Pine wilt : a fatal disease of exotic pines in the Midwest (2000)

"February 2000.""Sustainable urban landscapes.

Effect of particle size, coupling agent and DDGS additions on Paulownia wood polypropylene composites

Studies aimed at improving the tensile, flexural, impact, thermal, and physical characteristics of wood–plastic composites composed of Paulownia wood flour derived from 36-month-old trees blended with polypropylene were conducted. Composites of 25% and 40% w/w of Paulownia wood were produced by twin-screw compounding and injection molding. Composites containing 0–10% by weight of maleated polypropylene were evaluated and an optimum maleated polypropylene concentration determined, i.e., 5%. The particle size distribution of Paulownia wood filler is shown to have an effect on the tensile and flexural properties of the composites. Novel combination composites of dried distiller’s grain with solubles mixed with Paulownia wood (up to 40% w/w) were produced and their properties evaluated. Depending on the composite tested, soaking composites for 872 h alters mechanical properties and causes weight gain

Analysis of the Pythium ultimum transcriptome using Sanger and Pyrosequencing approaches

<p>Abstract</p> <p>Background</p> <p><it>Pythium </it>species are an agriculturally important genus of plant pathogens, yet are not understood well at the molecular, genetic, or genomic level. They are closely related to other oomycete plant pathogens such as <it>Phytophthora </it>species and are ubiquitous in their geographic distribution and host rage. To gain a better understanding of its gene complement, we generated Expressed Sequence Tags (ESTs) from the transcriptome of <it>Pythium ultimum </it>DAOM BR144 (= ATCC 200006 = CBS 805.95) using two high throughput sequencing methods, Sanger-based chain termination sequencing and pyrosequencing-based sequencing-by-synthesis.</p> <p>Results</p> <p>A single half-plate pyrosequencing (454 FLX) run on adapter-ligated cDNA from a normalized cDNA population generated 90,664 reads with an average read length of 190 nucleotides following cleaning and removal of sequences shorter than 100 base pairs. After clustering and assembly, a total of 35,507 unique sequences were generated. In parallel, 9,578 reads were generated from a library constructed from the same normalized cDNA population using dideoxy chain termination Sanger sequencing, which upon clustering and assembly generated 4,689 unique sequences. A hybrid assembly of both Sanger- and pyrosequencing-derived ESTs resulted in 34,495 unique sequences with 1,110 sequences (3.2%) that were solely derived from Sanger sequencing alone. A high degree of similarity was seen between <it>P. ultimum </it>sequences and other sequenced plant pathogenic oomycetes with 91% of the hybrid assembly derived sequences > 500 bp having similarity to sequences from plant pathogenic <it>Phytophthora </it>species. An analysis of Gene Ontology assignments revealed a similar representation of molecular function ontologies in the hybrid assembly in comparison to the predicted proteomes of three <it>Phytophthora </it>species, suggesting a broad representation of the <it>P. ultimum </it>transcriptome was present in the normalized cDNA population. <it>P. ultimum </it>sequences with similarity to oomycete RXLR and Crinkler effectors, Kazal-like and cystatin-like protease inhibitors, and elicitins were identified. Sequences with similarity to thiamine biosynthesis enzymes that are lacking in the genome sequences of three <it>Phytophthora </it>species and one downy mildew were identified and could serve as useful phylogenetic markers. Furthermore, we identified 179 candidate simple sequence repeats that can be used for genotyping strains of <it>P. ultimum</it>.</p> <p>Conclusion</p> <p>Through these two technologies, we were able to generate a robust set (~10 Mb) of transcribed sequences for <it>P. ultimum</it>. We were able to identify known sequences present in oomycetes as well as identify novel sequences. An ample number of candidate polymorphic markers were identified in the dataset providing resources for phylogenetic and diagnostic marker development for this species. On a technical level, in spite of the depth possible with 454 FLX platform, the Sanger and pyro-based sequencing methodologies were complementary as each method generated sequences unique to each platform.</p

Salutaridine and its derivatives as thebaine-equivalents in the synthesis of aporphines

Here we report on the transformation of tetracyclic morphinan salutaridine (1) into 2,3,10,11-tetrasubstituted (R)-aporphines. This method serves as another chemical proof of the previously verified biosynthetic connection with pentacyclic morphinan-6,8- diene-type thebaine. In the presence of nucleophiles, this procedure could lead to pharmacologically interesting new tetrasubstituted aporphinoids. The enantioselective synthesis of 7S-salutaridinol (2) has been also achieved in order to investigate the acid-catalyzed reactions of this natural morphinan

Geosmithia associated with bark beetles and woodborers in the western USA : taxonomic diversity and vector specificity

Fungi in the genus Geosmithia (Ascomycota: Hypocreales) are frequent associates of bark beetles and woodborers that colonize hardwood and coniferous trees. One species, Geosmithia morbida, is an economically damaging invasive species. The authors surveyed the Geosmithia species of California and Colorado, USA, to (i) provide baseline data on taxonomy of Geosmithia and beetle vector specificity across the western USA; (ii) investigate the subcortical beetle fauna for alternative vectors of the invasive G. morbida; and (iii) interpret the community composition of this region within the emerging global biogeography of Geosmithia. Geosmithia was detected in 87% of 126 beetle samples obtained from 39 plant species. Twenty-nine species of Geosmithia were distinguished, of which 13 may be new species. Bark beetles from hardwoods, Cupressus, and Sequoia appear to be regular vectors, with Geosmithia present in all beetle gallery systems examined. Other subcortical insects appear to vector Geosmithia at lower frequencies. Overall, most Geosmithia have a distinct level of vector specificity (mostly high, sometimes low) enabling their separation to generalists and specialists. Plant pathogenic Geosmithia morbida was not found in association with any other beetle besides Pityophthorus juglandis. However, four additional Geosmithia species were found in P. juglandis galleries. When integrated with recent data from other continents, a global pattern of Geosmithia distribution across continents, latitudes, and vectors is emerging: of the 29 Geosmithia species found in the western USA, 12 have not been reported outside of the USA. The most frequently encountered species with the widest global distribution also had the broadest range of beetle vectors. Several Geosmithia spp. with very narrow vector ranges in Europe exhibited the similar degree of specialization in the USA. Such strong canalization in association could reflect an ancient origin of each individual association, or a recent origin and a subsequent diversification in North America.Czech Grant Agency (grant no. 16-15293Y), Long-Term Research Development Project (grant number RVO 67985939), Ministry of Education, Youth and Sports of the Czech Republic (grant number LO1509), USDA NIFA Western Region IPM Center and Critical Issues—Emerging and New Plant and Animal Pests and Diseases grant programs, USDA Forest Service Forest Health Monitoring Program (Detection Monitoring Grant No. INT-DM-09-01 and Evaluation Monitoring Grant No. INT-EM-B-11-03), USDA Forest Service Special Technology Development Grant R4-2011-01 (administered by A. S. Munson).http://www.tandfonline.com/toc/umyc202018-04-24hj2017Forestry and Agricultural Biotechnology Institute (FABI)Microbiology and Plant Patholog

Effect of CO2 Enrichment on Synthesis of Some Primary and Secondary Metabolites in Ginger (Zingiber officinale Roscoe)

The effect of two different CO2 concentrations (400 and 800 μmol mol−1) on the photosynthesis rate, primary and secondary metabolite syntheses and the antioxidant activities of the leaves, stems and rhizomes of two Zingiber officinale varieties (Halia Bentong and Halia Bara) were assessed in an effort to compare and validate the medicinal potential of the subterranean part of the young ginger. High photosynthesis rate (10.05 μmol CO2 m−2s−1 in Halia Bara) and plant biomass (83.4 g in Halia Bentong) were observed at 800 μmol mol−1 CO2. Stomatal conductance decreased and water use efficiency increased with elevated CO2 concentration. Total flavonoids (TF), total phenolics (TP), total soluble carbohydrates (TSC), starch and plant biomass increased significantly (P ≤ 0.05) in all parts of the ginger varieties under elevated CO2 (800 μmol mol−1). The order of the TF and TP increment in the parts of the plant was rhizomes > stems > leaves. More specifically, Halia Bara had a greater increase of TF (2.05 mg/g dry weight) and TP (14.31 mg/g dry weight) compared to Halia Bentong (TF: 1.42 mg/g dry weight; TP: 9.11 mg/g dry weight) in average over the whole plant. Furthermore, plants with the highest rate of photosynthesis had the highest TSC and phenolics content. Significant differences between treatments and species were observed for TF and TP production. Correlation coefficient showed that TSC and TP content are positively correlated in both varieties. The antioxidant activity, as determined by the ferric reducing/antioxidant potential (FRAP) activity, increased in young ginger grown under elevated CO2. The FRAP values for the leaves, rhizomes and stems extracts of both varieties grown under two different CO2 concentrations (400 and 800 μmol mol−1) were significantly lower than those of vitamin C (3107.28 μmol Fe (II)/g) and α-tocopherol (953 μmol Fe (II)/g), but higher than that of BHT (74.31 μmol Fe (II)/g). These results indicate that the plant biomass, primary and secondary metabolite synthesis, and following that, antioxidant activities of Malaysian young ginger varieties can be enhanced through controlled environment (CE) and CO2 enrichment