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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.

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.

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...

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.

The study was performed to declare the effects of temperature and relative humidity on the population density of Aphis nerii, and the parasitoids, Diaeretiella rapae and Aphidius sp. at two districts, Zagazig and Mansoura (Sharkia and Dakahlia Governorates, respectively) throughout two seasons, 2005-2006 and 2006-2007 on Difla plants. The results indicated a highly significant positive correlation between temperature and population density of A. nerii in the second seasons at the two districts, while relative humidity showed negative significant at Mansoura district in the last season. On the other hand, the data cleared highly significant correlation between temperature and D. rapae during the two seasons at the two districts. Results indicated a highly negative significant between temperature and Aphidius sp at Mansoura district during two seasons. A significant negative correlation was obtained between the two parasitoids, D. rapae & Aphidius sp and A. nerii during two seasons at two districts. The parasitoid, D. rapae accepted the stages of oleander aphid, A. nerii, with average number of mummies per female parasitoid 64.2. Results indicated insignificant effect on incubation period of eggs, larval and pupal durations between the two parasitoids, D. rapae and Aphidius sp., but the total developmental period of two parasitoids had a significant effect on A. nerii, the averages were 19.38±0.57 and 22.09±0.54 with D. rapae and Aphidius sp., respectively. The work showed that leaf -arrival time decreased with increasing host density. Meanwhile, the first sting-time, numbers of oviposition and mummies increased with increasing host density.

Se determinó el efecto de extractos de neem en el comportamiento de alimentación y la transmisión del Virus de la Mancha Anular del Papayo (PRSV-p) por Aphis nerii. Se evaluó un extracto acuoso al 10% de semillas de neem sin escarificar, y un testigo con agua, asperjados en plantas de papayo en el laboratorio. El comportamiento de alimentación del áfido se estudió en dos fases: exploratoria (0 hasta 3 min) y de alimentación (>3 hasta 20 min). Se determinó la mortalidad de áfidos a las 24 h. El análisis de la transmisión del virus se realizó con base en pruebas de ELISA. No se detectaron diferencias significativas (p > 0.05) en cuanto al comportamiento de alimentación para la fase exploratoria, lo que indica que el neem no afecta la búsqueda y el probado inicial del áfido sobre la planta. En cambio, un número significativamente mayor de áfidos (p < 0.05) dejó de alimentarse en la fase >3 hasta 20 min. Además, la mortalidad de áfidos es mayor (p < 0.05) en el tratamiento con plantas asperjadas con neem (37% vs. 10%). No se encontraron diferencias significativas (p > 0.05) en la transmisión del PRSV-p por Aphis nerii, lo que indica que los extractos acuosos de semillas de neem no impiden la transmisión del virus.

Non-Mendelian maternal effects, the effects of maternal phenotype or environment on offspring phenotype, have been documented in numerous taxa. By affecting offspring vital rates (birth, death, and movement), maternal effects have the potential to influence population dynamics. However, relatively few studies have directly linked maternal phenotype or environment to offspring vital rates. Additionally, even fewer studies have compared the magnitude of across-generation effects (i.e. maternal effects) to within-generation effects. 2. Because of their telescoping generations, aphids can be strongly influenced by maternal effects. The effects of maternal density and maternal host-plant species on offspring survival, fecundity, and alate formation were investigated experimentally in Aphis nerii , the milkweed - oleander aphid. 3. Additionally, the relative strength of maternal effects were compared with those operating within a generation. Therefore, in another set of experiments, the effects of current density and host-plant species (within-generation effects) on aphid vital rates were examined. 4. While maternal effects were present, within-generation effects were much stronger and more strongly influenced aphid vital rates. Within a generation, aphids exhibited density-dependent survival, fecundity, and alate formation and these effects varied among host-plant species. 5. These results indicate that while maternal effects have the potential to affect population dynamics, this potential is not always met. Additionally, the current environment, not the environment of previous generations, more strongly impacts population dynamics.

The objective of this work was to record the diversity of parasitoid of two aphid species, Brevicoryne brassicae L. and Aphis nerii Boyer de Fonscolombe in a site at Uberlândia, MG, and the relationship between parasitoid size and their mummies size, with reference to the host species. B. brassicae were collected on kale (Brassica oleracea L. var. acephala D.C.) and A nerii on milkweed (Asclepias curassavica L.). Samplings were made monthly from May, 1999 to May, 2000 in two experimental gardens. Morphometric measurements for both aphids and parasitoids were simplified by PCA analysis to achieve a multivariate size index. The parasitic Hymenoptera species associated with A. nerii were also found as parasitoids of B. brassicae, but with distinctive relative frequencies. Diaeretiella rapae (M'Intoch) (93.2%), Aphidius colemani Viereck (4.5%) and Lysiphlebus testaceipes (Cresson) (2.3%) were the parasitoids obtained from B. brassicae. Hyperparasitoids associated with these parasitoids were Alloxysta fuscicornis (Ashmead) (57.8%), Syrphophagus aphidivorus (Mayr) (25.1%) and Pachyneuron sp. (17.1%). The parasitoids found in A. nerii were: L. testaceipes (96.1%), A. colemani (3.9%) and the hyperparasitoids Pachyneuron sp. (85.2%) and S. aphidivorus (14.8%). Parasitoid size was correlated with mummy size for both A. nerii and B. brassicae. S. aphidivorus from A. nerii were significantly larger than those from B. brassicae. However, such differences were not detected for L. testaceipes, A. colemani or for Pachyneuron. Mummies of A. nerii were significantly larger than those of B. brassicae. No sexual dimorphism for size was detected.

Four species of aphid parasitoids, namely Aphidius colemani, Binodoxys angelicae, Lysiphlebus fabarum and Lysiphlebus testaceipes were reared from Aphis nerii on Nerium oleander and/or Stephanotis floribunda in Malta. Aphidius colemani was the most abundant, occurring in different habitat types. Binodoxys angelicae represents a confirmation of a doubtful past record, while Lysiphlebus testaceipes is a new record for Malta. Aphis nerii is evaluated as a refugium of several aphid parasitoids in Malta. Praon yomenae, another new record for Malta is also included in the present work., peer-reviewed

Es posible que exista tolerancia al virus de la mancha anular del papayo (PRSV-p) en plantas nativas de Carica papaya. Se evaluó la respuesta de 13 accesiones (Acc) de papayo nativo y la variedad Maradol roja respecto a la incidencia y severidad del PRSV-p, inoculado con el insecto vector Aphis nerii, y su relación con el manejo de la planta observado durante su colecta. Las Acc se colectaron en estado silvestre, en traspatio o cultivadas. A los tres meses de edad se inocularon las plantas con el virus. Se evaluó semanalmente la incidencia y severidad en nueve ocasiones. Las Acc 203 y 205 mostraron el menor índice de severidad (1.0), seguidas de 147a y 60 (con 1.7), 94a (2.0) y 197a (2.2); las Acc 64a (2.5) y 150 (2.8) alcanzaron una severidad intermedia, seguidas de la 65 y 210b (con 3.3), y de 80, 169 y 188a (con 4.3). La var. Maradol roja presentó el mayor índice de severidad (4.8). La severidad promedio en las Acc colectadas en manejo silvestre fue significativamente menor (P = 0.032) que en Maradol roja, aunque no fue diferente en las Acc que provenían de manejo de plantaciones cultivadas o de traspatio. Es posible que entre las Acc silvestres se encuentren genes de tolerancia al PRSV-p.

El afido de la adelfa, Aphis nerii Boyer de Fonscolombe, es una de las plagas mas comunes de plantas ornamentales en las familias Apocynaceae y Sclepiadaceae y tiene distribucion mundial, ha sido responsable de la mortalidad de un gran numero de arbustos de adelfa (Nerium oleander L.) cada ano. En este estudio se investigo la actividad insecticida de nanoparticulas de Ag contra A. nerii. Nanoparticulas de Ag y Ag-Zn fueron sintetizadas a traves de un metodo solvotermico, y con ellas se prepararon soluciones insecticidas de diferentes concentraciones y se probaron contra A. nerii. Con fines de comparacion, tambien se uso imidacloprid como un insecticida convencional. En los experimentos, el valor LC50 para imidacloprid, nanoparticulas de Ag y Ag-Zn se calculo como 0.13 μL mL-1, 424.67 mg mL-1, y 539.46 mg mL-1, respectivamente. El resultado mostro que nanoparticulas de Ag pueden ser usadas como una herramienta valiosa en programas de manejo de plagas de A. nerii. Adicionalmente, el estudio mostro que 1 μL mL1 imidacloprid y 700 mg mL-1 de nanoparticulas tuvieron el mayor efecto en mortalidad de los insectos.

キョウチクトウアブラムシの京都における生活環およびその天敵昆虫群構成を明らかにするため,京都市内2か所のキョウチクトウで1990年から3年間サンプリングおよび発生状況調査をおこない,次の結果を得た。1) キョウチクトウアブラムシは,京都において不完全生活環を全うできる。有翅虫は5月上旬に分散をはじめ,その後6月上旬,8月上旬,9月にそれぞれ発生のピークがみられた。秋にキョウチクトウが剪定され,新梢が伸長した場合にはその個体群は冬期にも高密度で推移したが,新梢が伸長しない場合には低密度で推移し,死滅することもあった。2月から3月の厳寒期には,胎生雌は増殖を停止し,その体色は鮮やかな黄色から乳濁色に変化した。越冬虫は3月末から増殖を再開し,4月末に最初の有翅虫が出現した。2) 本種の天敵昆虫として,次の15種を確認した。テントウムシ3種,ヒラタアブ4種,アブラコバエ1種,クサカゲロウ3種,ヒメカゲロウ1種,アブラバチ2種,ツヤコバチ1種。5月下旬から9月中旬までは,ダンダラテントウ(幼虫・成虫)の個体数が最も多く,その捕食が,アブラムシ個体群に対する重要な抑制要因であると考えられた。9月下旬以降はヒラタアブ(幼虫)や捕食寄生バチ類が活動したが,アブラムシの発生量を低下させることはできなかった。キョウチクトウアブラムシの毒性が,その天敵昆虫に及ぼす影響について考察した。