白星花金龟对寄主植物挥发物的电生理反应

[目的]白星花金龟Protaetia brevitarsis是我国经济上重要的农业害虫.本研究拟鉴定苹果、葡萄和玉米3种果实在两种状态(健康与受白星花金龟成虫为害)下的挥发物中能引起白星花金龟雌成虫触角电生理反应的挥发物成分.[方法]采用动态顶空吸附法收集苹果、葡萄和玉米3种果实的挥发物,用气相色谱-触角电位联用技术(...     

Distribution and adult activity of Popillia quadriguttata (Coleoptera: Scarabaeidae) on golf courses in Korea

Japanese beetle traps baited with the Popillia japonica Newman (Coleoptera: Scarabaeidae) pheromone lure and a eugenol feeding attractant were placed at five golf courses in Korea to determine how well they work for detecting activity of a closely related species, Popillia quadriguttata (F.) (Coleoptera: Scarabaeidae), a turf pest in Korea. The traps also were used to determine the time of day and time of year that P. quadriguttata is most active. Nineteen scarab species of 13 genera were attracted to the Japanese beetle traps with P. quadriguttata clearly being the most abundant (383 beetles per trap), followed by Adoretus tenuimaculatus Waterhouse (10 per trap), Popilliaflavosellata Fairmaire (seven per trap), Exomala orientalis Waterhouse (four per trap), and Maladera japonica (two per trap). Other scarab species were trapped at a rate of <1.0 per trap. Popillia quadriguttata adults were active over a 5-wk period in late June and early July. At Yongwon Golf Club in 2002, peak adult activity was during the last week of June in visual counts and approximately 1 wk later in the Japanese beetle traps. In Korea, P. quadriguttata adults are most active between 12:00 p.m. and 4:00 p.m. This information should be helpful to golf course superintendents in Korea and to entomologists interested in finding natural enemies of P. quadriguttata to evaluate as potential biocontrol organisms for the very closely related species, the Japanese beetle.     

Ultrastructure of pheromone-detecting sensillum placodeum of the Japanese beetle, Popillia japonica Newmann (Coleoptera: Scarabaeidae)

The pheromone-detecting sensilla placodea are significantly more numerous than other sensory structures in the antennae of the Japanese beetle, Popillia japonica (Coleoptera: Scarabaeidae). Their abundance in males is nearly twice of that in females, showing a clear sexual dimorphism. Externally, they have a tortoise shell-like round cuticular plate containing a few polygonal plates separated by narrow ridges. Internally, they house two long dendrites that branch and terminate near fine cuticular pores. They have a system of two bipolar neurons accompanied by three enveloping cells, resembling sensilla trichodea in moths. The conspicuous difference with the latter is that the sensillum-lymph cavity near the outer cuticle is funnel-shaped, into which the tormogen cell projects numerous microvilli whose tips approach the terminal branches of the dendrites.     

Japanese beetle lures used alone or combined with structurally related chemicals to trap NE China scarabs (Coleoptera: Scarabaeidae)

Scarab beetles are agriculturally important worldwide, and as adults or larvae they may cause damage to the leaves, flowers, fruit, and roots of crops. Previous international studies showed that Japanese beetle (Popillia japonica, Newman) lures, and structurally related chemicals, can attract numerous scarabs. Based on those studies, season-long trials in grape, cabbage, corn and soybean fields were conducted in 2012–2013 in NE China. Tests determined the attractiveness of the Japanese beetle floral lure (phenethyl propionate:eugenol:geraniol, 3:7:3) and sex attractant (Japonilure), alone, combined, or in a mixture with either (Z)-3-hexen-1-ol, anethole = 1-methoxy-4-propenyl benzene or benzyl alcohol, to local Coleoptera. Furthermore, control efficacies based on leaf, ear, and silk damage, as well as reductions of adults on plants, and overwintering larvae, were also determined. Eleven scarab species, and four non-scarab species, were captured. The addition of other chemicals increased the attractiveness of the two Japanese beetle lures to scarabs such as Potosia brevitarsis (Lewis), Oxycetonia jecunda Faldermann, Holotrichia diomphalia Bates et al., Popillia quadriguttata (Fabricius), Maladera verticalis (Fairmaire), and Metabolus impressifrons Fairmaire, and the chrysomelid beetle Chrysomela populi L. The floral lure, and floral lure plus Japonilure baited traps resulted in > 80% overwintering larvae and adult reductions in corn and cabbage fields, whereas the Japonilure traps gave similar results in the soybean fields. This indicates that the commercial Japanese beetle lure combination can be recommended for use by the Chinese farmers in the corn or soybean fields, and that the related chemicals can be used to increase the attractiveness of the Japanese beetle lures.     

Male mate searching behavior in the black chafer Holotrichia loochooana loochooana (Sawada) (Coleoptera: Scarabaeidae): response to pheromone lures of various colors and intensities

In order to understand the visual orientation mechanisms of the male black chafer Holotrichia loochooana loochooana to females, we examined male behavioral response to colored objects (lures) when female sex pheromone was present. In the field, males landed more frequently on darker lures than on lighter ones of the same color. Among lures of different colors but with the same brightness, males preferred landing on black, blue, or red ones to green or grey ones. The reflectance intensities of preferred lures were weaker than those of green and grey in the range of 540–580 nm. This range is considered to affect choice by males. When females perch on the leaf edges of the food plant to adopt a calling posture, the dominant background color is that of the leaves (i.e., green). This means that the landing target forms a silhouette (dark spot) which is prominent against a background of green leaves, providing maximum visual acuity for mating.     

Potential resistance of crape myrtle cultivars to flea beetle (Coleoptera: Chrysomelidae) and Japanese beetle (Coleoptera: Scarabaeidae) damage

Field and laboratory studies were conducted to identify potential resistance among crape myrtles, Lagerstroemia spp., to Japanese beetle, Popillia japonica Newman and to flea beetles, Altica spp. Damage ratings revealed variation among cultivars in susceptibility to beetle feeding. Cultivars with Lagerstroemia fauriei Koehne in their parentage exhibited the least amount of damage in choice and no-choice experiments, with few exceptions. The data indicate that both beetle species cause more feeding damage on certain cultivars of Lagerstroemia indica L., such as 'Country Red', 'Twilight', and 'Carolina Beauty' than interspecific cultivars with L. fauriei in their parentage, such as 'Natchez', 'Tonto', and 'Muskogee'. When comparing the effect of parentage on all of the major pests of crape myrtle, L. faurei confers resistance to all pests except crape myrtle aphid. No correlation was found between leaf toughness, leaf color, and leaf nutrients in estimating flea beetle cultivar preference. With this information, growers can more effectively target scouting measures to the most susceptible cultivars. and breeders can select plants that will require the fewest chemical inputs.     

Impact of Japanese beetle (Coleoptera: Scarabaeidae) feeding on seashore paspalum

Ten cultivars of seashore paspalum, Paspalum vaginatum Swartz, were compared for their response to Japanese beetle, Popillia japonica Newman, larval root feeding. Cultivars of Bermuda grass, Cynodon sp., and zoysiagrass, Zoysia sp., also were included for comparison. Turf grown in pots in the greenhouse was infested with second and third instars in this 2-yr study. Grub survival and weight gain, foliar growth, and root loss were compared among turfgrass species and cultivars. Few species-related differences were identified. Differences in grub tolerance were, however, observed to be a function of turfgrass cultivar. Some turf types demonstrating tolerance to grub feeding had rapid root growth and high root mass in control pots, but this was not consistent for all cultivars showing enhanced ability to maintain foliar growth despite grub feeding. The paspalum cultivars that seemed most tolerant of grub feeding were '561-79', 'Sea Isle 2000', 'Durban', 'HI-10', 'Kim-1', 'Sea Dwarf', and 'Sea Spray'.     

白星花金龟(Protaetia brevitarsis)幼虫抗菌物质的分离纯化

以药用昆虫白星花金龟(Protaetia brevitarsis)幼虫为研究对象,通过Sephadex G-50、RP-HPLC等技术分离纯化天然抗菌活性物质.经初步鉴定,该系列抗菌活性物质对枯草芽孢杆菌(Bacillus subttilis)表现出较强的抑菌活性.用MALDI-TOF MS对样品进行分析,检测到相对分子质量分别为2254.045 9、2622.4438的两种抗菌活性物质.推测这些抗菌活性物质在白星花金龟幼虫抵御微生物的侵袭中起到重要作用.     

Dispersal of Steinernema glaseri (Nematoda: Steinernematidae) in adult Japanese beetles, Popillia japonica (Coleoptera: Scarabaeidae)

Japanese beetle adults, Popillia japonica, can become infected with and disperse the entomopathogenic nematode, Steinernema glaseri, under laboratory and field conditions. After a 24-h exposure to 10 000 infective juveniles/20 adult beetles, 45% of the beetles died within 4 days post-treatment, but only 59% of these were infected with the nematode. Corresponding control mortality was 6.5%. An average of 238 infective juveniles were produced/beetle. Beetles exposed to 4000 and 10 000 infectives/10 adults carried with them an average of 17 and 59 infectives/adult on external body surfaces respectively. When beetles that had been exposed to 4000 infectives/20 adults were transferred to, and held in, cages containing soil for 2 weeks, up to 89% of the adults died, as did 74% of the P. japonica larvae that were subsequently placed in the cages. When adults that had been exposed to 50 000 infectives/250 beetles in moist sand for 16 h were released into screened cages in the field at soil temperatures of over 25 C, the soil beneath 83% of the cages tested positive for the nematode, using Galleria mellonella larvae as bait, 2 weeks after releasing the beetles. No nematodes were detected in control plots. The potential of infected adult P. japonica for dispersing S. glaseri by flight was investigated by exposing adults to 50 000 infectives/250 beetles, marking and releasing them in the field and recapturing them in lure-baited Japanese beetle traps. Less than 1% of the treated beetles were recaptured, but 33% of these had one or more nematodes in their hemocoels. Accordingly, this approach does not appear to be feasible for large-scale augmentation and dispersal of the nematode using currently developed methods of infection. If improvements in mass-inoculation methods can be made that enable a rapid high percentage of infection while still permitting flight, this concept could be employed to establish new foci of infection or for the introduction of other species of nematodes.     

Dose response of coconut rhinoceros beetle (Coleoptera: Scarabaeidae) to 92 kV x-ray irradiation

To evaluate the potential suitability of x-ray irradiation as a physical control method for invasive Coconut Rhinoceros Beetle (CRB) (Oryctes rhinoceros Linnaeus 1758; Coleoptera: Scarabaeidae), either through sterile insect technique (SIT) or through direct irradiation of naturally infested materials in the field, we recorded longevity of eggs, larval and adult life stages of CRB irradiated with different doses of x-rays emitted from a tube energized at 92 kV. Eggs and larvae were highly susceptible to radiation at all tested doses (down to about 2–5 Gy), though adults required larger doses (at least 50 Gy) to render them incapable of reproducing. At exposures near 50 Gy sterilized adults nevertheless were observed to survive for more than a month, suggesting SIT may be a viable control approach for this beetle. Similarly, these results may facilitate the discovery of hidden breeding sites in the wild by tagging and releasing sterilized adults. While larvae were highly susceptible to x-ray irradiation, irradiation would probably not be an effective tool for field control due to rapid attenuation of radiation energy (exponential decay coefficients ranging from about 0.3–0.6 cm⁻¹) in the organic nesting materials we tested, and the tendency for CRB adults to burrow and oviposit deep in mulch (1 m or more).     

Bark-carving behavior of the Japanese horned beetle Trypoxylus dichotomus septentrionalis (Coleoptera: Scarabaeidae)

The Japanese horned beetle, Trypoxylus dichotomus septentrionalis, usually aggregates at the wounds caused by boring insects on Quercus oak trees to feed on exuding sap. Here, a unique behavior of the beetle, which enables it to independently obtain sap without any activities of other insects, is reported. Beetles carved intact bark of Fraxinus griffithii, where no sap was exuding, using clypeus. As a result of carving behavior, bark was stripped, and sap exuded from these scars temporarily, which beetles immediately began to lick. A digital video image relating to the article is available at ().     

Developmental stages and gut microenvironments influence gut microbiota dynamics in the invasive beetle Popillia japonica Newman (Coleoptera: Scarabaeidae)

Popillia japonica Newman (Coleoptera: Scarabaeidae) is a highly polyphagous invasive beetle originating from Japan. This insect is highly resilient and able to rapidly adapt to new vegetation. Insect-associated microorganisms can play important roles in insect physiology, helping their hosts to adapt to changing conditions and potentially contributing to an insect's invasive potential. Such symbiotic bacteria can be part of a core microbiota that is stably transmitted throughout the host's life cycle or selectively recruited from the environment at each developmental stage. The aim of this study was to investigate the origin, stability and turnover of the bacterial communities associated with an invasive population of P. japonica from Italy. Our results demonstrate that soil microbes represent an important source of gut bacteria for P. japonica larvae, but as the insect develops, its gut microbiota richness and diversity decreased substantially, paralleled by changes in community composition. Notably, only 16.75% of the soil bacteria present in larvae are maintained until the adult stage. We further identified the micro-environments of different gut sections as an important factor shaping microbiota composition in this species, likely due to differences in pH, oxygen availability and redox potential. In addition, P. japonica also harboured a stable bacterial community across all developmental stages, consisting of taxa well known for the degradation of plant material, namely the families Ruminococcacae, Christensenellaceae and Lachnospiraceae. Interestingly, the family Christensenallaceae had so far been observed exclusively in humans. However, the Christensenellaceae operational taxonomic units found in P. japonica belong to different taxonomic clades within this family.     

Location and ultrastructure of sex pheromone glands in female Callosobruchus maculatus (Fabricius) (Coleoptera : Bruchidae)

The ultrastructure of the female sex pheromone glands in Callosobruchus maculatus (Coleoptera : Bruchidae) were localized using a masking technique, combined with eiectro-antennography and by a comparison of the glandular cells of sexually active (flightless) females and non-sexually active (flight-form) females. Each unicellular gland is an invagination of the integumental membrane capped by a single secretory cell. These glands are situated on the fine intersegmental membrane, which joins the pygidium to the ovipositor. The secretory cells of the glands of active females are characterized by well-developed microvilli, with many elongated mitochondria among the latter. The high metabolic activity of these cells is revealed by the presence of heterogeneous secretion vesicles, some of which contain abundant crystallized material. Deep basal invaginations indicate the uptake of substances from the haemolymph. The receptor canal is a network of fine cuticular filaments which have the same structure regardless of the female's sexual status. Cells from the glands of non-sexually active females are underdeveloped and show no invaginations of the basal membrane and very few microvilli. The localization of these glands was made possible by the use of SEM, TEM and EAG as well as by masking the suspected zones and by comparing females in different physiological states: flightless females, which were sexually active and producing pheromones; and flight-form females, non-sexually active and producing no sex pheromones. Only by adopting such a stringent method was it possible to confirm the function of the glands whose ultrastructure was studied.     

Survey of pathogens and parasitoids of Popillia japonica (Coleoptera: Scarabaeidae) in northwest Arkansas

The impact of pathogens and parasitoids on the recently established population of Popillia japonica Newman in northwest Arkansas has been unknown. In this study, we quantified the prevalence of natural enemies: Stictospora villani Hays, Ovavesicula popilliae Andreadis and Hanula, Paenibacillus spp. (Dingman), nematodes and parasitic Diptera and Hymenoptera in third instar and adult populations in 2010 and 2011. S. villani was found in 38.4% and 35.5% of larvae in 2010 and 2011, respectively. S. villani was not found in adult beetles. Paenibacillus bacteria were not found in either larvae or adults in either year. In 2010, the microsporidian O. popilliae was not found in larvae but was present in 0.2% of adults. In 2011, 2.6% of larvae were infected with O. popilliae, but the microsporidian was not found in adults. A previously unknown Adelina sp. was found infecting 0.4% of adult beetles in 2010 and 1.3% of larvae in 2011. Nematode infections were found in 1.8% of larvae and 0.1% of adults in 2010 and not found in either life stage in 2011. No parasitic Hymenoptera or Diptera were found in either year. Apparently, pathogens and parasitoids currently provide little control of the Japanese beetle population within northwest Arkansas.     

Effect of different diets on larval growth of Protaetia brevitarsis seulensis (Kolbe) (Coleoptera: Cetoniidae)

The white-spotted flower chafer, Protaetia brevitarsis seulensis (Kolbe), is used as an important source of medicinal properties, such as anti-cancer activity and prevention of liver-related diseases, in Korea. To use this insect species without endangering wild populations, a mass rearing technique is needed. The present study was carried out to determine whether different diets can affect the larval growth of P. brevitarsis seulensis . Six different diets were investigated in the experiment, and the results showed that 20% rice straw with 80% oakwood sawdust was the best diet for larval growth of this beetle.     

Comparisons of standard and extended-life boll weevil (Coleoptera: Curculionidae) pheromone lures

The Southeastern Boll Weevil Eradication Program has proposed reducing maintenance program costs in eradicated zones by using an extended-life "superlure" in traps to detect populations of the boll weevil, Anthonomus grandis grandis Boheman. However, superlure effectiveness has not been extensively evaluated. We compared the superlure (30 mg of eugenol plus 25 mg of grandlure) to a standard lure (10 mg of grandlure) based on captures of weevils and changes in lure pheromone content. Lure treatments (standard and superlure, replaced biweekly or not replaced) were compared in 4-mo-long trapping periods. Captures of weevils did not generally reflect differences among lure treatments indicated by assays of lure contents. During the first 2 wk of exposure, amounts of pheromone released by the superlure were generally comparable with those of the standard lure, but pheromone composition was more stable. During the second 2 wk of exposure, the superlure usually released more pheromone than similarly aged standard lures, but less than half as much as the standard lure replaced biweekly. Based on numbers of captured weevils during the last 2 wk of an extended trapping period, the superlure performed similarly to the standard lure replaced biweekly. However, corresponding pheromone releases by the superlure were less than those by the standard lure replaced biweekly. This inconsistency suggests that numbers of captured weevils alone may be inadequate for evaluation of pheromone formulations. Our results suggest that better understanding of the consequences of reduced pheromone release during an extended trapping period is needed before adoption of the superlure can be recommended.     

An Attractant Trap for Autodissemination of Entomopathogenic Fungi into Populations of the Japanese Beetle Popillia japonica (Coleoptera: Scarabaeidae)

Autodissemination may be effective against the Japanese beetle, Popillia japonica Newman, in situations where habitats of its larvae are inaccessible. Trapping systems with attractants for both male and female Japanese beetles are commercially available. We fabricated an inoculation chamber which fits between the top of a standard Trece Catch CanTM Japanese beetle Trap and its holding canister. Beetles which are attracted to the trap fall through a hole in the inoculation chamber and land on a mesh screen. A partial funnel and canister attachment from a metal Ellisco Japanese Beetle Trap was secured beneath a hole in the floor at the opposite end of the chamber. A 10-cm section in the middle of the box, between the entrance hole in the roof and the exit hole in the floor, allows space for a dish containing the inoculum to be placed into the chamber through a door in the side of the unit. The trap has been tested with Metarhizium anisopliae (Metschnikoff) Sorokin as the pathogen. Beetles emerging from the device in the field were captured and returned to the laboratory where the presence of conidia and mortality to adult beetles from the fungus were confirmed.