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BACKGROUND Insecticide-treated nets (ITNs) have been investigated recently for their use in agriculture. Depending on the insecticide, the hole size and the way they are produced, these nets can target different pests and therefore they could be interesting options for use in integrated pest management (IPM). As the information on their compatibility with beneficial fauna is practically negligible, in this work we have tested the compatibility of an experimental bifenthrin long-lasting insecticide-treated net (LLITN) with Amblyseius swirskii and Eretmocerus mundus, important natural enemies of whiteflies and thrips, under laboratory, semi-field and commercial greenhouse conditions. RESULTS In the laboratory, the treated net was very deleterious to adults of both natural enemies, after 72 h exposure. However, in choice tests with Y-tubes, both natural enemies were neither attracted nor repelled by the treated net and no short-term mortality was detected in individuals that had crossed it. No deleterious effects on the E. mundus beneficial capacity were detected in semi-field trials. In field trials, the LLITN proved to be compatible with A. swirskii while decreasing pest densities. CONCLUSIONS Bifenthrin LLITN studied could be a valuable method for reducing pest population infestations in IPM programmes while being compatible with biocontrol agents. © 2017 Society of Chemical Industry [ABSTRACT FROM AUTHOR]

The toxicity of spinosad and methoxyfenozide against neonates and fourth instars of Spodoptera littoralis (Boisduval) (Lepidoptera: Noctuidae) was tested under laboratory conditions. According to LC50 values, no significant differences were observed between spinosad (0.50 mg [AI]/kg diet) and methoxyfenozide (0.54 mg [AI]/kg diet) after 48 h of ingestion treatment on neonate larvae, based on the overlap of 95% CU Similarly, on fourth instars, no significant differences were observed between LC50 (2.98 and 5.17 mg [AI]/kg diet for spinosad and methoxyfenozide, respectively, at 96 h after ingestion of artificial diet) and LD50 (4.74 and 2.68 μg [AI]/g larva for spinosad and methoxyfenozide, respectively, at 144 h after topical application). In addition, spinosad and methoxyfenozide significantly suppressed weight gain of neonates and fourth instars continuously fed with artificial diet containing the insecticides. The second part of this project was focused on the effects of methoxyfenozide on the reproduction of S. littoralis by determining the effect on oviposition in three different crosses and the pharmacokinetics pattern of (14C)-methoxyfenozide in the body tissues of female and male adults after topical application in their excrement and in the deposited eggs to test transport through the female and the male adult. Methoxyfenozide negatively affected the reproduction of adults regardless the treated sex, presumably because of its presence in the adult body, accumulation in the laid eggs, and slow excretion of the product. We conclude that spinosad and methoxyfenozide represent an important choice to be used in integrated pest management where S. littoralis is a major pest. [ABSTRACT FROM AUTHOR]

Methoxyfenozide (RH-2485) was found to be 7.5-fold less toxic in terms of LD[sub50] values against last-instar larvae of a greenhouse-selected strain of the beet armyworm Spodoptera exigua (Hübner) that was collected in July 2001 in an experimental greenhouse for resistance at Murcia in southern Spain, in comparison with a laboratory susceptible strain. To date, the compound is the newest member of this new group of moulting hormone accelerating IGRs to reach the marketplace against Lepidoptera. To understand this different potency in the greenhouse-selected S exigua, oxidative metabolism and acetylcholinesterase activities were measured in last-instar larvae and adults. In addition, we determined, by the use of [sup14]C-labelled rnethoxyfenozide, the pattern of absorption in body tissues and excretion via faeces in last-instar larvae of the greenhouse-selected strain and compared the results with those from the laboratory susceptible strain. It was striking that the rate of excretion was about twice as high in the greenhouse-selected strain, resulting in a more rapid clearance of insecticide amounts from the insect body. Data are discussed in relation to mechanisms of lower toxicities for this new group of IGRs. [ABSTRACT FROM AUTHOR]

Three novel insecticides, pyriproxyfen, spinosad and tebufenozide, were evaluated for their effect on survival and reproduction of Chrysoperla carnea adults using two methods of exposure: direct contact and ingestion. Pyriproxyfen and tebufenozide proved to be harmless to adult survival, whereas spinosad 72 h after treatment reduced the number of adults by 39.8% and 87.2% in topical and ingestion treatment at the maximum concentration recommended (800 mg a.i. litre[sup-1]). Fecundity was not affected irrespective of the insecticide or time of application (before or after the onset of oviposition). Concerning fertility, only pyriproxyfen exerted a negative effect on hatching when the eggs were deposited by females treated by ingestion in the post-oviposition period at the highest concentration tested (150 mg a.i. litre[sup-1]). [ABSTRACT FROM AUTHOR]

The article highlights the survey of the Trogoderma species of the family Dermestidae which are considered as important pests of stored products. Topics include the existence of various strict quarantine legislation to prevent the introduction of the pest, the impact of global warming and increased international trade on their expansion and the restricted distribution of the species in Spain.

Introduction: Listeria monocytogenes is the third most common cause of community-acquired bacterial meningitis in adults., Aims: To describe the characteristics of meningitis caused by Listeria (LM) in adults and to compare them with those of meningitis due to other causations (nLM)., Patients and Methods: A retrospective analysis of a series of hospital cases was conducted, including patients aged between ≥ 14 years diagnosed with LM in a referral hospital between 1982 and 2011., Results: The study involves 16 cases of LM, 12.1% of the cases of community-acquired meningitis with an identified aetiology. Predisposing factors were age (mean of 65 versus 52 years; p = 0.019) and immunosuppression/comorbidity (62.5% versus 3.4%; p < 0.001), treatment with corticoids (37.5%) and chronic liver disease (25%) being the most frequent. The classical triads of acute bacterial meningitis, clinical features and analysis of the cerebrospinal fluid (CSF) were observed in 50 and 75% of the cases, respectively. Patients with LM presented lower leukocyte counts in CSF, a lower percentage of neutrophils, a greater frequency of lymphocytic pleocytosis and a lower frequency of Gram stain positive than those with nLM. The mortality rate was 12.5%, similar to that of patients with nLM., Conclusions: LM mainly affects patients who are immunosuppressed or with comorbidity, as well as elderly patients, although it may occur in the absence of risk factors. Clinically it does not differ from other causes of meningitis, but the initial CSF study may suggest it. Its mortality rate is similar to that of meningitis due to other aetiologies.

Introduction: Gram-negative bacilli are causative agents of bacterial meningitis in the neonatal period but rarely cause meningitis in adults without risk factors., Aim: To report on meningitis due to gram-negative bacilli (MGNB) in adults diagnosed in a hospital over a 25-year period., Patients and Methods: We reviewed the medical records of all patients with an age > or = 14 years who had been diagnosed with MGNB between 1982 and 2006., Results: Fifteen cases of MGNB are included (10.5% of the cases of bacterial meningitis with an identified aetiology), with a mean age of 48 years (14-79). Twelve (80%) were post-operative: recent neurosurgery (9 cases, 75%) and having a neurosurgical device (8 cases, 67%) were risk factors. Three (20%) were spontaneous: two were of a urinary origin and one had an undetermined origin. The aetiology was: Pseudomonas aeruginosa (3 cases), Escherichia coli (3 cases), Enterobacter aerogenes (2 cases), Pseudomonas fluorescens (1 case), Klebsiella pneumoniae (1 case), Morganella morganii (1 case), Acinetobacter anitratus (1 case), Acinetobacter iwoffii (1 case) and Flavobacterium brevis (1 case); in one patient with Gram positive staining for gram-negative bacilli, the culture was negative, and three of them (20%) were mixed infections (Staphylococcus spp.). Three patients (20%) died., Conclusions: In adults, gram-negative bacilli rarely cause spontaneous meningitis, but are a common causation of post-neurosurgical meningitis and in those with neurosurgical devices. The mortality rate of MGNB is high.