The symbiosis between fungi and leaf-cutting ants (Hymenoptera: Formicidae) has aroused the interest of researchers about the mechanism used by ants to select plants. The nutritional needs of the fungus garden, and the absence of potentially deleterious substances from plants, are criteria for selection by foraging workers. This is supported by behavioral experiments using fungicide with baits (citrus pulp) or forage plants highly accepted by leaf-cutting ants. The fungus garden is hypothesized to emit a volatile semiochemical in response to a fungicide, which informs ants that a plant is unsuitable for its growth. The objectives of our study were to identify the volatile compounds released by the fungus garden of leaf-cutting ants in response to a fungicide, as well as to determine the behavioral response of workers to healthy and unhealthy fungus gardens. The results showed no difference in the proportion of volatile compounds released by either healthy or unhealthy fungus gardens. Analysis of the responses of ants to healthy or unhealthy fungus gardens in a dual-choice experiment revealed a strong attraction to the fungus garden, regardless of its health status. We therefore conclude that no volatile semiochemicals are emitted by the fungus garden due to the action of deleterious substances.

The high diversity within a guild of Pseudacteon Coquillet (Diptera: Phoridae) parasitoid flies hosted by the red imported fire ant, Solenopsis invicta Buren (Hymenoptera: Formicidae), may be based on several niche axes, including host size specialization, host location cues, climatic responses, and tolerances. The recently described species, Pseudacteon obtusitus Plowes, Folgarait, and Gilbert (Diptera: Phoridae), is one of the smallest species in this group (with a thorax width of only 0.3 mm), and appears to locate ant hosts on foraging trails as well as at nest disturbances. Here we examine the ecology, phenology, and development of this parasitoid at sites in Corrientes, Argentina. Pseudacteon obtusitus has 2 seasons of peak abundance, and exhibits low tolerance for cold temperatures or extended cold periods. It preys on the smallest ant workers (typically 0.6 mm head width) independent of the ant size offered, and has a male biased sex ratio (mean 2.78:1). Developmental times ranged from 35 d at 27 °C to 44 d at 22 °C. This species holds interest for inclusion among the multi-species assemblage of parasitoid flies considered for biological control of S. invicta in its invasive range in North America.

Detection of the Mediterranean fruit fly (medfly), Ceratitis capitata (Wiedemann) (Diptera: Tephritidae), relies heavily on traps baited with the male attractant trimedlure. This lure is dispensed from solid polymeric plugs (2 g a.i.) that are changed out every 6 wk, because beyond this interval their attractiveness drops significantly below that of fresh lure. Existing data suggest that plugs loaded with 4 g of trimedlure may have longer attractancy, which would allow for longer servicing intervals with associated reductions in material and labor costs. The objective of the present study was to gather additional data on the effectiveness of plugs having trimedlure loadings greater than 2 g. In 4 field experiments conducted in Hawaii, the capture of male medflies was compared over 10 or 12 wk periods between control traps baited with 2 mL fresh liquid trimedlure on a cotton wick and treatment traps baited with aged plugs containing 2 to 4 g of the lure. In all experiments, 6-wk-aged plugs, regardless of the specific loading, attracted similar numbers of males as the fresh liquid lure. Conversely, in 3 of the 4 experiments, plugs aged for 10 or 12 wk attracted significantly fewer males than the fresh lure. The performance of plugs aged 8 wk was inconsistent, showing similar attractiveness as fresh lure in certain cases but not others. Based on these findings, we conclude that, counter to our expectations, the use of 4 g trimedlure plugs would not allow effective trapping over longer inter-servicing intervals.

The temperature-driven development rates and longevity times of Psyllaphycus diaphorinae Hayat (Hymenoptera: Encyrtidae), a hyperaparasitoid of Tamarixia radiata (Waterston) (Hymenoptera: Eulophidae) and Diaphorencyrtus aligarhensis (Shafee, Alam & Agarwal) (Hymenoptera: Encyrtidae), 2 primary parasitoids of Asian citrus psyllid, Diaphorina citri Kuwayama (Hemiptera: Liviidae), were quantified. Development times and longevity were investigated at 6 average daily temperatures (15, 18, 20, 25, and 32 °C) that either were constant or fluctuated over 24 h. Thermal performance curves for egg-to-adult development of P. diaphorinae reared on D. aligarhensis were characterized using 1 linear and 2 nonlinear degree-d models (i.e., Ratkowsky and Performance-2). Daily thermal fluctuations had significant effects on development rates and longevity of P. diaphorinae adults. Psyllaphycus diaphorinae reared under fluctuating profiles completed development more slowly (20, 25, and 32 °C), and survived longer (18–32 °C) than those reared under constant profiles with equivalent mean temperatures. In addition, P. diaphorinae emerged from fluctuating but not constant profiles at 15 °C. Estimates of thermal constants (i.e., degree-d to complete development) predicted by the linear model were 36% lower for the constant temperature regimen than the fluctuating temperature regimen. Nonlinear and linear model estimations of the theoretical lower and upper thermal thresholds ranged between –3.7 to 11.9 °C and 33.7 to 34 °C, respectively. The development rate of male and female P. diaphorinae was most favorable at 30 °C. These results demonstrate the significant effects of average temperatures and daily temperature variations on P. diaphorinae life history.

Cricotopus lebetis Sublette (Diptera: Chironomidae) is an aquatic insect adventive in Florida. Evidence from previous studies suggest the insect may have value as an augmentative biological control agent for hydrilla, Hydrilla verticillata (L.f.) Royle (Hydrocharitaceae), but there are gaps in knowledge of the biology and life history traits. To increase understanding of this insect, this study was comprised of 3 experiments. In the first experiment, we investigated the productivity and survival rate of C. lebetis across 6 generations by analyzing our colony data. Then the effect of intraspecific competition on the rates of pupal and adult eclosion was studied by monitoring hydrilla tips in test tubes with varying numbers of larvae. Finally, the level of hydrilla stem tip damage caused by a C. lebetis larva was determined by monitoring tip damage following feeding of a known number of larvae on a standardized number of hydrilla tips. The first experiment revealed the average survival rate of C. lebetis from egg to adult was 16.4%. Approximately a third of the females (30.2%) oviposited. The egg masses had an average of 154.5 eggs per egg mass and an 83.7% fertility rate. Investigation of intraspecific competition revealed pupation and adult eclosion was highest with 1 C. lebetis larva per hydrilla stem tip. Evaluation of the impact of C. lebetis larvae feeding on hydrilla showed stem tips in treatments with C. lebetis larvae experienced 38% higher damage compared to stem tips in control treatments. Overall, this study provided valuable information useful in improving the mass rearing of C. lebetis and predicting the damage caused by C. lebetis. For example, for efficient mass rearing, an average of 1 larva per hydrilla tip should be maintained with the remainder of eggs being used for augmentative releases.

Social wasps find prey mainly using olfactory cues when foraging. Flight area and the ability to return to the nest after this activity was studied for the predatory wasp Polistes lanio lanio (Fabricius) (Hymenoptera: Vespidae) using mark-recapture techniques. One hundred workers of this wasp were removed from 20 nests (5 per nest), marked on the mesothorax, and released after 2 d. Wasps were released at different times and distances to reduce memorization of the flight path. We determined that P. lanio lanio workers' hypothetical foraging area was 13.2 km² based on their greatest return capacity to nests.

The Bemisia tabaci (Gennadius) (Hemiptera: Aleyroridae) sibling species group is comprised of genetic variants defined by biological differences or a fragment of mitochondrial cytochrome oxidase I gene sequence (mitotype) that allows for phylogeographic affiliation. Some mitotypes may cause damage to crop plants by feeding and transmission of plant viruses. In Pakistan, cotton-vegetable agroecosystems are vulnerable to whitefly-transmitted virus (genus Begomovirus; family Geminiviridae) infection. The identity and distribution of the whitefly B. tabaci mitotypes associated with the cotton crop were studied in 8 districts in the Punjab Province from 2014 to 2016. Phylogenetic analysis of the 3-fragment of the mitochondrial cytochrome oxidase I gene indicated the predominant haplotypes belonged to the Asia II-1 mitotype, with pairwise distances ranging from 0.15 to 3.2%. Pairwise distances showed that B. tabaci haplotype diversity varied by district, with the Khanewal harboring the highest divergence at 1.37%, compared to the lowest at 0.50% in the Dera Ghazi Khan district. The median-joining network analysis showed genetic expansion, or a ‘recovery’ trend, following the declining genetic diversity that occurred during the late 1990s to the early 2000s. The Asia II-1 mitotype group was the predominant whitefly vector species in Punjab Province. The haplotype network provides documentation of continued genetic expansion among the B. tabaci populations in the Punjab, which is consistent with previously reported trends among whiteflies sampled in the same or nearby districts from 2012 to 2014. Genetic expansion varied among districts and could be explained by factors unique to each district, i.e., management practices that influence B. tabaci mitotype composition, whitefly susceptibility to cotton leaf curl disease complex, and cotton genotype

Little is known about the differences between the habitats of domesticated plants and their wild ancestors with respect to the third trophic level. A field study was conducted in the region of origin of domesticated maize to investigate the differences between a maize landrace and the teosinte Zea mays ssp. parviglumis Iltis & Doebley (Poaceae) (the maize ancestor) plants in diversity and density-dependence relationship in the egg parasitoids of corn leafhopper, Dalbulus maidis (DeLong) (Hemiptera: Cicadellidae), within the maize and teosinte habitats. Comparing exposure of both plants within the maize agroecosystem vs. the teosinte wild habitat, eggs of D. maidis were attacked by a community or complex of parasitoids. A higher diversity of adult parasitoids was found in teosinte plants (H′ = 0.73) than in maize landrace plants (H′ = 0.30) within the maize habitat. In addition, within the teosinte habitat a higher diversity of adult parasitoids was seen in the teosinte plants (H′ = 0.88) than in maize landrace plants (H′ = 0.40). Adult egg parasitoids were abundant within maize habitat and included Anagrus virlai Triapitsyn (Hymenoptera: Mymaridae), Paracentrobia sp., and Pseudoligosita sp. (both Hymenoptera: Trichogrammatidae). Within the teosinte habitat, the community of parasitoids included A. virlai, Anagrus incarnatus Haliday (Hymenoptera: Mymaridae), Paracentrobia sp., and Pseudoligosita sp. In the maize habitat, a strong positive density-dependent association was seen between the number of D. maidis eggs and the community of adult parasitoids, and A. virlai, the most abundant and common parasitoid. However, a weak density-dependent association was seen in the teosinte wild habitat. Differences in density-dependent association in D. maidis and the community of egg parasitoids between teosinte wild habitat and maize crop contribute to the understanding of changes in the third trophic level through maize domestication.

Nymphaea mexicana Zuccarini (Nymphaeaceae) (Mexican waterlily) is an emergent floating-leaved aquatic plant from the southeastern USA that is invasive in South Africa. In invaded waterbodies this plant restricts water movement, increases siltation, decreases recreational activities, and can deplete water oxygen levels, which in turn negatively impacts aquatic fauna. Currently there are no chemical, mechanical, or biological control programs in place for N. mexicana in South Africa, but the sustainability of biological control makes this the most desirable option. Field surveys for potential biological control agents were conducted in the native range of N. mexicana in Florida, Louisiana, and Texas from Aug to Oct 2018. Leaves, stems, flowers, and roots of N. mexicana were searched for insect herbivores by hand and using Berlese funnels. Insects were prioritized for use as biological control agents by considering the extent and type of feeding damage, field host range, and incidence (percentage of sites in which each species was found). In total, 15 confirmed species were found feeding on N. mexicana, and some taxa were identified only to family level. Incidence coverage estimator mean, MMRuns, Chao 2 mean, and Chao 2 upper 95% CI species accumulation estimators predicted that between 2 and 5 species were missed during the surveys. Based on field observations, Bagous americanus LeConte (Coleoptera: Curculionidae), and Megamelus toddi Beamer (Hemiptera: Delphacidae) were prioritized. Host specificity trials will be conducted to determine whether these insects may be used as biological control agents of N. mexicana.

Dicyphus hesperus Knight (Hemiptera: Miridae) is an omnivorous natural enemy used to control insect pests in greenhouse structures. The establishment and population development of predators in a banker plant system must be understood prior to their deployment in a pest management program. Banker plants are non-crop plants that are infested with a supplemental food source, which provides a suitable environment for predators to establish their population. The objective of this research was to investigate the effect of mullein (Verbascum thapsus L.; Scrophulariaceae) as banker plants and Ephestia kuehniella Zeller (Lepidoptera: Pyralidae) eggs as supplemental food on the development of D. hesperus in a tomato greenhouse production system. The nymphal development duration did not differ between mullein (22.5 d) and tomato (24.5 d) with E. kuehniella eggs but was significantly longer on mullein (25.8 d) without E. kuehniella eggs, whereas nymphs did not complete their life cycle on tomato without E. kuehniella eggs. Adult longevity and percentage survival to adulthood was 30.4 d and 91.9% on mullein with E. kuehniella eggs, and 26.9 d and 87.5% on tomato with E. kuehniella eggs, but were much reduced on mullein without E. kuehniella eggs (22.44 d and 75%). The population growth of the predator varied in response to host plant and presence of supplemental food source. In greenhouse experiments, the population of D. hesperus showed a greater increase on tomato provided with E. kuehniella eggs as a supplement food source than on mullein with supplemental food. We conclude that there was no benefit in our experiments to using mullein as a banker plant rather than using the commercial crop, tomato, supplemented with E. kuehniella eggs.

Solenopsis invicta Buren (Hymenoptera: Formicidae) is an aggressive invasive species in many parts of the world, including the southeastern USA. The objectives of this study were to document S. invicta occurrence and predation potential of lepidopteran pests in peanut and cotton fields in the Florida Panhandle. The predation potential of S. invicta on Helicoverpa zea (Boddie) (Lepidoptera: Noctuidae) was evaluated in experimental areas of peanut and cotton at the West Florida Research and Education Center, University of Florida/IFAS, Jay, Florida, USA, during 2 crop seasons. Overall, we found a beneficial aspect of this invasive species in the agroecosystems of the Florida Panhandle.

The invasive whitefly species Bemisia tabaci MED (Gennadius) (Hemiptera: Aleyrodidae) has demonstrated the ability to develop higher levels of insecticide resistance than B. tabaci MEAM1, leading MED to displace MEAM1 in some regions when insecticide resistance management is not practiced. Displacement of MEAM1 by MED is influenced also by host plant. MED established recently in the Florida landscape, making it necessary to evaluate the risk that MED will displace MEAM1 on tomato and other economically important crops. The development of MEAM1 and MED was observed on tomato (cv. ‘Florida 91') 30, 45, and 70 d after inoculation separately and in the presence of the other species. MEAM1 were more abundant than MED on plants where both were combined 30, 45, and 70 d after inoculation. MEAM1 reached higher numbers than MED on plants where they were established separately 30 and 70 d after inoculation. At 70 d after inoculation, there were significantly more MED on tomato plants where MEAM1 was not present than on plants infested with both species. Our results indicate that MEAM1 has a competitive advantage over MED on tomato in the absence of insecticide applications. In addition, we tested 13 populations of MEAM1 from commercial vegetable fields and 2 populations of MED from residential hibiscus for tolerance to imidacloprid and thiamethoxam. The 2 MED populations did not demonstrate high levels of tolerance to these insecticides relative to the MEAM1 populations. Our results suggest that the displacement of MEAM1 by MED in Florida tomato fields is unlikely at the present time.

Leidyula floridana (Leidy) (Gastropoda: Veronicellidae) has long been known to be a plant pest in the Caribbean region and southern Florida, though its range has expanded to include northern Florida, other Gulf Coast states, and Mexico. It is nocturnal, and often overlooked as a source of plant damage. Although polyphagous, it does not feed on all plants, and it is desirable to know what bedding plants will likely be damaged by this common herbivorous slug. To identify readily accepted bedding plants, I conducted a series of comparative trials of 7 d duration to assess the acceptance of 30 commonly grown bedding plants relative to French marigold, a plant that is commonly fed upon by slugs and snails. Several commonly grown bedding plants were shown to be very susceptible to feeding injury. In a second set of 7-d trials, I compared 14 plants from among those that were not readily accepted in the first set of trials to determine if they would remain poorly accepted when not provided with favored food. In the second set of trials, the levels of herbivory shown in the first trials were maintained, demonstrating that some bedding plants are not acceptable to L. floridana even when the slugs do not have access to acceptable food. Thus, a list of readily available bedding plants that resist herbivory by this slug has been determined, providing gardeners with slug-resistant choices. The most unacceptable species (damage rating = 1.00) were: lantana (Lantana camara L.; Verbenaceae), tickseed (Coreopsis spp.; Asteraceae), torenia (Torenia fournieri Linden ex E. Fourn.; Linderiaceae), angelonia (Angelonia angustifolia Benth.; Plantaginaceae), and snapdragon (Antirrhinum majus L.; Plantaginaceae). Additional plant species that were not very acceptable (damage rating of between 1.00 and 1.50) were blue daze (Evolvulus glomeratus Choisy; Convolvulaceae), dusty miller (Centaurea cineraria [L.] Jacq. ex Nym.; Asteraceae), viola (Viola hybrid; Violaceae), celosia (Celosia argentea L.; Amaranthaceae), and geranium (Geranium spp.; Geraniaceae). In contrast, plant species that seem to be at considerable risk of damage (damage rating 3 to 5) by L. floridana were: French marigold (Tagetes patula L.; Asteraceae), Madagascar periwinkle (Catharanthus roseus [L.] G. Don; Apocyanaceae), coleus (Plectranthus scutellarioides [L.] R. Br.; Laminaceae), petchoa (Petunia × Calibrachoa; Solanaceae), zinnia (Zinnia elegans Jacq.; Asteraceae), polka dot plant (Hypoestes phyllostachya Baker; Acanthaceae), chrysanthemum (Chrysanthemum morifolium Ramat; Solanaceae), petunia (Petunia spp.; Solanaceae), Stokes' aster (Stokesia laevis [Hill] Greene; Asteraceae), scarlet sage (Salvia splendens Sellow ex Nees; Lamiaceae), butter daisy (Melampodium paludosum Kunth; Asteraceae) and verbena (Verbena spp.; Geraniaceae). A few species were intermediate in susceptibility, namely: impatiens (Impatiens hawkeri W. Bull; Balsamaniaceae), wax begonia (Begonia × Semperflorens × Cultorum; Begoniaceae), sweet potato vine (Ipomoea spp.; Convolvulaceae), firecracker flower (Crossandra infundibuliformis [L.] Nees; Acanthceae), sweet William (Dianthus barbatus L.; Caryophyllaceae), pansy (Viola × Wittrochinana; Violaceae), purslane (Portulaca oleraceae L.; Portulacaceae), and alyssum (Lobularia maritima [L.] Desv.; Brasscaeae).

The fall armyworm, Spodoptera frugiperda (J.E. Smith) (Lepidoptera: Noctuidae), is an invasive insect pest attacking maize in Ghana and sub-Saharan Africa countries. Biological control will need to be an important management strategy, and a first step was to identify potential natural enemies. Sampling was conducted in different localities of the 10 regions of Ghana from May to Nov 2017. A total of 1,062 larvae were collected from 106 maize farms, and the presence of natural enemies was recorded in 18 (17.0%) farms. Among natural enemies recorded, 7 species were parasitoids: Chelonus bifoveolatus Szpligeti, Coccygidium luteum (Brull), Cotesia icipe Fernandez, Meteoridea testacea (Granger), and Bracon sp. (all Hymenoptera: Braconidae), Anatrichus erinaceus Loew (Diptera: Chloropidae), and an undetermined tachinid fly (Diptera: Tachinidae). The parasitism rate was 3.58%. Three predator species were collected: Pheidole megacephala (F.) (Hymenoptera: Formicidae), Haematochares obscuripennis Stål, and Peprius nodulipes (Signoret) (both Heteroptera: Reduviidae). The 2 most abundant parasitoids were C. bifoveolatus and C. luteum with a relative abundance of 29.0% and 23.7%, respectively, and a parasitism rate of 1.04% and 0.85%, respectively. However, C. bifoveolatus was the most dispersed parasitoid, found in 6.6% of the inspected sites within all the agroecological zones of Ghana. This species is a good candidate as a biological control agent for fall armyworm in Africa. The predator that was most abundant (46.0%) and dispersed (3.8% of the farms) was P. megacephala.

The sugarcane aphid, Melanaphis sacchari Zehntner (Hemiptera: Aphididae), is recognized as an important pest of sorghum cultivation. The use of natural products in the form of botanical extracts represents an alternative for its control. In this investigation, we evaluated the insecticidal activity of hexanic, acetonic, and methanolic extracts of leaves, fruits, and roots of Ricinus communis L. (Euphorbiaceae). These were applied in contact bioassays at different concentrations to control apterous adults of M. sacchari. We found that the chemical components of lower polarity contained in the hexane extract of leaves (RcLH) produced the best biological effect, with 96% mortality at 72 h. Thin layer chromatography allowed fractions of this extract to be grouped into 7 categories (F1–F7) based on their chemical content. The F3 category produced 90% mortality at 10,000 ppm at 72 h in contact bioassays. The ¹H and ¹³C nuclear magnetic resonance analysis in addition to the gas chromatography-mass spectrometry of F3 revealed the presence of myristic and stearic acid. Our results showed that the hexanic extracts of R. communis and their fatty acids may be an alternative for the development of new insecticides, constituting a better option in terms of effectiveness and lower toxicity compared with the synthetic products currently on the market used for their control.

Early detection of potential threats relies on solid knowledge of exotic species and potential pathways of introduction. Here we provide a review of potential pest bark and ambrosia beetles recorded from Cuba but not present in the USA. Highlighted are genera which contain species known to have caused significant economic damage. This information is highly relevant to entomologists and practitioners involved in forest and tree industries, as well as biosecurity.

Wasmannia auropunctata (Roger) (Hymenoptera: Formicidae) is among the world's worst invasive species, and there is an increasing need for effective control methods for this species. Existing chemical treatments and baits used in managing other invasive ant species may not be as effective for managing W. auropunctata. Development of effective ant control treatments and baits depends on laboratory experiments to test the potential efficacy of a large number of products and control methods prior to implementation of large-scale field studies. However, anecdotal evidence suggests that laboratory-raised W. auropunctata may respond differently than their wild counterparts to bait types, and if this is the case, laboratory trials may not accurately predict results under field conditions. Here we report on experimental research investigating whether ant colonies raised in laboratories, and those in the field, show different patterns of recruitment to non-toxic baits. Laboratory and wild colony recruitment to non-toxic Hawaii Ant Lab gel bait, pureed tuna, and 50% gelled sucrose solution was measured via multi-choice and no-choice field recruitment studies. Secondly, we discuss experiments testing whether the bait preference of laboratory-raised W. auropuncata varies with their base diet. We tested 4 base diets: (1) lipid rich, (2) protein rich, (3) carbohydrate rich, and (4) a “complete” diet with lipid, protein, and carbohydrates offered as a buffet. Overall, we found that laboratory colonies differed from wild W. auropunctata in their foraging behaviors in no-choice and multi choice experiments, particularly in their levels of recruitment to the Hawaii Ant Lab gel bait. This contrast indicates that experimental trials may give misleading indications of potential outcomes of field trials. Further research is needed on optimal laboratory diets for laboratory-reared ant colonies. However, our results suggest that behavioral differences may be mitigated if colonies are maintained on a nutritionally limited diet while conducting laboratory experiments.

Phorid flies (Diptera: Phoridae) parasitize insects of many orders including leaf-cutting ants, which are pests of several crops. These parasitoids may have a significant impact on ant behavior by altering their foraging rhythm. Seasonal variations in climatic variables, such as temperature and humidity, influence the abundance, activity period, distribution, and reproduction of insects. Therefore, knowledge of parasitoid seasonal patterns is important for biological control success. In this study we evaluate the parasitism of the leaf-cutting ant Atta sexdens L. (Hymenoptera: Formicidae) by Apocephalus attophilus Borgmeier and Eibesfeldtphora tonhascai Brown (both Diptera: Phoridae) across seasons throughout a yr in a Brazilian Cerrado-Atlantic Forest ecotone, and compare their parasitism in a semi-deciduous seasonal forest fragment and urban area. The number of ants parasitized by A. attophilus and E. tonhascai was higher in the winter and spring, respectively, but similar in summer and fall. Apocephalus attophilus parasitism was negatively correlated with temperature but not with relative humidity, whereas ant parasitism by E. tonhascai presented no correlation with either parameter. The number of ants parasitized by A. attophilus and E. tonhascai in the semi-deciduous seasonal forest fragment was higher than in urban areas. Knowledge of biotic and abiotic factors influencing the population dynamics of phorid flies is important for rearing and releasing protocols for these parasitoids.

Sugarcane aphid, Melanaphis sacchari Zehntner (Hemiptera: Aphididae), is now widely established in sorghum, Sorghum bicolor (L.) Moench (Poaceae), production areas of the USA, and is an important economic pest. To calculate economic thresholds, population growth parameters under varied temperature conditions are needed. However, detailed laboratory studies of temperature effects on the biology and population parameters of M. sacchari since the sorghum outbreak in the US have not been performed previously. Therefore, this study evaluated the response of M. sacchari to 6 different constant temperatures (15, 20, 25, 30, 32, and 35 °C) on sorghum tissue. Aphid development, age-specific survivorship, fecundity, and longevity were compared at the mentioned temperatures. At 20 °C, the reproductive period was longest and total fecundity was greatest. Development time of M. sacchari was shortest at 25 and 30 °C. Intrinsic rate of increase was highest at 25 °C (r_m = 0.405 ± 0.030). Net reproductive rate (R₀) was highest at 20 °C, and age-specific survivorship decreased with increasing temperature. At 25 °C, aphid populations doubled in 1.7 d, the shortest among all temperatures tested. Using a modification of the nonlinear Logan model, the lower and upper developmental thresholds of M. sacchari were calculated at 8.6 and 37.8 °C, respectively, with the optimum temperature for development occurring at 28.3 °C. Population parameters, together with high minimum and maximum thermal thresholds, indicate that M. sacchari is an aphid species adapted to higher temperatures.

Field surveys of the parasitic plant Cuscuta lupuliformis (Convolvulaceae) conducted in Poland in 2018 revealed extensive infestations by larvae of the monophagous fly Melanagromyza cuscutae (Diptera: Agromyzidae). Thirty to 60% of dodder populations were infested in sample areas from alluvial forests, scrubs, flood embankments, and wasteland habitats. This is the first report of M. cuscutae from Poland and north of the Carpathians, significantly expanding its range northwards. This fly has potential as a biological control agent of dodders, because of larval feeding resulting in damage, necrosis, and reduced seed production of this parasitic plant.

We found Multilure traps baited with Strepha Trap^® to be a useful method for sampling arboreal ants. A total of 7 ant species (Hymenoptera: Formicidae) were recorded from 8 Multilure traps associated with tree canopies in a Neotropical transition region in northeastern Mexico. The genus Azteca and the species A. schimperi Emery are reported for the first time in the state of Tamaulipas, Mexico. This finding represents the northernmost distribution of these species in the Americas.

The cultivation of hardy pecan, Carya illinoinensis (Wangenh.) K. Koch (Juglandaceae), has increased in Brazil in the current century; however, the knowledge about insect pests is limited. This report deals with the occurrence of Gymnandrosoma aurantianum (Lima) (Lepidoptera: Tortricidae) in pecan trees for the first time in Brazil, discussing symptoms and possible risks.

In Florida, waterhyacinth (Pontederia [Eichhornia] crassipes) (Martius) Solms Laubach (Pontederiaceae) is primarily controlled by herbicides, but overall control is enhanced by insect biological control agents that decrease growth and reproduction and slow regrowth. However, herbicide applications often disrupt the biological control agent populations when applied indiscriminately. Previous studies identified the utility of preserving populations of biological control agents in the vicinity of herbicide treated areas by establishing refuges for the insects. The objectives of this experiment were to quantify the impact of insect refuges, using groups of untreated P. crassipes within treated mats, on the regrowth of the new mat and the ability of biological control agents to persist following an herbicide treatment. Pontederia crassipes mats were grown with and without biological control agents, then treated with 2 concentrations of the herbicide penoxsulam. Plant growth metrics and biological control agent densities were monitored pre- and post-treatment and compared using ANCOVAs and non-parametric Kruskal-Wallis tests. Although the systemic activity of penoxsulam in the water column prevented the establishment of refuges in this study, biological control agent populations persisted following herbicide applications without additional releases and were able to remain at field densities after the decay and loss of P. crassipes. The treatment with no biological control agents and only half-label rate herbicide grew more densely, had greater dry weight biomass, higher relative growth rate, and produced more inflorescences than the plants in treatments with biological control agents. The half-label herbicide and biological control agent treatment performed as well as both treatments with label rate herbicide, and with and without biological control agents, respectively, in lowering P. crassipes density, final dry weight biomass, and relative growth rate. Although the concept of refuge systems at operational field scales requires further study, demonstrating the ability of biological control agents to persist even on sprayed mats is a necessary first step in determining the temporal and spatial factors that might influence the utility of such refuges.

Eggs, nymphs, and adults of Halyomorpha halys were exposed to 15%, 35%, 55%, 75%, or 90% RH provided by glycerol-water solutions. Although egg hatch and nymphal survival occurred at all concentrations, they were highest at 55% to 90% RH. Nymphs exposed at the second instar reached the adult stage only at 55% to 90% RH. Females laid the greatest number of egg clutches at 55% RH. Therefore, we believe that H. halys could survive in Florida at 55% to 90% RH, but would be most prolific at 55%.

Flight mills were used to investigate flight capabilities of Allograpta obliqua (Say) (Diptera: Syriphidae), an important predator of Asian citrus psyllid, Diaphorina citri Kuwayama (Hemiptera: Liviidae), in California. Specifically, distance by which A. obliqua can fly in 24 h, and the effect of sex and feeding treatment (fed or starved) on flight capabilities were investigated. A total of 17 (7 females, 10 males) laboratory-reared flies were flown. There was no significant effect of sex on distances flown. Out of a total of 3,487 flight bouts, 7 consisted of A. obliqua flying 1 to 2 m, and 5 bouts consisted of A. obliqua flying over 5 m. The remaining bouts (99.7%) were less than 1 m and were considered ‘hovering’ because they consisted of extremely short bursts of flight activity (< 10 s). The 5 bouts over 5 m were conducted by 2 fed females, and the mean distance flown and mean flight bout time were 39 ± 13 m and 113 ± 24 s, respectively.

The expansion of the area planted with Eucalyptus species and the trade of its products in the world have been accompanied by accidental introduction of exotic insects. The genus Phoracantha Newman (Coleoptera: Cerambycidae), from Australia and New Guinea, has 40 borer species that use trees and freshly cut logs of the genus Angophora, Corymbia, and Eucalyptus. The objective of this report is to document the occurrence of P. recurva damaging weakened C. citriodora trees in an urban area of the Atlantic rainforest in Viçosa, Minas Gerais State, Brazil. Extensive feeding galleries and the presence of a P. recurva male adult were found in the trunks of weakened trees of C. citriodora logs in an area near the forest nursery of the Universidade Federal de Viçosa. This is the first report of this borer species in this climate zone of the Atlantic rainforest biome of Minas Gerais, Brazil. This suggests that P. recurva has high plasticity to establish in regions with different climatic conditions, being able to survive in most regions of Brazil. The record of P. recurva infesting C. citriodora trees in the Minas Gerais Atlantic rainforest region increases its distribution in Brazil. This knowledge is important in reducing or preventing its damage in Brazil.

Melanaphis sacchari Zehntner (Hemiptera: Aphididae) is an important destructive pest in forage sorghum in Nuevo León, Mexico. This study was conducted to identify predatory and parasitoid insect species associated with this pest in Nuevo León, and their impact on its biocontrol. During the monitoring period, identified insects indicated the coexistence of 8 coccinellid species, 2 syrphid species, and 1 chrysopid species. In addition, 2 hymenopteran species were identified. After the insecticide applications, sugarcane aphid population was reduced by about 20.6% (about 14 nymphs per cm²); when the sampling ended, population was reduced by about 70.6% (about 5 nymphs per cm²), thus indicating predator and parasitoid biocontrol. Collected data allowed us to conclude that the biological controllers were responsible for the principal pest population reduction. Overall, results showed that yellow sugarcane aphid predatory and parasitoid species may play an important role in the pest management in sorghum crops in Nuevo León, Mexico.