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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.

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.

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.

Dos aislamientos chilenos de Metarhizium anisopliae (Metchsnikoff) Sorokin fueron expuestos a dosis crecientes de luz ultravioleta (UV), en condiciones de laboratorio. Conidias en suspensión acuosa fueron esparcidas en placas Petri con agar y éstas fueron puestas bajo una lámpara de luz UV-C (lambda = 254 nm). Sin el protector solar, la exposición de las conidias durante 40 s redujo su germinación de 80-95% a sólo 5-2%, para QU-M221b y QU-M363, respectivamente. Usando el protector solar Blankophor P167® al 1% p/v, la germinación de las conidias, tras 40 s de exposición, se redujo desde 68-82% a 50-33% para QU-M221b y QU-M363, respectivamente. Los resultados indican que este protector solar es un potencial adjuvante para ser usado en biopesticidas basados en M. anisopliae. Two Chilean isolates of Metarhizium anisopliae (Metschnikoff) Sorokin (QU-M363 and QU-M221b) were exposed to increasing doses of ultraviolet light (UV) under laboratory conditions. Conidia suspended in aqueous solution were spread on Petri dishes containing agar-agar and were placed under a UV lamp (lambda = 254 nm). Without sunscreen, exposure of conidia to UV-C light reduced germination after 40 s from 80-95% to 5-2%, for QU-M221b and QU-M363, respectively. Using the solar screen Blankophor P167® at 1% w/v, conidia germination decreased after 40 s from 68-82% to 50-33% for QU-M221b and QU-M363, respectively. Results indicate that the sunscreen Blankophor P167 is a potential adjuvant to be used in biopesticides based on M. anisopliae.