Factors Affecting Adult Captures of the Cotton Bollworm, Helicoverpa armigera (Hübner) (Lepidoptera: Noctuidae) in Pheromone-Baited Traps

The effects of funnel-trap color, trap height and pheromone formulation on the adult captures of the cotton bollworm, Helicoverpa armigera (Hübner) (Lepidoptera: Noctuidae) were evaluated in traps that were suspended in cotton fields in central Greece. Briefly, in a first trial, the efficacy of funnel traps of three different colors, i.e., green, striped (with black and white stripes) and white, was comparatively evaluated, whereas in a second trial green funnel traps were placed at three heights, i.e., 30, 60 and 90 cm from the ground. Finally, in a third trial we tested the efficiency of green funnel traps with three commercially available pheromone lures. Considering the overall captures, trap color and pheromone formulation affected male captures, whereas trap height had no influence. Captures notably increased in all traps from late August to mid-September. In total, the white funnel trap captured more moths than the green or striped funnel traps. Placement of the traps at different heights did not significantly affect captures, but seasonal differences were observed at individual dates during the trapping period. Barrettine’s pheromone lure provided significantly more captures than the other two (Russell, Trécé) in some of the trap-check dates. The results can be further utilized in the monitoring protocols of H. armigera in cotton fields.

The Diversity of Fruit Fly (Diptera: Tephritidae) on Combination of Attractant and Different Trap Height in Cucumber Field (Cucumis sativus L.)

The main pest in the Cucurbitaceae family is the fruit fly. The common effort to control fruit flies is using a trap with methyl eugenol (ME) and cue lure (CUE) as an insect attractant. The trap height installation is also affecting the fruit fly population. The fruit fly population in the field has an important effect on the damage intensity in the commodity. This research objective was to study the distribution and diversity of fruit fly on the cucumber field with trap height installation and attractant combination. The used research method was Factorial Group Randomized Design (RAKF). The first factor was attractant combination of Metil Eugenol (ME) and Cue Lure (CUE) consisted of 6 treatment levels were K1 : 5 mL ME, K2: 5 mL ME + 1 mL CUE, K3: 5 mL ME + 3 mL CUE, K4: 5 mL ME + 5 mL CUE, K5: 5 mL ME + 7 mL CUE and K6 : 5 mL CUE. While the second factor was the high tramp installation consisted of 3 treatment levels were T1: 50 cm, T2: 100 cm, and T3: 150 cm. The treatment consisted of 3 replication on three different cucumber fields. The result showed discovered fruit fly species were eight species, B. dorsalis (Hendel), B. carambolae Drew & Hancock, B. occipitalis (Bezzi), Z. caudata (Fabricius), B. umbrosa (Fabricius), B. neocognata Drew & Hancock, Z. cucurbitae (Fabricius) and B. albistrigata (de meijere). The dominant fruit fly in each treatment in fruit fly fields was B. dorsalis (Hendel). The best treatment in trapping fruit fly was K1 (5 mL ME) with trap height installation T1 (50 cm). The diversity and species richness of fruit fly in the cucumber field was considered low and uneven.

Australian mosquito assemblages vary between ground and sub-canopy habitats

Background The surveillance and control of mosquito-borne diseases is dependent upon understanding the bionomics and distribution of the vectors. Most studies of mosquito assemblages describe species abundance, richness and composition close to the ground defined often by only one sampling method. In this study, we assessed Australian mosquito species near the ground and in the sub-canopy using two traps baited with a variety of lures. Methods Mosquitoes were sampled using a 4 × 4 Latin square design at the Cattana Wetlands, Australia from February to April 2020, using passive box traps with octenol and carbon dioxide and three variations of a sticky net trap (unbaited, and baited with octenol or octenol and carbon dioxide). The traps were deployed at two different heights: ground level (≤ 1 m above the ground) and sub-canopy level (6 m above the ground). Results In total, 27 mosquito species were identified across the ground and sub-canopy levels from the different traps. The abundance of mosquitoes at the ground level was twofold greater than at the sub-canopy level. While the species richness at ground and sub-canopy levels was not significantly different, species abundance varied by the collection height. Conclusions The composition of mosquito population assemblages was correlated with the trap types and heights at which they were deployed. Coquillettidia species, which prefer feeding on birds, were mainly found in the sub-canopy whereas Anopheles farauti, Aedes vigilax and Mansonia uniformis, which have a preference for feeding on large mammals, were predominantly found near the ground. In addition to trap height, environmental factors and mosquito bionomic characteristics (e.g. larval habitat, resting behaviour and host blood preferences) may explain the vertical distribution of mosquitoes. This information is useful to better understand how vectors may acquire and transmit pathogens to hosts living at different heights. Graphical abstract

Rapid Assessment of Cerambycid Beetle Biodiversity in a Tropical Rainforest in Yunnan Province, China, Using a Multicomponent Pheromone Lure

The Cerambycidae comprise a large and ecologically important family of wood-boring beetles. The purpose of this study was to examine the effectiveness of a generic lure as a potential monitoring tool. Working in a subtropical forest in southwest China, we set traps baited with generic lures at ground level (1 m) and canopy height (~18 m) across 22 randomly located forest plots (12 regenerating forest, 10 mature forest). Three stations were established per plot and each plot was trapped for 7 days in May–June 2013. In total, 4541 beetles of 71 species were caught, including 26 species with 10 or more individuals. We used Hierarchical Modeling of Species Communities (HMSC) to analyze the data and produced informative models for 18 species, showing that trap height, slope, elevation, and leaf-area index were important determinants of cerambycid distribution. Our results demonstrate the potential for using generic lures to detect and monitor cerambycid populations, both for regulatory purposes and for the study of cerambycid beetle ecology. Further research should focus on refining lure blends, and on repeated sampling to determine temporal and spatial dynamics of cerambycid communities.

Population dynamics of Fall Army Worm [(Spodoptera frugiperda) J.E. Smith] (Lepidoptera: Nuctuidae) in maize-cassava intercrop using pheromone traps in Niger Delta Region

Background This study was conducted to generate baseline information on population dynamics of Fall Army Worm (FAW) in cassava-maize intercrop for management technique. Maize (Zea mays) is Africa’s most staple food crop with pest complex as major constraints to its production. The study was carried out at the Abuja Campus of the University of Port Harcourt, Faculty of Agriculture Teaching and Research Farm. A plot size of 3298 m2 was cleared and ploughed; afterward, thirty six (36) ridges were made for the planting. Three varieties of maize grains (a hybrid Oba Super 98, white and yellow locals) were used for the study. Two cropping patterns (Sole maize and Cassava-Maize.-Intercrop) as main factor with a total of 18 sole and 18 intercrop plots and pheromone trap heights (at 1 m and 1.5 m) as sub-factor were used. The traps were mounted 18 days after planting and insect collection commenced at dawn the following day. FAW data in each trap were collected daily between 06.00 and 07.00 h. Maize cobs, fresh and dry weights, numbers of FAW exit holes, tunnels and tunnel lengths were recorded for both cropping patterns in each maize variety. Data were subjected to two-way analysis of variance. Results The results show higher mean value of FAW count in pheromone trap height placed at 1.5 m, and Oba super 98 maize variety intercropped with cassava had higher FAW count. There were significantly higher (P < 0.05) FAW exit holes in maize with pheromone trap height placed at 1.5 m, and maize-cassava intercrops had higher mean values of FAW exit holes. Number of tunnels and tunnel lengths (cm) due to FAW infestation were higher in maize varieties where pheromone traps were placed at 1.5 m. Conclusion Intercropping maize with cassava may suggest increase in FAW bionomics and the presence of abundant host which might increase a spike in its peak period of infestation. The presence of cassava in maize-cassava cropping pattern encourages feeding and/or oviposition of FAW on maize plant; therefore, an alternative cropping pattern should be encouraged in the region.

Maximizing Bark and Ambrosia Beetle (Coleoptera: Curculionidae) Catches in Trapping Surveys for Longhorn and Jewel Beetles

Bark and ambrosia beetles are commonly moved among continents within timber and fresh wood-packaging materials. Routine visual inspections of imported commodities are often complemented with baited traps set up in natural areas surrounding entry points. Given that these activities can be expensive, trapping protocols that attract multiple species simultaneously are needed. Here we investigated whether trapping protocols commonly used to detect longhorn beetles (Coleoptera: Cerambycidae) and jewel beetles (Coleoptera: Buprestidae) can be exploited also for detecting bark and ambrosia beetles. In factorial experiments conducted in 2016 both in Italy (seminatural and reforested forests) and Canada (mixed forest) we tested the effect of trap color (green vs purple), trap height (understory vs canopy), and attractive blend (hardwood-blend developed for broadleaf-associated wood-boring beetles vs ethanol in Italy; hardwood-blend vs softwood-blend developed for conifer-associated wood-boring beetles, in Canada) separately on bark beetles and ambrosia beetles, as well as on individual bark and ambrosia beetle species. Trap color affected catch of ambrosia beetles more so than bark beetles, with purple traps generally more attractive than green traps. Trap height affected both beetle groups, with understory traps generally performing better than canopy traps. Hardwood-blend and ethanol performed almost equally in attracting ambrosia beetles in Italy, whereas hardwood-blend and softwood-blend were more attractive to broadleaf-associated species and conifer-associated species, respectively, in Canada. In general, we showed that trapping variables suitable for generic surveillance of longhorn and jewel beetles may also be exploited for survey of bark and ambrosia beetles, but trapping protocols must be adjusted depending on the forest type.

Population Fluctuation, Influence of Abiotic Factors and the Height of Traps on the Abundance and Richness of Calliphoridae and Mesembrinellidae

Calliphoridae and Mesembrinellidae are relevant to environmental conservation, public health, and forensic entomology. Researches regarding the flight behavior and the influence of abiotic factors on these insects may assist the application of entomology sciences. This study aimed to analyze the population fluctuation of Calliphoridae and Mesembrinellidae, verifying the influence of environmental factors, trap height, and the anthropic effect in the Itaipu–Piratininga lagoon complex, Niterói (RJ). The collections were carried out monthly from September 2015 to August 2016, with fish bait (sardines) exposed for 48 h, totaling six traps, installed in three physiognomies (mangrove, ombrophilous forest, and restinga) at 1.5 and 2.5 m from the ground. Nine thousand seven hundred seventy-three individuals were captured, comprising two families, five genera and 11 species. Chrysomya megacephala (Fabricius, 1794) (Diptera: Calliphoridae) was the predominant species and Mesembrinella bellardiana (Aldrich, 1922) (Diptera: Mesembrinellidae) the least representative, indicating the low preservation level of this ecosystem. There was a weak, positive correlation between abundance of Chloroprocta idioidea (Robineau Desvoidy, 1830) (Diptera: Calliphoridae), Ch. megacephala, Chrysomya putoria (Wiedemann, 1818) (Diptera: Calliphoridae), and Lucilia cuprina (Wiedemann, 1830) (Diptera: Calliphoridae) with the temperature, as well as between the abundance of C. idioidea and Chrysomya albiceps (Wiedemann, 1819) (Diptera: Calliphoridae) with precipitation; however, there was no correlation between abundance and relative humidity. No significant influence of the trap height was observed. We stated a high influence of anthropic effects on the restinga and mangrove physiognomies, while the forest physiognomy still retains its preserved characteristics, with the dominance of forestall species.