RESUMO
Diaphorina citri Kuwayama is the primary vector of Huanglongbing, the most devastating disease of citrus. D. citri populations in Puerto Rico were monitored with yellow sticky traps on citrus trees or other psyllid host plants at different elevations, ranging from 10 to 880 m above sea level. Trapping was conducted in March through May of 2013 and 2014 when psyllid populations usually are highest. Population levels of D. citri, based on the trapping data, varied among the sites, and there was a strong trend in both years for decreasing psyllid abundance with increased elevation based on the number of psyllids captured on traps and the proportion of trees shown to be infested. No psyllids were collected at an elevation of >600 m. Reduced populations at higher elevations could be a consequence of differences in temperature, air pressure, oxygen levels, ultraviolet light, or other factors alone or in combination. We discuss our results as they pertain to management of D. citri and Huanglongbing.
Assuntos
Altitude , Citrus , Hemípteros , Insetos Vetores , Animais , Densidade Demográfica , Porto RicoRESUMO
Atemoya is a hybrid between Annona squamosa L. and Annona cherimola Miller (Annonaceae) and has potential to be an important fruit crop in tropical and subtropical areas. A major impediment to fruit production is low fruit set due to inadequate pollinator visits, typically, by beetles in the family Nitidulidae. We used Universal moth traps to monitor the attractiveness of two commercially available Nitidulidae lures in combination with various food attractants, including raw bread dough, apple juice, and malta beverage, a soft drink by-product of the brewing process. The most commonly trapped beetles were, in order of decreasing frequency, Carpophilus dimidiatus (F.), Brachypeplus mutilatus Erichson, Urophorus humeralis (F.) (Coleoptera: Nitidulidae), and Europs fervidus Blatchley (Coleoptera: Monotomidae). All traps, except the unbaited control traps, caught beetles. In a previous study, we found that combining two commercial lures had a synergistic effect on the attraction of these beetle species. In this study, the addition of food attractants increased the number of beetles trapped compared with traps baited with only the commercial lures. Also, food attractants appear to be key in attracting U. humeralis; only one U. humeralis individual of the 206 caught during the experiment was trapped without a food attractant. The variation between the number of beetles caught in traps containing the same treatments was high and may explain the erratic results reported in other studies of pollination in Annona spp. The results are discussed with respect to the use of nitidulid lures and food attractants to increase fruit set in atemoya and other Annonaceae.
Assuntos
Agricultura/métodos , Annona/fisiologia , Besouros/fisiologia , Feromônios/farmacologia , Polinização , Animais , Besouros/efeitos dos fármacos , Porto RicoRESUMO
The corn- and rice-strains of Spodoptera frugiperda exhibit several genetic and behavioral differences and appear to be undergoing ecological speciation in sympatry. Previous studies reported conflicting results when investigating male attraction to pheromone lures in different regions, but this could have been due to inter-strain and/or geographic differences. Therefore, we investigated whether corn- and rice-strain males differed in their response to different synthetic pheromone blends in different regions in North America, the Caribbean and South America. All trapped males were strain-typed by two strain-specific mitochondrial DNA markers. In the first experiment, we found a nearly similar response of corn- and rice-strain males to two different 4-component blends, resembling the corn- and rice-strain female blend we previously described from females in Florida. This response showed some geographic variation in fields in Canada, North Carolina, Florida, Puerto Rico, and South America (Peru, Argentina). In dose-response experiments with the critical secondary sex pheromone component (Z)-7-dodecenyl acetate (Z7-12:OAc), we found some strain-specific differences in male attraction. While the response to Z7-12:OAc varied geographically in the corn-strain, rice-strain males showed almost no variation. We also found that the minor compound (Z)-11-hexadecenyl acetate (Z11-16:OAc) did not increase attraction of both strains in Florida and of corn-strain males in Peru. In a fourth experiment, where we added the stereo-isomer of the critical sex pheromone component, (E)-7-dodecenyl acetate, to the major pheromone component (Z)-9-tetradecenyl acetate (Z9-14:OAc), we found that this compound was attractive to males in North Carolina, but not to males in Peru. Overall, our results suggest that both strains show rather geographic than strain-specific differences in their response to pheromone lures, and that regional sexual communication differences might cause geographic differentiation between populations.
Assuntos
Atrativos Sexuais/farmacologia , Comportamento Sexual Animal/efeitos dos fármacos , Spodoptera/fisiologia , Análise de Variância , Animais , Relação Dose-Resposta a Droga , Geografia , Modelos Lineares , Masculino , América do Norte , Oryza/parasitologia , Porto Rico , Atrativos Sexuais/química , América do Sul , Especificidade da Espécie , Spodoptera/efeitos dos fármacos , Zea mays/parasitologiaRESUMO
McPhail-type traps baited with ammonium acetate and putrescine were used to monitor populations of Anastrepha obliqua (Macquart) and Anastrepha suspensa (Loew) in two orchards with hosts of these flies (mango, Mangifera indica L., and carambola, Averrhoa carambola L.), as well as in forest fragments bordering these orchards. Contour maps were constructed to measure population distributions in and around orchards. Our results indicate that Anastrepha populations are focused around host fruit in both space and time, that traps do not draw fruit flies away from hosts, even when placed within 15 m of the host, and that lures continue to function for 6 mo in the field. The contour mapping analyses reveal that populations of fruit flies are focused around ovipositional hosts. Although the trapping system does not have a very long effective sampling range, it is ideal, when used in combination with contour analyses, for assessing fine-scale (on the order of meters) population distributions, including identifying resources around which fly populations are focused or, conversely, assessing the effectiveness of management tools. The results are discussed as they pertain to monitoring and detecting Anastrepha spp. with the McPhail-type trap and ammonium acetate and putrescine baiting system and the dispersal of these flies within Puerto Rico.
Assuntos
Distribuição Animal , Ecossistema , Frutas/crescimento & desenvolvimento , Controle de Insetos , Tephritidae/fisiologia , Agricultura , Animais , Mangifera/crescimento & desenvolvimento , Densidade Demográfica , Porto Rico , Especificidade da EspécieRESUMO
Atemoya, a hybrid between Annona squamosa (L.) and A. cherimola Miller (Annonaceae), has potential to be a major fruit crop in tropical and subtropical areas. A major setback to fruit production throughout the world is low fruit-set because of inadequate pollinator visits, typically Nitidulidae beetles. We identified beetle visitors to atemoya flowers in an orchard in Puerto Rico and used Universal moth traps to monitor the attractiveness of two commercially available Nitidulidae lures. The most common visitors to atemoya flowers were an unidentified Europs species (Coleoptera: Monotomidae), followed by Loberus testaceus (Coleoptera: Erotylidae), neither of which have been previously reported as visitors to Annona flowers. The commercial lures attracted few or no beetles when used separately, but attracted a large number of beetles, especially Carpophilus dimidiatus (Coleoptera: Nitidulidae) and Europs, when used in combination. This attraction is synergistic and increases with dose at the doses assayed (0-4 lures), and decreases over time with >50% of trap captures occurring in the first week and no beetles collected after 5 wk. This is the first report of aggregation pheromone lures in nitidulids acting synergistically to attract other species, including beetles not in the Nitidulidae. The results are discussed as they pertain to increasing fruit set, as well as the potential for altering fruit size and shape in atemoya.
Assuntos
Annonaceae , Comportamento Animal/efeitos dos fármacos , Besouros/efeitos dos fármacos , Feromônios/farmacologia , Polinização , Animais , Porto RicoRESUMO
Fall armyworm, Spodoptera frugiperda (J.E. Smith) (Lepidoptera: Noctuidae), is an important agricultural pest that is endemic to Puerto Rico and the rest of the Caribbean islands. Relatively little is known about the population movements of fall armyworm in the Caribbean and the magnitude of genetic interactions, if any, with populations from North, South, and Central America. To address this issue, a novel method involving mitochondrial haplotype ratios currently being used to study the migration of fall armyworm in North America was applied to populations in Puerto Rico. The results indicate limited interactions between Puerto Rico fall armyworm and those from Brazil or Texas but the potential for significant exchanges with populations in Florida.
Assuntos
Haplótipos , Mariposas/genética , Animais , Brasil , Demografia , Florida , Mariposas/fisiologia , Porto Rico , TexasRESUMO
Twenty fruit species representing 12 families were collected from various regions in western Puerto Rico and monitored for the emergence of Anastrepha spp. pupae. We collected 14,154 tephritid pupae from 16 fruit species representing 10 families. The relative infestations of these fruits (pupae per kilogram of fruit) were recorded. Recorded host ranges were not in complete agreement with those reported in the literature. This host-use pattern should give pause to regulators of fruit importation and exportation that base their decisions on literature from regions other than those of immediate interest to them. We recovered the braconid parasitoid Utetes anastrephae (Viereck) from tephritid pupae collected from Mangifera indica L., Spondias mombin L., Psidium guajava L., Chrysobalanus icacos L., Terminalia catappa L., and Garcinia intermedia (Pittier) Hammel. We collected one specimen of the parasitoid Doryctobracon aerolatus (Szepligeti) from the west coast (Añasco), which had not been previously reported in Puerto Rico. We present a preliminary phenology of what are probably the primary fruit hosts of the Anastrepha spp. of Puerto Rico. We also present the first report of Garcinia intermedia (Pittier) Hammel and Coffea arabica L. as reproductive hosts of A. suspensa.