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Mexico is a center of New World crop origins with many insect species associated with the wild crop relatives, some of which have become pests of cultivated plants. Many of these indigenous pests of Mexico are weevils (Coleoptera: Curculionidae), and some represent potential quarantine pests. In the present work, we present some of the most important species of weevils considered as crop pests, which are presently restricted primarily to Mexico with the potential to invade other regions. We also present species of weevils exotic to Mexico, considered by national quarantine authorities to be possible threats to Mexican agriculture. Potential quarantine weevil pests for avocado include Conotrachelus aguacatae Barber, Conotrachelus perseae Barber, Heilipus lauri Boheman, Heilipus albopictus Champion, and Copturus aguacatae Kissinger (all Coleoptera: Curculionidae). For guava, species include Conotrachelus dimidiatus Champion and Conotrachelus copalensis Salas-Araiza and Romero-Nápoles (both Coleoptera: Curculionidae). Weevil pests reported with quarantine importance for sugar cane are Sphenophorus incurrens Gyllenhal (Coleoptera: Dryophthoridae), Apinocis angustus (Casey), and Apinocis subnudus (Buchanan) (both Coleoptera: Curculionidae). The weevil Rhyssomatus nigerrimus Fåhraeus (Coleoptera: Dryophthoridae) recently has been observed damaging soybeans in northern and southern Mexico. Cactophagus spinolae Gyllenhal (Coleoptera: Dryophthoridae) is a generalist cactus pest. Scyphophorus acupunctatus Gyllenhal (Coleoptera: Dryophthoridae) is a well-known pest of cultivated and wild agaves. Several species of Epicaerus (Coleoptera: Curculionidae) have been reported on various crops in restricted areas including, among others, Epicaerus operculatus (Say) on garlic, and Epicaerus cognatus Sharp (both Coleoptera: Curculionidae) on potato. Amphidees latifrons (Sharp) (Coleoptera: Curculionidae) has been reported from apples in localized regions of northern Coahuila. Weevils exotic to Mexico of quarantine concern are Naupactus cervinus Boheman, Diaprepes abbreviatus (L.) (both Coleoptera: Curculionidae), and Rhynchophorus ferrugineus (Olivier) (Coleoptera: Dryophthoridae).

Abstract Heilipus lauri is a specialist avocado seed feeding weevil native to parts of México and is an invasive pest in Colombia. This weevil is considered an incursion risk because possible unintended introductions into areas outside of its native range can result in establishment, which threatens avocado production in invaded regions. Despite being a well-recognized pest of avocados, relatively little is known about oviposition biology, behavior, and cultivar preferences of this weevil. Field studies in commercial Hass avocado orchards in México and laboratory studies in a quarantine facility in California (USA) indicated that H. lauri prefers to oviposit into middle and bottom thirds of fruit. In the laboratory, an average of 1.7 eggs (range 1–6 eggs) are laid over a 24-h period in oviposition chambers by individual females. Conspecifics add eggs to these clutches, with up to 17 eggs being recorded in 1 oviposition chamber. This finding suggests that H. lauri does not use an oviposition deterring pheromone. Female weevils readily oviposit in artificial holes representing mechanical wounds on fruit. In comparison to the commercially dominant Hass variety, fruit from Lamb Hass and G22, a native Guatemalan variety, and to a lesser extent Gem, may be less preferred for oviposition when females have a choice of fruit in which to oviposit. Videography studies indicated that H. lauri exhibits predominantly diurnal activity with respect to oviposition behaviors, feeding, and walking. Graphical Abstract Graphical Abstract

Heilipus lauri Boheman (Coleoptera: Curculionidae) is a specialist pest of avocado fruit and is considered an incursion risk for U.S. avocado producers. At the time work reported here was undertaken the flight capabilities of H. lauri were unknown. Consequently, proactive studies were undertaken to quantify aspects of this pest’s flight capabilities to inform potential future control efforts. Flight mill studies were conducted in a quarantine laboratory to measure the dispersal capacity of H. lauri with respect to gender, mating status, and size on the single and repeat flight capabilities of weevils. Gender, mating status, and size did not significantly affect measured flight parameters. Average total distances flown and flight velocity, and mean maximum flight bout distances and durations significantly declined as weevil age increased and when weevils engaged in repeat flights. Survivorship rates were significantly reduced as the number of successive flights undertaken increased. The distribution of total average flight distances flown and total cumulative flight distances flown was platykurtic. The implications of these findings are discussed in terms of developing incursion management plans. Graphical Abstract

Biodiesel is a mixture of monoalkyl esters of fatty acids derived from vegetable oils or animal fats. Agricultural residues are a potential source of raw materials for generating biofuels. The aim of this research was to determine the usefulness of Persea schiedeana Nees fruit as a potential source to be transformed into biodiesel by alkaline transesterification. In this sense, biodiesel was obtained using oil isolated from overripe fruits of P. schiedeana, damaged by the Heilipus lauri pest. The fruits were collected in the municipality of Huatusco, Veracruz, Mexico. The maceration of the fruits with hexane resulted in an oil with a high percentage of free fatty acids (8.36 ± 1.35%). The main components of the biodiesel were methyl oleate (53.12%) and methyl palmitate (25.74%). The dynamic viscosity of the biodiesel complies with ASTM D6751 and EN 14214 and the biodiesel blends with commercial diesel comply with ASTM D675, the calorific value showed an increase with increasing biodiesel concentration in the blends. This study demonstrates that the oil obtained from the overripe and surplus fruits of P. schiedeana is a viable feedstock for the production of a fuel to replace diesel.

Mexican avocado producers face phytosanitary barriers that limit the ability to ship avocados to foreign markets due to concerns about invasion by unwanted pests. The principal regulated pests are the big avocado seed weevil, Heilipus lauri Boheman; the small avocado seed weevils Conotrachelus aguacatae Barber and C. perseae Barber; the branch borer weevil, Copturus aguacatae Kissinger (all Coleoptera: Curculionidae); and the avocado seed moth, Stenoma catenifer Walsingham (Lepidoptera: Elachistidae). In Mexico, distribution information of these pests is largely based on a slow integration of the geographic data. This study was conducted to determine the potential distribution of these 5 insect pests in Mexican avocadogrowing areas by using the maximum entropy algorithm. Distributional data of these insects were obtained from scientific literature, databases, and field collection, and incorporated into the MaxEnt model using 19 global climatic variables and elevation data. Distributional models for Mexico, and geographic interaction with avocado-growing areas of the country, were calculated. Conoctrachelus aguacatae, C. perseae, Copturus aguacatae, and H. lauri showed similar environmental suitability patterns in Mexico, with a potential distribution from central to southern Mexico. High suitability was projected principally in the Trans-Mexican Volcanic Belt and surrounding biogeographic provinces. Stenoma catenifer exhibited an irregular environmental suitability pattern, with preference for western Mexico. Altitude, isothermality, and seasonality of precipitation were the variables that most influenced potential distribution of analyzed species. Geographic interaction with avocado-growing areas ranged from wider (Conoctrachelus aguacatae, C. perseae, Copturus aguacatae, and S. catenifer) to narrow or irregular (H. lauri), but the last species has the potential to invade new geographic areas. For the first time, the geographic distribution of these 5 insect pests was determined based on environmental suitability and their geographic interaction with avocados. These data could support development of management strategies throughout the country, and help focusing surveys and control tactics.

Determinar la distribución espacial de poblaciones de Heilipus lauri y Stenoma catenifer, insectos de importancia económica y cuarentenaria en aguacate, constituye una información útil y de aplicación en el diseño e implementación de programas de monitoreo y manejo integrado de plagas. La distribución espacial agregada es considerada uno de los patrones más comunes en la naturaleza, no obstante, no ha sido documentada para estas especies de insectos plaga. Se propone a través de métodos de estadística espacial el análisis de datos provenientes de monitoreos periódicos donde se registró el número de frutos con daño ocasionado por los dos insectos plaga. El estudio se realizó entre el 2019-2020 en cuatro huertos comerciales de aguacate cv. Hass en el departamento de Cauca, Colombia. Se estableció un diseño de muestreo basado en el reconocimiento del daño sobre árboles previamente geoposicionados. La distribución espacial se determinó a través de la Ley de poder de Taylor y la función K de Ripley. El coeficiente de agregación de Taylor (b) fue de 1,47 y 1,22 para H. lauri y S. catenifer, respectivamente, lo cual indicó agregación. La función K de Ripley, identificó puntos de agregación de frutos con daño (FCD) en un rango de 5-35 metros de radio, siendo los puntos de agregación consistentes en los dos ciclos productivos. Los registros de los frutos afectados se mapearon, identificando los sitios de mayor agregación sobre los cuales se definen e implementan las estrategias de manejo de las plagas cuarentenarias en sitios específicos del cultivo que señalan la ubicación espacial donde se concentra el daño y poblaciones de H. lauri y S. catenifer. 

El aguacate 'Hass' es un producto con potencial de exportación pero los daños presentados por insectos perforadores lo restringen para el norte del Tolima (Colombia). Para plantear su manejo se estableció la cría de la especie involucrada con frutos afectados individualmente. Se determinó el número de días en estado pupal para observar su morfología y determinar la magnitud de daño en el fruto y en la cosecha. Las cámaras de cría tipo tarrina o cajas tipo mantequillero fueron las más convenientes para la cría (P≤0,05) con suelo estéril o toalla absorbente y la desinfección del fruto con hipoclorito de sodio al 2%. La observación y confrontación de las características morfológicas externas de los especímenes con claves taxonómicas se encontró como Heilipus lauri Boheman (Coleoptera: Curculionidae). El insecto empupó a los 65,3±1,42 días, el estado pupal 15,14±0,33 días y la emergencia del 80,1±1,36 días. El daño en el fruto ocasionó una perforación en la epidermis con presencia de una costra circular negra, presencia de excretas blanquecinas y barrenación de la larva en pulpa y semilla. La evaluación en 12 árboles en producción para ocho fincas diferentes de Fresno y Herveo, registró el 0,03% y el 3,21% de daño (peso), respectivamente. El análisis de regresión múltiple (Stepwise) mostró que la cantidad de plateos/ año se correlaciona con el porcentaje de árboles infestados (P≤0,05 y r2 = 0,73).