unique to either Africa or Madagascar. African and Malagasy groups of each species were more closely related to each other than to other taxa in Russula. Genetic structure also existed in populations of R. ochraceorivulosa, but bootstrap support was weaker than in the other two species. In addition, there was less sequence divergence in R. ochraceorivulosaand this species was the only one for which the same atp6 haplotype was found in both Africa and Madagascar. Reciprocal monophyly for all three species was consistent with the hypothesis that the same vicariance event may be responsible for the genetic structure observed here, although shorter branch lengths, lower bootstrap support and the presence of the same atp6 haplotype in Africa and Madagascar for R. ochraceorivulosasuggested slower evolutionary rates or geographical isolation after the other two taxa. In addition to the geological events that separated Africa and Madagascar, environmental changes during the Miocene or later might have had an effect on the distribution of these species.

Elaphomyces compleximurussp. nov. and E. digitatussp. nov. are described from the Pakaraima Mountains of Guyana. Macromorphological, micromorphological, habitat and DNA sequence data are provided for each new species. This is the first report of Elaphomycesascomata associated with ectomycorrhizal members of the Fabaceae and also for the genus from the lowland South American tropics.

A phylogenetic analysis of Lactariussect. Deliciosiwas performed based on collections of all known species. Several samples of each species were included, originating from a wide geographic range. The two DNA regions we used (ITS and a part of the gene encoding glyceraldehyde-3-phosphate dehydrogenase) showed an incongruent phylogenetic signal. Much attention was paid to carefully observed macro-and micromorphological characters to draw taxonomic conclusions. We currently accept 38 taxa (31 species and seven varieties) in Lactariussect. Deliciosiworldwide; four species are new to science. More sampling is needed to resolve the status of the North American varieties. Our knowledge of the Asian species in this section remains fragmentary. The monophyly of the section and its position within Lactariussubgenus Piperites, as proposed in recent morphology-based classification schemes, is confirmed. The intrasectional relationships however do not coincide with the color of the latex (as previously supposed). Intercontinental conspecificity is low in general. The name L. deliciosusis wrongfully applied in North and Central America and only two species seem to occur in both Asia and Europe.

This study documents the changes in nutrient fluxes associated with internal tidal bores arriving on Florida Keys coral reefs and points to biological use of subthermocline nitrate brought onshore by this mechanism. Internal bores on Conch Reef, Florida Keys, are associated with concentrations of 1.0–4.0 µmol L−1nitrate (NO3−) and 0.1–0.3 µmol L−1soluble reactive phosphate (SRP) and onshore flow velocities of 0.1–0.3 m s−1. The arrival of internal bores causes 10–40 fold increases in nutrient concentrations and 1–2 orders of magnitude increases in nutrient flux relative to ambient, nonbore conditions. The magnitude and duration of cool‐water nutrient transport events increases significantly with increasing depth on reef slopes. In June 2001, the gradient of increased exposure to subsurface water with depth corresponded to increased percentage of N and δ15N and decreased C:N ratio in a common benthic macroalga, Codium isthmocladum. Internal tidal bores are widespread throughout the Florida Keys reef tract, with cool‐water episodes influencing reefs up to 10%–25% of the time during summer months and with significant variability among years. Estimated inputs of nitrogen and phosphorus by internal tidal bores to Florida Keys reef slopes are as much as 40‐fold larger than published estimates of inputs to near‐shore waters from waste water and storm water runoff. Internal tidal upwelling represents an important, previously underestimated, episodic source of nutrients on the Florida Keys reef tract. In order to assess nutrient availability in this system accurately it is essential to understand natural sources of high‐frequency variability.

Morphological and habitat descriptions, illustrations and taxonomic discussions are presented for two newly described species of pleurotoid Lactarius, L. brunellusand L. multiceps, from the Pakaraima Mountains of Guyana. A third species, L. igapoensis, is synonymized with L. panuoides.

Species in the large mushroom genus Russula are important ecologically as ectomycorrhizal fungi and economically as comestibles. Most infrageneric classification schemes of this genus have originated in Europe, but because of nomenclatural history and an evolving suite of characters these systems remain largely incongruent. Using ribosomal DNA sequences for 87 species representing all infrageneric taxa described from Europe, the phylogenetic position and relationships among these species were examined. Cladistic analysis of the ITS1, 5·8S, and ITS2 regions showed a cluster of five to six small to large clades basal in the topology and one large apical clade arising from the deeper nodes, none of which has been previously recognized in toto at the subgeneric level. Two of these groups, the Compactae and Pallidosporinae, which have been previously recognized as subsections of section Compacta, did not appear to be closely related. Bootstrap support and Bremer decay values indicated that collapse of the tree into monophyly at the deeper nodes would result in two large groups which are consistent with the classical subgeneric concept of the Eurussulae and a narrowed Compactae. The topology confirmed some previously described infrageneric taxa at the section level including the Tenellae and Heterophyllae and at the subsection level including the Cupreinae, Laricinae, Lilaceinae, Integroidinae, Violaceinae, Sphagnophilinae, Viridantinae, Emeticinae, Subvelatae, Pallidosporinae, and portions of the Polychromae and Sardoninae. The molecular analysis also indicated many interesting new combinations or relationships not previously conceived. Mapping of characters such as spore print colour, taste, and presence of acid resistant incrustations, which have been used to define infrageneric taxa in Russula, onto the phylogeny identified interesting patterns consistent with hypotheses regarding plesiomorphic and apomorphic characters. However, because of potential loss or reversal of character states, this analysis did not support their unequivocal use in infrageneric classification.

Pseudotulostoma volvatagen. sp. nov. is described from the south-central Pakaraima Mountains of Guyana. Pseudotulostoma volvatais associated with ectomycorrhizal Dicymbe corymbosatrees (Caesalpiniaceae) and placed in the Ascomycota, Eurotiales, Elaphomycetaceae. Included are a description of the genus and species, illustrations of the macroscopic and microscopic features, and a discussion of the distinctive features and phylogenetic placement of this fungus.

Pseudotulostoma volvata gen. sp. nov. is described from the south-central Pakaraima Mountains of Guyana. Pseudotulostoma volvata is associated with ectomycorrhizal Dicymbe corymbosa trees (Caesalpiniaceae) and placed in the Ascomycota, Eurotiales, Elaphomycetaceae. Included are a description of the genus and species, illustrations of the macroscopic and microscopic features, and a discussion of the distinctive features and phylogenetic placement of this fungus.

AbstractThe Russulales consists of agaricoid, gasteroid and hypogeous gasteroid taxa of basidiomycetes closely related to Russulaand Lactarius.Because there have been no molecular phylogenetic studies of the Russulales, attempts at formulating a natural classification for these taxa have met with difficulty. In this study, nuclear large subunit rDNA (n-LSU) was used to infer phylogenetic relationships among members of the Russulales including agaricoid, tropical pleurotoid and annulate taxa, and gasteroid and hypogeous gasteroid genera. Analysis of the n-LSU region indicated that Russulasensu strictu (excluding gasteroid and hypogeous gasteroid taxa) can be considered polyphyletic with two well supported groups, one group arising separately from the main body of the tree and one group basal to Lactarius. Russulasensu lato can be considered paraphyletic with gasteroid and hypogeous gasteroid forms nested in the same clades alongside agaricoid taxa. Lactariussensu lato was found to be a monophyletic group that includes agaricoid, gasteroid and hypogeous gasteroid taxa. Gasteroid and hypogeous gasteroid genera were scattered throughout the order, with Macowanites, Gymnomyces, Cystangiumand Martellianested within Russula, while Zelleromycesand Arcangeliellagrouped within Lactarius.Most of the gasteroid and hypogeous gasteroid genera appear to be polyphyletic and their position was supported within established infrageneric taxa of Russulaand Lactarius.These results suggested that synonomy of gasteroid genera into Russulaand Lactariusis justifiable.

AbstractThree species of pleurotoid, putatively lignicolous basidiomycetes previously described in the genus Lactariussect Panuoideiwereredescribed from fresh material collected in Guyana and Japan. In Guyana, Lactarius panuoidesand Lactarius campinensiswere restricted to forests dominated by ectomycorrhizal Dicymbespecies (Caesalpiniaceae) and basidiomata of both pleurotoid species were subtended by ectomycorrhizal rootlets. This suggested an ectomycorrhizal nutritional mode for these fungi. Analysis of DNA sequences in the nuclear large subunit region taken from basidiomata and co-occurring ectomycorrhizae of L. panuoidesand L. campinensisconfirmed that these fungi are ectomycorrhizal and that their fruiting habit on organic deposits and well rotted wood at elevated positions is not due to saprotrophy, as previously assumed. Lactarius uyedaewas collected in Japan from mature temperate forests dominated by Fagaceae, yet ectomycorrhizal rootlets were not found in association with the basidiomata. Morphological features and analysis of DNA sequences suggested that L. panuoidesand L. uyedaehave affinities with established sections of the genus Lactarius, regardless of the pleurotoid morphology of their basidiomata, and that L. campinensisshould be transferred to the genus Russula.Discussion is provided for the genus Pleurogala, which was erected to accomodate putatively lignicolous, pleurotoid species of Lactarius.

Ponderosa pine seedlings were inoculated with Hebeloma crustuliniforme either in growth pouches before they were transplanted to root-mycocosms (P seedlings), or at the time of transfer to root-mycocosms (V seedlings). Uninoculated seedlings served as controls (U seedlings). The use of root-mycocosms allowed examination of portions of hyphae separate from roots and rooting substrate but still in symbiosis with the host. The results thus provided a quantitative basis for estimating hyphal mass and carbon allocation to extramatrical hyphae. The amount of 14CO2 fixed after a 2-h exposure was greatest for P seedlings and least for uninoculated seedlings. Four and nine days after exposure, 14C content was greatest in uninoculated seedlings and least in inoculated seedlings. In isotope distribution and dry mass accumulation, V seedlings were more similar to U than to P seedlings. Calculated on a dry weight basis, the allocation of isotope to mycelium suggested that extramatrical hyphae of P seedlings were a stronger sink for carbon than extramatrical hyphae of V seedlings. Differences in inoculation methods resulted in differences in carbon allocation and physiology of extramatrical hyphae that could affect seedling establishment and survival. Seedlings inoculated by one method cannot serve as surrogates for mycorrhizal seedlings produced by other inoculation techniques.

Neural processes associated with two aspects of visual-spatial attention were investigated with event-related potential (ERPs): those that direct spatial attention to a given point in space and those that modulate the processing of sensory input after attention has been directed. The subjects were 6- to 9-year-old children (51 boys and 35 girls). An arrow cue directed attention from the central to peripheral visual field; targets were then flashed in the attended or ignored visual field 600 msec after the cue.

Internal tidal bores generated by breaking internal waves cause dramatic, high‐frequency variation in temperature, salinity, water velocities, and concentration of chlorophyll aon Conch Reef, Florida Keys. The arrival of bores on the reef slope is linked to a semidiurnal internal tide and is marked by temperature drops of up to 5.4°C and salinity increases of up to 0.6‰ in 1–20 min. These changes are accompanied by the sudden onset of upslope flow 1–15 m above the bottom with speeds of 10–30 cm s−1. Cool, high‐salinity water is transported from below the thermocline seaward of the reef and is resident on the reef slope for up to 4 h before it mixes with surface waters and recedes downslope. Compared with ambient surface water, this deep water can contain significantly elevated concentrations of dissolved nitrate. Physical variability produced by this mechanism increases significantly with depth on the reef slope. Analysis of 3‐yr temperature records indicates the arrival of internal bores is a consistent feature at this site from May through November, with peak activity in July–September. Pulsed delivery of subthermocline water appears to significantly affect the temperature, nutrient, and particle flux regimes on this coral reef.

The potential for mycorrhizal formation and Frankia nodulation were studied in soils from six sites in the Pacific Northwest. The sites included young and old alder stands, a 1-year-old conifer clear-cut, a young conifer plantation, and rotation-aged and old-growth conifer stands. A bioassay procedure was used with both red alder and Douglas fir seedlings as hosts. After 6 weeks growth, seedlings of both hosts were harvested every 3 weeks for 21 weeks and numbers of nodules and ectomycorrhizal types estimated. Nodules formed on red alder and ectomycorrhizae formed on both alder and Douglas fir in soil from all sites. Nodulation potential was highest in soil from the alder stands and the conifer plantation. Seven morphologically distinct ectomycorrhizal types were recovered on Douglas fir and five on alder. Only Thelephora terrestris, a broad-host-range mycobiont, formed mycorrhizae on both hosts. New ectomycorrhizal types formed on both hosts throughout the bioassay. Ectomycorrhizal colonization of alder was greatest in the alder and clear-cut soils. Low ectomycorrhizal colonization on alder was found in soils from sites where conifers were actively growing. Ectomycorrhizal colonization of Douglas fir was highest in the young alder and conifer plantation soils and was low in the rotation-aged conifer soil. The highest diversity of ectomycorrhizal types was found on alder in the conifer clear-cut soil and on Douglas fir in the rotation-aged conifer soil. Effects of host specificity, nodulation and mycorrhiza-forming potential and nodule-mycorrhiza interactions on seedling establishment are discussed in relation to seral stage dynamics and attributes of pioneer ectomycorrhizal fungal species.

Focuses on the challenges that confronted U.S. artillerymen in conducting the first democratic elections in Iraq following the establishment of the Coalition Provisional Authority. Process of conducting the elections; Lack of guidance on the Iraqi government structure; Standardization of elections in the country.