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David W Held - One of the best experts on this subject based on the ideXlab platform.
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geranium intoxication induces detoxification enzymes in the japanese beetle Popillia japonica newman
Pesticide Biochemistry and Physiology, 2017Co-Authors: Adekunle W Adesanya, David W HeldAbstract:Abstract Popillia japonica is a generalist herbivore that feeds on > 300 host plant species in at least 72 plant families. It is unknown why P. japonica , despite possessing active detoxification enzymes in its gut, is paralyzed when feeding on the petals of one of its preferred host plant, Pelargonium × hortorum , or on artificial diet containing quisqualic acid (QA), the active compound in zonal geranium. We hypothesized that Pelargonium × hortorum or QA do not induce activity of the cytochrome P450, glutathione S transferase (GST), and carboxylesterase (CoE) detoxification enzymes in P. japonica . In this study, P. japonica were fed petals of zonal geranium or agar plugs containing QA, or rose petals, another preferred but non-toxic host. Midgut enzyme activities of P450, GST, and CoE were then assayed after 6, 12, or 24 h of feeding. In most cases, P450, GST, and CoE activities were significantly induced in P. japonica midguts by geranium petals and QA, though the induction was slower than with rose petals. Induced enzyme activity reached a peak at 24 h after consumption, which coincides with the period of highest recovery from geranium and QA paralysis. This study shows that toxic geranium and QA induce detoxification enzyme activity, but the induced enzymes do not effectively protect P. japonica from paralysis by QA. Further investigation is required through in vitro studies to know if the enzymes induced by geranium are capable of metabolizing QA. This study highlights a rare physiological mismatch between the detoxification tool kit of a generalist and its preferred host.
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absence of food aversion learning by a polyphagous scarab Popillia japonica following intoxication by geranium pelargonium hortorum
Entomologia Experimentalis Et Applicata, 1999Co-Authors: Daniel A Potter, David W HeldAbstract:It is commonly held that food-aversion learning should be more prevalent in polyphagous herbivores than in specialists. We tested the ability of Popillia japonica, a polyphagous scarab, to learn avoidance of a palatable but illness-inducing plant. Beetles that feed on flowers of geranium, Pelargonium × hortorum, became paralyzed, although most recovered within 24 h. In choice tests, naive beetles strongly preferred geranium petals over leaves of linden, Tilia cordata, a highly suitable host. Experienced beetles maintained this preference although it resulted in repeated bouts of paralysis. Fecundity was >10 times higher for beetles fed linden foliage for 2 wk than for those fed only geranium. Nevertheless, when a surplus of both foods was provided, the beetles fed mainly on geranium, resulting in greatly reduced fecundity. These results contradict the view that generalists should show propensity for food-aversion learning. Indeed, in this case, P. japonica continued to prefer the toxic plant, compromising its fitness.
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Absence of food-aversion learning by a polyphagous scarab, Popillia japonica, following intoxication by geranium, Pelargonium × hortorum
Entomologia Experimentalis Et Applicata, 1999Co-Authors: Daniel A Potter, David W HeldAbstract:It is commonly held that food-aversion learning should be more prevalent in polyphagous herbivores than in specialists. We tested the ability of Popillia japonica, a polyphagous scarab, to learn avoidance of a palatable but illness-inducing plant. Beetles that feed on flowers of geranium, Pelargonium × hortorum, became paralyzed, although most recovered within 24 h. In choice tests, naive beetles strongly preferred geranium petals over leaves of linden, Tilia cordata, a highly suitable host. Experienced beetles maintained this preference although it resulted in repeated bouts of paralysis. Fecundity was >10 times higher for beetles fed linden foliage for 2 wk than for those fed only geranium. Nevertheless, when a surplus of both foods was provided, the beetles fed mainly on geranium, resulting in greatly reduced fecundity. These results contradict the view that generalists should show propensity for food-aversion learning. Indeed, in this case, P. japonica continued to prefer the toxic plant, compromising its fitness.
Randy Gaugler - One of the best experts on this subject based on the ideXlab platform.
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aggressive and evasive behaviors in Popillia japonica coleoptera scarabaeidae larvae defenses against entomopathogenic nematode attack
Journal of Invertebrate Pathology, 1994Co-Authors: Randy Gaugler, Yi Wang, James F CampbellAbstract:Larvae of the Japanese beetle, Popillia japonica , respond to attack by infective juveniles of the entomopathogenic nematode Heterorhabditis bacteriophora with aggressive and evasive behaviors. Brushing with the legs and rubbing with the abrasive raster were key aggressive behaviors associated with nematode attack in petri dish assays. Remarkably, contact with even a single live nematode triggered behavioral countermeasures directed at eliminating the attacker. Unrestrained P. japonica free to display aggressive behaviors removed more than 60% of attacking nematodes from their cuticle and experienced significantly less parasitism than larvae restrained from displaying defensive behaviors (13% or less of the nematodes removed). Unrestrained larvae were also capable of killing 20.6 ± 4.7% of the attacking nematodes. Observations of aggressive behavior in soil assays supported our petri dish results. Moreover, larvae were observed to respond to the presence of nematodes with evasive behavior. These defense behaviors are so generalized it appears unlikely that they evolved as a specific scarab evolutionary response to selection pressure from entomopathogenic nematodes, but rather to any threat or irritant.
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variations in immune response of Popillia japonica and acheta domesticus to heterorhabditis bacteriophora and steinernema species
Journal of Nematology, 1994Co-Authors: Yi Wang, Randy GauglerAbstract:The infectivities of Steinernema carpocapsae, S. glaseri, S. scapterisci, and Heterorhabditis bacteriophora to Japanese beetle larvae, Popillia japonica, and house cricket adults, Acheta domesticus, were compared using external exposure and hemocoelic injection. Only H. bacteriophora and S. glaseri caused high P. japonica mortality after external exposure. When nematodes were injected, P. japonica had a strong encapsulation and melanization response to all species except S. glaseri. Heterorhabditis bacteriophora and S. carpocapsae were able to overcome the immune response, but S. scapterisci was not. All species except S. scapterisci were able to kill and reproduce within the host. Only S. scapterisci and S. carpocapsae caused A. domesticus mortality after external exposure. When nematodes were injected, A. domesticus had a strong immune response to all species except S. scapterisci. Steinernema carpocapsae effectively overcame the strong immune response and caused high host mortality, but S. glaseri and H. bacteriophora did not. Steinernema scapterisci caused high host mortality and reproduced, S. glaseri and H. bacteriophora caused low host mortality but only S. glaseri reproduced, and S. carpocapsae was able to kill the host but reproduced poorly. Most (ca. 90%) of the S. carpocapsae in the hemocoel of P. japonica became encapsulated and melanized within 8 hours postinjection. The symbiotic bacterium, Xenorhabduf nematophilus, was often released before this encapsulation and melanization. Key words: Acheta domesticus, encapsulation, entomopathogenic nematode, Heterorhabditis bacteriophora, immune response, melanization, Popillia japonica, Steinernema carpocapsae, S. glaseri, S. scapterisci, Xenorhabdus spp.
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penetration of steinernematid nematodes nematoda steinernematidae into japanese beetle larvae Popillia japonica coleoptera scarabaeidae
Journal of Invertebrate Pathology, 1993Co-Authors: Randy Gaugler, Yi WangAbstract:Abstract Penetration of infective juveniles of Steinernema glaseri and Steinernema carpocapsae into Japanese beetle larvae, Popillia japonica , was compared using external exposure and injection methods. Steinernematids entered the grubs through the mouth and anus, but not through the spiracles or cuticle. For all treatments, S. glaseri had higher levels of penetration than S. carpocapsae . Penetration of the gut by orally injected nematodes began 4-6 hr postinoculation. All regions of the gut were penetrated, with more than 82% of all penetrating nematodes invading the host hemocoel via the midgut. Gastric cecae were important sites for nematode penetration. Penetration sites of anally injected nematodes were the rectal sac of the hindgut. Penetration rates of isolated guts and that in vivo did not differ. Defecation by P. japonica was rapid, with orally injected nematodes appearing in the feces in 4-8 hr. Our results indicate that compared with S. glaseri, S. carpocapsae is poorly adapted to parasitize Japanese beetle larvae.
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efficacy of entomopathogenic nematode strains against Popillia japonica coleoptera scarabaeidae larvae
Journal of Economic Entomology, 1993Co-Authors: Sen Selvan, Randy Gaugler, James F CampbellAbstract:Control of Japanese beetle ( Popillia Japonica Newman) larvae by Heterorhabditis Bacteriophora Poinar (HP88 strain and a New Jersey strain, NJ-2) and Steinemema glaseri Steiner (NC strain and a New Jersey strain, NJ-43) showed that all strains reduced larval populations to a level comparable with that achieved by use of bendiocarb. Nematode strains and species did not differ significantly in mean level of population reductions ( H. bacteriophora HP88 and NJ-2, 51.0 and 71.6%; S. glaseri NC and NJ-43, 50.4 and 70.1%, respectively). However, variation in the level of population reduction provided by NJ-43 was less than that by the NC strain. After a 3-wk test period, nematode persistence and downward migration in the field did not differ among species and strains. In a laboratory bioassay, New Jersey strains provided higher levels of larval mortality compared with strains cultured in the laboratory for at least a decade. A new method used to count viable bacteria retained by individual infective juveniles showed that NJ-43 not only retained more bacteria than the NC strain (19.5 ± 0.2 compared with 4.9 ± 0.06 bacteria per infective juvenile) but also that the proportion of nematodes retaining bacteria was higher (77% compared with 55%). Bacterial retention by infective juveniles did not differ significantly between H. bacteriophora strains.
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Selection for enhanced host-finding of scarab larvae (Coleoptera, Scarabaeidae) in an entomopathogenic nematode
Environmental Entomology, 1991Co-Authors: Randy Gaugler, J. F. CampbellAbstract:The G13 strain of Steinernema carpocapsae (Weiser), previously selected for enhanced host-finding of waxmoth larvae, Galleria mellonella L., was subjected to selection for the same trait against scarab larvae. Twenty rounds of selection produced a 3.7-fold increase, from 18.4 to 68.7%, in nematode (S20 strain) location of nondiapausing larvae of the Japanese beetle, Popillia japonica Newman. However, the overall improvement over wild-types (Foundation and All strains), after 33 rounds (13 against G. mellonella and 20 against scarabs) was 153- and 72-fold, respectively. Infective juveniles had difficulty locating diapausing P. japonica larvae, and selection did not result in any enhancement in finding these larvae. Selection for host-finding of scarabs resulted in a 24.6% gain in host-finding of G. mellonella, suggesting selection was for a general feature present at different levels in different hosts. The use of KOH to absorb CO2 resulted in the complete inhibition of S20 strain response to insect hosts, verifying that nematodes have been selected for enhanced sensitivity to CO2. S20 nematodes were significantly less storage stable than the Foundation strain.
Yi Wang - One of the best experts on this subject based on the ideXlab platform.
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aggressive and evasive behaviors in Popillia japonica coleoptera scarabaeidae larvae defenses against entomopathogenic nematode attack
Journal of Invertebrate Pathology, 1994Co-Authors: Randy Gaugler, Yi Wang, James F CampbellAbstract:Larvae of the Japanese beetle, Popillia japonica , respond to attack by infective juveniles of the entomopathogenic nematode Heterorhabditis bacteriophora with aggressive and evasive behaviors. Brushing with the legs and rubbing with the abrasive raster were key aggressive behaviors associated with nematode attack in petri dish assays. Remarkably, contact with even a single live nematode triggered behavioral countermeasures directed at eliminating the attacker. Unrestrained P. japonica free to display aggressive behaviors removed more than 60% of attacking nematodes from their cuticle and experienced significantly less parasitism than larvae restrained from displaying defensive behaviors (13% or less of the nematodes removed). Unrestrained larvae were also capable of killing 20.6 ± 4.7% of the attacking nematodes. Observations of aggressive behavior in soil assays supported our petri dish results. Moreover, larvae were observed to respond to the presence of nematodes with evasive behavior. These defense behaviors are so generalized it appears unlikely that they evolved as a specific scarab evolutionary response to selection pressure from entomopathogenic nematodes, but rather to any threat or irritant.
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variations in immune response of Popillia japonica and acheta domesticus to heterorhabditis bacteriophora and steinernema species
Journal of Nematology, 1994Co-Authors: Yi Wang, Randy GauglerAbstract:The infectivities of Steinernema carpocapsae, S. glaseri, S. scapterisci, and Heterorhabditis bacteriophora to Japanese beetle larvae, Popillia japonica, and house cricket adults, Acheta domesticus, were compared using external exposure and hemocoelic injection. Only H. bacteriophora and S. glaseri caused high P. japonica mortality after external exposure. When nematodes were injected, P. japonica had a strong encapsulation and melanization response to all species except S. glaseri. Heterorhabditis bacteriophora and S. carpocapsae were able to overcome the immune response, but S. scapterisci was not. All species except S. scapterisci were able to kill and reproduce within the host. Only S. scapterisci and S. carpocapsae caused A. domesticus mortality after external exposure. When nematodes were injected, A. domesticus had a strong immune response to all species except S. scapterisci. Steinernema carpocapsae effectively overcame the strong immune response and caused high host mortality, but S. glaseri and H. bacteriophora did not. Steinernema scapterisci caused high host mortality and reproduced, S. glaseri and H. bacteriophora caused low host mortality but only S. glaseri reproduced, and S. carpocapsae was able to kill the host but reproduced poorly. Most (ca. 90%) of the S. carpocapsae in the hemocoel of P. japonica became encapsulated and melanized within 8 hours postinjection. The symbiotic bacterium, Xenorhabduf nematophilus, was often released before this encapsulation and melanization. Key words: Acheta domesticus, encapsulation, entomopathogenic nematode, Heterorhabditis bacteriophora, immune response, melanization, Popillia japonica, Steinernema carpocapsae, S. glaseri, S. scapterisci, Xenorhabdus spp.
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penetration of steinernematid nematodes nematoda steinernematidae into japanese beetle larvae Popillia japonica coleoptera scarabaeidae
Journal of Invertebrate Pathology, 1993Co-Authors: Randy Gaugler, Yi WangAbstract:Abstract Penetration of infective juveniles of Steinernema glaseri and Steinernema carpocapsae into Japanese beetle larvae, Popillia japonica , was compared using external exposure and injection methods. Steinernematids entered the grubs through the mouth and anus, but not through the spiracles or cuticle. For all treatments, S. glaseri had higher levels of penetration than S. carpocapsae . Penetration of the gut by orally injected nematodes began 4-6 hr postinoculation. All regions of the gut were penetrated, with more than 82% of all penetrating nematodes invading the host hemocoel via the midgut. Gastric cecae were important sites for nematode penetration. Penetration sites of anally injected nematodes were the rectal sac of the hindgut. Penetration rates of isolated guts and that in vivo did not differ. Defecation by P. japonica was rapid, with orally injected nematodes appearing in the feces in 4-8 hr. Our results indicate that compared with S. glaseri, S. carpocapsae is poorly adapted to parasitize Japanese beetle larvae.
James F Campbell - One of the best experts on this subject based on the ideXlab platform.
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aggressive and evasive behaviors in Popillia japonica coleoptera scarabaeidae larvae defenses against entomopathogenic nematode attack
Journal of Invertebrate Pathology, 1994Co-Authors: Randy Gaugler, Yi Wang, James F CampbellAbstract:Larvae of the Japanese beetle, Popillia japonica , respond to attack by infective juveniles of the entomopathogenic nematode Heterorhabditis bacteriophora with aggressive and evasive behaviors. Brushing with the legs and rubbing with the abrasive raster were key aggressive behaviors associated with nematode attack in petri dish assays. Remarkably, contact with even a single live nematode triggered behavioral countermeasures directed at eliminating the attacker. Unrestrained P. japonica free to display aggressive behaviors removed more than 60% of attacking nematodes from their cuticle and experienced significantly less parasitism than larvae restrained from displaying defensive behaviors (13% or less of the nematodes removed). Unrestrained larvae were also capable of killing 20.6 ± 4.7% of the attacking nematodes. Observations of aggressive behavior in soil assays supported our petri dish results. Moreover, larvae were observed to respond to the presence of nematodes with evasive behavior. These defense behaviors are so generalized it appears unlikely that they evolved as a specific scarab evolutionary response to selection pressure from entomopathogenic nematodes, but rather to any threat or irritant.
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efficacy of entomopathogenic nematode strains against Popillia japonica coleoptera scarabaeidae larvae
Journal of Economic Entomology, 1993Co-Authors: Sen Selvan, Randy Gaugler, James F CampbellAbstract:Control of Japanese beetle ( Popillia Japonica Newman) larvae by Heterorhabditis Bacteriophora Poinar (HP88 strain and a New Jersey strain, NJ-2) and Steinemema glaseri Steiner (NC strain and a New Jersey strain, NJ-43) showed that all strains reduced larval populations to a level comparable with that achieved by use of bendiocarb. Nematode strains and species did not differ significantly in mean level of population reductions ( H. bacteriophora HP88 and NJ-2, 51.0 and 71.6%; S. glaseri NC and NJ-43, 50.4 and 70.1%, respectively). However, variation in the level of population reduction provided by NJ-43 was less than that by the NC strain. After a 3-wk test period, nematode persistence and downward migration in the field did not differ among species and strains. In a laboratory bioassay, New Jersey strains provided higher levels of larval mortality compared with strains cultured in the laboratory for at least a decade. A new method used to count viable bacteria retained by individual infective juveniles showed that NJ-43 not only retained more bacteria than the NC strain (19.5 ± 0.2 compared with 4.9 ± 0.06 bacteria per infective juvenile) but also that the proportion of nematodes retaining bacteria was higher (77% compared with 55%). Bacterial retention by infective juveniles did not differ significantly between H. bacteriophora strains.
Daniel A Potter - One of the best experts on this subject based on the ideXlab platform.
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kairomones from scarabaeid grubs and their frass as cues in below ground host location by the parasitoids tiphia vernalis and tiphia pygidialis
Entomologia Experimentalis Et Applicata, 2002Co-Authors: Michael E Rogers, Daniel A PotterAbstract:Cues used in below-ground host-searching behaviour and host discrimination were examined for Tiphia vernalis Rohwer and Tiphia pygidialis Allen (Hymenoptera: Tiphiidae), ecto-parasitoids of root-feeding larvae of the Japanese beetle, Popillia japonica Newman, and masked chafers, Cyclocephala spp. (Coleoptera: Scarabaeidae), respectively. Response to potential stimuli was compared in dual choice tests in an observation chamber filled with soil. Each wasp showed species-specific, directed movement along residual body odor trails made by dragging its respective host through the soil. Presence of a grub was not necessary for wasps to follow such trails. Frass from either host- or non-host grubs elicited trail-following, but each Tiphia species followed frass trails from its respective host when a choice was presented. Frass trails elicited stronger responses than body odor trails. The combination of host frass and body odor elicited the strongest trail-following responses. Our results suggest that once in the soil, Tiphia spp. locate their hosts using contact kairomones present in grub body odor trails and frass.
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shading effects on susceptibility of rosa spp to defoliation by Popillia japonica coleoptera scarabaeidae
Environmental Entomology, 2000Co-Authors: William J Rowe, Daniel A PotterAbstract:Abstract Published anecdotal reports suggest that Japanese beetles, Popillia japonica Newman, feed more heavily on host plants growing in full sun than on shaded plants. We studied the effects of shading on foliar characteristics of roses (Rosa variety floribunda ‘Class Act’) and determined preference and fecundity of beetles provided with sun- or shade-conditioned leaves. Defoliation by P. japonica also was compared between sun-grown and experimentally shaded roses in the field. Leaves from plants grown in full sun were smaller and thicker than ones from shaded plants, with slightly higher tannins. Leaf toughness and nitrogen levels were not affected by shading, but leaves from sun-grown plants had relatively higher sugar content. Beetles consistently consumed more foliage from sun-grown plants than from shade-grown plants in laboratory preference tests. However, beetles fed continuously for 2 wk on leaves from sun- or shade-grown plants had similar fecundity. In the field, beetles fed somewhat more heav...
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absence of food aversion learning by a polyphagous scarab Popillia japonica following intoxication by geranium pelargonium hortorum
Entomologia Experimentalis Et Applicata, 1999Co-Authors: Daniel A Potter, David W HeldAbstract:It is commonly held that food-aversion learning should be more prevalent in polyphagous herbivores than in specialists. We tested the ability of Popillia japonica, a polyphagous scarab, to learn avoidance of a palatable but illness-inducing plant. Beetles that feed on flowers of geranium, Pelargonium × hortorum, became paralyzed, although most recovered within 24 h. In choice tests, naive beetles strongly preferred geranium petals over leaves of linden, Tilia cordata, a highly suitable host. Experienced beetles maintained this preference although it resulted in repeated bouts of paralysis. Fecundity was >10 times higher for beetles fed linden foliage for 2 wk than for those fed only geranium. Nevertheless, when a surplus of both foods was provided, the beetles fed mainly on geranium, resulting in greatly reduced fecundity. These results contradict the view that generalists should show propensity for food-aversion learning. Indeed, in this case, P. japonica continued to prefer the toxic plant, compromising its fitness.
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Absence of food-aversion learning by a polyphagous scarab, Popillia japonica, following intoxication by geranium, Pelargonium × hortorum
Entomologia Experimentalis Et Applicata, 1999Co-Authors: Daniel A Potter, David W HeldAbstract:It is commonly held that food-aversion learning should be more prevalent in polyphagous herbivores than in specialists. We tested the ability of Popillia japonica, a polyphagous scarab, to learn avoidance of a palatable but illness-inducing plant. Beetles that feed on flowers of geranium, Pelargonium × hortorum, became paralyzed, although most recovered within 24 h. In choice tests, naive beetles strongly preferred geranium petals over leaves of linden, Tilia cordata, a highly suitable host. Experienced beetles maintained this preference although it resulted in repeated bouts of paralysis. Fecundity was >10 times higher for beetles fed linden foliage for 2 wk than for those fed only geranium. Nevertheless, when a surplus of both foods was provided, the beetles fed mainly on geranium, resulting in greatly reduced fecundity. These results contradict the view that generalists should show propensity for food-aversion learning. Indeed, in this case, P. japonica continued to prefer the toxic plant, compromising its fitness.
