Asian soybean rust, caused by Phakopsora pachyrhizi Sydow, has been known to occur in the eastern hemisphere for nearly a century. More recently, it was reported from Hawaii in 1994, eastern and southern Africa from 1996-1998, Nigeria in 2001, and Brazil and Paraguay in 2002. Aerobiological models suggested that urediniospores of the pathogen would be disseminated on wind currents to the continental United States in association with tropical storms if the disease became established north of the equator during hurricane season (U.S. Soybean Rust Detection and Aerobiological Modeling online publication at www.aphis.usda.gov/ppq/ ep/soybean_rust/ ). Since soybean rust was observed at approximately 5°N latitude in South America before several hurricanes impacted the continental United States in September 2004, it seems likely that the introduction was associated with at least one of these tropical storms, especially hurricane Ivan. Symptoms of the disease were first observed on soybean (Glycine max (L.) Merr.) in the continental United States on November 6, 2004 in a field near Baton Rouge, LA. Typical pustules and urediniospores on infected leaves were readily apparent when viewed with a dissecting microscope. Urediniospores were obovoid to broadly ellipsoidal, hyaline to pale yellowish brown with a minutely echinulate thin wall, and measured 18 to 37 × 15 to 24 μm. Paraphyses were cylindric to clavate and slightly thickened at the apex, colorless to pale yellowish brown, and 25–50 × 6–14 μm in size. This morphology is typical of Phakopsora pachyrhizi and P. meibomiae, a less aggressive, western hemisphere species (2). DNA was extracted from leaves containing sori using the Qiagen DNeasy Plant Mini kit. P. pachyrhizi was detected using a real-time polymerase chain reaction (PCR) protocol (1) that differentiates between P. pachyrhizi and P. meibomiae performed in a Cepheid thermocycler with appropriate positive and negative controls. The PCR master mix was modified to include OmniMix beads (Cepheid). The field diagnosis of P. pachyrhizi was confirmed officially by the USDA/APHIS on November 10, 2004, and this was followed on November 11, 2004 by a wide-ranging survey of soybean and kudzu (Pueraria sp.) in soybean production areas in southern and central Louisiana. Collections from this survey also were assayed as described above, and six soybean specimens from five sites were confirmed positive. The disease was not found on kudzu samples. To our knowledge, this is the first report of P. pachyrhizi in the continental United States. Voucher specimens have been placed in the USDA National Fungus Collection. References: (1) R. D. Frederick et al. Phytopathology 92:217, 2002. (2) Y. Ono et al. Mycol. Res. 96:825, 1992.
A rust of daylilies was introduced recently into North and Central America. In order to confirm the identity of this rust as Puccinia hemerocallidis, numerous specimens from Costa Rica and the United States were examined morphologically and compared with specimens from China, Japan, Russia, and Taiwan. In addition, the internal transcribed spacer (ITS) region of the ribosomal DNA was sequenced from six representative fresh specimens from the Americas and Asia. We conclude that the rust introduced into the Americas is P. hemerocallidis, for which a modern description is provided with illustrations of the uredinial and telial stages.
Conspicuous galls and witches' brooms frequently are symptoms of rust infections on plant hosts in the ecologically diverse northwestern region of Argentina. These symptoms are caused by systemic or locally systemic spermogonial-aecial infections, although uredinial and telial infections also might be involved. Sixteen species of rust fungi are treated in this paper, most of which cause a plant response that results in enlarged growth. Ypsilospora tucumanensis J.R. Hern. & J.F. Hennen on Inga edulis is described as a species new to science. Puccinia cordiae Arthur is cited as a new record for Argentina. These rusts also are included: Chaconia ingae, Gerwasia imperialis, Kuehneola loeseneriana, Prospodium appendiculatum, Prospodium elegans, Prospodium perornatum, Puccinia bougainvilleae, Puccinia pampeana, Ravenelia argentinica, Ravenelia hieronymi, Ravenelia papillosa, Ravenelia spegazziniana, Uromyces cestri and Uropyxis rickiana. For some of the scientific names, lectotype specimens have been designated.
Abstract. The ISO Data Archive (IDA) and the XMM-Newton Science Archive (XSA) have been developed by the Science Operations and Data Systems Division of ESA in Villafranca, Spain. They are both built using the same flexible and modular 3-tier architecture: Data Products and Database, Business Logic, User Interface. This open architecture, together with Java and XML technology have helped in making the IDA and XSA inter-operable with other archives and applications. The various accesses from the IDA and the XSA to remote archives are described as well as the mechanism to directly access these ESA archives from remote archives Open and Flexible 3-Tier ArchitectureThe IDA and the XSA were both built-by a common team-using the open 3-tier architecture described in Figure 1. The main goal of this architecture is to separate the data from the presentation, which allows a more modular and flexible development.As the data volume is not that big, data are saved on magnetic disks for fast access as a normal UNIX file system. From the data products, metadata is extracted and put in a Relational Data Base, SYBASE. Note that the data ingestion from the data producer and the metadata extraction are separate processes to allow new metadata data extraction when user requirements evolve.The middle tier, also called the Business Logic, provides transparent access to the data products and to the metadata. This key layer has been developed in Java and XML and resides on the archive server.On the client side, several types of applications can be found. The standard IDA and XSA User Interface is a Java applet downloaded by the end user to access the archive content.Remote applications and other archives can also have access to the data and the metadata, bypassing the standard User Interface, by speaking to the Business Logic that will provide them with the required services via Java Server Pages.This architecture is especially powerful in the context of the worldwide Virtual Observatory initiatives where archives will all have to interoperate in a manner transparent to the end user. 47
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