Photochemical isomerization of fluazifop-butyl

Fluazifop-butyl, butyl (RS)-2-[4-(5-trifluoromethyl-2-pyridyloxy)-phenoxy]propionate, as a thin film on glass, was photo-rearranged by ultraviolet irradiation at 254 nm to the isomer, butyl (RS)-2-[4-hydroxy-3-(5-trifluoromethyl-2-pyridyl)phenoxy]propionate. The reaction followed first-order kinetics. A mechanism that accounts for the formation of this product is proposed.     

Characterisation of Mycoplasma capricolum P60 surface lipoprotein and its evaluation in a recombinant ELISA

This paper reports the identification and characterisation of a 60kDa surface protein antigen (P60) of Mycoplasma capricolum subspecies capricolum (Mcc), and describes its diagnostic application. Genomic localization and presence in P60 of conserved functional domains suggested a structural and functional relationship with the immunodominant antigen P48 of Mycoplasma agalactiae, a basic membrane protein. A rP60-ELISA was developed, and it resulted in a high specificity for Mcc infections after evaluation with 125 goat sera. The comparison with an existent ELISA based on whole Mcc cell lysates showed that the two assays have comparable sensitivities, but the rP60-ELISA has the significant advantage of a greater specificity. Results indicate that P60 is a potential marker of Mcc infection, especially useful in areas where the presence of M. capricolum subspecies capripenumoniae is also reported.     

Current Status and Bottle Neck of Octopod Aquaculture: The Case of American Species

The increasing market demand for cephalopods and the experiences obtained with different species has boosted the interest in developing their culture in Latin America. In 2008, an international workshop was held in Puerto Montt, Chile, with 14 experts in experimental cephalopods aquaculture from Brazil, Chile, Spain, and Mexico. Several topics were approached within the holobenthic species Octopus maya and the merobenthic species Enteroctopus megalocyathus, Octopus vulgaris, and Robsonella fontaniana. Part of the conclusions demonstrated that the two greatest difficulties for their production were survival of paralarvae for merobenthic species, and survival of early juveniles for holobenthic species. Besides, there is a need to study the endogenous and exogenous factors affecting health and nutritional status of embryos, paralarvae, and juveniles. These stages, which may limit the culture, should be extensively studied in order to develop the appropriate environmental conditions and culture systems for the physiological and behavioral requirements, from egg incubation up to juveniles to reach a grow‐out phase.     

How to preserve horse chestnut trees from Cameraria ohridella in the urban environment

Control of Cameraria ohridella Deschka and Dimic (Lepidoptera: Gracillariidae), a pest on the horse chestnut tree (Aesculus hippocastanum L.) was tested using systemic injection in the 4-year period (2002–2005). Imidacloprid and abamectin were used with a single systemic tree injection treatment during May, immediately after blossom. A total of 77,760 leaves were sampled in the field to assess the effect on the number of mines caused by the horse chestnut leaf mining moth by comparing population levels in treated vs untreated trees. The mean number of mines per leaf ranged from 0 to 106.54.Both insecticides contained the pest, and their persistence was indicated by the level of effectives during the second year after treatment. The number of mines on the treated plants decreased significantly, and during the last year not more than three mines per leaf were observed, as against 64 mines on the control plants. Generally the infestation was reduced by up to 82%.Most of the holes in the bark of the treated plants were healed within 6–7 months from the treatment. Only in few trees extravasation of mucilaginous exudates or cracks on the trunk occurred.     

A set of standard area diagrams to assess severity of frogeye leaf spot on soybean

European Journal of Plant Pathology - A set of standard area diagrams (SADs) was developed and validated to aid visual assessment of severity of frogeye leaf spot (FLS) caused by Cercospora sojina....     

Diversity and pathogenicity of Colletotrichum species isolated from soursop in Colombia

Anthracnose, caused by Colletotrichum species is a highly limiting disease for the production of the tropical fruit tree crop, soursop (Annona muricata L.). In this study, 83 single-spore isolates of Colletotrichum were obtained from diseased soursoup tissues and subjected to a species complex-specific PCR assay. The isolates were identified as C. gloeosporioides sensu lato (n?=?60), C. boninense s. lat. (n?=?22), or C. acutatum s. lat. (n?=?1). A subset of 21 selected isolates was identified to species level by means of a multi-locus phylogenetic analysis using sequences from the ITS region and partial sequences of the actin, β-tubulin-2, glyceraldehyde-3-phosphate dehydrogenase, and chitin synthase-1 genes. The multi-locus phylogenetic analysis resolved C. theobromicola, C. tropicale, C. siamense, and C. gloeosporioides sensu stricto in the C. gloeosporioides complex; C. karstii and one undetermined species in the C. boninense complex; as well as one undetermined species in the C. acutatum complex. Significant differences in anthracnose severity were observed between Colletotrichum species when tested for pathogenicity on attached twigs of soursop cv. Elita. Colletotrichum theobromicola and C. tropicale were associated with high and intermediate virulence, respectively, whereas the remaining species were associated with low virulence.     

Occurrence of Groundnut ringspot virus on Brazilian peanut crops

A high incidence of plants with mosaic, chlorotic spots, ringspots, necrosis, smaller leaves, and stunting was observed on peanut crops (Arachis hypogaea L.) in Itápolis, São Paulo State, Brazil. Transmission electron microscope examination of thin sections of infected leaves revealed the presence of spheroidal particles, ca. 80 nm in diameter, suggestive of Tospovirus. A DNA fragment of ~600 bp was amplified by RT-PCR from total RNA extracted from infected tissues using primers specific for the nucleocapsid gene of Groundnut ringspot virus (GRSV). Nucleotide and deduced amino acid sequences of the fragments showed high identities with known GRSV isolates.     

Redox dysregulation and bioaccumulation of copper in tilapia Oreocromis niloticus

The objective of this study was to evaluate the effect of two concentrations of copper (0.13 and 0.5 mg L^?1) on juveniles of tilapia, Oreocromis niloticus (Linnaeus), using two toxicological assays (I‐ copper exposure and II‐ copper exposure followed by recovery). Doses were taken from the liver of the test organisms to determine the concentrations of copper, reduced glutathione, activities of glutathione S‐transferase and catalase, and lipid peroxidation. Exposure to copper in both assays resulted in significant accumulation of this metal in the analysed tissue and in decreased concentration of reduced glutathione. There was no alteration in the activities of catalase and glutathione S‐transferase and in lipid peroxidation.     

The ultrastructural evaluation of digestive cells in the hepatopancreas of the Amazon River prawn,Macrobrachium amazonicum

The Amazon River prawn Macrobrachium amazonicum is endemic to tropical South America and is being intensively exploited by artisanal fisheries in Brazil. Limited information is available about the nutritional requirements of M. amazonicum, although the production of this species is now technically feasible. The digestive process in this species is still unclear and investigation into the digestive cells of its hepatopancreatic epithelium is required. Thus, the hepatopancreas from 15 specimens were fixed in Karnovsky Solution and processed for Transmission Electron Microscopy. Our results indicate that E cells are located at the distal portion of the hepatopancreatic tubule and are involved in mitotic activity. The cylindrical R cells are sparse and are only found in the proximal portion of the hepatopancreatic tubule. According to its ultrastructural characteristics, this cell is involved in pinocytosis. M cells are generally found near the R cells. The F cells are scattered throughout the length of the hepatopancreatic tubules, and B cells are observed mainly in the proximal and middle regions. F cells and B cells are likely related to, respectively, the synthesis of enzymes and the intracelular digestion. R‐ and M cells are probably related to material storage. Thus, these findings provide basic information on the cell types that perform protein digestion in M. amazonicum, and will be useful in further nutritional research. The identification and characterization of digestive cells is an important step towards understanding the digestive mechanisms.