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Emergence of insect-transmitted plant viruses over the past 10–20 years has been disproportionately driven by two so-called supervectors: the whitefly, Bemisia tabaci, and the Western flower thrips, Frankliniella occidentalis. High rates of reproduction and dispersal, extreme polyphagy, and development of insecticide resistance, together with human activities, have made these insects global pests. These supervectors transmit a diversity of plant viruses by different mechanisms and mediate virus emergence through local evolution, host shifts, mixed infections, and global spread. Associated virus evolution involves reassortment, recombination, and component capture. Emergence of B. tabaci–transmitted geminiviruses (begomoviruses), ipomoviruses, and torradoviruses has led to global disease outbreaks as well as multiple paradigm shifts. Similarly, F. occidentalis has mediated tospovirus host shifts and global dissemination and the emergence of pollen-transmitted ilarviruses. The plant virus–supervector interaction offers exciting opportunities for basic research and global implementation of generalized disease management strategies to reduce economic and environmental impacts.

Halo blight, caused by Pseudomonas syringaepv. phaseolicola(Burkholder) (Psp), is a seed‐borne bacterial disease of common bean (Phaseolus vulgarisL.) that is found worldwide, particularly in temperate climates, such as in the midwestern United States. Under favorable conditions, halo blight has been reported to cause up to 45% losses on susceptible cultivars. Nine Pspraces have been identified on the basis of the interaction with a series of differentials possessing different combinations of resistance (R) genes. To date, high levels of resistance have been identified for all Pspraces with the exception of race 6, which is becoming more prevalent (e.g., in the midwestern United States). Here, we report a source of resistance to Psprace 6 in pinto US 14 (PI 549748). Initially, plants derived from the original US 14 seed stock were variable for their resistance reaction. Thus, a pure‐line with resistance to Psprace 6, hereafter referred to as US14HBR6 (Reg. No. GP‐293, PI 666939), was jointly developed at the University of California, Davis and University of Idaho, Kimberly, through repeated individual plant selections and progeny tests performed under severe halo blight disease pressure. Pinto US14HBR6, like US 14, has an indeterminate prostrate growth habit Type III, white flowers, and 100‐seed weight of 23 g. US14HBR6 matures in approximately 95 d in southern Idaho.

Common bacterial blight (CBB) caused by Xanthomonas campestrispv. phaseoliand X. campestrispv. phaseolivar. fuscansis a seed‐borne disease that can significantly reduce yield and seed quality of common bean (Phaseolus vulgarisL.). Disease resistance is the most effective management strategy, but most common bean cultivars have no CBB resistance. Marker‐assisted selection (MAS) shows promise as a method to facilitate pyramiding CBB resistance between common bean gene pools. This study compared the efficiency of direct disease resistance selection (DDS) and MAS for the pyramiding and transfer of CBB resistance into dark red kidney bean. Direct disease resistance selection and MAS were applied independently, from the F1through the F5, in an inter‐gene pool double‐cross population, Wilkinson 2/dark red kidney (DRK) 2//DRK 1/VAX 3. Replicated trials were performed in the greenhouse and field in 2006 and 2007 to assess levels of CBB resistance in 15 breeding lines independently developed with each method. Under high disease pressure, in two greenhouse environments, 12 resistant breeding lines were obtained with DDS compared with six using MAS, and the overall CBB mean disease severity index was 3.3 for DDS and 4.2 for MAS. Under moderate disease pressure in the field, there was no significant difference (p> 0.05) between the responses of breeding lines developed by the two selection methods. The cost of DDS was US$1.55 per plant compared to $2.03 for MAS.

The low melting point, negligible vapor pressure, good solubility, and thermal and chemical stability make ionic liquids useful materials for a wide variety of applications. Polyoxometalates are early transition metal oxygen clusters that can be synthesized in many different sizes and with a variety of heterometals. The most attractive feature of POMs is that their physical properties, in particular electrical, magnetic, and optical properties, can be easily modified following known procedures. POM ionic liquids can be obtained by selecting the appropriate cation. Different alkyl ammonium and alkyl phosphonium salts are being used to produce new POM ionic liquids together with organic or inorganic luminescent centers to design light emitting materials. Ammonium and phosphonium cations with activated, polymerizable groups are being used to further polymerize the ionic liquid into transparent, solid materials with high metal densities.

Four new species of corticioid fungi from Hawaii are described and illustrated. The new genus Hemmesomycesis described to accommodate the new species H. puauluensis. Radulomyces tantalusensis, Crustoderma fuscatumand Scopuloides magnacystidiataalso are described as new. In addition, the new combination Crustoderma vulcanenseis proposed. Keys to the species of Crustoderma, Radulomycesand Scopuloidesare provided.

Alternaria radicina, A. carotiincultae, and A. petroseliniare closely related pathogens of umbelliferous crops. Relationships among these fungi were determined based on growth rate, spore morphology, cultural characteristics, toxin production, and host range. Random amplified polymorphic DNA (RAPD) analysis of these species, other species of Alternaria, and closely related fungi was also performed. A. petroseliniwas readily differentiated from A. radicinaand A. carotiincultaeon the basis of spore morphology, production of microsclerotia, host range, and RAPD analysis. Alternaria radicinaand A. carotiincultaewere considerably more similar to each other than to A. petroselini, but could be differentiated on the basis of growth rate, spore morphology, colony morphology, and, to a limited extent, RAPD analysis. When grown on media having a high nutritional content, A. radicinaproduced a diffusible yellow pigment and crystals of the fungal metabolite radicinin. In contrast, A. carotiincultaeproduced little or no radicinin. However, when A. carotiincultaewas grown on the same medium amended with radicinin, growth rate and colony and conidial morphology were more similar to those of A. radicina. These results suggest that the morphological differences between A. radicinaand A. carotiincultaeare due, at least in part, to radicinin production, and that these fungi are conspecific. Therefore, we propose that A. carotiincultaebe considered a synonym of A. radicina.

The functional properties of proteins [capsid protein (CP), V1, and C4] potentially involved with movement of the monopartite begomovirus, Tomato yellow leaf curl virus(TYLCV), were investigated using microinjection of Escherichia coliexpressed proteins and transient expression of GFP fusion proteins. The TYLCV CP localized to the nucleus and nucleolus and acted as a nuclear shuttle, facilitating import and export of DNA. Thus, the CP serves as the functional homolog of the bipartite begomovirus BV1. The TYLCV V1 localized around the nucleus and at the cell periphery and colocalized with the endoplasmic reticulum, whereas C4 was localized to the cell periphery. Together, these patterns of localization were similar to that of the bipartite begomovirus BC1, known to mediate cell-to-cell movement. However, in contrast to BC1, V1 and C4, alone or in combination, had a limited capacity to move and mediate macromolecular trafficking through mesophyll or epidermal plasmodesmata. Immunolocalization and in situPCR experiments, conducted with tomato plants at three stages of development, established that TYLCV infection was limited to phloem cells of shoot apical, leaf, stem, and floral tissues. Thus, the V1 and/or C4 may be analogs of the bipartite begomovirus BC1 that have evolved to mediate TYLCV movement within phloem tissue.

From the crude mixtures of isomeric 4‐nitrophenylthieno[2,3‐b]pyridines (3) previously reported [1] were isolated three analytically pure samples, viz.the 2‐isomer (yellow needles, mp 258°, 3a), the 6‐isomer (red prisms, mp 182°, 3e), and a ternary mixture of the 2‐, 3‐, and 4‐isomers (orange needles, mp 213°, 3a:3b:3c= 1.3:1.0:0.5). The 258° compound was identified as either 3aor 3bby its 1H nmr spectrum and definitively as the former by its x‐ray crystallographic analysis. The isomeric identities of the 182° and 213° samples were established from their 1H nmr spectra only. No 5‐isomer (3d) was identified. Semi‐quantitatively, relative isomeric yields fit the pattern 2‐ (64%)>>6‐ (14%)≥3‐ (12%)>4‐ (6%)≥5‐(≤4%). Crystallographic data for 3aare presented.

To elucidate relationships among Alternaria, Ulocladium, and Stemphylium species, nuclear internal transcribed spacer (ITS) and mitochondrial small subunit (SSU) ribosomal DNA (rDNA) sequences from 18 Alternaria, four Ulocladium and four Stemphylium spp. were determined and compared. Phylogenetic analysis of the ITS and SSU rDNA sequences, performed by the neighbour joining and maximum parsimony methods, revealed that the Stemphylium spp. were phylogenetically distinct from the Alternaria and Ulocladium spp. Most Alternaria spp. and the Ulocladium spp. were placed together in a large Alternaria/Ulocladium clade. Within this large clade, the Alternaria spp. clustered into several distinct species-clades, most of which correlated with species-groups previously established based upon morphological characteristics. The Ulocladium spp. were placed into two species-clades, each of which also included Alternaria spp. A. longissima was distantly related to the other Alternaria spp., as well as the Ulocladium and Stemphylium spp. Based upon ITS and nuclear 18S rDNA sequence identities, A. longissima was most closely related to Leptosphaeria.

Formation of valence isomers of metallabenzenesis now possible from a lithiated 3‐vinyl‐1‐cyclopropene and Vaska‐type complexes. Upon heating, the resultant metallacycle, iridabenzvalene 1, cleanly rearranges to iridabenzene 2by means of a transformation that is reminiscent of a valence isomerization.

Products formed from dehydrative cyclization of cyclopentanone, cyclohexanone, and cycloheptanone with anthranilamide 2 under neutral or acidic conditions are established as the spiro compounds 2,2polymethylene1,2,3,4tetrahydroquinazolin4ones 6by means of a the presence of a 13C nmr signal at 66–79 ppm for atom C2 and b Xray crystallography on the tetramethylene compound 6a. Analogously, products from reactions of these cycloalkanones with 3amino2carbamoylthiophene are now shown by 13C nmr spectra to have structures isosteric to 6, i.e.5,5polymethylene4,5,6,7tetrahydrothieno2,3epyrimidin7ones 5, rather than the chelate ring structures previously proposed. Additionally, conflicting literature reports on product 3from reaction of acetone with 2are partially clarified. Correlation of 13C chemical shifts in systems 3, 5, and 6is presented.

The role of bean common mosaic necrosis potyvirus (BCMNV) and lettuce mosaic potyvirus (LMV) proteins was investigated in terms of their capacity to function as viral movement proteins (MPs). UsingEscherichia coli-expressed proteins and microinjection techniques, direct evidence was obtained that both the potyviral capsid protein (CP) and helper component- proteinase (HC-Pro) function in this capacity, in that both proteins (a) trafficked from cell to cell, (b) induced an increase in plasmodesmal size exclusion limit, and (c) facilitated cell-to-cell movement of viral RNA. CP and HC-Pro mutants were also produced and used in microinjection experiments. Mutations in the core region of the CP either impaired (single and double amino acid substitution mutants) or abolished (triple amino acid substitution mutant) cell-to-cell movement, as did C-terminal deletion mutants in HC-Pro. The BCMNV P1, CI, NIa, and NIb proteins did not exhibit viral MP properties, but NIa and NIb proteins were found to accumulate within the nuclei of injected cells. These results further establish the multifunctional nature of the potyvirus CP and HC-Pro.

Bean golden mosaic virus (BGMV) is a whitefly-transmitted, ssDNA geminivirus with a bipartite genome. AC1 is the only ORF required for geminiviral replication. A putative NTP-binding motif, EGX₄GKTX₃₂DD, was present in the derived amino acid sequence of the replication-associated protein from the AC1 ORF for 13 geminiviruses including BGMV-GA (Guatemalan isolate, amino acids 221-263). We analyzed the phenotypes of mutations within this domain using a rapid and sensitive PCR-based assay for geminiviral replication developed for these studies. Replication in tobacco cells (NT-1 suspension cells) and infection of beans were abolished when codons were changed from K228 to H or D262 to R within the putative NTP-binding site. A temperature-sensitive replication phenotype was conferred by changing E221 to R within the putative NTP-binding domain. Replication was unaffected by changing a nonconserved codon near the putative NTP-binding domain from I190 to R. Our results demonstrate that the putative NTP-binding domain is required for geminiviral replication. The role of NTP hydrolysis and the possible value of these mutants in a trans-dominant interference scheme for virus-derived resistance are discussed. Copyright 1995, 1999 Academic Press

The original description ofFomes occidentalisOverh, is validated by a Latin diagnosis. The new combinationsPhellinus occidentalis andPhellinus repandus are proposed. These fungi are known only from western North America. Morphological characters of basidiocarps and cultures of the two species are given with data on their distribution, substratum relationships, associated rot, and relation to similar species.

The X-ray crystal structure of 3-ethynylcyclopropene shows that the carbon–carbon double bond of the molecule is unusually short [1.255(2) Å], whereas theoretical calculations suggest a relative insensitivity of the bond length to adjacent orbital interactions.

Focuses on the penalties imposed by courts to spoliation or the destruction of evidence or failure to preserve property for use by another. Sanctions faced by spoliators in civil litigation; Court rulings imposing sanctions against spoliators; Discussion on a spoliator's degree of fault; Impact of such sanctions on insurance companies.

The low melting point, negligible vapor pressure, good solubility, and thermal and chemical stability make ionic liquids useful materials for a wide variety of applications. Polyoxometalates are early transition metal oxygen clusters that can be synthesized in many different sizes and with a variety of heterometals. The most attractive feature of POMs is that their physical properties, in particular electrical, magnetic, and optical properties, can be easily modified following known procedures. POM ionic liquids can be obtained by selecting the appropriate cation. Different alkyl ammonium and alkyl phosphonium salts are being used to produce new POM ionic liquids together with organic or inorganic luminescent centers to design light emitting materials. Ammonium and phosphonium cations with activated, polymerizable groups are being used to further polymerize the ionic liquid into transparent, solid materials with high metal densities.

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ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 100 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.

ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 100 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.

ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 100 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.