Attraction of Chrysotropia ciliata (Neuroptera, Chrysopidae) Males to P-Anisaldehyde, a Compound with Presumed Pheromone Function

In a field-trapping experiment with plant volatiles, we observed notably high attraction of green lacewing (Chrysotropia ciliata) males to the compound p-anisaldehyde. Based on this finding, we initiated the present study to elucidate this phenomenon and to investigate the chemical ecology ofC. ciliata.Scanning electron microscopy revealed elliptical glands abundantly distributed on the 2nd to 6th abdominal sternites ofC. ciliatamales, whereas females of the species completely lacked such glands. No p-anisaldehyde was found in extractions of body parts ofC. ciliata.Methyl p-anisate and p-methoxybenzoic acid were identified exclusively in the extract from abdominal segments 2-8 of males. Field-trapping experiments revealed no attraction ofC. ciliatato either methyl p-anisate or p-methoxybenzoic acid. In contrast, males showed marked attraction to p-anisaldehyde in the field and antennae showed strong responses to this compound. Headspace collections in the field from living insects in their natural environment and during their main daily activity period indicated that p-anisaldehyde was emitted exclusively byC. ciliatamales. Our overall results suggest that p-anisaldehyde might serve as a male-produced pheromone that attracts conspecificC. ciliatamales. Here, we discuss hypotheses regarding possible mechanisms involved in regulation of p-anisaldehyde production, including involvement of the compounds methyl p-anisate and p-methoxybenzoic acid, and the potential ecological function of p-anisaldehyde inC. ciliata

Aula de innovación educativa

El artículo forma parte de un monográfico dedicado a sinergias en torno a la lectura.- Resumen tomado parcialmente de la revista.Análisis de dos aspectos importantes en el proceso de la lectura estrechamente relacionados con las destrezas del lector y con el resultado de su proceso de compresión, más concretamente, con la destreza metacognitiva de control de la comprensión y las destrezas cognitivas implicadas en la tarea del resumen. Concluye con algunas sugerencias sobre cómo desarrollar estas habilidades para formar lectores competentes..CataluñaConsejería de Educación, Formación y Empleo. Servicio de Publicaciones y Estadística; Avda.la Fama, 15; 30006 Murcia; +34 968279685; +34 968279835; [email protected]

The Ratio between Field Attractive and Background Volatiles Encodes Host-Plant Recognition in a Specialist Moth

Volatiles emitted by plants convey an array of information through different trophic levels. Animals such as host-seeking herbivores encounter plumes with filaments from both host and non-host plants. While studies showed a behavioral effect of non-host plants on herbivore host location, less information is available on how a searching insect herbivore perceives and flies upwind to a host-plant odor plume within a background of non-host volatiles. We hypothesized here that herbivorous insects in search of a host-plant can discriminate plumes of host and non-host plants and that the taxonomic relatedness of the non-host have an effect on finding the host. We also predicted that the ratio between certain plant volatiles is cognized as host-plant recognition cue by a receiver herbivorous insect. To verify these hypotheses we measured the wind tunnel response of the moth Argyresthia conjugella to the host plant rowan, to non-host plants taxonomically related (Rosaceae, apple and pear) or unrelated to the host (Pinaceae, spruce) and to binary combination of host and non-host plants. Volatiles were collected from all plant combinations and delivered to the test insect via an ultrasonic sprayer as an artificial plume. While the response to the rowan as a plant was not affected by the addition of any of the non-host plants, the attraction to the corresponding sprayed headspace decreased when pear or apple but not spruce were added to rowan. A similar result was measured toward the odor exiting a jar where freshly cut plant material of apple or pear or spruce was intermixed with rowan. Dose-response gas-chromatography coupled to electroantennography revealed the presence of seven field attractive and seven background non-attractive antennally active compounds. Although the abundance of field attractive and of some background volatiles decreased in all dual combinations in comparison with rowan alone, an increased amount of the background compounds (3E)-4,8-Dimethyl-1,3,7-nonatriene ((E)-DMNT) and (Z)-3-hexenyl acetate was found in the rowan-apple and rowan-pear but not in the rowan-spruce headspace. A higher ratio between the abundance of each field attractive component and that of (E)-DMNT and (Z)-3-hexenyl acetate was measured for rowan and rowan-spruce in contrast to rowan-pear and rowan-apple headspaces. Our result suggests that the ratio between field attractive and background antennaly active volatiles encodes host-plant recognition in our study system

Kairomone‐assisted trap cropping for protecting spring oilseed rape ( Brassica napus

BACKGROUND Pollen beetles are key pests in oilseed rape (OSR) production. These beetles use visual and olfactory cues to locate their host plants at specific phenological stages, hence trap cropping may represent an alternative pest control strategy. In this study, a trap crop strategy for spring OSR was developed. To elaborate such a trap cropping system, a pest control measure that eradicates the attracted beetles in the trap crop before they migrate further into the main crop was included in the final trap cropping strategy. RESULTS Testing yellow‐flowering turnip rape and one yellow‐ and two cream‐coloured flowering OSR cultivars as potential crops in different trap cropping strategies, we found that pollen beetles clearly preferred turnip rape over the cream‐coloured and yellow OSR cultivars, and preferred the yellow OSR cultivar over the two cream‐coloured cultivars. This behaviour was related to the plant growth stage and associated volatile and colour signals of the tested cultivars. Using turnip rape as a trap crop and testing kairomone‐ or insecticide‐assisted trap cropping as the pest control strategy was as effective as compared with whole fields treated with a standard pesticide. CONCLUSION Combining a turnip rape cultivar as trap crop with kairomone traps placed in the trap crop as a killing agent may enable renunciation of pesticides in spring OSR production. © 2020 Society of Chemical IndustrypublishedVersio

Retention and distribution of pesticides in planted filter microcosms designed for treatment of agricultural surface runoff

Pesticides in agricultural surface water runoff cause a major threat to freshwater systems. Installation of filter systems or constructed wetlands in areas of preferential run-off is a possible measure for pesticides abatement. To develop such systems, combinations of filter materials suitable for retention of both hydrophilic and hydrophobic organic pesticides were tested for pesticide removal in planted microcosms. The retention of six pesticides frequently detected in surface waters (bentazone, MCPA, metalaxyl, propiconazole, pencycuron, and imidacloprid) was evaluated in unplanted and planted pot experiments with novel bed material mixtures consisting of pumice, vermiculite, water super-absorbent polymer (SAP) for retention of ionic and water soluble pesticides, and synthetic hydrophobic wool for adsorption of hydrophobic pesticides. The novel materials were compared to soil with high organic matter content. The highest retention of the pesticides was observed in the soil, with a considerable translocation of pesticides into the plants, and low leaching potential, in particular for the hydrophobic compounds. However, due to the high retention of pesticides in soil, environmental risks related to their long term mobilization cannot be excluded. Mixtures of pumice and vermiculite with SAP resulted in high retention of i) water and ii) both hydrophilic and hydrophobic pesticides but with much lower leaching potential compared to the mineral systems without SAP. Mixtures of such materials may provide near natural treatment options in riparian strips and also for treatment of rainwater runoff without the need for water containment systems.publishedVersio

Retention and distribution of pesticides in planted filter microcosms designed for treatment of agricultural surface runoff

Pesticides in agricultural surface water runoff cause a major threat to freshwater systems. Installation of filter systems or constructed wetlands in areas of preferential run-off is a possible measure for pesticides abatement. To develop such systems, combinations of filter materials suitable for retention of both hydrophilic and hydrophobic organic pesticides were tested for pesticide removal in planted microcosms. The retention of six pesticides frequently detected in surface waters (bentazone, MCPA, metalaxyl, propiconazole, pencycuron, and imidacloprid) was evaluated in unplanted and planted pot experiments with novel bed material mixtures consisting of pumice, vermiculite, water super-absorbent polymer (SAP) for retention of ionic and water soluble pesticides, and synthetic hydrophobic wool for adsorption of hydrophobic pesticides. The novel materials were compared to soil with high organic matter content. The highest retention of the pesticides was observed in the soil, with a considerable translocation of pesticides into the plants, and low leaching potential, in particular for the hydrophobic compounds. However, due to the high retention of pesticides in soil, environmental risks related to their long term mobilization cannot be excluded. Mixtures of pumice and vermiculite with SAP resulted in high retention of i) water and ii) both hydrophilic and hydrophobic pesticides but with much lower leaching potential compared to the mineral systems without SAP. Mixtures of such materials may provide near natural treatment options in riparian strips and also for treatment of rainwater runoff without the need for water containment systems