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1.
Natal homing in a marine fish metapopulation   总被引:1,自引:0,他引:1  
Identifying natal origins of marine fishes is challenging because of difficulties in conducting mark-recapture studies in marine systems. We used natural geochemical signatures in otoliths (ear bones) to determine natal sources in weakfish (Cynoscion regalis), an estuarine-spawning marine fish, in eastern North America. Spawning site fidelity ranged from 60 to 81%, comparable to estimates of natal homing in birds and anadromous fishes. These data were in contrast to genetic analyses of population structure in weakfish. Our findings highlight the need for consideration of spatial processes in fisheries models and have implications for the design of marine reserves in coastal regions.  相似文献   
2.
The ethylene production of severalFusarium species and formae speciales in vitro was measured under comparable conditions. All of them produced ethylene.Fusarium oxysporum Schlecht. ex Fr. f.tulipae Apt. produced much more than the other 18 strains investigated.Samenvatting Aangezien er aanwijzingen zijn dat ethyleen een rol speelt bij de aantasting van de tulpebol doorFusarium, werd de ethyleenproduktie van diverse soorten en formae speciales vanFusarium onder standaardvoorwaarden in vitro vergeleken. Alle onderzochteFusarium spp. en vormen vanFusarium produceerden ethyleen.Fusarium oxysporum Schlecht. ex Fr. f.tulipae Apt. bleek in vergelijking met 18 andere getoetste soorten en formae speciales enige duizenden malen meer ethyleen te produceren.  相似文献   
3.
Swart JA 《Science (New York, N.Y.)》2003,299(5615):1981-2; author reply 1981-2
  相似文献   
4.
Freezing of fox carcasses to minimize professional hazard of infection with Echinococcus multilocularis is recommended in endemic areas, but this could influence the detection of Trichinella larvae in the same host species. A method based on artificial digestion of frozen fox muscle, combined with larva isolation by a sequential sieving method (SSM), was validated using naturally infected foxes from Latvia. The validated SSM was used to detect dead Trichinella muscle larvae (ML) in frozen muscle samples of 369 red foxes from the Netherlands, of which one fox was positive (0.067 larvae per gram). This result was compared with historical Trichinella findings in Dutch red foxes. Molecular analysis using 5S PCR showed that both T. britovi and T. nativa were present in the Latvian foxes, without mixed infections. Of 96 non-frozen T. britovi ML, 94% was successfully sequenced, whereas this was the case for only 8.3% of 72 frozen T. britovi ML. The single Trichinella sp. larva that was recovered from the positive Dutch fox did not yield PCR product, probably due to severe freeze-damage. In conclusion, the SSM presented in this study is a fast and effective method to detect dead Trichinella larvae in frozen meat. We showed that the Trichinella prevalence in Dutch red fox was 0.27% (95% CI 0.065-1.5%), in contrast to 3.9% in the same study area fifteen years ago. Moreover, this study demonstrated that the efficacy of 5S PCR for identification of Trichinella britovi single larvae from frozen meat is not more than 8.3%.  相似文献   
5.
Rooibos and honeybush teas significantly (P < 0.05) enhanced the activity of cytosolic glutathione S-transferase alpha. A significant (P < 0.05) to marginal (P < 0.1) increase in the activity of the microsomal UDP-glucuronosyl transferase was obtained with unprocessed rooibos and honeybush teas, respectively. Oxidized glutathione (GSSG) levels were significantly (P < 0.05) reduced in the liver of all tea treated rats while reduced glutathione (GSH) was markedly increased in the liver of the herbal tea treated rats. These changes resulted in a significant (P < 0.05) increase in the GSH/GSSG ratio by the unprocessed, processed rooibos and unprocessed honeybush teas. Green and black teas markedly to significantly decreased the oxygen radical absorbance capacity in liver homogenates, respectively. Modulation of phase II drug metabolizing enzymes and oxidative status in the liver may be important events in the protection against adverse effects related to mutagenesis and oxidative damage.  相似文献   
6.
7.
Regular worm counts were done post-mortem on sheep that had grazed on Kikuyu pastures at the Elsenburg Research Station near Stellenbosch, a winter rainfall region. Major species were Trichostrongylus colubriformis, Trichostrongylus axei, while Ostertagia circumcincta was usually present in large numbers. Minor species were Haemonchus contortus, Nematodirus spathiger, Dictyocaulus filaria, Oesophagostomum venulosum, Trichuris spp., Chabertia ovina and larvae of the arthropod Oestrus ovis. Muellerius capillaris caused the formation of nodules in the lungs but were not counted. The trial started in April 1982 and was concluded in March 1984. One hundred and four sheep died or were slaughtered and 99 were examined post-mortem during this period. Total worm burdens rose to a peak of 88,763 (range 67,281-124,735) worms in March 1983, i.e. sheep mortality was such that the flock had to be treated with an anthelmintic in April 1983 to prevent further losses. Kikuyu pastures provide shade, form an excellent mat, the humus layer under the grass retains moisture and is an excellent incubator for preinfective larvae and a protector for infective larvae. If these qualities are combined with more than 100 mm of rain in spring and summer, Kikuyu pastures are a paradise for the free-living stages.  相似文献   
8.
ABSTRACT

Separate volume regression equations for pulpwood, sawtimber and over-mature Eucalyptus grandis are presented. An investigation of Schumacher and Hall's volume equation indicated that a better fit may be obtained by adding a constant to the dbh as predictor variable. The resultant equation is:

log V = ?4,2328 + 1,7154 log (D-2) + 1,1070 log H.  相似文献   
9.
Septoria represents a genus of plant pathogenic fungi with a wide geographic distribution, commonly associated with leaf spots and stem cankers of a broad range of plant hosts. A major aim of this study was to resolve the phylogenetic generic limits of Septoria, Stagonospora, and other related genera such as Sphaerulina, Phaeosphaeria and Phaeoseptoria using sequences of the the partial 28S nuclear ribosomal RNA and RPB2 genes of a large set of isolates. Based on these results Septoria is shown to be a distinct genus in the Mycosphaerellaceae, which has mycosphaerella-like sexual morphs. Several septoria-like species are now accommodated in Sphaerulina, a genus previously linked to this complex. Phaeosphaeria (based on P. oryzae) is shown to be congeneric with Phaeoseptoria (based on P. papayae), which is reduced to synonymy under the former. Depazea nodorum (causal agent of nodorum blotch of cereals) and Septoria avenae (causal agent of avenae blotch of barley and rye) are placed in a new genus, Parastagonospora, which is shown to be distinct from Stagonospora (based on S. paludosa) and Phaeosphaeria. Partial nucleotide sequence data for five gene loci, ITS, LSU, EF-1α, RPB2 and Btub were generated for all of these isolates. A total of 47 clades or genera were resolved, leading to the introduction of 14 new genera, 36 new species, and 19 new combinations.

Taxonomic novelties:

New genera - Acicuseptoria Quaedvlieg, Verkley & Crous, Cylindroseptoria Quaedvlieg, Verkley & Crous, Kirstenboschia Quaedvlieg, Verkley & Crous, Neoseptoria Quaedvlieg, Verkley & Crous, Neostagonospora Quaedvlieg, Verkley & Crous, Parastagonospora Quaedvlieg, Verkley & Crous, Polyphialoseptoria Quaedvlieg, R.W. Barreto, Verkley & Crous, Ruptoseptoria Quaedvlieg, Verkley & Crous, Septorioides Quaedvlieg, Verkley & Crous, Setoseptoria Quaedvlieg, Verkley & Crous, Stromatoseptoria Quaedvlieg, Verkley & Crous, Vrystaatia Quaedvlieg, W.J. Swart, Verkley & Crous, Xenobotryosphaeria Quaedvlieg, Verkley & Crous, Xenoseptoria Quaedvlieg, H.D. Shin, Verkley & Crous. New species - Acicuseptoria rumicis Quaedvlieg, Verkley & Crous, Caryophylloseptoria pseudolychnidis Quaedvlieg, H.D. Shin, Verkley & Crous, Coniothyrium sidae Quaedvlieg, Verkley, R.W. Barreto & Crous, Corynespora leucadendri Quaedvlieg, Verkley & Crous, Cylindroseptoria ceratoniae Quaedvlieg, Verkley & Crous, Cylindroseptoria pistaciae Quaedvlieg, Verkley & Crous, Kirstenboschia diospyri Quaedvlieg, Verkley & Crous, Neoseptoria caricis Quaedvlieg, Verkley & Crous, Neostagonospora caricis Quaedvlieg, Verkley & Crous, Neostagonospora elegiae Quaedvlieg, Verkley & Crous, Paraphoma dioscoreae Quaedvlieg, H.D. Shin, Verkley & Crous, Parastagonospora caricis Quaedvlieg, Verkley & Crous, Parastagonospora poae Quaedvlieg, Verkley & Crous, Phlyctema vincetoxici Quaedvlieg, Verkley & Crous, Polyphialoseptoria tabebuiae-serratifoliae Quaedvlieg, Alfenas & Crous, Polyphialoseptoria terminaliae Quaedvlieg, R.W. Barreto, Verkley & Crous, Pseudoseptoria collariana Quaedvlieg, Verkley & Crous, Pseudoseptoria obscura Quaedvlieg, Verkley & Crous, Sclerostagonospora phragmiticola Quaedvlieg, Verkley & Crous, Septoria cretae Quaedvlieg, Verkley & Crous, Septoria glycinicola Quaedvlieg, H.D. Shin, Verkley & Crous, Septoria oenanthicola Quaedvlieg, H.D. Shin, Verkley & Crous, Septoria pseudonapelli Quaedvlieg, H.D. Shin, Verkley & Crous, Setophoma chromolaenae Quaedvlieg, Verkley, R.W. Barreto & Crous, Setoseptoria phragmitis Quaedvlieg, Verkley & Crous, Sphaerulina amelanchier Quaedvlieg, Verkley & Crous, Sphaerulina pseudovirgaureae Quaedvlieg, Verkley & Crous, Sphaerulina viciae Quaedvlieg, H.D. Shin, Verkley & Crous, Stagonospora duoseptata Quaedvlieg, Verkley & Crous, Stagonospora perfecta Quaedvlieg, Verkley & Crous, Stagonospora pseudocaricis Quaedvlieg, Verkley, Gardiennet & Crous, Stagonospora pseudovitensis Quaedvlieg, Verkley & Crous, Stagonospora uniseptata Quaedvlieg, Verkley & Crous, Vrystaatia aloeicola Quaedvlieg, Verkley, W.J. Swart & Crous, Xenobotryosphaeria calamagrostidis Quaedvlieg, Verkley & Crous, Xenoseptoria neosaccardoi Quaedvlieg, H.D. Shin, Verkley & Crous. New combinations - Parastagonospora avenae (A.B. Frank) Quaedvlieg, Verkley & Crous, Parastagonospora nodorum (Berk.) Quaedvlieg, Verkley & Crous, Phaeosphaeria papayae (Speg.) Quaedvlieg, Verkley & Crous, Pseudocercospora domingensis (Petr. & Cif.) Quaedvlieg, Verkley & Crous, Ruptoseptoria unedonis (Roberge ex Desm.) Quaedvlieg, Verkley & Crous, Septorioides pini-thunbergii (S. Kaneko) Quaedvlieg, Verkley & Crous, Sphaerulina abeliceae (Hiray.) Quaedvlieg, Verkley & Crous, Sphaerulina azaleae (Voglino) Quaedvlieg, Verkley & Crous, Sphaerulina berberidis (Niessl) Quaedvlieg, Verkley & Crous, Sphaerulina betulae (Pass.) Quaedvlieg, Verkley & Crous, Sphaerulina cercidis (Fr.) Quaedvlieg, Verkley & Crous, Sphaerulina menispermi (Thüm.) Quaedvlieg, Verkley & Crous, Sphaerulina musiva (Peck) Quaedvlieg, Verkley & Crous, Sphaerulina oxyacanthae (Kunze & J.C. Schmidt) Quaedvlieg, Verkley & Crous, Sphaerulina patriniae (Miura) Quaedvlieg, Verkley & Crous, Sphaerulina populicola (Peck) Quaedvlieg, Verkley & Crous, Sphaerulina quercicola (Desm.) Quaedvlieg, Verkley & Crous, Sphaerulina rhabdoclinis (Butin) Quaedvlieg, Verkley & Crous, Stromatoseptoria castaneicola (Desm.) Quaedvlieg, Verkley & Crous. Typifications: Epitypifications - Phaeosphaeria oryzae I. Miyake, Phaeoseptoria papayae Speg.; Neotypification - Hendersonia paludosa Sacc. & Speg.Key words: Capnodiales, Multi-Locus Sequence Typing (MLST), Mycosphaerella, Mycosphaerellaceae, Phaeoseptoria, Phaeosphaeria, Phaeosphaeriaceae, Pleosporales, Septoria, Sphaerulina, Stagonospora, systematics  相似文献   
10.
Feed with Ammonium‐iron‐hexa‐cyanoferrate (AFCF; 1250 mg AFCF/kg) was fed between March 2009 and March 2011 to wild boars in a territory of 4.5 km2 (experimental group, EXP). One hundred and forty similar territories in the same county (500 km2, spruce forest, agriculture) served as control (CON). Data for comparison from all territories were available from March 2005 to March 2011. Wild boars could move between, into and from the territories. Lean skeletal muscle meat (500 g) of all wild boars that were killed by humans (hunting and traffic accidents) was investigated for gamma‐radiation from 137Cs with a becquerel monitor with a sodium iodide scintillator crystal (range of detection 20–9999 Bq/kg). The wild boars were weighed, and gender and age were determined. For the analyses of effects, multivariable regression models were fitted with the 137Cs concentration as response variable. There was a significant difference between the 137Cs contamination of wild boars from CON (563 ± 932 Bq/kg meat, n = 1253) and EXP (236 ± 276 Bq/kg meat; n = 45). 137Cs contamination decreased with increasing body weight by ?5 Bq/kg meat/kg body weight increase (p < 0.05). Females had higher Bq measurements than males (by +80 Bq/kg meat, p < 0.05). Piglets were lower than adults, but turn‐coats higher. From November to May, contamination was higher (by +500 to +600 Bq/kg meat, p < 0.05) than during the rest of the year. In 2010, contamination was higher (by +200 to + 300 Bq/kg meat, p < 0.05) in comparison with the other years under observation. When all covariates were controlled for, the effect of AFCF was highly significant. Interaction analyses showed that the intervention decreased 137Cs contamination by ?500 Bq/kg meat during November to May and by ?200 Bq/kg meat during the rest of the year. In summary, AFCF feeding reduces 137Cs contamination of wild boars living in the wild significantly, particularly during the season from November to May.  相似文献   
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