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121.
The red palm mite Raoiella indica Hirst (Tenuipalpidae) was first reported in the New World in 2004, dispersing quickly and widely while adopting new plant species as hosts. Since then, it has caused severe damage in this region, especially to coconut (Cocos nucifera L.). It was first found in Brazil in 2009, in the northern Amazonian state of Roraima. In the present study, native and introduced plants were sampled between March 2010 and February 2011 in sites of the 15 Roraima municipalities, to estimate its distribution and the associated mite fauna. In addition, monthly samples were taken from a coconut plantation in Mucajaí throughout the same period, for an initial appraisal of the levels R. indica could reach. It was found in 10 municipalities, on 19 plant species of four families. Six species are reported for the first time as hosts. Among the associated predators, 89.1% were Phytoseiidae, most commonly Amblyseius largoensis (Muma), Iphiseiodes zuluagai Denmark & Muma and Euseius concordis (Chant). The highest densities of R. indica, 1.5 and 0.35 mites/cm2 of leaflet (approx total of 331 and 77 mites/leaflet), were reached respectively in March 2010 and February 2011. The highest density of phytoseiids on coconut (0.009 mites/cm2 or about 2 mites/leaflet) was reached in November 2010. The average densities of R. indica recorded for Roraima were comparable to those reported for countries in which the mite is reportedly economically damaging. The dispersal of R. indica through the Amazon forest may result in damage to cultivated and native palms, and plants of other families, if the projected increase in both the frequency and the severity of drought events occurs. Parts of the Amazon have undergone periods of low rainfall, a condition that appears to favour the biology of this mite. Its eventual arrival to northeastern Brazil may result in heavy economic and ecological losses.  相似文献   
122.
The purpose of this study was to investigate whether sporulated Neospora caninum oocysts, which had been stored for 46 mo in a 2% sulfuric acid solution at 4 degrees C, remain morphologically viable and infective to gerbils (Meriones unguiculatus). Six gerbils were orally inoculated with doses of 400 or 1,200 oocysts. Two mo after inoculation, the animals did not show any clinical signs, had no histological lesions, and were seronegative for N. caninum at 1: 50 in an immunofluorescent antibody test. PCR using the brain from each gerbil did not reveal N. caninum specific DNA. We conclude that oocysts preserved for 46 mo are not infective, despite being morphologically intact.  相似文献   
123.
Interleukin 18 (IL-18) is a proinflammatory cytokine that plays a role in host defense by upregulating both innate and acquired immune responses. Analysis of IL18 polymorphisms may be clinically important since their roles have been recognized in a variety of inflammatory and autoimmune disorders. However, the role of this cytokine polymorphisms in kidney transplant still remains unclear. In this study, we evaluated the associations between IL18 polymorphisms and graft function assessed by creatinine clearance in kidney transplant recipients. A total of 82 kidney transplant recipients and 183 healthy controls were enrolled, and frequencies of alleles, genotypes and haplotypes for IL18 polymorphisms were determined and compared with creatinine clearance. The -607C/A (rs1946518) and -137C/G (rs187238) variant alleles in the IL18 gene were determined by polymerase chain reaction. In our study, no significant association was found between the IL18 variants and creatinine clearance (p > 0.05). Nonetheless, polymorphism analysis revealed an increase in the frequency of the IL18 major haplotype -607C/-137G in kidney transplant patients (odds ratio 2.57, 95% confidence interval 1.45–4.55, p = 0.0014). Finally, we found that IL18 polymorphisms did not influence the renal function and that IL18 haplotype -607C/-137G seems to be associated with kidney transplant recipients.  相似文献   
124.
125.

Background  

Biological knowledge is represented in scientific literature that often describes the function of genes/proteins (bioentities) in terms of their interactions (biointeractions). Such bioentities are often related to biological concepts of interest that are specific of a determined research field. Therefore, the study of the current literature about a selected topic deposited in public databases, facilitates the generation of novel hypotheses associating a set of bioentities to a common context.  相似文献   
126.
The present study investigated the potential of benzo-thiadiazole-7-carbothioic acid S -methyl ester (BTH) to protect postharvest melons var. 'Orange Flesh' from the fruit rot caused by Fusarium pallidoroseum . It was noticed that melon fruits immersed in BTH and postinoculated with the fungus presented the same pattern of disease incidence/severity and activity of the defence-related enzymes superoxide dismutase, ascorbate peroxidase, guaiacol peroxidase, phenylalanine ammonia-lyase, and β-1,3-glucanase of controls, indicating that BTH was ineffective in protecting melons from the fruit rot disease. However, the preflowering application of BTH in melon seedlings induced stunted growth, probably related to enhanced lignification which is related to the plant cell wall reinforcement and increase of resistance against invading pathogens, and alterations of the activity of the studied defence-related enzymes in comparison with controls, suggesting that this strategy could probably be effective for the control of the postharvest rot of melon fruits through activation of systemic resistance.  相似文献   
127.
128.

Many mite species disperse via the air. However, most methods described for the study of aerial dispersal have some limitations in the collection and/or recovery of mites that could be improved. The aim of this study was to describe a rotatory funnel-shaped collector that directs the wind to adhesive surfaces covered with a glycerin-based solution. Tests were conducted on a soccer field at UESC, Ilhéus, Brazil, in four 8-day periods. In total, 330 mites of 52 species of Eriophyidae, Tarsonemidae, Diptilomiopidae, Iolinidae, Triophtydeidae, Astigmata, Tydeidae, Phytoseiidae, Scutacaridae, Oribatida, Ascidae, Dolichocybidae, Eupodidae, Pygmephoridae and Tenuipalpidae were collected. Of the mites captured in the first three periods, 67% were Aceria sp. (Eriophyidae), and in the fourth period 46% were Coccotydaeolus aff. bakeri and Paurotyndareus sp. (Iolinidae). Comparisons between the funnel-shaped collector with the tube-shaped rotatable model of Duffner et al. (J Pest Sci 74:1–6, 2001, adapted from Schliesske 1977) showed that the former captured?>3× the number of mites and 2× the number of species. In conclusion, it is expected that the method described here could help in future pest management, and help solve ecological and behavioral problems involving airborne mite dispersal, offering a tool for monitoring, counting and identifying mites, or even other small arthropods, pollen and fungal spores, in experimental and applied studies.

  相似文献   
129.
The lipophorin of Rhodnius prolixus metabolically labelled with 32P exclusively in the phospholipid moiety was purified on a potassium bromide gradient and treated with phospholipase A2 in the presence of an excess of fatty acid-free albumin. The treatment completely removed the phospholipids from the particles and generated [32P]-lysophosphatidylcholine, [32P]-lysophosphatidylethanolamine, and free fatty acids that remained bound to albumin. The phospholipid-depleted lipophorin particles remained soluble, indicating that phospholipids are not essential in maintaining the stability of the particles in aqueous solution. Complete removal of phospholipids did not affect the association of apolipophorin III with lipophorin particles. Lipophorin density increased slightly from 1.120 to 1.134 g/ml after treatment. The phospholipid-depleted particles also retained their ability to be recognized and loaded in vitro with phospholipids delivered by the fat body, thus supporting the concept of lipophorin's role as a reusable lipid shuttle for phospholipids.  相似文献   
130.
The cultivation of tropical fruit trees has grown considerably in the state of Bahia, northeastern Brazil. Some of these have been severely attacked by phytophagous mites, which are usually controlled by the use of chemical pesticides. However, there is today a growing interest for the adoption of less aggressive measures of pest control, as for example the use of predatory mites. Most of the plant-inhabiting predatory mites belong to the family Phytoseiidae. The objective of this paper is to report the phytoseiid species found in an intensive survey conducted on cultivated tropical fruit trees in fifteen localities of the southern coast of Bahia. Measurements of relevant morphological characters are provided for each species, to complement the understanding of the morphological variation of these species. Twenty-nine species of sixteen genera were identified. A key was elaborated to assist in the separation of these species. Fifteen species are reported for the first time in the state, raising to sixty-six the number of species of this family now known from Bahia. Seventy-two percent of the species collected belong to Amblyseiinae, followed by Typhlodrominae (21%) and Phytoseiinae (7%). The most diverse genus was Amblyseius. Amblyseius operculatus De Leon was the most frequent and abundant species. Studies should be conducted to evaluate the possible role of the most common predators as control agents of the phytophagous mites co-occurring with them.  相似文献   
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