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Effective and less risky tools for monitoring the anthropophilic sandfly Lutzomyia (Tricholateralis) cruciata (Coquillett) (Diptera: Psychodidae) are scarce, even though this sandfly species may act as a vector of Leishmania mexicana Biagi (Kinetoplastida: Trypanosomatidae) in the Americas. We evaluated the effectiveness of 1-octen-3-ol, butyric acid, lactic acid, ammonium acetate, and cyclopentanone as attractants for the collection of L. cruciata in field conditions. Chemical lures were placed in CDC light traps installed within an urban forest. A total of 122 (87.8%) individuals of L. cruciata were captured, and 79.5% were females. Other sandfly species such as Micropygomyia cayennensis cayennensis (7.9%), Micropygomyia chiapanensis (3.6%), and Dampfomyia atulapai (0.7%) were also caught. A higher and significant proportion of L. cruciata females were attracted to all compounds evaluated as compared to the other three species. The compound 1-octen-3-ol was the most attractive compound and the only one that attracts females exclusively, followed by cyclopentanone, butyric acid, and ammonium acetate. The use of 1-octen-3-ol could be recommended as an additive to CDC light traps under field conditions. [ABSTRACT FROM AUTHOR]

The chilled adult technique is a suitable strategy for the mass - release of insects for the area - wide management of insect pests. Chilling may have undesirable effects on the released insects. The relationship between physical traits and the effects of cold-induced lethargy on the fitness of Diachasmimorpha longicaudata has not been fully explored. In the present study, we evaluated the relationship between weight, size, and water and lipid content in D. longicaudata subjected to cold-induced lethargy at 9, 6, and 3°C, and the effects of cold induction on the survival, flight ability, and fecundity of parasitoid adults. During gradual chilling from 15°C to 3°C over a 45 min period, we observed that most wasps became lethargic at 9°C. The tibias of wasps that became lethargic at 3°C were larger than those of parasitoids that became lethargic at 9 and 6°C. Body water and lipid contents were higher in lethargic females chilled at 3°C, but no differences were observed in males. Lethargic males experienced reduced flight ability compared with the control, whereas fecundity was reduced only in lethargic females that had been exposed to 3°C. The survival rate was lower in both sexes. Our results suggest that greater body size and higher water and lipid contents delay the onset of cold-induced lethargy, but do not prevent negative effects on survival, fecundity, and flight ability in D. longicaudata. This study will help the advancement of parasitoid-release field programmes that use the chilled adult technique. [ABSTRACT FROM AUTHOR]

Both earthworms and terrestrial isopods have been used to evaluate the quality of contaminated soil by NPs. However, most experiments have been conducted in the laboratory and under greenhouse conditions. Besides, little is known of Fe accumulation in earthworms from iron NPs (Fe NPs) under natural conditions. Therefore, the objective of this research was to evaluate the effect of manufactured NPs on the accumulation of Fe in macroinvertebrates from forest soil. Our results revealed that earthworms consume low amounts of Fe in a concentration of 1000 mg Fe NPs kg−1 of dry soil, with a behavior constant over time. Besides, we observed that earthworms could not detect Fe at low concentrations (1 or 10 mg Fe NPs kg−1), so they do not limit soil consumption, which translates into high amounts of Fe in their bodies. By contrast, the content of Fe in organisms is inversely proportional to increasing concentrations in the soil (R2 = -0.41, p < 0.05). Therefore, although studies are needed, in addition to considering environmental factors and the physicochemical properties of the soil, endogenous worms in the evaluated area could, under natural conditions, be useful to inform us of contamination of NP manufactured from Faith. Besides, for future research, a novel methodology should be considered to demonstrate more realistic avoidance behavior under field conditions.

Functional response and mutual interference are important attributes of natural enemies that should be analysed in species with the potential to be used as biological control agents in order to increase the predictive power of the possible benefits and/or consequences of their release in the field. Our main objective was to determine the functional response and mutual interference of Coptera haywardi (Oglobin), a pupal parasitoid of economically important fruit flies (Diptera: Tephritidae). The functional response of C. haywardi on A. ludens pupae corresponded to a type II model, with an attack rate of 0.0134 host pupa/h and a handling time of 1.843 h, which reveals a meticulous selection process of pupal hosts. The effect of mutual interference among foraging females was negatively correlated with increased parasitoid density in the experimental arena, showing a gradual decline in attack rate per individual female. The increase in the number of foraging females also had an impact on the number of oviposition scars per pupa and the number of immature parasitoids per dissected pupa, but not on the percentage of adult emergence or the sex ratio. Our results suggest that C. haywardi could act as a complementary parasitoid in the control of fruit fly pupae, since the random distribution of these pupae in the soil would decrease the possibility of aggregation and mutual interference between foraging females. [ABSTRACT FROM AUTHOR]

Coffee berry borer (CBB), Hypothenemus hampei (Ferrari) (Coleoptera: Scolytinae), is a major pest of coffee worldwide. CBB females use berry volatiles while searching for hosts. Coffee volatiles can be used for monitoring CBB populations. The main objective of this study was to test under laboratory and field conditions bioactive compounds for H. hampei. In the laboratory, CBB females were attracted to the methanol‐ethanol blend (MEB), but not to methylcyclohexane, ethylbenzene, nonane, methyl salicylate, verbenone, α‐pinene, farnesene, and frontalin compared to clean air. In contrast, CBB females preferred clean air over linalool. Females were attracted to most of the tested compounds combined with the MEB over clean air, except farnesene, α‐pinene, and linalool. Females preferred clean air to α‐pinene or linalool, and they showed no preference for clean air or farnesene. Females also preferred the MEB over linalool, verbenone, α‐pinene, or farnesene when combined with MEB. The combination of tested compounds and the MEB did not increase the capture of CBB in the field. Interestingly, α‐pinene and linalool alone, or combined, inhibited the capture of CBB females and non‐target insects by trapping bait with the MEB. Thus, α‐pinene or linalool can be used in a push‐pull strategy considering the low impact over non‐target insects. [ABSTRACT FROM AUTHOR]

Male mating success depends on various traits and factors, and correctly identifying these traits can be key in the context of pest management. For tephritid pests, controlled through the sterile insect technique (SIT) traits, such as male size, can be manipulated through mass-rearing procedures. Thus, it is particularly important to understand whether male size can favor mating success. Here, we evaluated mating success of males of different sizes in Anastrepha ludens and Anastrepha obliqua, two species controlled through SIT. For both species, a morphometric analysis was performed of mated and unmated mass-reared and wild males in field cages. In both A. ludens and A. obliqua, wild females did not discriminate their mates based on male size and mated more frequently with wild males regardless of size. For mass-reared males, we found no evidence of an advantage of the large males compared to small males in mating success. However, we did find differences between the morphometric traits of mass-reared and wild males. In A. ludens, traits associated to mating success were Face Width (FW), Head Width (HW), Thorax Length (TL) and Wing Length (WL), and for A. obliqua were FW, HW, WL and WW (Wing Width). Overall, FW and TL were more consistent predictors of mating success. In conclusion, female choice seems to suggest multivariate selection, confirming that overall body size (expressed as pupal diameter, which is highly correlated with weight) is not a decisive factor in male mating success in these two species. However, morphological traits such as FW, HW, TL, WL and WW may be relevant in mating preference of wild female. [ABSTRACT FROM AUTHOR]

The capacity of a parasitoid to discriminate hosts can favor the survival of its progeny as well as improve its efficacy as a biocontrol agent when it is used with another natural enemy, as this may result in greater control of the pest. Our aim was to characterize the discrimination ability of Coptera haywardi (Oglobin) (Hymenoptera: Diapriidae) females with respect to puparia of Anastrepha obliqua (Macquart) (Diptera: Tephritidae) treated with the fungus Beauveria bassiana (Balsamo) Vuillemin (Hypocreales: Cordycipitaceae), under three conditions: (1) no choice, separately exposing A. obliqua puparia, treated at 0, 24, 48, or 72 h prior to exposure, to the parasitoid and without application of the fungus (absolute control); (2) with the possibility of choosing between untreated and treated puparia with the same times after fungus application; and (3) multiple choice, where parasitoids could select among puparia treated at different times. Observations were made to determine the discrimination behavior of the wasps as well as the number of ovipositions by each female parasitoid; 14 observations were made. Coptera haywardi exhibited different levels of discrimination depending on the test. In the no‐choice test, discrimination was not observed; in the two‐choice test, females significantly discriminated the puparia treated at 0, 24, and 72 h prior to exposure; and in the multiple‐choice test, females preferred the untreated puparia – behavior that was corroborated in the direct observations. Oviposition time ranged from 9 to 86 min and differences in average time among treatments were not significant. We conclude that the discrimination ability of C. haywardi allows the simultaneous use of B. bassiana, as females prefer healthy, untreated puparia without interfering with the fungus. [ABSTRACT FROM AUTHOR]