scholarly journals Puccinia acroptili on Russian Knapweed in Colorado, Montana, and Wyoming

Plant Disease ◽  
2006 ◽  
Vol 90 (7) ◽  
pp. 971-971 ◽  
Author(s):  
W. L. Bruckart ◽  
F. M. Eskandari ◽  
M. C. Becktell ◽  
D. Bean ◽  
J. Littlefield ◽  
...  

Acroptilon repens (L.) DC. (Russian knapweed) is a long-lived perennial weed from central Asia that is widely distributed in the western United States (U.S.). Recently, accessions of a rust disease were collected from Colorado (CO), Montana (MT), and Wyoming (WY) for comparison with Eurasian isolates. U.S. accessions had two-celled teliospores with slight constrictions in the middle and urediniospores with three germ pores ± equatorial in location. Urediniospores were (state, width × length, [n = 100]): CO, 16.4 to 25.7 × 19.2 to 27.0 μm; MT, 18.4 to 23.1 × 17.4 to 24.6 μm; and WY, 18.0 to 26.2 × 20.2 to 26.7 μm. These were similar to those of 16.6 to 25.7 × 21.2 to 28.0 μm from two New Mexican (NM) herbarium specimens (BPI Nos. 1107952 and 1110177) (1). Teliospores measured 19.9 to 27.7 × 29.8 to 47.4 μm, 17.4 to 26.0 × 32.4 to 44.2 μm, 16.5 to 27.5 × 29.4 to 45.7 μm, and 18.7 to 27.6 × 31.0 to 46.4 μm for CO, MT, WY, and NM accessions, respectively. These rust isolates have been identified as Puccinia acroptili Syd. on the basis of host plant record and spore morphology (2). To our knowledge, this is the first record of P. acroptili in CO, MT, and WY. Besides NM, P. acroptili has been reported in North America from California, British Columbia, and Saskatchewan. References: (1) M. E. Palm and S. G. Vesper. Plant Dis. 75:1075, 1991. (2) D. B. O. Savile. Can. J. Bot. 48:1567, 1970.

Plant Disease ◽  
2001 ◽  
Vol 85 (12) ◽  
pp. 1290-1290 ◽  
Author(s):  
S. T. Koike ◽  
R. F. Smith

Wild garlic (Allium vineale) is a bulbous perennial weed that was introduced from Europe and is now established throughout the eastern and much of the western United States. In 2001, wild garlic plants growing in Monterey County, CA were infected with a rust fungus. Uredinia and telia were present on leaves, resulting in small (2 to 5 mm long) lesions; however, leaf dieback and other symptoms were not observed. The orange urediniospores were spherical to ellipsoidal, echinulate, and mea-sured 26 to 30 × 25 to 28 μm. Telia were black in mass and divided into locules by fused paraphyses. Teliospores were located within the locules and were brown, smooth-walled, two-celled, and measured 40 to 50 × 17 to 20 μm. Teliospore pedicels were hyaline, usually fractured, and measured 3 to 15 μm. One-celled mesospores were not observed. Based on these morphological characteristics, the pathogen was identified as Puccinia allii (1,2). To our knowledge, this is the first report of rust caused by P. allii on wild garlic in California. Because of this finding, an experiment was designed to determine whether wild garlic could be a source of rust inoculum for commercial allium crops. Wild garlic bulbs were planted in 4-in. pots (10 cm square) and grown in a greenhouse. At the 4- to 5-leaf stage the plants were transplanted in a garlic (Allium sativum) cultivar trial that had been inoculated with an isolate of P. allii from garlic. When plants were evaluated 2 months later, uredinia and telia were observed on the wild garlic plants, and the fungus was confirmed to be P. allii. Wild garlic, therefore, could be a source of overwintered inocula for the rust disease that occurs on commercial garlic and onion (A. cepa) in California (2). References: (1) D. M. Jennings et al. Mycol. Res. 94:83, 1990. (2) S. T. Koike et al. Plant Dis. 85:585, 2001.


Plant Disease ◽  
2001 ◽  
Vol 85 (3) ◽  
pp. 335-335 ◽  
Author(s):  
M. Scholler ◽  
Arthur Herbaria ◽  
Kriebel Herbaria ◽  
S. T. Koike

Common groundsel (Senecio vulgaris, Asteraceae) is native to Europe and is now a common weed mainly in disturbed habitats of almost worldwide distribution. In November 2000, groundsel plants growing adjacent to lettuce fields in California's coastal Salinas Valley (Monterey County) showed symptoms of rust. In a 0.2-ha survey area, 75% of the plants were infected. Examination of weeds growing in four residential blocks also uncovered infected groundsel. Densely clustered, orange aecia were observed on leaves and stems. Stems were swollen where aecia had formed. Blossom and fruit formation was not notably reduced, although some involucral bracts were infected. Aeciospores measured 14 to 18 μm × 12.5 to 15 μm (fresh material). Telia were not found. The pathogen was identified as Puccinia lagenophorae Cooke, a rust fungus that is native to Australia and New Zealand and infects plants of the subfamily Asteroideae (family Asteraceae) (3). P. lagenophorae is an autoecious species forming only repeating aecia (stage I) and telia (stage III). There are six other rusts of Senecio that occur in the United States (1) that readily form aecia but not telia on Senecio spp. When only aecia are observed on Senecio, which is typical for P. lagenophorae (2), the following features can be used to differentiate it from these other species: no pycnia (stage 0) are formed; aecia are formed repeatedly; systemic growth that results in deformation of the host, including formation of galls with dense clusters of aecia on the stem; poorly developed aecial peridium; and aeciospores small, measuring 12.5 to 18.5 μm × 10.0 to 16.0 μm (4). In addition, P. lagenophorae forms aecia even at the end of the year in northern temperate zones, whereas heteroecious species form aecia only in spring and early summer (2). This is the first record of P. lagenophorae in North America. Specimens were deposited in the Arthur Herbarium, Purdue University. Outside its native habitat, this fungus has been found in Europe, Africa, the Middle East, and South America. There are about 60 known host species of P. lagenophorae (3) including ornamentals such as Bellis perennis, Calendula officinalis, and Senecio cruentus. The pathogen may have been introduced to North America via land from South America through Central America, or by the importation of ornamentals that were either infected with rust or infested with diseased groundsel. References: (1) D. F. Farr et al. 1989. Fungi on Plants and Plant Products in the United States. American Phytopathological Society, St. Paul, MN. (2) M. Scholler. Regensb. Myk. Schr. 6:1, 1996. (3) M. Scholler. J. Plant Dis. Prot. 105:239, 1998. (4) I. Wilson et al. Trans. Brit. Mycol. Soc. 48:501, 1965.


2018 ◽  
Vol 93 (2) ◽  
pp. 278-290
Author(s):  
J. Mark Erickson

AbstractIn midcontinent North America, the Fox Hills Formation (Upper Cretaceous, upper Maastrichtian) preserves the last marine faunas in the central Western Interior Seaway (WIS).Neritoptyx hogansoninew species, a small littoral snail, exhibited allometric change from smooth to corded ornament and rounded to shouldered shape during growth. Specimens preserve a zig-zag pigment pattern that changes to an axial pattern during growth.Neritoptyx hogansoninew species was preyed on by decapod crustaceans, and spent shells were occupied by pagurid crabs. Dead mollusk shells, particularly those ofCrassostrea subtrigonalis(Evans and Shumard, 1857), provided a hard substrate to which they adhered on the Fox Hills tidal flats. This new neritimorph gastropod establishes a paleogeographic and chronostratigraphic proxy for intertidal conditions on the Dakota Isthmus during the late Maastrichtian. Presence of a neritid extends the marine tropical/temperate boundary in the WIS northward to ~44° late Maastrichtian paleolatitude. Late Maastrichtian closure of the isthmus subsequently altered marine heat transfer by interrupting northward flow of tropical currents from the Gulf Coast by as much as 1 to 1.5 million years before the Cretaceous ended.UUID:http://zoobank.org/3ba56c07-fcca-4925-a2f0-df663fc3a06b


Plant Disease ◽  
2006 ◽  
Vol 90 (1) ◽  
pp. 112-112
Author(s):  
E. Lewis Roberts ◽  
J. F. White

Purple fountain grass (Pennisetum alopecuroides) is indigenous to Asia, prized for its foxtail-like purple flowers, and widely used as an ornamental. During October 1999, black choke disease was found on P. alopecuroides cv. Hameln (L.) Spreng at a plant nursery in Maryland. Disease symptoms include mummification of inflorescences by black conidial stromata, distorted leaf tissue, and a dense layer of white epiphytic mycelium on the adaxial leaves and culms. Stromata were initially white but became black with age. Microscopic analysis of the isolated fungus indicated that the causal organism was an Ephelis sp., American Type Culture Collection No. MYA-3317. The ephelidial conidia developed in sporodochia on stromata and were hyaline, filiform to acicular, and 18 to 21 × 1 μm. Cultures on potato dextrose agar were off-white and 50 mm in diameter after 14 days at 23°C. Analysis of herbarium specimens of several Balansia spp. revealed that the Ephelis sp. isolate bears morphological resemblance to Asian and not American Balansieae. In fact, the infection observed on Pennisetum sp. forms similarly to Ephelis sp. infection on Oryza sativa L. (Asian) that also results in development of stromata on panicles and a mycelial network enclosing the panicles, preventing maturation and expansion. On both plants, the infected inflorescence becomes black with age and appears mummified as pseudosclerotia form. Furthermore, flag leaves and tillers of both plants appear slightly distorted and silver due to the epibiotic mycelia. The causal agent of black choke disease on rice is Ephelis oryzae Syd. (teleomorph = Balansia oryzae-sativae Hashioka). The mature stroma of E. oryzae forms on the inflorescence and is embedded with a layer of ovate perithecia. Immature stromata bear conidiomata that are cupulate to cushion shaped and black, producing hyaline, branched conidiophores that terminate in phialides. Conidia are ephelidial, filiform to acicular, hyaline, and 18 to 22 × 1.5 μm (2). To determine the phylogenetic relationship between other balansioid fungi and the Ephelis sp. isolate, the nuclear ribosomal internal transcribed spacer (ITS1) region was amplified with primers ITS4 and ITS5 (3). Maximum parsimony analysis of the ITS1 sequences showed that the Ephelis sp. infecting P. alopecuroides cv. Hameln grouped (100% bootstrap support) in a clade with Ephelis oryzae, Balansia sclerotica, Balansia andropogonis, and Balansia sp.; all endemic to Asia and tightly groups with the Asian rice pathogen Ephelis oryzae (100% bootstrap support). Further phylogenetic analysis using topological constraints indicated that Ephelis sp. is not appropriately grouped with American balansioid species. Since P. alopecuroides is often imported to North America from Asia (1), it is likely that Ephelis sp. on P. alopecuroides is endemic to Asia and perhaps was transported along with its host to North America. The disease ontogeny, morphology, and sequence similarities between the Ephelis sp. isolated from Pennisetum sp. and E. oryzae suggests that these fungi are evolutionarily close, sibling species, or conspecific. To our knowledge, this is the first report of choke disease on P. alopecuroides in the United States. References: (1) A. S. Hitchcock. Manual of the Grasses of the United States. A. Chase, ed. U.S. Government Print Office, Washington DC, 1951 (2) F. N. Lee and P. S. Gunnell. Udbatta. Page 29 in: Compendium of Rice Diseases. R. K. Webster and P. S. Gunnell, eds. The American Phytopathological Society, St. Paul. MN, 1992. (3) J. F. White Jr. et al. Mycologia 89:408, 1997.


1967 ◽  
Vol 99 (11) ◽  
pp. 1229-1229 ◽  
Author(s):  
P. G. Pilley ◽  
R. A. Trieselmann

The first record of the occurrence in North America of the white-tipped clover case-moth, Coleophora frischella L., was made in June 1966 when a single adult was taken by Heinemann on Picton Island, N.Y., in the St. Lawrence River (Freeman, personal communication). Independently, Trieselmann collected the larvae from white sweet-clover, Melilotus alba Desr., on 28 July through to 8 August 1966 at many points around Pembroke, Ont. Detailed examinations made at two of the collection points indicated that between 15 and 20% of sweetclover seeds were damaged. Because of its potential economic significance, the authors wish to make the presence of this species known to agricultural entomologists in Canada and the United States.


1976 ◽  
Vol 66 (5) ◽  
pp. 1609-1622 ◽  
Author(s):  
Zoltan A. Der ◽  
Thomas W. McElfresh

abstract Average Q values were determined for ray paths to various LRSM stations from the SALMON nuclear explosion by taking ratios of observed P-wave spectra to the estimated source spectrum. Most Q values for P-wave paths throughout eastern North America are in the range 1600 to 2000 while those crossing over into the western United States are typically around 400 to 500. These differences in Q for intermediate distances can sufficiently explain the differences in the teleseismic event magnitudes observed, 0.3 to 0.4 magnitude units, in the western versus the eastern United States, if one assumes that the low Q layer under the western United States is located at depths less than 200 km.


1993 ◽  
Vol 83 (4) ◽  
pp. 1064-1080 ◽  
Author(s):  
G. A. Bollinger ◽  
M. C. Chapman ◽  
M. S. Sibol

Abstract This study investigates the relationship between earthquake magnitude and the size of damage areas in the eastern and western United States. To quantify damage area as a function of moment magnitude (M), 149 MMI VI and VII areas for 109 earthquakes (88 in the western United States, 21 in the eastern United States and Canada) were measured. Regression of isoseismal areas versus M indicated that areas in the East were larger than those in the West, at both intensity levels, by an average 5 × in the M 4.5 to 7.5 range. In terms of radii for circles of equivalent area, these results indicate that damaging ground motion from shocks of the same magnitude extend 2 × the epicentral distance in eastern North America compared to the West. To determine source and site parameters consistent with the above results, response spectral levels for eastern North America were stochastically simulated and compared with response spectral ordinates derived from recorded strong ground motion data in the western United States. Stress-drop values of 200 bars, combined with a surficial 2-km-thick low velocity “sedimentary” layer over rock basement, produced results that are compatible with the intensity observations, i.e., similar response spectral levels in the east at approximately twice their epicentral distance in the western U.S. distance. These results suggest that ground motion modeling in eastern North America may need to incorporate source and site parameters different from those presently in general use. The results are also of importance to eastern U.S. hazard assessments as they require allowance for the larger damage areas in preparedness and mitigation programs.


1999 ◽  
Vol 36 (8) ◽  
pp. 1257-1266 ◽  
Author(s):  
Corwin Sullivan ◽  
Robert R Reisz

Isolated skeletal elements of the amphibian genus Seymouria were recently discovered at the Richards Spur locality near Fort Sill, Oklahoma, a prolific source of Early Permian tetrapod remains. Five of the seven described bones are of juvenile size and include three neural arches, a humerus, and a femur, whereas the other two are partial vertebrae, apparently adult. All seven are morphologically similar to equivalent skeletal elements in Seymouria specimens previously collected in Europe and North America, apart from features reflecting the early developmental stage of the juvenile bones. The femur and humerus are clearly distinct from those of other seymouriamorphs such as Ariekanerpeton and Kotlassia. The rarity of Seymouria at the Richards Spur locality implies that it was not a regular component of the fauna, and it is also associated with the less markedly terrestrial assemblage that consistently occurs at localities in the southwestern United States. However, its skeletal morphology and occurrence at terrestrial localities such as Richards Spur imply a primarily terrestrial, rather than an amphibious, mode of life. Conflicting biostratigraphic correlations imply that the exact age of the Richards Spur deposits is uncertain, and equivalence to the Arroyo Formation of Texas may be erroneous.


1997 ◽  
Vol 129 (1) ◽  
pp. 93-104 ◽  
Author(s):  
Stewart B. Peck ◽  
Pedro Gnaspini

AbstractWe here give Echinocoleus new ranking as a subgenus of Ptomaphagus. Ptomaphagus (Echinocoleus) acutus sp.nov. is described from the southeastern United States (Alabama, Georgia, Florida). It is the most plesiotypic member of a group in which all other species live in the western United States and (probably) adjacent Mexico. All are myrmecophilous with Pogonomyrmex and Aphaenogaster (= Novomessor) harvester ants. A phylogenetic analysis is given for the subgenus. The main synapomorphies of Echinocoleus, which are mostly interrelated with myrmecophily, are reduction of body length and broadening of elytra, reduction of antennal length, verticalization of mesocoxal insertion, reduction of mesosternal carina, body with a golden pubescense, and a pointed projection at the end of the spermatheca.


The Auk ◽  
2005 ◽  
Vol 122 (4) ◽  
pp. 1070-1085 ◽  
Author(s):  
Jay D. Carlisle ◽  
Gregory S. Kaltenecker ◽  
David L. Swanson

Abstract Intraspecific patterns of autumn migration timing are not well known, particularly in the western United States. Here, we (1) describe autumn migration timing and age ratios of landbird migrants in southwestern Idaho, (2) examine differences in timing among age and sex classes, and (3) demonstrate how prebasic molt strategies affect migration timing differences between age classes. As a group, Neotropical migrants were most common from late July through early September, whereas temperate migrants were most common from mid-September into early October. Proportion of hatch-year birds was 74.5% for all migrants combined and ranged from 33.3% to 100% for individual species. Timing differences between sex classes were detected in only a few species and no general patterns emerged. In 22 of 31 Neotropical and temperate migrants examined, there were significant differences in timing between adults and hatch-year birds. In species in which adults begin fall migration before replacing flight feathers, adults migrated earlier than hatch-year birds. Conversely, in species in which adults molt flight feathers on or near the breeding grounds before departing on fall migration, hatch-year birds migrated earlier than adults in all but one case. Therefore, it appears that molt strategy is a powerful determinant of intraspecific migration timing differences and, to our knowledge, this is the first study to document this pattern among migrant passerines of North America. Estrategias de Muda y Diferencias en el Momento de Migración Otoñal en Migrantes Terrestres en el Suroeste de Idaho


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