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Aphids are important sucking insects that attack many crops and cause huge economic loss. Essential oils have been proposed to be appropriate alternative to synthetic insecticides due to their low impact on environment and human health. In this work, the chemical compositions of eight essential oils extracted from plants growing in Egypt were determined by gas chromatography/mass spectrometry (GC–MS). The aphicidal activities of the isolated oils were examined against the adults of oleander aphid, Aphis nerii by a leaf-dipping assay. The inhibitory effect of essential oils on acetylcholinesterase (AChE) activity was also tested in vitro. Chemical analyses showed the essential oils consisted mainly of monoterpene hydrocarbons, oxygenated monoterpenes, sesquiterpene hydrocarbons and oxygenated sesquiterpenes except the oil of Artemisia monosperma which contained high content of benzenes. The results of toxicity assay showed that the oils of A. monosperma and Citrus sinensis were the most potent toxicants displaying LC50 value of 0.06 mg/L. The oils of Callistemon viminals, Schinus terebinthifolius and Schinus molle were also highly effective against aphid as their LC50 values were lower than 1 mg/L. In addition, the highest inhibitory effect on AChE was recorded by 0.5 mg/L C. sinensis with inhibition of 49.33%, while 0.1 mg/L Citrus lemon oil recorded the lowest inhibitory effect with inhibition of 0.4%. In general, six of tested essential oils showed high toxicity against A. nerii and they might be applied in the IPM programs for this insect.

La planta Asclepias curasavica L. es hospedera de la mariposa monarca (Danaus plexipus), allí su importancia; pero es atacado por el pulgón amarillo Aphis nerii. Las condiciones naturales de la zona de Satipo permiten la regulación natural de las plagas. Por ello, el objetivo fue estudiar el comportamiento de los depredadores y su efectividad de control del pulgón amarillo A. nerii en plantas de A. curasavica L. en condiciones de azotea de ciudad. Se ha trabajado con 10 plantas en macetero, los cuales fueron sembradas y desarrolladas en esas condiciones; se evaluó durante siete semanas en los meses de enero y febrero en época lluviosa. Se encontró que la población de pulgones A. nerii alcanza un pico de población a la quinta semana con 18,9 hojas por planta en promedio y decae a la sexta semana para desaparecer a la séptima semana por efecto de control biológico natural. Se ha encontrado cuatro especies de insectos depredadores: Cheilomenes sexmaculata, que presenta mayor población que el resto de depredadores; seguido de la mosca Ocyptamus sp., luego Scymnus sp. y finalmente Cycloneda sanguínea en menor proporción en larvas por planta. El más efectivo es C. sexmaculata; mientras que C. sanguínea y la mosca Ocyptamus sp. muestran un nivel intermedio. Scymnus sp. es menos efectivo por el tamaño pequeño del insecto. C. sexmaculata logra eliminar al pulgón en la séptima semana; mientras que las otras especies crecen solo hasta la cuarta y quinta semana, luego desaparecen a falta de alimento.

Predatory efficiency of Eupoedes corollae predator's larvae toward densities of 25, 50, 75, 100 insect of Aphis gossypii and of Aphis nerii, a study was carried out of the laboratory in growth chamber with a temperature of 24±1 C◦ and 70 ± 10 % RH and photoperiod 12: 12 hours. The results showed that the predator E. corollae larvae consumption in different percentage according to the prey's species and the number provided, and that 50 density of cotton aphid was the best in the daily and total consumption of E.corollae predator, in addition to the relatively low development period of predator larvae at the same density. The average of consumption of the predator's larvae instars was proportional to the different densities of the aphids 25, 50.75 and 100 insect, as it reached to ( 84.64, 143.16, 170.9 and 217.93) of cotton aphid and (56.23, 110.67, 124.78 and 148.16) insects of oleander aphid , respectively. The average of aphid is estimated at 154.2 and 110.2 insect, respectively, for the two species with significant differences between them.

This paper presents the first record of the oleander aphid (Aphis nerii Boyer de Fonscolombe, 1841; Hemiptera: Aphididae) in Slovakia, and also one of the most northern record of this natural pest on the invasive common milkweed (Asclepias syriaca Linnaeus.; Apocynaceae) in Central Europe. Modern social media crowdsourcing has achieved comprehensive distribution data in the horticultural community, and a total of 35 new distribution sites were discovered in 28 Slovak settlements, one new site in Austria, and one in the Czech Republic. It was further established that the oleander aphid could survive in anthropogenic refuges during the winter months.

In this study the possibility of using liquidInula viscosa(Dittrichia viscosa L.) to improve the growth and quality ofOscularia deltoidesandCorpuscolaria lehmaniiplants and protection againstAphis neriiwas evaluated. The 3 experimental groups in cultivation were: i) group without the use ofInula viscosaliquid macerate (CTRL), irrigated with water and previously fertilised substrate; ii) group treated with 1% ofInula viscosaliquid obtained from flowers (leaf spraying and soil irrigation), previously fertilized substrate (INU1); iii) group treated with 1% ofInula viscosaliquid obtained from leaves and stems (leaf spraying and soil irrigation), previously fertilized substrate (INU2). The test showed a significant increase in the agronomic parameters analyzed in plants treated with liquidInula viscosa. In fact, all plants treated with Inula showed a significant increase in plant height, leaves number, vegetative and roots weight, branches and flowers number and flowering time in bothCorpuscolaria lehmaniiandOscularia deltoides. An evaluation was also made of the number of individuals ofAphis neriipresent on the plants ofCorpuscolaria lehmaniiandOscularia deltoidesto assess whether the macerate of Inula can be used for the control of these insects. The GC-MS analysis of active fractions strongly suggested costic acid as the compound responsible for contact toxicity againstAphis nerii. Probably in the plant treated withInula viscosathere is an induction of the defense mechanisms that lead to greater resistance to biotic and abiotic stresses. The application of Inula macerate also improves the plant's defences against attacks by fungal pathogens and insects. Very interesting aspects, especially in view of a possible reduction of fertilizers and synthetic plant protection products.

Gymnema sylvestre, a perennial woody climber popular for its antidiabetic property and its leaves are widely recommended to use in the traditional system of medicine. The oleander aphid, Aphis nerii is a major pest of G. sylvestre from October to March in central India. The present study was carried out to evaluate the efficacy of different biorational insecticides like Azadiractin 1% EC (10000ppm), aqueous leaf extract (5%) of Kalmegh or the Creat, King of Bitters (Andrographis paniculata) and Indian bael or Golden apple (Aegle marmelos), insect growth regulator (Buprofezin 25% SC), commercial entomopathogenic formulations like Beauveria bassiana (2×109 spores/ml), Metarhizium anisopliae (2×109 spores/ml), Lecanicillium muscarium (Verticillium lecanii; 2×109 spores/ml) on A. nerii under laboratory and field condition during 2019 and 2020. It was discovered that the leaf spray method was superior to the leaf dipping method. In the leaf spray method, hundred percent mortality of A. nerii was recorded with the application of azadirachtin post 72 HAT and efficacy of B. bassiana, M. anisopliae and L. muscarium were statistically in the same group during both year of study. However, in the leaf dip method, hundred percent mortality of A. nerii was recorded with the treatment of azadirachtin post 96 HAR. In both bioassay methods, the lowest population reduction and mortality were observed in bael followed by kalmegh plant extract under laboratory conditions. On the tenth days of treatment, azadirachtin showed hundred percent reduction in the aphid population with hundred percent efficacy. The entomopathogenic fungi like M. anisopliae (85.4%, 87.8%) and B. bassiana (78.3%, 83.8%) were equally effective in reducing A. nerii population with the efficacy of (87.4%, 90.4%) and (81.2%, 87.2%) under field condition during 2019 and 2020 respectively.

Aphids are excellent experimental models for a variety of biological questions ranging from the evolution of symbioses and the development of polyphenisms to questions surrounding insect's interactions with their host plants. Genomic resources are available for several aphid species, and with advances in the next-generation sequencing, transcriptomic studies are being extended to non-model organisms that lack genomes. Furthermore, aphid cultures can be collected from the field and reared in the laboratory for the use in organismal and molecular experiments to bridge the gap between ecological and genetic studies. Last, many aphids can be maintained in the laboratory on their preferred host plants in perpetual, parthenogenic life cycles allowing for comparisons of asexually reproducing genotypes. Aphis nerii, the milkweed-oleander aphid, provides one such model to study insect interactions with toxic plants using both organismal and molecular experiments. Methods for the generation and maintenance of the plant and aphid cultures in the greenhouse and laboratory, DNA and RNA extractions, microsatellite analysis, de novo transcriptome assembly and annotation, transcriptome differential expression analysis, and qPCR verification of differentially expressed genes are outlined and discussed here.

The insecticidal activity of four natural products based on soaps prepared from plant oils (sunflower and olive) against Aphis nerii Boyer de Fonscolombe and Macrosiphum rosae (L.) was evaluated in vitro. It was found that SLGEL1521OLT, SLUN and OLGEL manifested the strongest insecticidal activity against both aphids. A higher efficacy was observed towards M. rosae, as compared with A. nerii. The number of surviving individuals was recorded after 24h. The efficacy was estimated by means of the Henderson and Tilton formula (1955) and the results were statistically analyzed with the R language for statistical computing (R Development Core Team, 2011) and the drc R language package.

Aphids and thrips are very important pest species of many greenhouse and field plants in the world. In recent years, there have been attempts to identify plants for their insecticidal property with a view to find out suitable alternatives to the indiscriminate use of chemical pesticides, which are a risk for human health and the environment. The aim of this work was to evaluate the insecticidal effect of Eucalyptus globulus Labill essential oil (EO) against Aphis nerll Boyer de Fonscolombe (Hemiptera: Aphididae) and Gynaikothrips ficorum Marchal (Thysanoptera: Ploeothridae). The EO was extracted by hydrodistillation and the bioassay was evaluated by toxicity contact method, using solutions at different concentrations and for different time intervals. The EO was more toxic to G. ficorum (LC50 = 0.031pL cm-2) than A. nerll(LC50 = 0.099pL cm-2) on filter discs at 12 h of exposure. These results suggested that EO from E. globulus constitute a good alternative for the control of A. nerll and G. ficorum, considering their insecticidal effects at low applied concentrations and for short periods of time. Los áfidos y trips son dos de las más importantes especies de plagas que Invaden Invernaderos y cultivos en el mundo. En los últimos años se han realizado muchos esfuerzos con el propósito de identificar plantas por sus propiedades insecticidas, como una alternativa al uso indiscriminado de insecticidas químicos que constituyen un riesgo para la salud humana y el medioambiente. El objetivo de este trabajo fue evaluar el efecto insecticida del aceite esencial (AE) de Eucalyptus globulus Labill sobre Aphis nerii Boyer de Fonscolombe (Hemiptera: Aphididae) y Gynaikothrips ficorum Marchal (Thysanoptera: Ploeothridae). El AE se extrajo por hidrodestilación y los bioensayos se evaluaron usando el método de toxicidad por contacto a diferentes concentraciones e intervalos de tiempo. Estudios exploratorios se realizaron previamente para determinar las concentraciones apropiadas de testeo. El AE fue más tóxico sobre G. ficorum (LC50 = 0.031|uL cm-2) que sobre A. nerii(LC50 = 0.099|uL cm-2) en el ensayo realizado en discos de papel de filtro correspondiente a las 12 h de exposición. Estos resultados sugieren que el AE de E. globulus constituye una buena alternativa para el control de A. nerii y G. ficorum considerando el efecto insecticida a bajas concentraciones y cortos tiempos de exposición.

Laboratory and semi- field experiments were carried out during 2013 winter season at Sharkia region to evaluate the performance of the parasitoid species Diaeretiella rapae (M'Intosh)for controlling Brevicoryne brassicae L., Aphis craccivora (Koch) and Aphis nerii Boyer infesting cabbage, faba bean and oleander plants. With the increase of parasitoid density, the percentage of parasitism increased to reach a maximum of 35.7, 29.7 and 25.2% for D. rapae at 11 parasitoid/200 aphids per jar in laboratory and a minimum of 11.30, 7.30 and 5.90% at one parasitoid per jar. Meanwhile, the highest percentage of parasitism were 92.20, 83.20 and 79.30% for D. rapae at 20 parasitoids/200aphids per cage in semi-field test, a minimum of 61.80, 48.70 and 41.50% recorded at five parasitoids per cage on B. brassicae, A. craccivora and A. nerii, respectively. On the other hand, with the increase of parasitoid density the percentage of emerged adults decreased to reach a maximum of 80.93, 75.54 and 63.85% for D. rapae at one parasitoid per jar in laboratory and 77.80, 73.56 and 57.90% at five parasitoids per cage in the field on B. brassicae, A. craccivora and A. nerii, respectively. With the increase of parasitoid density the fecundity of the parasitoid D. rapae increased (as number of mummies and emerged adults increased). The maximum numbers of mummies in the field were 185.60, 166.4 and 158.6 for D. rapae at 20 parasitoids per cage and minimum of 124.60, 97.40 and 83.0 mummies at five adults per cage. It is concluded that the parasitoid D. rapae could have the potential to be suitable biological control agent against B. brassicae, A. craccivora and A. nerii. Key words: Diaeretiella rapae, Brevicoryne brassicae, Aphis craccivora, Aphis nerii, Release, Density.

The oleander aphid, Aphis nerii Boyer de Fonscolombe, feeds on members of the Apocynaceae family. In Kentucky, A. nerii colonizes several Asclepias species and Cynanchum laeve. The prevalence of milkweeds and A. nerii in Kentucky ecosystems allow natural enemies, including the primary parasitoid Lysiphlebus testaceipes, to utilize this aphid as a resource. The efficacy of L. testaceipes when utilizing A. nerii reared on different host plant species was studied in the field and in the laboratory. In the laboratory, the time until first host contact and the number of ovipositional attempts by L. testaceipes did not vary among aphids from different host plant species. However significantly more aphids were mummified and more parasitoids successfully emerged from aphids on C. laeve than from aphids on tested Asclepias species. The successful emergence rates of L. testaceipes from A. nerii colonizing four species of milkweed were also determined in a naturally infested field plot. While no significant...

In a survey that was conducted during the year 2011, a local strain of Aphid lethal paralysis virus (ALPV) was identified and isolated from a wild population of Aphis nerii aphids living on Nerium oleander plants located in northern Israel. The new strain was tentatively named (ALPV-An). RNA extracted from the viral particles allowed the amplification and determination of the complete genome sequence. The virus genome is comprised of 9835 nucleotides. In a BLAST search analysis, the ALPV-An sequence showed 89 % nucleotide sequence identity with the whole genome of a South African ALPV and 96 and 94 % amino acid sequence identity with the ORF1 and ORF2 of that strain, respectively. In preliminary experiments, spray-applied, purified ALPV virions were highly pathogenic to the green peach aphid Myzus persicae; 95 % mortality was recorded 4 days post-infection. These preliminary results demonstrate the potential of ALPV for use as a biologic agent for some aphid control. Surprisingly, no visible ALPV pathogenic effects, such as morphological changes or paralysis, were observed in the A. nerii aphids infected with ALPV-An. The absence of clear ALPV symptoms in A. nerii led to the formulation of two hypotheses, which were partially examined in this study. The first hypothesis suggest that A. nerii is resistant or tolerant of ALPV, while the second hypothesis propose that ALPV-An may be a mild strain of ALPV. Currently, our results is in favor with the first hypothesis since ALPV-An is cryptic in A. nerii aphids and can be lethal for M. persicae aphids.

A detailed karyotype analysis of the oleander aphid Aphis nerii focusing on the distribution, molecular composition and epigenetic modifications of heterochromatin was done in order to better understand the structure and evolution of holocentric/holokinetic chromosomes in aphids. The female karyotype (2n = 8) consisted of 3 pairs of autosomes and a pair of X chromosomes that were the longest elements in the karyotype and carried a single, terminally located nucleolar organizer region. Males showed 2n = 7 chromosomes due to the presence of a single X chromosome. Heterochromatin was located in the X chromosomes only and consisted of 4 satellite DNAs that have been identified. A. nerii constitutive heterochromatin was enriched in mono-, di- and tri-methylated H3 histones and HP1 proteins but, interestingly, it lacked DNA methylation that was widespread in euchromatic chromosomal regions. These results suggest that aphid heterochromatin is assembled and condensed without any involvement of DNA methylation.