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Persistent, symptomless, systemic, and seed-borne infection of lettuce by Botrytis cinerea
Experiments are presented which show that Botrytis cinerea, the cause of gray mould disease, is often present in symptomless lettuce plants as a systemic, endophytic, infection which may arise from seed. The fungus was isolated on selective media from surface sterilized sections of roots, stem pieces and leaf discs from symptomless plants grown in a conventional glasshouse and in a spore-free air-flow provided by an isolation propagator. The presence of B. cinerea was confirmed by immuno-labelling the tissues with the Botrytis-specific monoclonal antibody BC-12.CA4. As plants grew, infection spread from the roots to stems and leaves. Surface sterilization of seeds reduced the number of infected symptomless plants. Artificial infection of seedlings with dry conidia increased the rate of infection in some experiments. Selected isolates were genetically finger-printed using microsatellite loci. This confirmed systemic spread of the inoculating isolates but showed that other isolates were also present and that single plants hosted multiple isolates. This shows that B. cinerea commonly grows in lettuce plants as an endophyte, as has already been shown for Primula. If true for other hosts, the endophytic phase may be as important a component of the species population as the aggressive necrotrophic phase
Gene tree reconciliation: new developments in Bayesian concordance analysis with BUCKy
When phylogenetic trees inferred from different genes are incongruent, several methods are available to reconcile gene trees and extract the shared phylogenetic information from the sequence data. Bayesian Concordance Analysis, implemented in BUCKy, aims to extract the vertical signal and to infer clusters of genes that share the same tree topology. The new version of BUCKy includes a quartet-based estimate of the species tree with branch lengths in coalescent units
Concanavalin A-Binding Enzymes of Crotalus scutulatus scutulatus Venom
Crotalus scutulatus scutulatus crude venom was separated into two fractions by Concanavalin A Sepharose 4B affinity chromatography. The proteins binding to Con A exhibited phosphomonoesterase (orthophosphoric monoester phosphohydrolase EC 3.1.3.2), phosphodiesterase, 5\u27-nucleotidase (5\u27-ribonucleotide phosphohydrolase EC 3.1.3.5), phospholipase A(phosphatidate 2-acylhydrolase EC 3.1.1 .4), hyaluronidase (hyaluronate glycanohydrolase EC 3.2.1 d), N-benzoyl-L-arginine ethyl esterase, p-toluenesulfonyl-L-arginine methyl esterase, L-amino acid oxidase (L-amino acid: 02 oxidoreductase [deaminating] EC 1.4.3.2), and caseinolytic activities. Thrombin-like and NAD nucleosidase (5\u27-ribonucleotide phosphohydrolase EC 3.1.3.5) activities were not observed. The crude venom and the fraction containing the glycoproteins which bound to Con A were fractionated by DEAE Sephadex A-50 ion exchange chromatography. Each of these samples yielded fractions having caseinolytic activities
Concanavalin A-Nonbinding Enzymes of Crotalus scutulatus scutulatus Venom
Crotalus scutulatus scutulatus crude venom was separated into two fractions by Concanavalin A Sepharose 4B affinity chromatography. The Concanavalin A-nonbinding fraction (F-l) exhibited phosphomonoesterase (orthophosphoric monoester phosphohydrolase EC 3.1 .3.2), phosphodiesterase, 5 \u27-nucleotidase (5 \u27-ribonucleotide phosphohydrolase EC 3.1.3.5), phospholipase A (phosphatidate 2-acylhydrolase EC 3.1.1.4), hyaluronidase (hyaluronate glycanohydrolase EC 3.2.1.d), N-benzoyl-Larginine ethyl esterase, p-toluenesulfonyl-L-arginine methyl esterase, L-amino acid oxidase (L-amino acid: O2 oxidoreductase [deaminating] EC 1.4.3.2), and caseinolytic activities. Thrombin-like and NAD nucleosidase (5 \u27-ribonudeotide phosphohydrolase EC 3.1.3.5) activities were not observed. DEAE Sephadex A-50 ion exchange chromatography by two stage elution of F-l yielded several fractions having proteinase activities. Proteinase activity was observed in the latter fractions of the first elution and in the fractions of the second elution
Futurity Beyond the State: Illegal Markets and Imagined Futures in Latin America
Social Science Perspectives on Futurity Futurity in Illegal Economies The Legality and Legitimacy Factors Specifying Illegality: The Legality Factor Morality in Illegal Markets: The Legitimacy Factor Morality, Illegal Markets, and Futurity Hope In and Of the State Conclusions Footnotes Reference
Drift of Terrestrial Arthropods in an Irrigation Canal Following a Wide-Area Application of ULV Malathion
Numbers of arthropods drifting in an irrigation canal were recorded at 30-min intervals during and after an upstream application of ULV malathion. Flower-visiting and parasitic Hymenoptera were the first insects to increase; a bimodal drift pattern resulted from an interruption in the spray application. Diptera exhibited a delayed response but the numbers collected, especially Paracantha culta (Wiedemann), suggest high susceptibility. Ants occurred in large numbers over a long period, but mortality was probably low. Miridae and Cicadellidae were probably more susceptible than Orthoptera and adult Odonata but had similar delayed drift patterns. Tetragnathidae were the most, and Thomiscidae the least, susceptible spiders
Trends in Modern War Gaming: The Art of Conversation
Lieutenant William McCarty Little—a war-gaming visionary—was truly a man ahead of his time.1 Although physically sight impaired and medically retired from active naval service, he opted to use his ideational vision and keen mind to support the Naval War College, in Newport, Rhode Island, during its first few years of operation after its founding in 1884. Initially an unpaid volunteer, he was appointed in 1887 as a member of the faculty, where he developed two-sided war gaming at the College—a construct that is still in use at the state-of-the-art facility that today bears his name
Ionization Structure and the Reverse Shock in E0102-72
The young oxygen-rich supernova remnant E0102-72 in the Small Magellanic
Cloud has been observed with the High Energy Transmission Grating Spectrometer
of Chandra. The high resolution X-ray spectrum reveals images of the remnant in
the light of individual emission lines of oxygen, neon, magnesium and silicon.
The peak emission region for hydrogen-like ions lies at larger radial distance
from the SNR center than the corresponding helium-like ions, suggesting passage
of the ejecta through the "reverse shock". We examine models which test this
interpretation, and we discuss the implications.Comment: 4 pages, 6 figures; To appear in "Young Supernova Remnants" (11th
Annual Astrophysics Conference in Maryland), S. S. Holt & U. Hwang (eds),
AIP, New York (2001
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