Colony collapse disorder of honey bees, Apis mellifera L., is a global problem with no conclusive cause yet accepted. A previous U.S. Army study identified a DNA virus, invertebrate iridescent virus (IIV-6), and two microsporian pathogens, Nosema apis Zander 1909 and Nosema ceranae Fries et al. 1996, in bee samples from a collapsing hive. A PCR-based study using limited samples failed to confirm IIV-6 in collapsing colonies, causing the finding to be questioned. Here we demonstrate that honey bees are very susceptible to the virus. We observed viral inclusion bodies in the cytoplasm of honey bee brood previously inoculated with IIV-6. Electron microscopy revealed massive numbers of viral particles in cells at 3 days post-inoculation. Viral factories and paracrystalline arrays of particles ∼125 nm in diameter were observed. Few cells were spared infection, indicating that honey bee larvae are very susceptible to IIV-6 and most tissues are infected.

Tick-borne diseases are increasing in the United States, with regional need to understand how knowledge of ticks translates into preventative behavior among specific occupational groups. Little is known regarding what livestock producers know about ticks and their perceived personal and herd-based risk despite being one of the largest agro-industries in the United States. Using a nonprobability convenience sampling protocol, 183 beef producers representing 65% of the counties in Oklahoma completed a 15-question survey focused on knowledge of ticks and perceived risks ticks pose to their cattle and themselves, their methods of prevention (personal and their cattle), and sources of information. Most producers thought ticks were not a major problem for their cattle (58%), themselves, their families, and those who worked for them (66%). Most were personally concerned about spotted fever group rickettsiosis (79%) but had never heard of ehrlichiosis (9%). Eighty-five percent used at least one type of personal protective behavior, and 86% used at least one source of information for issues with ticks on their cattle. As the first published tick-focused survey involving livestock producers in the United States, it is apparent that beef producers in the central region are cognizant of ticks on their cattle and perceive ticks to be a risk on some level. However, increasing their knowledge of all areas of ticks and tick-borne pathogens, especially preventative measures for humans and cattle, is needed.

The annual infestation pattern of R. sanguineus sensu lato (Latreille) was studied for dogs in a tropical sub-humid region of Mexico. Infestation was monitored for a year at five veterinary clinics in different parts of the urban area of Colima City, Mexico. Dogs were considered positive for infestation when at least one specimen of any stage of the parasite was identified by physical search. R. sanguineus occurred throughout the year, with 21.4% average (446/2083; 95% C.I. 19-23) and infestation ranging from 17% in January to 29% in May. Seasonal distribution was homogeneous: spring 22.2% (96/432), summer 21.5% (103/477), autumn 21.4% (132/616), and winter 20.6% (115/558). No correlation was found between seasonal prevalence and weather during a season (p > 0.01). Tick specimens and all parasitic stages were found throughout the year. There were more larvae in March to June, September, and November; nymphs in March to May and December; and more adults in January, February, July, and October. Activity of each stage of ticks where dogs are always available indicated that R. sanguineus develop at least three generations per year.

The impact of natural and simulated rainfall and wind on sugarcane aphid, Melanaphis sacchari (Zehntner), on sorghum, Sorghum bicolor (L.) Moench, was studied near Río Bravo, Tamaulipas, northeastern Mexico. In 11 events, natural rainfall intensity ranged from 15 to 51 mm per hour; average winds from 5 to 37 km per hour; and maximum wind (gusts) from 10 to 107 km per hour. Natural rain caused an average reduction of 32% adults, 13% nymphs, and 14% total (adults + nymphs) after 30 minutes; however, 5 days later, aphid abundance increased an average of 14% (range -55 to +93%). Natural rain caused only an average of 0.6% loss of parasitoid mummies of braconid Lysiphlebus testaceipes (Cresson). A rain simulator was designed to test the effects of artificial rainfall (40 mm per 15 minutes), constant wind (20 km per hour), and wind gusts (70 km per hour, 20 seconds every 2 minutes) during 15, 30, 45, and 60 minutes. After 60 minutes in the rain simulator, 77% of M. sacchari survived with rain alone, 44% with rain + constant wind, 34% with rain + wind gusts, and only 22% with rain + constant wind + wind gusts. Combination of rain and wind was more important than rainfall itself, particularly because M. sacchari feeds underneath the leaves, and disturbance produced by wind greatly reduced aphid survival. Multiple regression models well explained (R² > 0.95) the association of M. sacchari survival (y) with rain and wind independent variables (x_n) for natural, simulated, and combined (natural + simulated) conditions.

Survival of dislodged sugarcane aphid, Melanaphis sacchari (Zehntner), adults and nymphs was studied in pots with four soil moisture treatments: (1) 25% moisture; (2) 25% moisture + spray (30 ml distilled water every 2 minutes); (3) flooded; and (4) dry. Survival of M. sacchari in treatments 1-4 was 67, 38, 8, and 59%, respectively. Survival of adults was significantly greater than nymphs in treatments 2 and 4, with no difference in treatments 1 and 2. Maximum M. sacchari walking speed averaged 9.5 mm per minute; regardless of soil condition, walking speed did not differ significantly between adults and nymphs, but aphids were slowest on dry soil. This study suggested that dislodged M. sacchari aphids can return and reinfest plants, even at the worst scenario with floods.

Plant damage and yield responses to three infestation levels (0, 1, and 10x) of biotype RWA2 Russian wheat aphid, Diuraphis noxia (Kurdjumov), were compared in winter wheat, Triticum aestivum L., during the 2010-11, 2011-12, and 2012-13 growing seasons at two sites in eastern Colorado. Wheat lines contained either no resistance gene (Yuma), Dn4 resistance (Yumar), or the Dn7 resistance gene (CO08RWA050). Fewer Russian wheat aphids and symptomatic tillers were on CO08RWA050 at any infestation. Yuma and Yumar tillers had an average of seven times more aphids present than CO08RWA050. Yields decreased as infestation increased in Yuma and Yumar, but yield was not less in CO08RWA050 at any infestation level. Kernel weights of Yuma and Yumar, but not CO08RWA050, were less with greater infestation. Data from the study suggested that resistance conferred by the Dn7 gene would be effective in reducing Russian wheat aphid abundance, and ultimately benefit wheat producers during outbreak years.

The possible role of pollinators enhancing soybean production has been an ongoing topic of study. The effect of flower visitation, especially by honey bees, Apis mellifera L., in this self-pollinated crop has resulted in no benefit increasing soybean yield, or at times a significant impact on grain production, differences that might be caused by the influence of multiple field condition variables. In this study, an experimental design that excludes insects from soybean plants during the ∼20-day flowering period was used. Results indicated that he number of pods per plant, seeds per pod, and grain yield were not different in plants covered with mesh that prevented insect visitation to flowers, compared with adjacent soybean plants not covered. The single-season studies showed that despite a large number of active honey bee hives 25-50 m away from the evaluated soybean plants, the insects rarely entered the fields, and those that did, spent no time foraging, even when more than 5 million soybean flowers per hectare were available at a very short distance from their hives.

Field-evolved resistance of fall armyworm, Spodoptera frugiperda (J.E. Smith) (Lepidoptera: Noctuidae), to the bacterium Bacillus thuringiensis (Bt) has been reported worldwide as one of the most serious threats to the sustainability of Bt maize crop. Therefore, it is important to assess the magnitude of adult survival and the possibility of cross-resistance of fall armyworm neonates exposed to Bt proteins. In this study, bioassays were used to examine susceptibility of two field-collected Cry1Fa-resistant strains of fall armyworm from Puerto Rico (456RR, 512RR) and their crosses with a susceptible strain (Monsanto SS) (456SR-RS, 512SR-RS). LC₅₀ values varied in both Cry1Fa-resistant strains and in their backcrosses with the susceptible strain. The two RR strains were more tolerant to Cry1Fa and Cry1Ac proteins in earlier instars of development than were their crosses. Greater survival to the adult stage was obtained in the 512 RR strain and their RS-SR crosses when exposed to all concentrations of Cry1Ac and 1Fa. Survival to adult in the 456 RR was much greater when exposed to Cry1Fa than to Cry1Ac. Adults of 456 RR and their crosses survived only when exposed to the lowest concentrations of Cry1Ac. Our data confirmed great resistance to Cry1Fa and Cry1Ac in S. frugiperda larvae from Puerto Rico. However, based on the larvae that survived the 7-day diet bioassay and developed to pupae and adult maturity on regular diet, their LC₅₀ values were less for both resistant strains and their crosses.

An alternative to management of agricultural pests is use of insecticides obtained naturally; the approach is a feasible alternative sustainable in an agricultural system. Argemone mexicana L. (Papaveraceae) is a plant with toxin that repels or kills insect pests, but few studies focused on damage the insecticide causes natural enemies. The objective of the study was to determine the effect by ingestion of plant extract with a base of A. mexicana on biological parameters and parameters of the life table of Chrysoperla carnea (Stephens) (Neuroptera: Chrysopidae), under laboratory conditions. A. mexicana extract diluted in different solvents slightly affected biological parameters without affecting the intrinsic rate of growth. Mortality increased during susceptible stages of the predator, which inferred stage of development would be affected when the predator consumed prey treated with A. mexicana. More than 50% were killed by some treatments and commercial insecticide imidacloprid evaluated in the study.

The aim of the study was to select native strains of Beauveria bassiana with toxic activity against Aedes aegypti (L.). For the bioassays, third-instar larvae of the mosquito were put into 200-ml plastic containers inoculated at an initial concentration of 1 × 10⁶ conidia/ml of 17 strains of B. bassiana. The most-pathogenic strains were selected, and HIB-10 and HIB-4 at different concentrations (1.30 × 10⁴, 1.30 × 10⁵, 1.30 × 10⁶, and 1.30 × 10⁷ conidia/ml) were used to determine LC₅₀ and LT₅₀. For HIB-10, HIB-4, and GHA strains, the LC₅₀ was 1.37 × 10⁶, 5.87 × 10⁵, and 4.90 × 10⁵ conidia/ml, while LT₅₀ was 7.2, 8.3, and 8.5 days, respectively.

Strains of Beauveria from different areas of Nuevo Leon State were isolated, characterized morphologically, morphometrically, and enzymatically, and evaluated against yellow mealworm, Tenebrio molitor L. (Coleoptera: Tenebrionidae), in a laboratory. Twenty-four soil samples were collected. Greater wax moth, Galleria mellonella (L.) (Lepidoptera: Pyralidae), larvae were used as bait. Solid media were used to estimate the production of extra-cellular fungal enzymes. Fifty-eight percent of the soil samples were positive for entomopathogenic Beauveria sp. The activity of strains varied for all enzymes evaluated (proteases ranged from 20.6 to 39.8, chitinases 25.6 to 40.8 and lipases 65.0 to 74.8 mm), as did the number of insects killed (30.0 to 75%). Large amounts of native entomopathogenic Beauveria sp. were found with greater sensitivity than commercial GHA strain against mealworm beetles, with possible better biological control against agricultural pests in Mexico.

Huanglongbing disease caused by the bacterium Candidatus Liberibacter is transmitted from infected to healthy plants by the Asian citrus psyllid, Diaphorina citri Kuwayama. Infectivity by conidia of five strains of Hirsutella citriformis Speare applied by contact was evaluated in field bioassays against D. citri adults. Bioassays were in three orchards of Persian lime (Citrus aurantiifolia (Christm. et Panz.) Swingle var. latifolia Yu. Tanaka) and one Mexican lemon (Citrus aurantiifolia Swingle) orchard at Chiapas, Campeche, Quintana Roo, and Colima states in Mexico. Treatments remained bagged on citrus trees in the field for 21 days after application. The five strains were pathogenic to the Asian citrus psyllid; CHE-CNRCB 339 and INIFAP-Hir-2 strains killed the most (74.1 and 68.3%, respectively). Most mycosis (71.1%) was by CHE-CNRCB 339. Preliminary results in the field confirmed the potential of H. citriformis to control Huanglongbing in Mexico.

Refuge sites are critical for survival of terrestrial arthropods during the dry season in tropical dry forests. Ball moss, Tillandsia recurvata L. (Bromeliaceae), is a refuge site in seasonally tropical dry forests of Central Mexico, although few studies have examined the role of T. recurvata as a microhabitat of arthropods during unfavorable periods. The objective of the study was to catalog species richness and seasonal population dynamics of arthropods using T. recurvata as a refuge site in a dry tropical forest in the State of Querétaro in Central Mexico. In total, 4,319 arthropods from 2,059 samples of T. recurvata were collected during the study. Of the samples, 33 families, 15 orders, and two classes of Arthropoda were identified. Orders of Insecta were Coleoptera, Dermaptera, Diptera, Hemiptera, Hymenoptera, Isoptera (Blattodea), Lepidoptera (larva), Orthoptera, Psocoptera, and Thysanoptera. Arachnida found were Acari, Araneae, Opiliones, and Pseudoscorpionida. Ecological factors of host tree species and location in a tree were not significantly related to abundance of any arthropod taxa. Significant relationship was found between the diameter and weight of T. recurvata and the number of individuals of only three insect categories -- Coleoptera and Heteroptera with diameter, and Auchenorrhyncha with weight and diameter. Various benefits that T. recurvata are postulated to provide to arthropods include microhabitats of greater humidity and escape from predators. Results, in general, suggested T. recurvata augments the quantity and/or quality of habitat in tropical dry forests that might increase arthropod survival and enhance resilience to disturbances and local extinctions, among other benefits.

Because of expanding urban areas and subsequent changes in land cover, elucidating the role of preserving biodiversity in heterogeneous urban green spaces in city scapes is necessary. Alpha, beta, and gamma diversity of ant assemblages were analyzed in a heterogeneous urban green space in the highland city of Tlaxcala in central eastern Mexico. Ant and habitat characteristics were sampled during hot and rainy seasons of 2017 in an urban green space divided into nine sections. In total, 842 individuals of 21 species, 12 genera, nine tribes, and four subfamilies were collected. Sections with more complex habitat structure had fewer and more dominant species, whereas those with simple habitat structure had greater number and evenness of species. Compositional diversity varied significantly among the sampled sections because of much species turnover and great contribution of beta diversity to gamma diversity. The value of the studied urban green space for ant diversity resulted from much turnover of species. Promotion of heterogeneity in urban green spaces in city scapes might be an important strategy for conserving biodiversity as well as ecosystem services provided in and near highland cities.

The invasive spotted-wing drosophila, Drosophila suzukii (Matsumura, 1931), affects fruit with a thin epidermis and causes great loss of production. In Mexico, it is regulated because of its economic damage. Relevance of the sterile insect technique has been analyzed for integrated pest management (IPM) against D. suzukii through study of effects of irradiation doses on control. Possible effect of irradiation at 200 Gy with Cobalt-60, sex, and condition (wild and reared on artificial diet) on wing morphology were analyzed by geometric morphometry analysis. No effect on wing morphology by irradiation was observed, however, significant differences were found in the centroid size of wild females compared with irradiated and non-irradiated females fed artificial diet (F_147,2 = 67.45, P < 0.0001), and they had no significant difference (F_144,2 = 0.81, P = 0.4477) in Procrustes distances. Wild males had significant differences in centroid size (F_147,2 = 59.55, P <0.0001) and Procruste distances (F_144,2 = 3.49, P = 0.0330) compared to irradiated and non-irradiated males fed artificial diet. Changes in the wing of D. suzukii were more related with diets of insects in immature stages. Complementary studies on artificial diets are suggested to produce insects with dimensions similar to wild specimens.

A new Nearctic species of Duretophragma Borkent fungus gnat was discovered in a mixed pine and hardwood forest in the eastern Lower Peninsula of Michigan. Duretophragma collina Taber is the third species of its genus known from North America. Many males and one female were collected. No immature form has been discovered.

A new species of Zapatella Pujade-Villar and Melika, Z. polytryposa Pujade-Villar and Fernández-Garzón n. sp., from Mexico is described here. It is an agamic form, potentially dangerous, killing branches of Quercus crassipes Humb. and Bonpl. Diagnostic data, distribution, and biology of the new species are provided. Principal morphological characters of the new species are described and illustrated. The damage also was described. Zapatella is mentioned for the first time for Mexico; previously, it was known from the USA (six species), Costa Rica (one species), and Colombia (seven species).

Se estudió bajo condiciones controladas en invernadero el índice de atracción de adultos y preferencia de oviposición de Bemisia tabaci Mediterranean en ocho poblaciones criollas (Solanum lycopersicum) y catorce poblaciones silvestres (S. lycopersicum var. cerasiforme) de tomate, así como la relación de estos parámetros de resistencia tipo antixenosis con la densidad de tricomas no-glandulares que son características que pueden prevenir la infestación de este insecto. Cinco poblaciones silvestres y tres criollas mostraron una resistencia alta, y tres poblaciones criollas y una silvestre tuvieron una resistencia intermedia. El resto de las poblaciones y un cultivar comercial fueron altamente susceptibles porque fueron significativamente más atraídos por los adultos y preferidos para la oviposición de este insecto, indicando que existen diferentes niveles de resistencia tipo antixenosis. El número de tricomas no-glandulares no se correlacionó con ninguno de los parámetros de resistencia, indicando que no existe relación entre estos parámetros y que la resistencia observada en estos genotipos puede ser debida a otros factores como compuestos volátiles que repelen a este insecto. Estas poblaciones de tomates con diferentes niveles de resistencia tipo antixenosis pueden utilizarse para producir cultivares de tomate menos atractivas para la infestación de este insecto y como barreras físicas que rodeen los cultivos de tomate para repeler las infestaciones de B. tabaci Mediterranean.

Se realizó un estudio de campo con el objetivo de evaluar la respuesta de Dendroctonus frontalis y Dendroctonus mexicanus a dos atrayentes semioquímicos comerciales (1) frontalina + α-pineno, (2) frontalina + una mezcla de α-pineno y β-pineno + endo-brevicomina, y conocer la abundancia relativa de estas especies en un gradiente altitudinal. La abundancia de D. frontalis y D. mexicanus fue diferente en respuesta a los dos atrayentes. Frontalina + α-pineno y β-pineno + endo-brevicomina atrajo 30 veces más escarabajos descortezadores. Aunque ambas especies se recolectaron en los puntos de muestreo, D. frontalis fue más abundante entre 1,672 a 2,040 m snm, y D. mexicanus entre 2,291 a 2,530 m snm. Estos resultados tienen implicaciones para el monitoreo y el trampeo masivo de estos insectos, pues por cada 100 especímenes que se capturen en trampas cebadas con frontalina + α-pineno, se capturarían 3,000 especímenes si se utiliza frontalina + endo-brevicomina + mezcla de monoterpenos, lo que significa 30 veces más el tiempo y el esfuerzo necesario para la identificación y conteo de los insectos. Por lo tanto, si el objetivo es detectar la presencia de D. frontalis y D. mexicanus, o determinar los periodos de vuelo de estas especies en un área de interés, es suficiente utilizar frontalina + α-pineno; en cambio, si se pretende complementar las actividades de saneamiento para el control de brotes en etapa inicial, o evitar la dispersión de insectos de trocería infestada en centros de acopio, es más adecuado el usar frontalina + endo-brevicomina + mezcla de monoterpenos, con los debidos cuidados para evitar incrementar los ataques.

En esta investigación evaluamos la actividad insecticida de una fracción acuosa de tallos de Serjania schiedeana Schltdl. (Sapindaceae) (FASs), a concentraciones de 250, 500, 1,000, 1,500, y 2,000 ppm, en laboratorio e invernadero en plantas de maíz sobre larvas neonatas de Spodoptera frugiperda Smith (Lepidoptera: Noctuidae). Los resultados de los bioensayos de laboratorio mostraron que a los 14 días el FASs a 250 y 1,500 ppm inhibió 50 y 20% el peso larval del insecto. La FASs en todas sus concentraciones ocasionó una mortalidad larval superior a 50% y una mortalidad total de larvas + pupas del 100%, excepto a 500 ppm. En el invernadero, a partir del día siete las plantas de maíz asperjadas con FASs a 250 y 2,000 ppm disminuyeron el daño de las larvas en más del 18%. Un perfil fitoquímico de la FASs, resultó positivo para alcaloides, flavonoides y taninos, estos compuestos podrían tener relación con el efecto insecticida contra S. frugiperda. Los resultados demuestran que la FASs puede ser considerada para el desarrollo de nuevos insecticidas botánicos y posiblemente ser considerados en el control integrado de plagas.

La producción de mango en México es de gran importancia económica. Uno de los problemas que afecta su producción son el ataque de las plagas, principalmente la escama blanca (Aulacaspis tubercularis Newstead). Se evaluaron aplicaciones de cuatro sustancias para controlar a la escama blanca, de los cuales el aceite mineral, azufre, y spinosad fueron más eficientes en el control de la escama blanca que imidacloprid, los cuales son productos de menor impacto al medio ambiente y a la salud humana.

Se estudió la diversidad de Braconidae en limón mexicano [Citrus aurantifolia Christm. (Swingle)] en Tecomán, Colima, México, identificando 13 subfamilias, 24 géneros, y 54 morfoespecies. La subfamilia con mayor número de géneros y especies fue Doryctinae y los géneros con más especies fueron Heterospilus Haliday, Opius Wesmael, y Bracon Fabricius. Se recolectó 76% de la riqueza real local de acuerdo al estimador ACE, por lo que el esfuerzo de colecta puede considerase representativo, pero también indica que aún es necesario más trabajo de campo para recolectar las especies esperadas en el área de estudio.

En México se detectó por primera vez a Melanaphis sacchari (Zehntner) en 2014 en el estado de Tamaulipas en sorgo, donde causó graves pérdidas a los agricultores. Ante esta problemática el gobierno federal implementó la “Campaña Nacional Contra el Pulgón Amarillo”, con la finalidad de diseñar un programa de manejo integrado de plagas, donde el control biológico es un elemento importante. Se estudió la fluctuación poblacional del pulgón amarillo y se identificaron sus depredadores en parcelas comerciales de sorgo con manejo tradicional realizado por productores en el estado de Puebla. En Aguacomulican se presentó el mayor promedio de ninfas de M. sacchari superando el umbral de daño económico (55 ninfas/hoja) en los primeros muestreos (44 días después de la siembra). Atzala superó el umbral 53 días después de la siembra, y en Calmeca no se superó el umbral en todo el ciclo de muestreo. Los depredadores Coccinellidae (139 individuos) más abundantes fueron Hippodamia convergens (Guérin-Méneville) y Cycloneda sanguinea (L.). Los Syrphidae (87) les siguieron en abundancia destacando Allograpta exotica (Wiedemann), Toxomerus politus (Say), y Allograpta obliqua (Say). Chrysopidae (44) tuvo el tercer lugar de abundancia con la especie Chrysoperla externa (Hagen).

Los parasitoides son importantes controladores naturales de áfidos, sin embargo, existen hiperparasitoides que podrían afectar su desempeño. En este trabajo se reporta para el estado de Morelos a Lysiphlebus testaceipes (Cresson) como un parasitoide primario del pulgón amarillo, Melanaphis sacchari (Zehntner), en sorgo (Sorghum bicolor (L.) Moench) y a tres hiperparasitoides: Pachyneuron aphidis (Bouché); Alloxysta sp. (Föster), y Syrphophagus aphidivorus (Mayr). De 1,040 pulgones momificados recolectados emergieron 210 Lysiphlebus testaceipes adultos, 101, Pachyneuron aphidis, 87 Alloxysta sp., y 28 Syrphophagus aphidivorus.

En mayo de 2017 se estableció un cultivo experimental de quinua (Chenopodium quinoa Wild.) en el centro de México. Durante el desarrollo vegetativo se observaron hojas infestadas por larvas de minador de 2-10 larvas/hoja. Las larvas se incubaron para esperar emergencia de adultos. Los especímenes se determinaron como Pegomya exilis hernandezi (Snyder) (Diptera: Anthomyiidae). De acuerdo con la información científica recabada hasta la fecha, este constituye el primer registro de esta especie en el cultivo de quinua.