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The defoliator Physocleora dukinfeldia Schaus 1897 (Lepidoptera: Geometridae) was recently reported attacking Eucalyptus urograndis (Myrtaceae) plantations in Brazil, raising concerns about its potential impact on commercial forestry. In this context, early characterization of pest biology plays a critical role in understanding host-use patterns and forecasting potential impacts on forest ecosystems. This study aimed to characterize the biology and foliar consumption of P. dukinfeldia on E. urograndis and its native host, Schinus terebinthifolia (Anacardiaceae), by recording molting, mortality, pupation, and emergence of imago, measuring larval head capsule width, pupal weight, and size, and calculating stage duration and viability under controlled conditions. The insect completed its life cycle on both host plants, with significantly longer development time and reduced pupal viability observed on E. urograndis . Although larval survival was low on both host species, nearly one-third of the individuals successfully reached adulthood. No significant differences in leaf consumption were detected between the two eucalyptus species evaluated in this study. These findings indicate that P. dukinfeldia has the biological capacity to adapt to eucalyptus and should be closely monitored in forest production areas. This is the first report to detail the life cycle and feeding behavior of this species on eucalyptus, providing critical baseline information for future pest management strategies.

Extracts and essential oils from plants are important natural sources of pesticides. These compounds are considered an alternative to control ectoparasites of veterinary importance. Schinus molle, an endemic species of Brazil, produces a high level of essential oil and several other compounds. The aim of this work was to determinate the chemical composition of extracts and essential oils of S. molle and further to evaluate the activity against eggs and adults of Ctenocephalides felis felis, a predominant flea that infests dogs and cats in Brazil. In an in vitro assay, the non-polar (n-hexane) extract showed 100% efficacy (800 µg cm−2; LD50 = 524·80 µg cm−2) at 24 and 48 h. Its major compound was lupenone (50·25%). Essential oils from fruits and leaves were evaluated, and had 100% efficacy against adult fleas at 800 µg cm−2 (LD50 = 353·95 µg cm−2) and at 50 µg cm−2 (LD50 = 12·02 µg cm−2), respectively. On the other hand, the essential oil from fruits and leaves was not active against flea eggs. This is the first study that reports the insecticidal effects of essential oils and extracts obtained from Schinus molle against Ctenocephalides felis felis.

The expression of plant secondary metabolism is strongly controlled by plant both in time and space. Although the variation of secondary metabolites, such as soluble and structural phenolics (e.g., lignins), has been largely observed in gall-inducing insects, and compared to their non-galled host organs, only a few datasets recording such variation are available. Accordingly, the relative importance of spatiotemporal variability in phenolic contents, and the influence of gall developmental stages on the original composition of host organs are poorly discussed. To address this knowledge gap, we histochemically determined the sites of polyphenol and lignin accumulation, and the polyphenol contents in three developmental stages of two calophyid galls and their correspondent host organs. Current results indicate that the compartmentalization of phenolics and lignins on Schinus polygama (Cav.) Cabrera follows a similar pattern in the two-calophyid galls, accumulating in the outer (the external tissue layers) and in the inner tissue compartments (the cell layers in contact with the gall chamber). The non-accumulation in the median compartment (median parenchyma layers of gall wall with vascular bundles, where gall inducer feeds) is important for the inducer, because its mouth apparatus enter in contact with the cells of this compartment. Also, the concentration of phenolics has opposite dynamics, decreasing in leaf galls and increasing in stem galls, in temporal scale, i.e., from maturation toward senescence. The concentration of phenolics in non-galled host organs, and in both galls indicated the extended phenotype of Calophya rubra (Blanchard) and C. mammifex Burckhardt & Basset (Hemiptera: Sternorrhyncha: Psylloidea: Calophyidae) over the same host plant metabolic potentiality.

The human head louse, Pediculus humanus capitis (Anoplura: Pediculidae), is an ectoparasite confined to the scalp and human hairs. The repeated use of insecticides for the control of head lice during past decades has resulted in the development of marked levels of resistance. Natural compounds such as essential oils (EOs) have been suggested as alternative sources for insect control agents. In order to introduce a new pediculicide based on EOs, the effectiveness of the product and their effects on human being must be analyzed. In consequence, the biological activity of EOs from the leaves and fruits of Schinus areira (Anacardiaceae) and the leaves of Thymus vulgaris (Lamiaceae), Aloysia polystachya and Aloysia citriodora (Verbenacea) were evaluated against the eggs and adults of P. humanus capitis by fumigant and contact toxicity bioassays. Additionally, dermal corrosion/irritation tests were performed on New Zealand albino rabbits. In a fumigant bioassay, EOs from the leaves and fruits of S. areira were the most toxic against P. humanus capitis adults while these EOs and T. vulgaris were the most effective against the eggs. In contact bioassay, the EO from T. vulgaris was the most toxic against both stages. In the corrosion/irritation tests, the EOs did not produce dermal effects. According to the results, the essential oils from the leaves of T. vulgaris would be a valid tool for the management of P. humanus capitis. This EO produces a high knockdown effect in adults (followed by mortality) and toxicity in the eggs when it is applied for 21 min at a low concentration.

BACKGROUND: The ability of mosquitoes of the genus Aedes and its allies, such as Stegomyia, to transmit diseases such as dengue and yellow fever, makes them important in public health. This study aims to evaluate the use of the essential oil of Brazilian pepper in biological control of by assessing and quantifying the larvicidal effect against S. aegypti, the only available access to dengue control, and test its risk of genotoxicity with Salmonella typhimurium as an indicator of safety for its environmental use. RESULTS: The density of the oil was 0.8622 g mL-1. Gas chromatography coupled with mass spectrometry revealed six major constituents: δ-3-carene (55.43%), α-pinene (16.25%), sylvestrene (10.67%), germacrene D (2.17), β-myrcene (1.99%), and isoterpinolene (1.4%). The minimum inhibitory dose to larvae development was 862.20 μg mL-1. The median lethal dose (LD50) of the essential oil for larvae was between the concentrations of 172.44-344.88 μg mL-1. There was no mutagenic risk for the essential oil, since there were no biochemical or morphological changes in S. typhimurium after exposure to the essential oil. CONCLUSIONS: The minimum inhibitory essential oil concentration and the median lethal dose pointed to the value of the use of water dispersions of Brazilian pepper essential oil as an environmental safe natural larvicidal for S. aegypti.

BACKGROUND: Alternative insecticides for the control of malaria and filarial vectors are of paramount need as resistance is increasing among classes of insecticides currently in use in the public health sector. In this study, mosquitocidal activity of Schinus terebinthifolia essential oil against Anopheles gambiae s.s., An. arabiensis and Culex quinquefasciatus was assessed in laboratory, semi- field and full- field conditions METHOD: Twenty third instar larvae of both Anopheles gambiae s.s. and Cx. quinquefasciatus were exposed to different dosages of plant extract in both laboratory and semi- field environments. Observation of the mortality response was assessed at intervals of 12, 24, 48 and 72 hours. Adult semi- gravid female mosquitoes were exposed to papers treated with S. terebinthifolia and compared with WHO standard paper treated with alphacypermethrin (0.05%). RESULTS: Gas chromatography, coupled to mass spectrometry, identified 15 compounds from S. terebinthifolia extracts, the most abundant identified compound was δ-3-carene (55.36%) and the least was γ-elemene (0.41%). The density of the oil was found to be 0.8086 g/ml. The effective dosages in the insectary ranged from 202.15 to 2625.20 ppm and were further evaluated in the semi- field situation. In the laboratory, the mortality of Cx. quinquefasciatus ranged from 0.5 to 96.75% while for An. gambiae s.s it was from 13.75 to 97.91%. In the semi- field experiments, the mortality rates observed varied for both species with time and concentrations. The LC₅₀ and LC₉₅ value in the laboratory was similar for both species while in the semi- field they were different for each. In wild, adult mosquitoes, the KT₅₀ for S. terebinthifolia was 11.29 minutes while for alphacypermethrin was 19.34 minutes. The 24 hour mortality was found to be 100.0% for S. terebinthifolia and 75.0% for alphacypermethrin which was statistically significant (P < 0.001). CONCLUSION: The efficacy shown by essential oils of fruits and seeds of S. terebinthifolia has given an opportunity for further investigation of individual components of these plant extracts and to evaluate them in small- scale field trials.

Background The aim of this study was to isolate and identify the antifungal compounds from the extracts of Schinus terebinthifolius (Anacardiaceae) against clinical isolates of the pathogenic fungus Paracoccidioides brasiliensis . Methods The hexane and dichlomethane fractions from leaves and stems of S. terebinthifolius were fractionated using several chromatography techniques to afford four compounds. Results The compounds isolated from S. terebinthifolius were identified as schinol ( 1 ), a new biphenyl compound, namely, 4'-ethyl-4-methyl-2,2',6,6'-tetrahydroxy[1,1'-biphenyl]-4,4'-dicarboxylate ( 2 ), quercetin ( 3 ), and kaempferol ( 4 ). Compounds 1 and 2 were active against different strains of P. brasiliensis , showing a minimal inhibitory concentration value against the isolate Pb B339 of 15.6 μg/ml. The isolate Pb 1578 was more sensitive to compound 1 with a MIC value of 7.5 μg/ml. Schinol presented synergistic effect only when combined with itraconazole. The compounds isolated from S. terebinthifolius were not able to inhibit cell wall synthesis or assembly using the sorbitol assay. Conclusion This work reveals for the first time the occurrence of compound 2 and discloses activity of compounds 1 and 2 against several clinical isolates of P. brasiliensi s. These results justify further studies to clarify the mechanisms of action of these compounds.

BACKGROUND: Dengue has become the subject of public health programs worldwide. The lack of a vaccine and the high environmental risk of synthetic insecticides, arouse the interest in natural products against this vector. This study aimed to determine the chemical composition of the essential oil of ripe fruits and seeds of Schinus terebinthifolia Raddi; to evaluate the essential oil effect on mortality of Stegomyia aegypti (Linnaeus, 1792) larvae; and to characterize the structural damage suffered by larvae and their association with different contents of essential oil. METHODS: Ripe fruits and seeds were crunched and their essential oil was extracted through hydrodistillation, purified, and its phytochemical analysis was carried out through High Resolution Gas Chromatography, coupled with Mass Spectrometry. This essential oil was diluted in a 10-point gradient of 86.22 – 862.20 ppm, at regular intervals of 86.22 ppm. Each point received 50 larvae and the assessments of surviving were made at 24, 48 and 72 hours after inoculation. Structural damage was assessed through measurements of thickness with exoskeleton, evaluating the integrity of the head, thorax, abdominal segments, and air siphon, using ImageJ® software. Statistical data analysis was carried out through Logistic Regression and Discriminant Analysis. RESULTS: 56 substances were identified, corresponding to 81.67% of the essential oil composition. Larvae were dose-dependent susceptible to the essential oil; the concentration produced a significant effect on larval mortality. Among the major deformations found in the larvae, it was detected inhibition of chitin synthesis by the activity of the oil, thus reducing the deposition of cuticle layers. CONCLUSION: The essential oil caused death in exposed larvae after 72 hours, in a dose-dependent manner. It also changed the structure of exposed larvae, indicating a direct effect on larval exoskeleton. The results open up possibilities for the use of natural products as an alternative to control dipterans.

The presence of the psyllid Calophya schini infesting the Peruvian pepper tree, Schinus molle, was detected in several localities in the region of Lisbon, in Portugal. This is the first record of this jumping plant-louse in Europe and the Palaearctic region.