Acute toxicity in laboratory tests of fresh and aged residues of pesticides used in citrus on the parasitoid Aphytis melinus

Parasitoids are the main natural enemies of the California red scale, Aonidiella aurantii (Maskell) and on occasion can regulate their populations. To increase their effectiveness, inoculative or augmentative releases of parasitoids are promoted. Previous to the implementation of any release strategy an important and necessary step is to acquire knowledge on the parasitoid fauna associated with this key phytophagous pest. Parasitoids were surveyed and quantified in Spanish citrus orchards between 2005 and 2009. Aphytis melinus DeBach (87.1%) resulted as the dominant species, followed by Aphytis chrysomphali (Mercet) (15.9%), Encarsia perniciosi (Tower) (2.4%) and Aphycus hederaceus (Westwood) (0.004%). Overall, higher levels of parasitism were recorded in fruit than in twigs. Scales in fruit were parasitized at similar levels by the different parasitoid species whereas E. perniciosi was more active in twigs. Data eventually reveal the recent displacement of A. chrysomphali by A. melinus. The implications of these results on the biological control of A. aurantii are discussed and this information will be useful in the decision of IPM strategies for this pest.

Section: Discussionmentioning

confidence: 99%

Displacement of Aphytis chrysomphali by Aphytis melinus, parasitoids of the California red scale, in the Iberian Peninsula

Boyero

Vela

Wong

et al. 2014

“…Among these factors, one arises, the response of the exotic parasitoid to the portfolio of available pesticides for each crop. The assessment of acute toxicity of pesticides constitute a corner stone for CBC programmes within and IPM programme, as the degree of toxicity of a pesticide could reduce the establishment and survival of non-target arthropods (Jerraya, 2003;Suma et al, 2009;Urbaneja et al, 2009;Biondi et al, 2012aBiondi et al, , 2013Biondi et al, , 2015Juan-Blasco et al, 2013;Vanaclocha et al, 2013).…”

Section: Introductionmentioning

confidence: 99%

Residual toxicity of insecticides used in Tunisian citrus orchards on the imported parasitoid Diachasmimorpha longicaudata (Hymenoptera: Braconidae): Implications for IPM program of Ceratitis capitata (Diptera: Tephritidae)

Harbi

Abbes

Sabater-Muñoz

et al. 2017

Citrus agro-industry is globally harshened mainly by Ceratitis capitata (Wiedemann), the most worldwide destructive tephritid fruit fly species. Citrus agro-industry is one of the pillars of Tunisia economy, and by hence, harshened by this species. Tunisia has established an Integrated Pest Management (IPM) programme against citrus pests, including C. capitata, that rely on the structured use of pesticides, on the application several trapping protocols, along with pilot-scale sterile insect technique program and, since 2013, with pilot-scale releases of the braconid parasitoid Diachasmimorpha longicaudata Ashmed (Hymenoptera: Braconidae). Insecticide sideeffects on parasitoids and other natural enemies are being requested for a successful implementation of biological control within any IPM programme. However, these data are almost scarce for the braconid species D. longicaudata. To this end, we have determined the side-effects of malathion, methidathion, acetamiprid, azadiractin, abamectin, deltametrin+thiacloprid and spinosad, as the most popular insecticides used in Tunisia either as fresh residues or at several aged time points, on the parasitoid D. longicaudata according the IOBC pesticide harm-classification. IOBC classification evolution of residues over time had allowed determining the best combination of pesticide applications in a structured fashion with the viable releases of D. longicaudata for the control of C. capitata in Tunisian citrus agro-ecosystems.

“…Because of the importance of citrus as a crop, there are many studies that have determined the side effects of pesticides on parasitoids that are key natural enemies of citrus pests Prabhaker et al, 2007Prabhaker et al, , 2011Suma et al, 2009;Vanaclocha et al, 2012). Continuous evaluation of new products allows the creation of data banks with the side effects of pesticides on natural enemies, as it happens with citrus (Jacas & Urbaneja, 2010;IVIA, 2012), which are of great importance to IPM implementation.…”

Section: Introductionmentioning

confidence: 99%

Side effects of different pesticides used in citrus on the adult stage of the parasitoid Aphytis melinus DeBach (Hymenoptera Aphelinidae) and its progeny

González-Zamora

Castillo

Avilla

2013

Twelve pesticides commonly used in citrus in Spain were tested on adults of Aphytis melinus DeBach to determine their effects on parasitoid survival and fecundity, and the duration of the residue of each pesticide. Six of these pesticides were found to be harmless to moderately harmful to this parasitoid in a laboratory assay in closed Petri dishes: spinosad (bait formulation), azadirachtin, fenbutatin, fosetyl-Al, copper oxichloride, and mancozeb, with their scores on the reduction of beneficial capacity (RBC) index being between 21.4 and 94.6% after one week. The other six pesticides classified as harmful were tested on citrus plants to study their persistence over time under greenhouse conditions: Pirimicarb, pyriproxifen, paraffinic oil, abamectin, chlorpyrifos, and lambda-cyhalothrin. Most of these products reduced their negative effect on adults of A. melinus between one and six weeks after treatment, although lambda-cyhalothrin was still harmful to parasitoids 11 weeks after application. This information can help growers and consultants to make decisions about pesticide selection and application timing in citrus in order to support IPM implementation when A. melinus is present.