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1.
Summary On two occasions an anaplasm was isolated from sheep on the Dutch island of Ameland. The organism proved to be highly pathogenic for splenectomised sheep; a non-splenectomised animal recovered spontaneously after the packed cell volume had decreased by 40%. Treatment with oxytetracycline was effective. Its pathogenicity for goats appeared to be low, and the organism was apparently not infective to splenectomised cattle. This anaplasm differs from Anaplasma ovis in that less than 30% of the organisms are marginally situated in the red cell, as against over 70% in A. ovis; cross-immunity with A. ovis was incomplete and the latter appeared to be far more pathogenic to goats than the Dutch anaplasm, for which the name Anaplasma mesaeterum sp.n. is proposed. Its ultrastructure is similar to that of A. marginale and A. ovis. The vector is either Ixodes ricinus or Haemaphysalis punctata. Its practical importance remains to be ascertained. 相似文献
2.
Fortes Maira Salomão Lopes-Mori Fabiana Maria Ruiz Caldart Eloiza Teles Constantino Caroline Evers Fernanda Pagliari Sthefany de Almeida Jonatas Campos Barros Luiz Daniel Freire Roberta Lemos Garcia João Luis Headley Selwyn Arlington Navarro Italmar Teodorico 《Tropical animal health and production》2018,50(2):413-419
Tropical Animal Health and Production - This study investigated the prevalence of caprine toxoplasmosis in goat herds from Southern Brazil by the indirect immunofluorescence assay (IFA), and... 相似文献
3.
Andrés F. Sánchez-Restrepo Nadia L. Jiménez Viviana A. Confalonieri Luis A. Calcaterra 《国际虫害防治杂志》2019,65(3):244-257
AbstractLeaf-cutting ants (LCA) are considered one of the main herbivores and one of the most destructive pest insects of the Neotropics. Northeastern Argentina harbors the greatest species richness of these ants and in turn comprises the highest surface with forest plantations. Our aim was to establish which species of leaf-cutting ants are most commonly associated with forest plantations by analyzing their geographic distribution using published and unpublished species occurrence data. Also, estimate their potential areas of distribution along a latitudinal gradient that entirely encompasses northeastern Argentina using Ecological Niche Modeling. Only seven of the 20 species recorded were strongly associated with productive systems along the gradient, but only 2–3 species in each region could be considered high-risk species for forest plantations. High-risk species composition shows a turnover between regions. Our models show the potential distribution areas where LCA could become more abundant and dominant, and possibly causing a detrimental effect on the forest plantations in the studied region. We find that ecological niche models are useful tools to assess the environmental suitability of important LCA. 相似文献
4.
Francisco A Macías Nuria Chinchilla Elena Arroyo Rosa M Varela José MG Molinillo David Marín 《Pest management science》2010,66(10):1137-1147
BACKGROUND: Fifteen novel derivatives of D‐DIBOA, including aromatic ring modifications and the addition of side chains in positions C‐2 and N‐4, had previously been synthesised and their phytotoxicity on standard target species (STS) evaluated. This strategy combined steric, electronic, solubility and lipophilicity requirements to achieve the maximum phytotoxic activity. An evaluation of the bioactivity of these compounds on the systems Oryza sativa–Echinochloa crus‐galli and Triticum aestivum–Avena fatua is reported here. RESULTS: All compounds showed inhibition profiles on the two species Echinochloa crus‐galli (L.) Beauv. and Avena fatua L. The most marked effects were caused by 6F‐4Pr‐D‐DIBOA, 6F‐4Val‐D‐DIBOA, 6Cl‐4Pr‐D‐DIBOA and 6Cl‐4Val‐D‐DIBOA. The IC50 values for the systems Echinochloa crus‐galli–Oryza sativa and Avena fatua–Triticum aestivum for all compounds were compared. The compound that showed the greatest selectivity for the system Echinochloa crus‐galli–Oryza sativa was 8Cl‐4Pr‐D‐DIBOA, which was 15 times more selective than the commercial herbicide propanil (Cotanil‐35). With regard to the system Avena fatua–Triticum aestivum, the compounds that showed the highest selectivities were 8Cl‐4Val‐D‐DIBOA and 6F‐4Pr‐D‐DIBOA. The results obtained for 6F‐4Pr‐D‐DIBOA are of great interest because of the high phytotoxicity to Avena fatua (IC50 = 6 µM , r2 = 0.9616). CONCLUSION: The in vitro phytotoxicity profiles and selectivities shown by the compounds described here make them candidates for higher‐level studies. 8Cl‐4Pr‐D‐DIBOA for the system Echinochloa crus‐galli‐Oryza sativa and 6F‐4Pr‐D‐DIBOA for Avena fatua‐Triticum aestivum were the most interesting compounds. Copyright © 2010 Society of Chemical Industry 相似文献
5.
Ana M. Casas Carlota R. Gazulla Arantxa Monteagudo Carlos P. Cantalapiedra Marian Moralejo M. Pilar Gracia Francisco J. Ciudad William T.B. Thomas José L. Molina-Cano Scott Boden Bruno Contreras-Moreira Ernesto Igartua 《作物学报(英文版)》2021,(4):862-872
Response to vernalization and photoperiod are the main determinants controlling the time to flowering in temperate cereals. While the individual genes that dete... 相似文献
6.
7.
Gregoria Pulgar Gemma Víllora Joaquin Hernández Nicolas Castilla Luis Romero 《Journal of plant nutrition》2013,36(6):719-730
Chinese cabbage plants [Brassica pekinensis (Lour) Rupr. cv. Nagaoka 50] were cultivated experimentally for two years (1993 and 1994) using a semi‐forcing technique of floating rowcovers, polyethylene (T1), polypropylene (T2), versus no floating row‐covers, control (T0). Five samplings were made, taking four plants per each replication and total phosphorus (P) (Ptotal), inorganic P (Pi), and calculated organic P (Porg) were determined as well as foliar acid phosphatase activity (FAPA). The aerial and root temperatures of the treatments T1 and T2 exceeded those of T0. The Ptotal concentration showed no significant variations with treatment, whereas the Pi concentrations increased in Ti and T2 and Porg decreased in both treatments with respect to T0. The FAPA was influenced a similar way as Pi, raising with temperature. The contents (mg plant‐1) of Ptolal, Pi, and Porg were greater in T1 and T2 than in T0, and this could be due to the fact that the highest temperatures (root and aerial zone) generated by the plastic rowcovers favored the absorption of P, thereby boosting FAPA and the fresh and dry weights, and yield. 相似文献
8.
Guillermo Carrillo-Castañeda Juana Juárez Muñoz José R. Peralta-Videa Eduardo Gomez Jorge L. Gardea-Torresdey 《Journal of plant nutrition》2013,36(10):1853-1865
Microbes have developed high-affinity uptake mechanisms to assimilate iron (Fe) and other metals such as aluminum (Al), gallium (Ga), chromium (Cr), and copper (Cu). Siderophores, which are metal chelating compounds, and membrane receptor proteins are involved in these specialized mechanisms. A few siderophore-producing microorganisms associated with plant roots also influence the uptake of some metals. In this study, the potential microbial-assisted Cu and Fe uptake by Phaseolus vulgaris (common bean) plants was evaluated. Seedlings of cultivated common bean varieties Bayo-INIFAP (B) and Negro-150 (N) and wild types yellowish (WY) and black (WB) were developed in the presence of a Cu and Fe solution and associated with the siderophore-producing microorganisms R. leguminosarumbv. Phaseoli (strains 19, 44, and 46); Pseudomonas fluorescens(strain Avm), and Azospirillum brasilense (strain 154). Seedlings of cultivated variety N and black wild type WB inoculated with the strain CPMex.44 accumulated 71% and 30% more Fe than the un-inoculated plants, respectively; however, the wild black bean accumulated the highest absolute amount of Fe (221.56 mg/kg of dry matter) as compared with the cultivated black variety N (126.16 mg/kg of dry matter) (P < 0.05). In the wild type WY seedlings, the highest Fe accumulation was observed when the seeds were inoculated with the Pseudomonas strain Avm (206 mg/kg of dry matter) (P < 0.05). The interaction of Pseudomonas strain Avm with seedlings of the cultivated B variety and the wild type WB promoted the highest accumulation of Cu (51 and 54 mg/kg of dry matter, respectively), 7 and 14 mg more than in the respective non-inoculated seedlings. No promotion of Fe accumulation was observed in the seedlings of the cultivated B variety and in roots; instead, less Fe was accumulated. The wild type WY did not show any improvement in Cu accumulation. In this study, Rhizobiumstrains promoted Fe but not Cu uptake in P. vulgaris seedlings while Pseudomonas strains promoted the uptake of both Cu and Fe. 相似文献
9.
Macedo ML Damico DC Freire Md Toyama MH Marangoni S Novello JC 《Journal of agricultural and food chemistry》2003,51(10):2980-2986
This study describes the purification of an N-acetylglucosamine-binding lectin from Koelreuteria paniculata seeds and its effects on the larval development of Callobruchus maculatus and Anagasta kuehniella. The lectin (KpLec) was characterized and isolated by gel filtration, affinity column, and reverse phase chromatography. SDS-PAGE indicated that this lectin is a dimer composed of subunits of 22 and 44 kDa. The N terminus exhibited 40% similarity with Urtiga dioica agglutinin. KpLec was tested for anti-insect activity against C. maculatus and A. kuehniella. With regard to C. maculatus, an artificial diet containing 0.7 and 1% KpLec produced LD(50) and ED(50) value, respectively. However, for A. kuenhiella, an artificial diet containing 0.65% KpLec produced an LD(50), whereas 0.2% KpLec produced an ED(50). The transformation of genes coding for this lectin could be useful in the development of insect resistance in important agricultural crops. 相似文献
10.
Salas JH González MM Noa M Pérez NA Díaz G Gutiérrez R Zazueta H Osuna I 《Journal of agricultural and food chemistry》2003,51(15):4468-4471
A study was conducted to measure residues of 13 organophosphorus (OP) pesticides, widely used as dairy cattle ectoparasiticides or in crops used for animal feed, in homogenized and pasteurized Mexican milk samples. Four different milk brands with high distribution were collected biweekly during a 12 month period (n = 96) in supermarkets. OP pesticide residues were measured by gas chromatography with a flame photometric detector. Approximately 39.6% of the samples contained detectable levels of OP pesticide residues. Eight samples contained residues exceeding established maximum residue limits (MRL), and the OP pesticides present in these samples were dichlorvos (five samples), phorate, chlorpyrifos, and chlorfenvinphos (one sample, respectively). Average residues of 13 OP pesticides measured were below established MRLs ranging between 0.0051 and 0.0203 ppm. 相似文献