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Photo-selective nets (PSN) are used to manipulate the physiology of fruit crops. Besides their advantages to the crop, PSN potentially affect insect pests and their natural enemies. We aimed to assess the effects of these production systems on the searching behavior of the codling moth parasitoid, Mastrus ridens. We hypothesized that PSN and black standard nets (SN) affect the behavior of the parasitoid by delaying host localization and reducing parasitism. Laboratory experiments were carried out in closed cages under four treatment conditions: black SN, pearl PSN, red PSN, and no PSN as control (uncovered cages). Our results showed that the host localization of M. ridens was delayed under black SN and enhanced by pearl and red PSN. The PSN and the black SN did not affect the parasitism levels. In addition, the initial behavior of the parasitoid during the first 30 min of the bioassays was not affected by treatments. However, females spent most of the time walking around the arena, grooming, or resting, regardless of the color of the net. Parasitism was not affected under the PSN or the black SN, however, this must be verified in field conditions.

Background Enterohepatic species of the genus Helicobacter (EHH) are emerging pathogens that have been associated with gastrointestinal and hepatobiliary diseases in humans. However, studies on their pathogenicity are scarce. Galleria mellonella is a recently proposed model for the study of virulence in different pathogens, such as Campylobacter spp. and Helicobacter pylori. Despite this, its usefulness in EHH has not yet been evaluated. Therefore, we determined the pathogenic potential of different EHH species isolated from dogs in this infection model. Materials and methods Four species of EHH (H. bilis, H. canicola, H. canis, and 'H. winghamensis') isolated from fecal samples from domestic dogs were evaluated. Three strains of each species were inoculated in cohorts of G. mellonella at a concentration of 1 × 107 CFU/mL. Survival curves were determined by the Kaplan-Meier method. In addition, the quantification of melanin, bacterial load in hemolymph, and histopathology were evaluated daily post-infection (pi). Results G. mellonella larvae are susceptible to EHH infection, exhibiting intra- and inter-species variability. Melanin production became evident from 4 h pi and increased throughout the assay. All species were recovered from the hemolymph after 20 min pi; however, only H. canis could be recovered up to 48 h pi. Histopathology revealed cellular and humoral immune response, evidencing accumulation of hemocytes, nodulation, and melanin deposition in different tissues. Conclusion EHH species carried by dogs have considerable pathogenic potential, being H. canicola the species with the highest degree of virulence. Thus, G. mellonella is a useful model to assess virulence in these emerging pathogens.

The Chilean plants Discaria chacaye, Talguenea quinquenervia (Rhamnaceae), Peumus boldus (Monimiaceae), and Cryptocarya alba (Lauraceae) were evaluated against Codling moth: Cydia pomonella L. (Lepidoptera: Tortricidae) and fruit fly Drosophila melanogaster (Diptera: Drosophilidae), which is one of the most widespread and destructive primary pests of Prunus (plums, cherries, peaches, nectarines, apricots, almonds), pear, walnuts, and chestnuts, among other. Four benzylisoquinoline alkaloids (coclaurine, laurolitsine, boldine, and pukateine) were isolated from the above mentioned plant species and evaluated regarding their insecticidal activity against the codling moth and fruit fly. The results showed that these alkaloids possess acute and chronic insecticidal effects. The most relevant effect was observed at 10 &micro, g/mL against D. melanogaster and at 50 &micro, g/mL against C. pomonella, being the alteration of the feeding, deformations, failure in the displacement of the larvae in the feeding medium of D. melanogaster, and mortality visible effects. In addition, the docking results show that these type of alkaloids present a good interaction with octopamine and ecdysone receptor showing a possible action mechanism.

Aphids cause significant losses in many agricultural crops and in many cases cause repeated insecticide sprays, which increase the risk of resistance. Therefore, other alternatives are needed to control them. The toxic, anti-reproductive, and feeding deterrent effects of a mannose-binding lectin isolated from bulbs of Phycella australis Ravenna (Amaryllidaceae), named Phycella australis-agglutinin (PAA) was assayed on nymphs of the aphids Acyrthosiphon pisum Harris and Myzus persicae Sulzer fed with an artificial diet. After 72 h of PAA exposure, lethal concentration (LC50) values were 109 and 313 mu g mL(-1) for A. pisum and M. persicae, respectively, while LC90 values were 248 and 634 mu g mL(-1). Sub-lethal concentrations of PAA significantly reduced the aphid fecundity at a concentration of 80 mu g mL(-1). Only a total of 5.7 descendants per female were recorded for A. pisum (32% control progeny) and 12.4 for M. persicae (39% control progeny). Acyrthosiphon pisum was strongly deterred by PAA under choice conditions, as after 72 h exposed to 80 mu g PAA mL(-1) of diet, the feeding deterrent index was 0.91 for A. pisum and only 0.38 for M. persicae. In conclusion, the mannosebinding lectin isolated from bulbs of P. australis showed acute and chronical insecticidal activity against the pea and green peach aphids.

Summary The effects on generalist predators of the insecticide lambda-cyhalothrin and a new biopesticide based on Beauveria bassiana spores were studied in the 2003 growing season (October to December, Southern spring) in Valdivia, Chile. Both pesticides target larvae of Dalaca spp. (Lepidoptera: Hepialidae), a complex formed by Dalaca chiliensis, Dalaca pallens and Dalaca variabilis. Lambda-cyhalothrin, B. bassiana spores and water (control) were sprayed once. Pitfall traps were used to sample predators one day before spraying as well as 1, 30 and 60 days after spraying. Sampling revealed an assemblage of 11 carabid species and two spider families (Lycosidae and Gnaphosidae). In order of abundance, the carabid species found were Ferionomorpha nebroides (45%), Allendia chilensis (20%), Argutoridius chilensis (13%), Ferionomorpha aerea (11%) and Ceroglossus chilensis (6%). Metius flavipes, Mimodromites cyaneus, Parhypates sp., Trechisibus angularis, Calosoma vagans and Trirammatus unistriatus accounted for less than 1% each. Spider families were almost equally represented. Activity of predators increased over time and negative effects of lambda-cyhalothrin were detected for F. nebroides, F. aerea, Lycosidae and Gnaphosidae. Differences vanished by day 60, except for F. aerea. Inundative release of B. bassiana spores affected only F. aerea at the last sampling date. Therefore, B. bassiana isolate B-931 is a good potential alternative to the broad-spectrum insecticide lambda-cyhalothrin, which disrupted the generalist predator assemblage more severely.

Conventional and biological control of a native moth, Dalaca pallens (Blanchard) (Lepidoptera: Hepialidae), were evaluated in Southern Chile in relation to changes on community metrics (diversity, species richness, evenness and dominance) of a soil-dwelling invertebrate assemblage. Two experiments were conducted (in winter and spring) to compare non-target effects of Beauveria bassiana (Balsamo) Vuillemin and lambda-cyhalothrin insecticide. The invertebrate community was sampled before and after spraying by extracting soil cores. Estimates of diversity (Shannon index), species richness, evenness (Hurlbert’s Probability of Interspecific Encounter) and dominance indicated that the invertebrate assemblage was strongly disturbed by lambda-cyhalothrin treatment but not by B. bassiana applied in winter, over the sampling period (40 days). Spring results revealed that diversity and evenness at control and at B. bassiana plots were similar between them and higher than at lambda-cyhalothrin plots, while there were no differences between sites 30 days after treatment in species richness. Inundative biological control using B. bassiana strain QU-B931 was considered to pose lower ecological risk than lambda-cyhalothrin, currently one of the most frequently used insecticides for D. pallens control.

A B S T R A C T The non-target effects of biological control are a complex matter requiring a multi-approach analysis. A fungal biopesticide is under research to control the larval stages of the ghost moth Dalaca pallens Blanchard (Lepidoptera: Hepialidae) in southern Chile. A field experiment was conducted to compare the effects of the biological control agent Beauveria bassiana (Balsamo) Vuillemin (10 12 spores ha -1 ) and the insecticide lambdacyhalothrin (7.5 g active ingredient ha -1 ) on non-target invertebrate species belonging to different guilds. The soil invertebrates were collected by using pitfall trapping and soil coring before and after spraying the biocontrol agent or the insecticide. Caught individuals were assigned to predator, herbivore or decomposer guilds and then a relatively new multivariate technique called principal response curves (PRC) was adopted to track the potential treatment effects over time in the abundance or activity of the non-target guilds. The products targeting D. pallens caused different effects on guilds: lambda-cyhalothrin decreased the activity-density of the predator guild but not herbivore or decomposer guilds, while the biological control agent caused no reduction in the activity-density of the three examined guilds. The negative effects of the insecticide were present from 1 to 60 days after treatment.