Essential oils can be used as an alternative to using synthetic insecticides for pest management. Therefore, the insectistatic and insecticidal activities of the essential oil of aerial parts of Salvia ballotiflora (Lamiaceae) were tested against the fall armyworm Spodoptera frugiperda (Lepidoptera: Noctuidae). The results demonstrated insecticidal and insectistatical activities against this insect pest with concentrations at 80 µg·mL⁻¹ resulting in 20% larval viability and 10% pupal viability. The larval viability fifty (LV₅₀) corresponded to a concentration of 128.8 µg·mL⁻¹. This oil also increased the duration of the larval phase by 5.5 days and reduced the pupal weight by 29.2% withrespect to the control. The GC-MS analysis of the essential oil of S. ballotiflora showed its main components to be caryophyllene oxide (15.97%), and β-caryophyllene (12.74%), which showed insecticidal and insectistatical activities against S. frugiperda. The insecticidal activity of β-caryophyllene began at 80 µg·mL⁻¹, giving a larval viability of 25% and viability pupal of 20%. The insectistatic activity also started at 80 µg·mL⁻¹ reducing the pupal weight by 22.1% with respect to control. Caryophyllene oxide showed insecticidal activity at 80 µg·mL⁻¹ giving a larval viability of 35% and viability pupal of 20%.The insectistatic activity started at 400 µg·mL⁻¹ and increased the larval phase by 8.8% days with respect to control. The LV₅₀ values for these compounds were 153.1 and 146.5 µg·mL⁻¹, respectively.

Spodoptera frugiperda J. E. Smith (Lepidoptera: Noctuidae) (fall armyworm) is a pest native to the Americas that affects a variety of crops. Its control is based on chemical insecticides. However, this practice has been associated with changes in the susceptibility of pests to various insecticides. The use of plant products represents an eco-friendly alternative. The objective of this work was to evaluate the larvicidal activity of the chloroform extract of Senna crotalarioides (Kunth) H.S. Irwin & Barneby (Fabaceae) to control S. frugiperda. The chloroform extract of S. crotalarioides caused significant larval mortality, and reduced pupal weight and adult emergence. The analysis by gas chromatography coupled with mass spectrometry (GC-MS) revealed the presence of 22 compounds in the chloroform extract of S. crotalarioides leaves, with the straight-chain aliphatic fatty alcohol 1-octacosanol as the main component. This study revealed that the leaves of S. crotalarioides synthesize long chain alcohols, which increased the mortality of S. frugiperda in its larval stage, including the pupal stage. The extract also caused a decrease in the S. frugiperda pupal weight. The potential use of the chloroform extract obtained from S. crotalarioides and its principal chemical constituent is proposed as a promising alternative to control S. frugiperda.

The use of botanical extracts of the plant Jatropha curcas (Euphorbiaceae) represents a valuable alternative to control insect pests and avoid the detrimental effects on the environment and health that arise due to synthetic chemical insecticides. Thus, we conducted a systematic review to summarize the published evidence on the bioactivity of J. curcas against insect pests. Electronic databases were searched to identify studies that assessed J. curcas extracts against insect pests in various types of crops. We included 39 articles that reported the insecticidal and insectistatic activity of several botanical extracts from J. curcas against insects of eight different taxonomic orders. The evidence demonstrates that aqueous and methanolic extracts from seeds and leaves, seed oil, and petroleum ether seed extracts were effective against insect pests of stored grains, aphids of cabbage and sorghum, fruit flies, and desert locusts. The extracts caused high mortality, controlled the populations, reduced oviposition, diminished hatchability, and increased the antifeedant effect. However, the type of solvent used to obtain the botanical extract and the method of application (contact or food) are fundamental to increase its bioactivity. Therefore, botanical extracts from seeds and leaves of J. curcas should be considered as an alternative against insect pests and may be incorporated into integrative and sustainable management for insect control.

The repeated application of synthetic insecticides has the potential to induce insecticide resistance. Plant extracts are a good source of bioinsecticides, as these extracts often have several bioactive compounds, thus reducing the occurrence of resistance. The genus Trichilia (Meliaceae) is distributed widely in Mexico and it is a sustainable source of bioactive compounds because their bark is shed annually and may be collected without harming the tree. This research evaluated the effect on mortality, weight, larval and pupal duration, fecundity, and fertility of Copitarsia decolora Guenée (Lepidoptera: Noctuidae) when fed with a diet supplemented with different concentrations of hexane, ethyl acetate, acetone, methanol, and aqueous extracts of the Trichilia americana Sessé & Moc., Trichilia hirta L., and Trichilia havanensis Jacq. (Meliaceae) bark. All the extracts provoked a dose-response effect on the variables evaluated. The hexane extract of the 3 species was lethal to the larval stage, wit... Resumen La aplicación repetida de insecticidas sintéticos tiene el potencial de inducir resistencia a los insecticidad. Los extractos de plantas son una buena fuente de bioinsecticidas, ya que estos extractos a menudo tienen varios compuestos bioactivos, lo que reduce la apariencia de resistencia. El género Trichilia (Meliaceae) está ampliamente distribuido en México y es una fuente sustentable de compuestos bioactivos ya que su corteza se desprende anualmente y puede recolectarse sin dañar el árbol. Este trabajo evaluó el efecto sobre la mortalidad, peso, duración de larvas y pupas, fecundidad y fertilidad de Copitarsia decolora Guenée (Lepidoptera: Noctuidae) al ser alimentadas con una dieta suplementada a diferentes concentraciones de extracto hexánico, acetato de etilo, acetónico, metanólico y acuoso de corteza de Trichilia americana Sessé & Moc., Trichilia hirta L., y Trichilia havanensis Jacq. (Meliaceae). Todos los extractos provocaron un efecto de dosis respuesta sobre las variables evaluadas. El ...

Longhorn beetles (Coleoptera: Cerambycidae) feed during their larval stage on wood from recently dead or diseased trees and may have a wide variety of hosts. However, reports of larval hosts for Cerambycidae could be misinterpreted from field observations. The use of freshly cut branches to attract longhorn beetles is a method that provides reliable information about which hosts they use. This study reports new records of larval hosts of longhorn beetles in the tropical dry forest of San Andres de la Cal, Morelos, Mexico. In the study area, species of woody plants were sampled, from each of which sections of branches were cut and left exposed to local field conditions for two months to attract beetles. Branches were later collected and placed in emergence chambers. A total of 26 species of Cerambycidae emerged from the branches of 51 species of woody plants of the families Apocynaceae, Araliaceae, Burseraceae, Celastraceae, Convolvulaceae, Euphorbiaceae, Fabaceae, Juglandaceae, Malpighiaceae, Ma... Resumen. Los escarabajos longicornios (Coleoptera: Cerambycidae) en su etapa larvaria se alimentan de madera de árboles recién muertos o enfermos, y pueden llegar a tener una amplia variedad de hospederos. Sin embargo, los reportes de hospederos larvales de Cerambycidae podrían ser malinterpretados a partir de observaciones de campo. El uso de ramas recién cortadas para la atracción de escarabajos longicornios es un método que permite obtener información confiable de los hospederos que emplean. Este estudio reporta nuevos registros de hospederos larvales de escarabajos longicornios en el Bosque Tropical Caducifolio del ejido de San Andrés de la Cal, Tepoztlán, Morelos, México. En la zona de estudio, se muestrearon diferentes especies de plantas leñosas, a cada una de éstas se les cortaron secciones de las ramas de los árboles y se dejaron expuestas al ambiente durante dos meses para la atracción de escarabajos. Posteriormente las secciones fueron recolectados y se colocaron en cámaras de emergencia. Un to...

Lignocellulosic biomass is a source of carbohydrates that can be used in the production of biogas. The aim of this study was to obtain biogas from biomass waste (leaves, stems and seed bagasse) of Ricinus communis, applying pretreatments such as temperature and humidity. We examined the effect of these pretreatments on the biomass, two enzymatic pretreatments (cellulase and cellobiohydrolase), two chemicals (NaOH and HCl) and two controls (dried castor straw and seed bagasse) on the methane content. The experiment was performed in two anaerobic digestion (AD) assays at a controlled temperature (37 °C) and at room temperature, with a hydraulic retention time (HRT) of 55 days. The results showed that the residues of the seed bagasse produced the highest biogas yields both at room temperature and at the controlled temperature since this material at 37 °C produced 460.63 mL gVS⁻¹ under cellulase pretreatment; at room temperature, the highest level of production was found for the control (263.41 mL gVS⁻¹). The lowest yields at the controlled temperature and room temperature were obtained from residues of Ricinus communis treated with cellobiohydrolase and the seed bagasse treated with alkaline (15.15 mL gVS⁻¹ and 78.51 mL gVS⁻¹, respectively). Meanwhile, the greatest amount of methane was produced by seed bagasse treated with cellobiohydrolase at a controlled temperature (92.2% CH₄) and the lowest content of CH₄ (15.5%) was obtained at a controlled temperature from castor straw under the control treatment.