The Search Behavior of Omnivorous Thrips Larvae is Influenced by Spider Mite Cues

The western flower thrips is an omnivorous insect that consumes both leaf tissue and spider mite eggs. For this reason, these thrips are often described as ‘opportunistic predators’ of spider mites. Several studies have shown that western flower thrips are often found in association with spider mites, and the development time of thrips decreases and their survivorship increases when they consume spider mite eggs. We tested the hypothesis that thrips larvae may respond to chemical cues from spider mites, and that they may modify their prey-searching behavior when these spider mite-induced cues are present. We prepared hexane extracts from: 1) webbing of spider mites isolated from maize leaves, 2) webbing produced by spider mites inside an empty glass tube to exclude any plant-derived cues from the extract, and 3) spider mite cuticle extracts. These three extracts were subsequently applied in droplets to one-half of filter papers, and hexane alone was applied in droplets to the other half. We showed that residence time of thrips larvae was higher on filter paper with spider mite webbing extract, especially when the extract originated from spider mites isolated in glass tubes. In the presence of webbing extracts, we also observed: 1) a decrease in velocity, 2) an increase of angular velocity and 3) an increase in time immobile. Extracts from spider mite cuticle only increased velocity and proportion of time immobile of the thrips larvae. Our results suggest that chemical cues from spider mite webbing induce an arrestment response and play an important role in the non-random search behavior of thrips larvae searching for eggs on spider mite infested plant leaves

Interconfronto nazionale sul test di inibizione della bioluminescenza mediante Vibrio fisheri. National interlaboratory comparison study using Vibrio fisheri.

Nell\u2019ambito dei settori di applicazione ambientale dei saggi biologici la normativa nazionale prevede l\u2019impiego del test di inibizione della bioluminescenza del batterio marino Vibrio fischeri nelle attivit\ue0 di monitoraggio costiero condotto dalle Agenzie Regionali ai sensi della Legge 979/82 \u201cDifesa del Mare\u201d e facoltativamente dal D.Lgs. 152/06. Esso \ue8 inoltre ampiamente utilizzato nell\u2019ambito della caratterizzazione dei fondali marini prospicienti i Siti di bonifica di Interesse Nazionale ai sensi del DM 468/01. Sebbene attualmente siano disponibili numerosi protocolli ufficiali adottati da enti e/o organismi internazionali (DIN, 1992; Environment Canada, 2002, APAT IRSA-CNR, 2003), il percorso di standardizzazione ha visto in realt\ue0 una scarsa attenzione nei riguardi della valutazione della riproducibilit\ue0/ripetibilit\ue0 dei metodi previsti per ambienti marini e/o salmastri, come condizione indispensabile e precedente la normazione vera e propria. Gli unici esercizi di interconfronto noti interessano in realt\ue0 sostanze tossiche di riferimento e campioni di acqua dolce eseguiti nella soluzione standard a base di NaCl (APAT IRSA-CNR, 2003; Farr\ue9, 2004). Nell\u2019ambito del percorso di \u201cnormazione\u201d stabilito in seno alla Commissione UNICHIM \u201cMetodi Biologici\u201d, sottogruppo \u201cAcque marine e salmastre\u201d \ue8 stato organizzato un esercizio di interconfronto finalizzato alla valutazione della riproducibilit\ue0 e ripetibilit\ue0 di un metodo da applicare a matrici ambientali liquide marine

Effect of Diet on Development and Reproduction of Pezothrips kellyanus (Thysanoptera: Thripidae)

The developmental time, fecundity, and longevity of Pezothrips kellyanus (Bagnall) (Thysanoptera: Thripidae) encaged on lemon, Citrus limon (L.) Burm.f., leaves supplied with different food sources (pollen, sucrose, and honey) were compared at 25 degrees C. Only the addition of pollen offered a nutritional benefit for this thrips species. Pollen to the lemon leaf reduced total developmental time from egg to adult from 12.42 to 9.68 d, increased survival from 22.6 to 80.6%, and increased fecundity. When sugar was offered, only 10% of larvae survived. P. kellyanus larvae were unable to grow on lemon leaves as well as when honey was supplied to the leaves (recorded survival was 22.6 and 42.86%, respectively), and adult females were slightly able to reproduce (1.4 and 4.2 larvae per female, respectively). Pollen and honey supplements fed to adults double and triple adult longevity, respectively

Mission Beyond: The Acoustic Diagnostics Experiment on Board the International Space Station

Acoustic Diagnostics is an Italian Space Agency (ASI) biomedical experiment exploiting the diagnostic potential of otoacoustic emissions (OAEs) to monitor the astronauts’ hearing health on board the International Space Station (ISS). It is being performed (July 2019–April 2020) on the ISS, in the framework of the BEYOND mission, sponsored by European Space Agency (ESA). A dedicated instrument for measuring distortion product OAE (DPOAE) in a noisy environment was designed by University of Rome Tor Vergata and INAIL. Aerospace Logistics Technology Engineering Company (ALTEC) took care of the payload development, mechanical, thermal and electromagnetic tests, verification, and acceptance. Two astronauts were subjected, before leaving for their mission on the ISS, to the DPOAE test, along with a full set of audiological tests (Baseline Data Collection, BDC), especially designed at University of Roma La Sapienza and Campus Bio-Medico. An identical DPOAE apparatus was used five times on board the ISS to test the two astronauts. Finally, a post-flight BDC was performed, few days after return to Earth. Preliminary analysis demonstrated that the payload was able to record DPOAEs on board the ISS with very low instrumental noise level, despite the high noise level of the ISS environment. ASI, in the frame of its national mission of promoting and fostering the culture of space across the Country, provides access to the ISS as a laboratory in space. The utilization support services are provided, thanks to a contract, awarded by ASI, to ARGOTEC/ Telespazio (UTISS Team)

Effects of irrigation on the seasonal abundance of Empoasca vitis in north-italian vineyards.

The effect of irrigation on the abundance of Empoasca vitis (Go\ua8 the) populations was investigated in four vineyards located in northeastern Italy. In two experiments, we compared leafhopper population densities in plots irrigated (micro-spray irrigation system) or nonirrigated. In another experiment, we studied the effect of various irrigation systems on E. vitis populations over two successive seasons. In particular, eve treatments were compared: control (not irrigated), traditional drip system, three types of subirrigation varying in distance from the row (40, 135, and 95 cm). In this vineyard, stem water potential was monitored with a pressure chamber. E. vitis population densities were affected by irrigation, with higher densities of this pest recorded on irrigated vines. Highest E. vitis densities were detected in drip irrigation plots compared with nonirrigated plots where water stress was highest. Moderate water stress (subirrigation plots) was associated with intermediate leafhopper densities. Implications for integrated pest management are discussed