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The weevil Scyphophorus acupunctatus Gyllenhal (Coleoptera: Cuculionidae) is the most important insect pest of wild and cultivated agaves worldwide.This weevil causes direct damage while feeding and egg laying on host plants, and indirect damage due to the wounds on agave tissue that may serve as an entry for plant pathogens. Sampling and control of this weevil is complicated because of its cryptic habits. Thus, the use of synthetic aggregation pheromone-baited traps may be a useful tool for monitoring or control of this pest. The attraction of agave weevil to pheromone traps is synergized by the presence of host plant tissue. In this study, we evaluated the effect of the amount of fresh agave tissue and bagging of the plant tissue on the capture of S. acupunctatus with pheromone-baited traps in a blue agave crop. The highest captures of weevils were obtained in traps baited with the synthetic pheromone plus 400 g of agave tissue. Weevil capture rate was increased when the food bait was placed into a plastic bag or plastic container with holes as compared with unbagged food bait. ResumenEl picudo Scyphophorus acupunctatus Gyllenhal (Coleoptera: Curculionidae) es uno de los problemas fitosanitarios de mayor importancia economica en agaves cultivados y silvestres en Mexico. La importancia de esta plaga en agaves radica en que provoca danos directos por alimentacion y/u oviposicion, e indirectos ya que las heridas causadas por esta plaga pueden servir de entrada a microorganismos fitopatogenos del agave. Debido a que todo el ciclo biologico de esta plaga ocurre en el interior de la planta de agave, su muestreo es complicado y por ende resulta dificil monitorear su densidad poblacional en plantaciones de agave para tomar decisiones sobre su manejo; asi, el uso de trampas con feromona de agregacion sintetica es una buena opcion para su monitoreo. La respuesta de los picudos a la feromona de agregacion sintetica es sinergizada por la presencia de la planta hospedera. Por lo tanto es necesario determinar si la cantidad de tejido de agave y si el embolsado del cebo afecta la captura de los insectos. En la presente investigacion se evaluaron diferentes cantidades de tejido fresco de agave y dos formas de embolsar el alimento para la captura de S. acupunctatus en agave tequilero. Se encontro que las mayores capturas de picudos se obtuvieron en las trampas cebadas con feromona de agregacion sintetica mas 400 g de tejido de agave. El colocar el tejido de agave en bolsa o bote de plastico transparente con orificios incremento el numero de picudos capturados por trampa comparado con el cebo sin embolsar. View this article in BioOne

Sphenophorus incurrens Gyllenhal (Coleoptera: Curculionidae) is an insect that feeds mainly on plants of the family Poaceae in the Neotropics. In Mexico, this weevil is an emergent pest of sugarcane. In this study, first the behavioral responses of both sexes to conspecifics were evaluated in a Y-tube olfactometer. Second, the volatiles of S. incurrens were sampled by the dynamic headspace technique and analyzed by gas chromatography coupled with electroantennographic detection (GC-EAD). Third, the antennal-active compound was identified by gas chromatography coupled with mass spectrometry. Finally, the biological activity of the identified compound was evaluated in laboratory and field tests. Our results showed that males emitted a pheromone that attracts both sexes. The GC-EAD analysis of the male volatiles showed that one peak elicited antennal responses from male and female weevils. The compound was identified as 2-methyl-4-octanol. Laboratory and field tests showed that the identified compou...

Scyphophorus acupunctatus Gyllenhal (Coleoptera: Dryophthoridae) is one of the most important insect pests of wild and cultivated agaves in Mex ico. For managing this weevil, it is important to have a method for detecting and sampling its population density. The weevil’s life cycle takes place inside the agave plant, which makes sampling of the weevil difficult. The use of traps baited with synthetic pheromone plus agave tissue is a useful tool for sampling the population density of this pest. Using the capture-mark-release-recapture method, we investigated the attraction range of traps baited with synthetic pheromone plus agave tissue to capture S. acupunctatus. We also evaluated several inter-trap distances to determine the best density of traps for monitoring this insect. Our results showed that these traps attracted S. acupunctatus up to a range of 120 m. In addition, we found that the cardinal point at which weevils were released affected their recapture. The results also showed that, in general, experiments with the longest inter-trap distances captured the most weevils. Thus, traps placed at 100 m in the 1st experiment, 200 m in the 2nd experiment, and 250 m in the 3rd experiment captured more weevils than traps placed at shorter distances. Based on our results of attraction range and inter-trap distances, we suggest that these pheromone-baited traps could be used for monitoring S. acupunctatus at densities of 1 trap per 6 ha of blue agave crop.

Summary The effect of height and distribution pattern of traps on the capture of Scyphophorus acupunctatus Gyllenhal (Coleoptera: Dryophthoridae) on blue agave (Asparagales: Asparagaceae) in commercial plantations was studied. Results showed that the trap height and the distribution pattern did not have an effect on the number of captured weevils per trap. In contrast, the inter-trap distance had an effect on the number of captured weevils per trap. For monitoring this weevil in blue agave commercial plantations, we recommend to use the pheromone and agave tissue-baited traps placed at ground level, at 200 m distance between traps, and distributed in a square distribution pattern.

In this study, volatile compounds emitted by disturbed nymphs and adults of the stink bug Antiteuchus innocens were identified by gas chromatography-mass spectrometry as follows: (E)-hexenal, α-pinene, (E)-2-heptenal, n-decane, (E)-2-octenal, n-undecane, n-dodecane, and n-tridecane. The major components were (E)-2-hexenal, (E)-2-heptenal, and n-undecane. The same compounds, except α-pinene and (E)-2-octenal, were found in the dorsal glands and metathoracic glands of nymphs and adults, respectively. Extracts of exocrine glands did not elicit antennal responses of the adults, or affect the behavior of fifth instar nymphs, which suggests that these compounds are likely involved in the A. innocens defense rather than functioning as an alarm pheromone. Sumario En este estudio, los compuestos volatiles emitidos por las ninfas y adultos molestados de la chinche apestosa Antiteuchus innocens fueron identificados por cromatografia de gases-espectrometria de masas como (E)-hexenal, α-pineno, (E)-2-heptenal, n-decano, (E)-2-octenal, n-undecano, n-dodecano, and n-tridecano. Los compuestos mayoritarios de la mezcla fueron el (E)-2-hexenal, (E)-2-heptenal, and n-undecano. Los mismos compuestos, excepto el α-pineno and (E)-2-octenal, fueron encontrados en las glandulas dorsales y metatoracicas de ninfas y adultos, respectivamente. Extractos de las glandulas exocrinas no evocaron una respuesta antenal de adultos, ni afectaron el comportamiento de ninfas de quinto instar, lo que sugiere que estos compuestos estan probablemente involucrados en funciones de defensas mas que como una feromona de alarma. Key Words: Pentatomidae; Discocephalinae; metathoracic glands; dorsal glands; volatiles View this article in BioOne https://doi.org/10.1653/024.102.0223

The agave weevil, Scyphophorus acupunctatus Gyllenhal, is considered the main pest of Agave tequilana Weber var. 'Azul' (Asparagales: Asparagaceae) in Mexico. In this study, we investigated the population fluctuations of S. acupunctatus for 19 months using 2 sampling methods in blue agave fields in Ahualulco and Amatitan, Jalisco, Mexico. We recorded the direct damage caused by weevils on the sampled agave plants and evaluated the correla- tion between the number of S. acupunctatus captured by pheromone traps and the density of weevils located on plants. In Ahualulco, the highest agave weevil population density (for all developmental stages) was detected in Mar 2008, although the peak of trap captures occurred in May 2009. In Amatitan, the highest agave weevil population density was ob- served in Apr 2009, and the highest number of insects was captured in May and Sep 2009. The mean fraction of necrotic bole tissue caused by the weevils per sampled plant was 75.4 ± 2.1% and 72.6 ± 2.0% in Ahualulco and Amatitan, respectively. In Ahualulco, there was a positive correlation between the number of weevils caught in the pheromone traps and the number of adult weevils on the plants, whereas the number of weevils caught by the pheromone traps at Amatitan was positively correlated with the total number of weevils on the plants. We found that the sex ratio of weevils recovered from agave plants was approxi- mately 1:1 at both experimental sites, and this trend did not vary seasonally; conversely, the sex ratio of captured weevils in pheromone traps was female-biased year-round.

Copitarsia decolora (Guenee) is an important pest of several crops such in Mexico, Central and South America. In addition, this species is a regulatory concern in the USA. In this work, we investigated the influence of trap design, trap height, and trap color on pheromone trap catches of C. decolora males in cruciferous crops. Additionally, we investigated the seasonal dynamics of C. decolara for 3 yr. The water-trap captured a significantly higher number of males compared to the jug trap and the Scentry® Heliothis trap. There were no significant differences between in the number of males captured by traps positioned at 0.5, 1, and 1.5 m above ground level. There was also no an interaction between trap design and trap height. Green water-traps captured more males than red water-traps, however, the catches of red water-traps were intermediate and not significantly different from those captured by yellow, blue, and brown water-traps. A total of 6,978 C. decolora males were captured during the 3 yr of trapping. The overall distribution of trap captures over the season was unimodal, with a distinctive peak in trap catches occurring between Mar and Apr.

The West Indian fruit fly, Anastrepha obliqua (Macquart), is considered one of the most important pests of mango (Mangifera indica L.) and hog plums (Spondias spp.) in Latin America. A better understanding of the role of chemical compounds during the sexual behavior of A. obliqua may be useful to improve the monitoring of this tephritid fruit fly pest. The objectives of this study were: (1) to evaluate the attraction of females and males to live calling males and to Super Q extracts of calling males; (2) to measure the female and males antennal responses to extracts from live calling males; (3) and to identify the compounds emitted by A. obliqua males during calling by gas chromatography-mass spectrometry (GC-MS). Both sexes were attracted to live males and to male extracts. Extracts from males elicited significant antennal responses from both sexes compared to those evoked by the control. GC-MS analyses of the volatile extracts showed that calling A. obliqua males consistently emitted 9 compound...

We investigated the behavioral responses of neonate and mature (6th instar) larvae, and mated females of Estigmene acrea (Drury) (Lepidoptera: Arctiidae) to a range of wavelengths under laboratory conditions. The behavioral responses of E. acrea were determined by means of choice tests, exposing the insects to 2 different wavelengths, ranging from 340–670 nm (ultraviolet to red colors), of the same intensity in selection chambers. Both neonate and mature larvae were significantly more attracted to 380, 400, and 520 nm than to the control wavelength of 570 nm. Because E. acrea is a generalist species that moves between plants to feed, it may be important for a larva to detect and move towards green foliage in preference to the ground or other objects. Mated females were significantly more attracted to the wavelengths of 340, 350, 370, 380, 420 and 460 nm than to the control wavelength. Females may use ultraviolet and blue lights as orientation cues during the searching behavior for oviposition sites.

Host selection and egg laying behavior of wild populations of the mountain white butterfly, Leptophobia aripa (Boisduval), was observed in the presence of a group of host plants (Brassica oleracea L. var. capitata) of varying quality. Host variation was generated by manipulating three crop management variables: fertilization, water, and light. Leptophobia aripa was not indifferent to host quality variation, and showed great ability to evaluate and discern among a group of hosts. A sigmoidal relation was found between egg laying and host plant size. The latter was probably perceived through the host's diameter, or other physical and chemical characteristics related to this attribute. More detailed studies are necessary in order to understand which cues this insect uses to locate its host and which other attributes it evaluates upon deciding to lay eggs. This understanding could allow for the development of agro-ecological alternatives in controlling this insect, considered to be a crop pest in som...

The behavioral and electrophysiological responses of males and females of the Mexican fruit fly Anastrepha ludens (Loew) to guava (Psidium guajava L.) volatiles were investigated in laboratory tests. Males and females were significantly more attracted and landed more often on guava fruits than yellow spheres used as control in the wind tunnel. Also, both sexes were more attracted to Porapak Q extracts of guava than to solvent controls. Gas chromatography-electroantennographic detection (GC-EAD) analysis of the behaviorally active extracts showed that consistently eight and seven compounds elicited antennal response from male and female, respectively. The compounds were identified by gas chromatography-mass spectrometry (GC-MS) as ethyl butyrate, (E)-3-hexenol, (Z)-3-hexenol, hexanol, ethyl hexanoate, hexyl acetate, (Z)-3-hexenyl butyrate and ethyl octanoate. The electrophysiological activity of the identified compounds at three different doses was evaluated with electroantennography (EAG). An ana...

Volatile compounds released by disturbed females of the bethylid wasp Cephalonomia stephanoderis Betrem were collected and analyzed by gas chromatography-mass spectrometry. The origin of volatiles and their behavioral effects on conspecifics were also investigated. The source of the volatile compounds was found to be the head, and more specifically, the mandibular glands. These glands contain skatole as the main volatile component. Behavioral bioassays demonstrated that extracts of parasitoid heads and synthetic skatole evoked the same alarm behavior in this species. The possible function of this chemical is discussed.

We determined seasonal and nocturnal flight activity of Spodoptera frugiperda (J. E. Smith) males with traps baited with pheromone in the coast of Chiapas, Mexico. A total of 3015, 3065, and 838 males were captured in 2000, 2001, and 2002, respectively. Pheromone trap catches decreased approximately 72% during 2002 with respect to 2000 and 2001. One of five experimental sites caught 90% of the total captured. The pattern of trap captures was quite variable among years and sites. In general, the flight activity of S. frugiperda males was seasonal, with two distinctive peaks in trap captures during the year. Males were caught during all hours of scotophase, however, most males were captured during the first 7 h. Highest peak capture was between 1900-2000 h. Trap captures were positively correlated with wind speed and temperature, and negatively correlated with relative humidity. Significantly more males were captured at wind speeds of 100-200 and >200 m/min than at wind speeds of 0-100 m/min.

This paper reports a new record of a moth species, Zamagiria dixolophella Dyar (Pyralidae: Phycitinae) attacking sapodilla (Manilkara zapota van Royen) in Southern Mexico. This is the first report of this species in Mexico. The female genitalia and the last instar larva are described and illustrated.

The West Indian fruit fly, Anastrepha obliqua (Macquart), has been recorded from the USA (Florida and Texas) to South America, including the Caribbean Islands. This is a species of fruit flies that causes serious damage to several eco nomically important fruit crops, such as mango, sapodilla, and guava (Hern?ndez-Ortiz & Aluja 1993). Lures based on organic compounds such as pu trescine, ammonium acetate, or liquid hydrolyzed protein have been used successfully as attracta nts in programs for detection and monitoring of several species of fruit flies (Heath et al. 1997). Volatiles from fruit odors also have been investi gated as attractants for fruit flies (Reynolds & Prokopy 1998; Robacker & Heath 1996; Prokopy & Vargas 1996; Nigg et al. 1994). Recently, Cruz L?pez et al. (2006) showed that both sexes of A. obliqua are strongly attracted to a blend of 9 syn thetic compounds of volatiles of hogplum (Spon dias mombin L.). The combination of nitrogenous lures and fruit odors may improve the catches of A. obliqua, but this approach remains to be inves tigated in field tests. The aim of this paper was to evaluate the response of feral flies of A. obliqua to a synthetic 9-component blend of hogplum vola tiles (S. mombin), in combination with putrescine and ammonium acetate. Field trials were conducted in an unsprayed commercial orchard of mango Cv. Ata?lfo located in Tapachula, Chiapas, Mexico from May to Jun 2006. Multilure traps (Better World Manufactur ing Inc., Fresno, CA) were hung from branches of fruit trees 4 m above the ground, and 15 m apart. The traps were baited with the following treat ments: (1) ammonium acetate (AA) (Suterra LLC, OR, USA) + synthetic blend of S. mombin fruits (SM); (2) putrescine (Pu) (Suterra LLC, OR) + SM; (3) AA + Pu + SM; (4) AA + Pu; (5) SM alone; and (6) hydrolyzed protein (HP) Captor 300 (Pro motora Agropecuaria Universal S.A. de C.V., Mex ico City) used as control. Each trap contained 250 mL of water, and 2 mL of Tween 80 (ICI, Wilming ton, DE), which were added to retain flies, while others traps were baited with 10 mL of the hydro lyzed protein mixed with 5 g of borax dissolved in 235 mL of water per trap. The synthetic blend of S. mombin fruits were prepared as described else where (Cruz-L?pez et al. 2006), and 100 pL of syn thetic blend were loaded in a rubber septum (Sigma-Aldrich, Toluca, Mexico). The rubber septa were put in the lure compartment of the Multilure trap. Each row of trees contained a trap of each treatment, and there were 5 replicates per treatment. Traps were collected every 3 d and the position of traps within each row was rotated The captures of A. obliqua were analyzed by analysis of variance (ANOVA), and means were separated by the Tukey test (a= 0.05). Data were transformed byy0 4 for total flies analysis, and y0 5 for females and males analysis by the Box-Cox family of power transformation (Box & Cox 1964) to stabilize variances before analysis. Data anal ysis was performed with Statistica ver. 6 (Stat Soft, Inc.,Tulsa, OK). In total, 950 adults of A. obliqua were captured in all traps, 615 flies were females, and 335 were males. In addition, traps captured individuals of Anastrepha ludens and Anastrepha serpentina (Wiedemann). We found that the catches were sig nificantly affected by treatment (total flies F = 34.38; df= 5, 20; < 0.001; females F = 45.60; df = 5, 20; < 0.001; males F = 12.66; df= 5, 20; < 0.001). Traps baited with HP, AA + Pu + SM, and AA + Pu caught more females and total flies than the traps baited with AA + SM, Pu + SM, and SM alone. While the traps baited with HP, AA + Pu, and AA + Pu caught more males than the traps baited with AA + SM, Pu + SM, and SM alone. Flies males captures by traps baited with AA + Pu + SM were not significantly different from the catches by traps baited with HP, AA + Pu, or AA + SM. Number of males A. obliqua caught by traps baited with AA + SM was not significantly different from the catches by traps baited with Pu + SM, and SM alone. The traps baited with Pu + SM, and SM alone captured the fewest males (Fig. 1). Our results showed that combination of ammo nium acetate and putrescine with synthetic blend of S. mombin fruits did not improve the captures of both sexes of feral A. obliqua. Similar results to those found in the present study have been re ported in A. ludens, when a blend of 4 synthetic compounds of volatiles of yellow chap?te: 1,8-cin eole, ethyl hexanoate, ethyl octanoate, and hex anol in combination with putrescine, ammonium bicarbonate, and methylamine HCl did not in crease the captures compared with the traps con taining metabolites of amino acids alone (Ro backer 1998). In the course of this experiment, we observed that flies fed on fallen ripe mangoes, and this may affect the response of feral flies to AA + Pu + SM, and SM alone. In semi-natural condi

We analyzed the volatiles emitted by Mexican populations of the female coffee leafminer moth Leucoptera coffeella that were collected in coffee plantations located in the Soconusco region of Chiapas. Our results confirmed previous results that L. coffeella females emitted 5,9-dimethylpentadecane as the major and 5,9-dimethylhexadecane as the minor component. Field response of the coffee leafminer moth to stereoisomers of the major component showed that delta traps baited with (5S,9R)-dimethylpentadecane caught a significantly greater number of coffee leafminer males when compared to those captured by traps baited with (5R,9R)-dimethylpentadecane, (5R,9S)-dimethylpentadecane and the control. The number of coffee leafminer captured by traps baited with (5S,9S)-dimethylpentadecane was not significantly different from the number captured by traps baited with (5R,9R)-dimethylpentadecane. The results are discussed in view of the possibility of using stereoisomers as bait for monitoring the leafminer mo...

Diachasmimorpha longicaudata (Ashmead) is an endoparasitoid of fruit flies reared for augmentative biological control of several species of Anastrepha in Mexico. During the production of D. longicaudata different sizes of parasitoids are produced depending on the host size. Here, we investigated whether host size influences the biological and behavioral parameters of the wasp that emerged under laboratory conditions. Three different sizes of host (small, medium, and large) were used for the experiments. Host size significantly affected the number of parasitoids emerged as greater number of parasitoids emerged from medium size hosts compared to small and large hosts. The ratio of females to males did not differ among the groups. Host body size influenced life expectancy of parasitoid females and males deprived of food, and parasitoids that emerged from large hosts lived longer. In contrast, host body size did not significantly influence the life expectancy of parasitoid females and males provided ...