EPG Comparison of Sitobion avenae (Fab.) Feeding Behavior on Three Wheat Varieties

This article was to study the potential resistance mechanism of three different wheat varieties （Ww2730, Xiaoyan 22 and Batis） in the seedling stage to Sitobion avenae. The aphid feeding behavior was ascertained by stylet penetration activities monitoring using the electrical penetration graph （EPG） technique. When the aphids feed on Ww2730 seedlings, the time for the 1st duration probing was later than that on Xiaoyan 22 and Batis significantly, and the number of interrupted probing before the 1st duration probing was more than that on Xiaoyan 22 and Batis significantly, and the 1st duration probing was shorter than that on Xiaoyan 22 and Batis significantly. The durations of the stylet pierce from the extra- to the intra-cellular （pd Ⅱ-1） on Ww2730 and Xiaoyan 22 were longer than those on Batis significantly. The duration of the potential drop （pd） in C wave on Ww2730 was longer than that on Xiaoyan 22 and Batis significantly. The times and duration of the G wave （ingestion in xylem） on Ww2730 were more and longer than those on Xiaoyan 22 and Batis significantly. The times of spot G wave on Batis was more than that on Ww2730 significantly, but the duration of spot G was shorter than that on Xiaoyan 22 and Ww2730 significantly. The total time of E1 wave, the longest duration of E1 fractions, and the mean duration time of E1 fractions that followed E2 wave on Xiaoyan 22 and Batis were all significantly longer than those on Ww2730. There was no difference of the mean duration of the 1st E1 wave on the 3 varieties, but the mean durations of other E1 wave on Ww2730 and Xiaoyan 22 were shorter than those on Batis significantly. The other wave parameters, including times and durations of F and E2 were all not different on the 3 wheat varieties. It is suggested that the resistance mechanism of wheat variety Ww2730 to S. avenae is a restriction factor of feeding in epidermis, the thicker cell wall in mesophyll, and secondary metabolites or nutrition unbalance in phloem in the seedling phase. The resistance mechanism of Xiaoyan 22 is thicker cell wall and more cell layer in mesophyll in the seedling phase. The feeding strategy of S. avenae against the resistance of Ww2730 was to shorten the second duration of secrete watery salivation to xylem than the first.

Systematic analysis of feeding behaviors and their effects on feed efficiency in Pekin ducks

Background： Feeding behavior study is important for animal husbandry and production. However, few studies were conducted on the feeding behavior and their relationship with feeding efficiency in Pekin ducks. In order to investigate the feeding behavior and their relationship with feed efficiency and other economic traits in Pekin ducks, we selected 358 male Pekin ducks and recorded feeding information between 3 to 6 wk of age using automatic electronic feeders, and compared the feeding behavior under different residual feed intake（RFI） levels.Results： We observed that total feed time, daily feed intake and feed intake per meal had strong positive correlations with feed efficiency traits; moreover, strong correlation between feed intake per meal and body weight was found（R=0.32, 0.36）. Daily feeding rate meal and meal duration had weak correlations with feed efficiency（R=0.14~0.15）. The phenotypic correlation of between-meal pauses, with feed efficiency was not observed. When daily changes were analyzed, high RFI ducks had the highest feed consumption over all times, and obvious differences in daily visits were found among different RFI level animals during the middle period; these differences were magnified with age, but there was no difference in daily meal number. Moreover, our data indicate that high RFI birds mainly take their meals at the edge of the population enclosure, where they are more susceptible to environmental interference.Conclusions： Overal, this study suggests that the general feeding behaviors can be accurately measured using automatic electronic feeders and certain feeding behaviors in Pekin ducks are associated with improved feed efficiency.

Effects of a novel mesoionic insecticide,triflumezopyrim,on the feeding behavior of rice planthoppers,Nilaparvata lugens and Sogatella furcifera(Hemiptera:Delphacidae)

The rice planthoppers,Nilaparvata lugens and Sogatella furcifera,are important sap-sucking pests of rice in Asia.The mesoionic insecticide tifumezopyrim was previously shown to be highly effective in controlling both N.lugens and S.furcifera.In this study,electropenetrography(EPG)was used to evaluate the effect of three triflumezopyrim concentrations(LC。LC。and LC)on the feeding behavior of N.lugens and S.furcifera.EPG signals of planthoppes indicated that there were six different waveforms NP,N1,N2,N3,N4,and N5,which corresponded to non-penetration,stylet penetration into epidermis,salivation,extracellular movement of stylet,sap ingestion in phloem,and water ingestion in xylem during feeding.Compared to untreated controls,triflumezopyrim at LC。and LC。prolonged the duration of the non-penetration period by 105.3 to 333.7%.The probing frequencies of N.lugens exposed to tiflumezopyrim at LC1。and LCso were significantly increased;however,the probing frequencies of S.furcifera showed a significant decrease when exposed to triflumezopyrim at all concentrations.Triflumezopyrim exposure prolonged the duration of salivation and shortened the duration of extracellular movement.The duration of phloem sap ingestion decreased from 37.2 to 77.7%in the LCgo and LCgo treatments,respectively.Differences in feeding behavior in response to triflumezopyrim and pymetrozine were minimal.In summary,the results show that the LC。and LCgo concentrations of trflumezopyrim inhibit the feeding activities of N.lugens and S.furcifera mainly by prolonging the duration of non penetration and by shortening the duration of phloem sap ingestion,which may foster more efficient use of triflumezopyrim in Asia.

Preference, Feeding Behavior, and in Vitro Fermentation Characteristics of Pelleted Feeds Containing Alkaline Aqueous Lignin By-Product from Paper Processing in Holstein Heifers

The objectives of this study were to evaluate the effect of using multiple dietary inclusion rates of alkaline aqueous lignin by-product(AALB),in replacing a commercial binder,on the preference and feeding behavior of dairy heifers,and in vitro digestibility.In the experiment I,five pelleted diets including negative control(no-binder),commercial lignosulfonate binder,and 1.6%,3.2%,and 4.8%of AALB were tested.In the experiment II,five pelleted diets including negative control,positive control(2%molasses),and 1%,2.4%,and 3.8%of AALB(all combined with 2%of molasses)were tested.Feeding behavior and preference were determined for 60 min per animal per evaluation.In vitro digestibility was determined for each pelleted diet for 48 h over five incubation runs.Results from Experiment I showed animals receiving 1.6%of AALB diet showed the greatest preference(dry matter(DM),intake)and a greater number of approaches with eating than other diets.The preference was lower when animals received control or 4.8%AALB diets relative to other diets.Results from Experiment II revealed animals receiving 3.8%AALB combined with molasses showed the greatest DM intake preference over 60 min,and DM intake per approach.Diets that included 2.4%and 3.8%of AALB combined with molasses presented the greatest in vitro DM digestibility.Overall,heifers showed a greater intake when receiving pelleted diets with 1.6%AALB.Furthermore,preference,intake over 60 min,and in vitro DM digestibility,were greater in the pelleted diets that contained higher rates of AALB when combined with molasses.

Impact Evaluation of Insect-Resistant Transgenic Rice on the Feeding and Oviposition Behavior of Its Non-Target Insect, the Brown Planthopper, Nilaparvata lugens (Homptera: Delphacidae)

The feeding and oviposition behavior of the brown planthopper (BPH), Nilaparvata lugens on two transgenic indica rice homogenous genotypes (B1 and B6) with cry1Ab gene from Bacillus thuringiensis and transgenic restored line of hybrid rice (MSA) with SCK gene (a modified CpTI gene) were measured, compared with those on their corresponding non transgenic parental cultivars Jiazao935 and Minghui86 performed by BPH. Under the selection condition of host plants by BPH, loading percentage, oviposition preference and laying egg number of BPH both on transgenic cry1Ab rice and transgenic SCK rice were not significantly different from those on their controls, while their total number of probing wound caused by PBH expect for feeding on B1 plants was markedly more than that on the control. In contrast, under the non selection condition, total number of probing wound caused by BPH on either transgenic cry1Ab rice or transgenic SCK rice was pronouncedly more than those on their controls. Conversely, their honeydew amount excreted by BPH after feeding for 24 h was significantly less than those on the control. As a conclusion, three tested transgenic rice genotypes with insect resistance acted adverse effect on BHP feeding, and no marked effect on BPH oviposition.

Geomagnetic field absenee reduces adult body weight of a migratory insect by disrupt!ng feeding behavior and appetite regulation

The geomagnetic field(GMF)is well documented for its essential role as a cue used in animal orientation or navigation.Recent evidence indicates that the absence of GMF(mimicked by the near-zero magnetic field,NZMF)can trigger stress-like responses such as reduced body weight,as we have previously shown in the brown planthopper,Nilaparvata lugens.In this study,we found that consistent with the significantly decreased body weight of newly emerged female(—14.67%)and male(—13.17%)adult N.lugens,the duration of the phloem ingestion feeding waveform was significantly reduced by 32.02%in 5th instar nymphs reared under the NZMF versus GMF.Interestingly,5th instar nymphs that exhibited reduced feeding had significantly higher glucose levels(+16.98%and+20.05%;24 h and 48 h after molting),which are associated with food aversion,and expression patterns of their appetite-related neuropeptide genes(neuropeptide F,dow regulated overall;short neuropeptide F,dowregulated overall;adipokinetic hormone up-regulated overall;and adipokinetic hormone receptor,down-regulated overall)were also altered under the absence of GMF in a manner consistent with diminishing appetite.Moreover,the expressions of the potential magnetosensor croptochromes(Crys)were found significantly altered under the absence of GMF,indicating the likely upstream signaling of the Cry-mediated magnetoreception mechanisms.These findings support the hypothesis that strong changes in GMF intensity can reduce adult body weight through affecting insect feeding behavior and underlying regulatory processes including appetite regulation.Our results highlight that GMF could be necessary for the maintenanee of energy homeostasis in insects.

Stressful living in lower-quality habitats?Body mass,feeding behavior and physiological stress levels in wild wood mouse populations

Wild populations are continuously subjected to changes in environmental factors that pose different challenges.Body condition and hormones have been commonly used as health indicators due to their potential correlation with fitness.In the present study,we analyzed whether habitats of different quality influenced body mass,food intake and physiological stress levels in wild wood mice(Apodemus sylvaticus).Field work was seasonally carried out in Holm oak woods and pine forests in central Spain.A total of 93 wood mice from 4 different populations(2 per habitat type)were live-trapped.From each captured individual we noted body mass and food intake,measured as the amount of bait remaining in each trap.The physiological stress levels were measured non-inva-sively in collected fresh feces by quantifying fecal corticosterone metabolites(FCM)with a 5a-pregnane-3ß,11ß,21-triol-20-one enzyme immunoassay.Wood mice abundances decreased from spring to summer,were higher in Holm oak woods than in pine forests and also resulted in different age-class distribution between both habitats.Individuals inhabiting pine forests showed a lower body mass and increased food intake,probably because of the comparatively lower food quality and availability in this habitat.Furthermore,these individuals showed increased physiological stress levels,likely due to the lower quality habitat in relation to both food and vegetation cover availability.Overall,besides affecting local wood mouse abundance,our study underscores the effect of habitat quality on body mass,food intake and the endocrine stress response.Considering the wood mouse’s piv-otal position in ecosystems,these results could help in the understanding of environmental traits hampering the viability of wild populations.

The human-derived novel gut commensal Luoshenia tenuis regulates body weight and food intake in mice

Many studies have revealed that gut microbes modulate host metabolism.In this study,we characterized the therapeutic effects of a novel gut commensal Luoshenia tenuis against host metabolic disorders.First,by in silico analysis,we demonstrated that the L.tenuis was prevalent in the gut microbiomes of healthy humans but were depleted specifically in obesity cohorts.Further in vitro cultivation revealed that L.tenuis produced short chain fatty acids that were verified to modulate host metabolism and some other volatile metabolites to benefit hosts by anti-inflammation and anti-tumor.Second,gavage of the L.tenuis significantly decreased the body weight gain and food intake of high-fat diet-feeding C57BL/6J mice,which was in parallel with the changed expression level of genes related to satiety and feeding behavior.We then performed the gavage trial using diet induced obese mice,and it revealed that the administration of L.tenuis alleviated significantly the abnormal glucose and lipid metabolisms and reduced the inflammatory response.In summary,this study revealed a previously-unknown human gut commensal microbe that benefited host metabolism,and set the stage for the development of novel next-generation probiotic applicable for treatment of obesity and related metabolic disorders.

916 MHz electromagnetic field exposure affects rat behavior and hippocampal neuronal discharge

Wistar rats were exposed to a 916 MHz, 10 W/m2 mobile phone electromagnetic field for 6 hours a day 5 days a week. Average completion times in an eight-arm radial maze were longer in the exposed rats than control rats after 4-5 weeks of exposure. Error rates in the exposed rats were greater than the control rats at 6 weeks. Hippocampal neurons from the exposed rats showed irregular firing patterns during the experiment, and they exhibited decreased spiking activity 6-9 weeks compared with that after 2 5 weeks of exposure. These results indicate that 916 MHz electromagnetic fields influence leaming and memory in rats during exposure, but long-term effects are not obvious.

Genetic parameters of drinking and feeding traits of wean-to-finish pigs under a polymicrobial natural disease challenge

Background:The pork industry faces unprecedented challenges from disease,which increases cost of production and use of antibiotics,and reduces production efficiency,carcass quality,and animal wellbeing.One solution is to improve the overall resilience of pigs to a broad array of common diseases through genetic selection.Behavioral changes in feeding and drinking are usually the very first clinical signs when animals are exposed to stressors such as disease.Changes in feeding and drinking behaviors in diseased pigs may reflect the way they cope with the challenge and,thus,could be used as indicator traits to select for disease resilience.The objectives of this study were to estimate genetic parameters of feeding and drinking traits for wean-to-finish pigs in a natural polymicrobial disease challenge model,to estimate genetic correlations of feeding and drinking traits with growth rate and clinical disease traits,and to develop indicator traits to select for disease resilience.Results:In general,drinking traits had moderate to high estimates of heritability,especially average daily water dispensed,duration,and number of visits(0.44 to 0.58).Similar estimates were observed for corresponding feeding traits(0.35 to 0.51).Most genetic correlation estimates among drinking traits were moderate to high(0.30 to 0.92)and higher than among feeding traits(0 to 0.11).Compared to other drinking traits,water intake duration and number of visits had relatively stronger negative genetic correlation estimates with treatment rate and mortality,especially across the challenge nursery and finisher(−0.39 and−0.45 for treatment rate;−0.20 and−0.19 for mortality).Conclusion:Most of the recorded drinking and feeding traits under a severe disease challenge had moderate to high estimates of heritability,especially for feed or water intake duration and number of visits.Phenotypic and genetic correlations among the recorded feeding traits under disease were generally low but drinking traits showed high correlations with each other.Water intake duration and number of visits are potential indicator traits to select for disease resilience because of their high heritability and had moderate genetic correlations with treatment and mortality rates under severe disease.

Food and Nutritional Security in the Refugee Women’s Life Narratives

Objective: To understand, based on the life narratives of refugee women, food and nutritional security. Method: Qualitative, descriptive, exploratory study, Narratives of life method, by Daniel Bertaux. Conducted with 11 participants, refugee women residing in the state of Rio de Janeiro, Brazil. Results: The meanings and feelings evidenced in the life narratives of refugee women expressed the insecurities and weaknesses with food in the resettlement. Final Considerations: Given the meanings and feelings regarding food in the refuge, it is expected that the present study will contribute to the elaboration of new action plans and intersectoral public policies of agile action to meet the demands of the refugee population, in the attempt to mitigate starvation, poverty, social differences and the compromised health status of the refugee population.

Insect-specific RNA virus affects the stylet penetration activity of brown citrus aphid(Aphis citricidus)to facilitate its transmission

Sap-sucking insects often transmit plant viruses but also carry insect viruses,which infect insects but not plants.The impact of such insect viruses on insect host biology and ecology is largely unknown.Here,we identified a novel insect-specific virus carried by brown citrus aphid(Aphis citricidus),which we tentatively named Aphis citricidus picornavirus(AcPV).Phylogenetic analysis discovered a monophyletic cluster with AcPV and other unassigned viruses,suggesting that these viruses represent a new family in order Picornavirales.Systemic infection with AcPV triggered aphid antiviral immunity mediated by RNA interference,resulting in asymptomatic tolerance.Importantly,we found that AcPV was transmitted horizontally by secretion of the salivary gland into the feeding sites of plants.AcPV influenced aphid stylet behavior during feeding and increased the time required for intercellular penetration,thus promoting its transmission among aphids with plants as an intermediate site.The gene expression results suggested that this mechanism was linked with transcription of salivary protein genes and plant defense hormone signaling.Together,our results show that the horizontal transmission of AcPV in brown citrus aphids evolved in a manner similar to that of the circulative transmission of plant viruses by insect vectors,thus providing a new ecological perspective on the activity of insect-specific viruses found in aphids and improving the understanding of insect virus ecology.

Frequent and prolonged nocturnal occupation of port areas by Yangtze finless porpoises (Neophocaena asiaeorientalis): Forced choice for feeding?

During the Yangtze Freshwater Dolphin Expedition 2012,Yangtze finless porpoises(Neophocaena asiaeorientalis)were acoustically monitored in 9 port areas at night.During 6566 min of nocturnal monitoring,porpoise sonar was detected for 488 min(7.43%of the total time).Of all 81 encounters,the longest echolocation span obtained was 102.9 min,suggesting frequent and prolonged porpoise occupation of the port areas.A combined total of 2091 click trains were recorded,with 129(6.2%)containing minimum inter-click intervals(ICIs)below 10 ms(termed a buzz).Buzzes with a decrease in ICIs and search and approach phases that resembled feeding echolocation signals accounted for 44.2%(N=52)of all buzzes.Buzzes with an increase in ICIs,suggesting a mirrored prey capture phase,accounted for 20.2%(N=26)and could reflect attempts to locate escaped prey because they were followed by approach-phase feeding buzzes.Anecdotal evidence of porpoises fleeing the proximity of vessels was observed.The recordings indicating clusters of porpoises feeding near the port areas suggest a forced choice for feeding due to the relatively higher prey availability in the port areas compared to other areas in the Yangtze River that are probably overfished.

Stylet penetration behaviors of the cotton aphid Aphis gossypfi on transgenic Bt cotton

Stylet penetration behaviors of cotton aphids Aphis gossypii Glover on a transgenic cotton line ＂GK-12＂ expressing Bt toxic protein of Cry 1A （Bt cotton） and a non- Bt conventional cotton line ＂Simian-3＂ （CK cotton） were recorded with the direct current electrical penetration graph （DC-EPG） technique. Cotton aphids reared on Bt cotton （abbreviated as Bt-aphids） and its parental non-Bt control line （CK-aphids） for more than 20 generations each, were used for recordings on two cotton lines. Among 47 selected parameters reflecting the activities of aphid stylets within plant tissues, there were eight parameters of CK-aphids showing significant differences between the performances of CK- aphids on Bt cotton and CK cotton, while for Bt-aphids, all the parameters were statistically equal between the performances on the two cotton lines. All parameters with significant differences indicated that CK-aphids could penetrate into Bt cotton more easily, but the phloem saps of Bt cotton were not as good as those of regular cotton for CK-aphids. Based on the present results, we concluded that there were some factors in Bt cotton affecting penetration behaviors of CK-aphids, but it just took several generations for CK-aphids to completely adapt Bt cotton, and Bt-aphids could feed on two cotton lines without difficulty.

Ultrastructure of compatible and incompatible interactions in phloem sieve elements during the stylet penetration by cotton aphids in melon

Resistance of the melon line TGR-1551 to the aphid Aphis gossypii is based on preventing aphids from ingesting phloem sap. In electrical penetration graphs （EPGs）, this resistance has been characterized with A. gossypii showing unusually long phloem salivation periods （waveform El） mostly followed by pathway activities （waveform C） or if followed by phloem ingestion （waveform E2）, ingestion was not sustained for more than 10 min. Stylectomy with aphids on susceptible and resistant plants was performed during EPG recording while the stylet tips were phloem inserted. This was followed by dissection of the penetrated leaf section, plant tissue fixation, resin embedding, and ultrathin sectioning for transmission electron microscopic observation in order to study the resistance mechanism in the TGR. The most obvious aspect appeared to be the coagulation of phloem proteins inside the stylet canals and the punctured sieve elements. Stylets of 5 aphids per genotype were amputated during sieve element （SE） salivation （El） and SE ingestion （E2）. Cross-sections of stylet bundles in susceptible melon plants showed that the contents of the stylet canals were totally clear and also, no coagulated phloem proteins occurred in their punctured sieve elements. In contrast, electron-dense coagulations were found in both locations in the resistant plants. Due to calcium binding, aphid saliva has been hypothesized to play an essential role in preventing/suppressing such coagulations that cause occlusion of sieves plate and in the food canal of the aphid＇s stylets. Doubts about this role of E 1 salivation are discussed on the basis of our results.

Sieve element occlusion provides resistance against Aphis gossypii in TGR-1551 melons

Feeding behavior and plant response to feeding were studied for the aphid Aphis gossypii Glover on susceptible and resistant melons(cv.Iroquois and TGR-1551,respectively).Average phloem phase bout duration on TGR-1551 was<7% of the duration on Iroquois.Sixty-seven percent of aphids on TGR-1551 never produced a phloem phase that attained ingestion(EPG waveform E2)in contrast to only 7% of aphids on Iroquois.Average bout duration of waveform E2(scored as zero if phloem phase did not attain E2)on TGR-1551 was<3% of the duration on Iroquois.Conversely,average bout duration of EPG waveform El(sieve element salivation)was 2.8 times greater on TGR-1551 than on Iroquois.In a second experiment,liquid nitrogen was used to rapidly cryofix leaves and aphids within a few minutes after the aphids penetrated a sieve element.Phloem near the penetration site was then examined by confocal laser scanning microscopy.Ninety-six percent of penetrated sieve elements were occluded by protein in TGR-1551 in contrast to only 28% in Iroquois.Usually in TGR-1551,occlusion was also observed in nearby nonpenetrated sieve elements.Next,a calcium channel blocker,trivalent lanthanum,was used to prevent phloem occlusion in TGR-1551,and A.gossypii feeding behavior and the plants phloem response were compared between lanthanum-treated and control TGR-1551.Lanthanum treatment eliminated the sieve element protein occlusion response and the aphids readily ingested phloem sap from treated plants.This study provides strong evidence that phloem occlusion is a mechanism for resistance against A.gossypii in TGR-1551.

Subterranean termites （Isoptera： Rhinotermitidae）： Exploitation of equivalent food resources with different forms of placement

Coptotermes gestroi and Heterotermes tenuis have been described as important urban pests in Brazil. The establishment of control technologies using baits that consider the social behavior of termites requires a better knowledge of their foraging behavior. Thus, this study analyzed the feeding behavior of these species with three different forms of food placement： food on the surface of a substrate and food either partially or completely buried in the substrate. Experimental arenas were composed of a central chamber connected to three food chambers. Each central chamber contained 550 foragers of C. gestroi or 517 foragers of 11. tenuis. Blocks of Pinus elliottii were placed in the different food chambers. After 28 days, the consumption of each wood block and the percentage of foraging individuals recruited for food chambers were verified in relation to the total survival rate obtained for each one of the 20 replicates. Results showed that completely buried food was most consumed for H. tenuis and presented a higher recruitment rate of workers and soldiers for both species. Although the consumption had non-significant differences for C. gestroi, these termites exhibited a tendency to prefer completely buried food. In these conditions, it can be concluded that the forms of food placement used in the present research influenced the recruitment of individuals for both species. Data also suggests that when the foraging subterranean termites find food resources in the tunneling substrate, they tend to concentrate their efforts on it, a behavior regime that reduces exposure to external environment.

Food preference of the rove beetle, Atheta coriaria Kraatz （Coleoptera： Staphylinidae） under laboratory conditions

A study, involving laboratory choice tests, was conducted to determine the feeding behavior, based on food preference, of the adult and larval stage of the rove beetle, Atheta coriaria Kraatz when presented with both fresh moistened oatmeal and second instar fungus gnat, Bradysia sp. nr. coprophila （Lintner） larvae in Petri dishes. Rove beetles used in this study came from a laboratory-reared colony. A rating scale from 1 to 5, based on percent missing （1 = 0 to 10%, 2 = 11 to 30%, 3 = 31 to 50%, 4 = 51 to 75%, and 5 = 76 to 100%）, was used to objectively assess the amount of oatmeal and number of fungus gnat larvae consumed by each rove beetle adult and larva. In all the choice tests, A. coriaria adults and larvae preferred to feed on fungus gnat larvae （78% and 69%, respectively） significantly more so than oatmeal （9% and 5%, respectively） based on the amount of oatmeal and number of fungus gnat larvae consumed after 4 and 6 hours. There were relatively minimal differences in the amount of food consumed for both adults and larvae after 4 and 6 hours. The results of this study indicate that oatmeal may be an inexpensive supplemental food source, during the rearing process, which will not inhibit the effectiveness of rove beetles to control fungus gnat larvae when released into greenhouses.

Development of defoliating insects and their preferences for host plants under varying temperatures in a subtropical evergreen forest in eastern China

Abstract The aim of this work was to understand the development of defoliating insects and their preferences for host plants under varying temperatures in a subtropical evergreen broad-leaved forest in China. We measured the main developmental parameters of three typical defoliating insects （i.e., Ourapteryx ebuleata szechuana, Biston marginata, and Euproctis angulata） and their preferences for five host plants at temperatures from 16~C to 31 ~C at 3~C intervals in the Tiantong National Forest Research station in eastern China. The results showed the following. 1） An appropriate rise in temperature increases the survival rate with an increase in the number of offspring. The developmental durations for these three insects were shortened, and pupal weight increased with an increase in temperature. 2） A shift in the preference for host plants for these three insects was observedat elevated tempera- tures. They all preferred to feed on Schima superba and Castanopsis sclerophylla at elevated temperatures, show- ing an opposite response to the other three plants. The daily leaf consumption of the three insects was positively correlated with their feeding preference, with more leaves being consumed from the plants they preferred. 3） For O. ebuleata szechuana larvae, daily leaf consumption initially increased and then decreased with increasing temperatures. In contrast, Biston marginata and Euproctis angulata larvae consumed more leaves at elevated temperatures. The feeding preferences of O. ebuleata szechuana and Biston marginata were more sensitive to changing temperatures than that of Euproctis angulata laevae. We concluded that increased numbers of offspring and generations, pupal weights, and a shift in preference to two plants for these three defoliating insects might lead to severe damage to these two plants which would enhance the fragmentation and decrease the stability of the forest communities under changing temperatures. Meanwhile, the variations in the responses of defoliating insects to the changing temperatures should be taken into consideration for the pest management of forests to adapt to the changing climate.