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91.
Vítor Gabriel Ambrosini Daniel José Rosa Alex Basso Marcelo Borghezan Rosete Pescador Alcione Miotto 《Journal of plant nutrition》2017,40(3):404-416
This study aimed to assess the effect of liming as an ameliorator of copper (Cu) toxicity in black oats (Avena strigosa Schreb.) grown in soil with a sandy texture. The treatments were soil supplementation with increasing doses of lime (0.0, 0.5 and 1.0 g kg?1) and two of Cu (0 and 50 mg kg?1). Pre-germinated black oat seeds were sown for 30 days in the soil, subsequently, the plant height, root and shoot dry mass and concentration of total chlorophyll, chlorophylls a and b, carotenoids and total soluble carbohydrates and starch were analyzed. The dose of 50 mg kg?1 soil Cu caused a toxic effect on black oat plant growth and development, affected the internal distribution of nutrients, decreased the leaf chlorophyll concentration and increased the leaf concentration of total soluble carbohydrates and starch. Increasing lime doses ameliorated the toxic effects of Cu. 相似文献
92.
Campbell PM Reiner D Moore AE Lee RY Epstein MM Higgins TJ 《Journal of agricultural and food chemistry》2011,59(11):6047-6054
The seeds of peas (Pisum sativum) and chickpeas (Cicer arietinum) expressing a gene for α-amylase inhibitor-1 (αAI) from the common bean (Phaseolus vulgaris) are protected from damage by old world bruchids (pea and cowpea weevils). Here, we used electrospray ionization time-of-flight mass spectrometry to compare the post-translational modifications of αAI from transgenic sources with the processed forms of the protein from several bean varieties. All sources showed microheterogeneity with differences in the relative abundance of particular variants due to differences in the frequency of addition of glycans, variable processing of glycans, and differences of C-terminal exopeptidase activity. The structural variation among the transgenics was generally within the range of the bean varieties. Previously, mice showed allergic reactions following ingestion of transgenic pea αAI but not bean αAI. Here, only minor differences were observed following intraperitoneal sensitization. Both of the transgenic pea and bean forms of αAI elicited Th1 and Th2 antibody isotype responses, suggesting that both proteins are immunogenic and could potentially be allergenic. 相似文献
93.
Devesa V Loos A Súñer MA Vélez D Feria A Martínez A Montoro R Sanz Y 《Journal of agricultural and food chemistry》2005,53(26):10297-10305
A study of the transformation of arsenic species by the microflora of the freshwater crayfish Procambarus clarkii was carried out. The study of the degradation of AB (arsenobetaine) was performed in aerobic conditions in two culture media (tryptic soy broth and saline medium) at two temperatures (30 and 8 degrees C). The microflora transformed AB into TMAO (trimethylarsine oxide), DMA (dimethylarsinate), MA (methylarsonate), and an unidentified compound (U1). The quickest transformations were carried out by microflora from hepatopancreas incubated in saline medium at 30 degrees C. The individualized study of other arsenic species [AC (arsenocholine), TETRA (tetramethylarsonium ion), TMAO, DMA, and MA] was also performed in saline medium. The only transformation observed was of AC into AB. The bacteria possibly responsible for AB degradation were isolated, identified by phenotypic and genotypic methods, and individually assayed for AB transformation. Only isolates allocated to the species Pseudomonas putida were able to metabolize AB. 相似文献
94.
95.
Sharon L Deem Andrew J Noss Rosa Leny Cuéllar William B Karesh 《Journal of zoo and wildlife medicine》2005,36(4):598-605
Bolivia has a total of 47 species of Psittacidae, seven of which have been identified in our study site, the semiarid Gran Chaco of the Isoso. One species, the blue-fronted parrot (Amazona aestiva), is frequently captured by local Isose?o Guaraní Indians for exploitation on the national and international market. These birds are often temporarily housed in small villages under unhygienic conditions with poultry and other domestic species. On occasion, these parrots escape back to the wild. Additionally, many of these birds are kept as pets or are used to lure wild. parrots within slingshot range for subsequent capture. In this study, we evaluated the health status, including the level of exposure to selected infectious agents, in the wild-caught captive birds and free-ranging birds. Physical examinations were performed, and blood was collected, from 54 live birds (20 captive and 34 free-ranging). Feces were collected from 15 birds (seven captive and eight free-ranging). Necropsies were also performed on four recently dead wild-caught birds. On serologic testing, no birds were found to have antibodies to avian influenza virus, Chlamydophila psittaci, infectious bronchitis virus, infectious bursal disease virus, infectious laryngotracheitis virus, Marek's disease virus, paramyxovirus-1, paramyxovirus-2, paramyxovirus-3, polyomavirus, eastern equine encephalitis virus, western equine encephalitis virus, or Venezuelan equine encephalitis virus. Positive antibody titers were found for psittacine herpesvirus (8/44, 18.2%), Aspergillus spp. (3/51, 5.9%), and Salmonella pullorum (33/49, 67.3%). All three of the birds that tested antibody positive for Aspergillus spp. were captive, whereas six of the eight and 15 of the 33 birds that tested positive for psittacine herpesvirus and S. pullorum, respectively, were wild. 相似文献
96.
Ardanuy Agns Figueras Mart Matas Montserrat Arn Judit Agust Nuria Alomar scar Albajes Ramon Gabarra Rosa 《Journal of pest science》2022,95(1):447-459
Journal of Pest Science - Conservation biological control involves manipulation of the environment to enhance the effectiveness of natural enemies in controlling crop pests. In this study, we... 相似文献
97.
Phylogenetic position and nucleotide diversity of Fusarium oxysporum f. sp. vanillae worldwide based on translation elongation factor 1α sequences
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F. R. Flores‐de la Rosa E. De Luna J. Adame‐García L. G. Iglesias‐Andreu M. Luna‐Rodríguez 《Plant pathology》2018,67(6):1278-1285
Fusarium oxysporum f. sp. vanillae is considered the most important fungus affecting vanilla crops around the world, causing rot on vanilla roots and stems. Previous studies showed that the ability to infect vanilla plants is a polyphyletic trait among strains of the Fusarium oxysporum species complex (FOSC). The same studies proposed a single origin for F. oxysporum f. sp. vanillae isolates sampled from Mexico, the centre of origin and distribution of vanilla. The aim of this work was to test the hypothesis of the monophyletic origin of a wider sample of isolates of F. oxysporum f. sp. vanillae infecting Mexican vanilla and estimate nucleotide diversity of pathogen isolates from the main vanilla‐producing countries. Sequence data for the TEF1α gene from 106 isolates was assembled. The phylogenetic analyses suggest that some Mexican isolates of F. oxysporum f. sp. vanillae belong in two well‐supported clades, mixed with isolates from Madagascar, Indonesia, Réunion and Comoros. The phylogenetic position of other Indonesian and Mexican isolates is unresolved. Estimations of nucleotide diversity showed that the population from Mexico is genetically more diverse than the other three populations from Madagascar, Indonesia and Réunion. The results support a polyphyletic origin of vanilla‐infecting isolates of F. oxysporum worldwide, and also reject the proposition that Mexican isolates have a single origin. The phylogenetic optimizations over the strict consensus tree of the ability to infect vanilla plants suggest that pathogenic strains around the world are the product of multiple shifts of pathogenesis and dispersion events. 相似文献
98.
Bedenice D Bar-Yishay E Ingenito EP Tsai L Mazan MR Hoffman AM 《American journal of veterinary research》2004,65(9):1259-1264
OBJECTIVE: To evaluate the use of a modified whole body plethysmograph in awake sheep. ANIMALS: 10 healthy adult sheep. PROCEDURE: Concurrent measurements of specific airway resistance (sR(aw)) and pulmonary resistance (R(L)) were obtained using a novel noninvasive head-out constant-volume plethysmograph and esophageal balloon-pneumotachography, respectively. All data were collected before and after external resistive loading with 1 and 5.6 cm H2O/L/s. Functional residual capacity (FRC) was measured by helium dilution for computation of airway resistance (R(aw)) preloading (R(aw) = sR(aw)/FRC). RESULTS: The sR(aw) and R(L) were closely correlated in 10 adult sheep. Additionally, sR(aw), and R(L) accurately reflected the magnitude of added resistance. The mean FRC was 52 mL/kg and used to calculate R(aw). At baseline, the values for R(aw) were significantly correlated with sR(aw) and R(L). CONCLUSIONS AND CLINICAL RELEVANCE: Precise measurements of sR(aw) and R(aw) at baseline and sR(aw) after external resistive loading were obtained by use of this novel noninvasive plethysmographic technology. This method should have application to veterinary patients or animals used in research in which noninvasive rapid or serial measurements of sR(aw) in the conscious state are required. 相似文献
99.
100.
Helga Pülzl Daniela Kleinschmit Bas Arts 《Scandinavian Journal of Forest Research》2014,29(4):386-393
The term bioeconomy and closely related notions like bio-based economy or knowledge-based bioeconomy (KBBE) are increasingly used by scientists and politicians in the last years. It does therefore have the potential of becoming an influential global discourse. Its role is however so far unclear. The general assumption that guides this paper is that discourses, resulting ideas and arguments are generally said to have performative power. They shape actors' views, influence their behaviour, impact on their beliefs and interests and can cause institutional change in a given society. Thus, the aim of this paper is twofold: first, it aims to analyse whether the ideas used in a bioeconomy discourse differs from those in other global meta-discourses of the last decades affecting forest discourses, such as the ecological modernization discourse or the sustainable development discourse. Second, this paper aims to analyse whether and how the bioeconomy discourse has started (or not) to reshape or overshadow the “classical” forest discourses, such as sustainable forest management, forest biodiversity or forest and climate change. 相似文献