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Insect Science 2011年第1期18卷 84-91页

作者： Chen Luo tong-xian Liu Institute of Plant and Environment Protection Beijing Academy of Agriculture and Forestry Sciences Beijing Key Laboratory of Applied Entomology Northwest A&F University Yangling Shaanxi Province China

Fitness and efficacy of Encarsia sophia （Girault ＆ Dodd）（Hymenoptera： Aphelinidae） as a biological control agent was compared on two species of whitefly （Hemiptera： Aleyrodidae） hosts, the relatively smaller sweetpotato whitefly, Bemisia tabaci （Gennadius） biotype ＇B＇, and the larger greenhouse whitefly, Trialeurodes vaporariorum （Westwood）. Significant differences were observed on green bean （Phaseolus vulgaris L.） in the laboratory at 27 ± 2℃, 55% 4- 5% RH, and a photoperiod of 14 ： 10 h （L ： D）. Adult parasitoids emerging from T. vaporariorum were larger than those emerging from B. tabaci, and almost all biological parameters of E. sophia parasitizing the larger host species were superior except for the developmental times of the parasitoids that were similar when para- sitizing the two host species. Furthermore, parasitoids emerging from T. vaporariorum parasitized more of these hosts than did parasitoids emerging from B. tabaci. We conclude that E. sophia reared from larger hosts had better fitness than from smaller hosts. Those from either host also preferred the larger host for oviposition but were just as effective on smaller hosts. Therefore, larger hosts tended to produce better parasitoids than smaller hosts.

关键词： biological control body size host size oviposition sweetpotato whitefly

High-quality voice conversion system based on GMM statistical parameters and RBF neural network

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The Journal of China Universities of Posts and Telecommunications 2014年第5期21卷 68-75,93页

作者： CHEN xian-tong ZHANG Ling-hua College of Telecommunications and Information Engineering Nanjing University of Posts and Telecommunications

A voice conversion （VC） system was designed based on Gaussian mixture model （GMM） and radial basis function （RBF） neural network. As a voice conversion model, RBF network needs quantities of training data to improve its performance. For one speech, the networks trained by different segments of data have different transformation effects. Since trying segment by segment to obtain the best conversion effect is complex, a conversion method was proposed, that uses GMM for statistics before training RBF network to aim at the problem. The speech transformation and representation using adaptive interpolation of weighted spectrum （STRAIGHT） model is used for accurate extraction of vocal tract spectrum. Then GMM is used to classify the numerous spectral parameters. The obtained mean parameters were trained in RBF network. Experiment reveals that, the soft classification ability of GMM can promptly realize the reduction and classification of training data under the premise of ensuring the training effect. The selection complexity is decreased thereafter. Compared to the conventional RBF network training methods, this method can make the transformation of spectral parameters more effective and improve the quality of converted speech.

关键词： VC system STRAIGHT vocal tract spectrum GMM RBF

Oviposition preference, larval performance and adaptation of Trichoplusia ni on cabbage and cotton

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Insect Science 2015年第2期22卷 273-282页

作者： Yuan-Xi Li tong-xian Liu Department of Entomology College of Plant Protection Nanjing Agricultural University Nanjing State Key Laboratory of Crop Stress Biology for Arid Areas and Key Laboratory of Crop IPM for the Loess Plateau Ministry of Agriculture of China at Northwest A&F University Yangling Shaanxi China

Most female herbivores ensure to lay eggs where their offspring can develop successfully. The oviposition preferences of females affect strategies in pest management. In this study, the performance of two cohorts of Trichoplusia ni larvae on cabbage and cotton （after they had been transferred from their original host plants） were investigated. The preferences of female moth ovipositing and larval feeding on these two host plants were observed. The results indicated that plants significantly affected oviposition preference of the female adults and development and survival of larvae of T. ni. All females preferred to lay eggs on cabbage than cotton regardless from which host they originated. The detrimental effects of cotton on the development and survival of T. ni larvae originated from cabbage （CaTn） increased with the increase of the larval age when they were transferred. In addition, the host plant change did not significantly affect the development and survival of larvae of T. ni originating from cotton （CoTn）. Larvae of CaTn preferred cabbage plants as compared to cotton plants, whereas larvae of CoTn did not show a significant choice. Although the adult females preferred laying eggs on cabbage, they did not show preferences between cotton and cabbage in a Y-tube olfactometer test. The hypothesis of oviposition preference and performance of larvae was supported by the results of CaTn, whereas they not supported by those from CoTn. Based on these results, the strategy to manage this serious pest was discussed.

关键词： cabbage looper development larval choice oviposition preference

Avoidance of parasitized host by female wasps of Aphidius gifuensis (Hymenoptera:Braconidae):The role of natal rearing effects and host availability?

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Insect Science 2018年第6期25卷 1035-1044页

作者： Ming-Zhen Pan tong-xian Liu Christian Nansen Key Laboratory of Integrated Pest Management in Crops Ministry of Agriculture /Institute of Plant ProtectionChinese Academy of Agricultural SciencesSine-American Biological Control LaboratoryBeijingChina State Key Laboratory of Crop Stress Biology for Arid Areas and Key Laboratory of Northwest Loess Plateau Crop Pest Management of Ministry of AgricultureNorthwest A and F UniversityYanglingShaanxiChina Department of Entomology and Nematology University of California DavisCAUSA

Natal rearing experience of animals may affect their behaviors,such as habitat selection and oviposition *** part of the overall fitness of insect parasitoids, successful host discrimination (distinguishing parasitized hosts from unparasitized hosts) is of paramount *** this study we examined whether and how parasitoids' natal rearing experience would affect their host discrimination ability according to host *** established separate colonies ofAphidius gifuensis Ashmead by continual rearing on two hosts,Sitobion avenae E and Myzuspersicae (Suzler),and quantified self superparasitism and self superparasitism versus parasitism ratio for the four:combinations ofparasitoid colonies and host species (*** and ***)at four host densities (30,50,100 or 150 per plant).Results showed that self superparasitism *** by *** reared on *** was significantly higher than by those reared on ***,no matter whether the host densities were 30,50,100 or *** gifuensis reared on *** significantly superparasitized more *** than those reared on *** only when host density was *** superparasitism versus parasitism ratio of *** from both colonies was always lower on natal hosts than on new hosts,and the difference was more pronounced as the host density *** results suggested that natal rearing effects is important on host discrimination and oviposition decision of the parasitoid *** effects promoted the parasitoid's host adaptation and made them confer greater fitness.

关键词： host discrimination Myzus persicae self superparasitism Sitobion avenae

Jasmonate- and salicylate-induced defenses in wheat affect host preference and probing behavior but not performance of the grain aphid, Sitobion avenae

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Insect Science 2014年第1期21卷 47-55页

作者： He-He Cao Su-Hua Wang tong-xian Liu State Key Laboratory of Crop Stress Biology on the Arid Areas and the Key Laboratory of Crop Pest Management on the Losses Plateauof Ministry of Agriculture Northwest A&F University Yangling Shaanxi China

Jasmonate and salicylatemediated signaling pathways play significant roles in induced plant defenses, but there is no sufficient evidence for their roles in monocots against aphids. We exogenously applied methyl jasmonate （MeJA） and salicylic acid （SA） on wheat seedlings and examined biochemical responses in wheat and effects on the grain aphid, Sitobion avenae （Fab.）. Application of MeJA significantly increased levels of wheat＇s polyphenol oxidase, peroxidase and proteinase inhibitor 1, 2 and 6 days after treatment. In twochoice tests, adult aphids preferred control wheat leaves to MeJA or SA treated leaves. Electrical penetration graph （EPG） recordings of aphid probing behavior revealed that on MeJAtreated plants, the duration of aphid＇s first probe was significantly shorter and number of probes was significantly higher than those on control plants. Also total duration of probing on MeJAtreated plants was significantly shorter than on control plants. Total duration of salivation period on SAtreated plants was significantly longer, while mean phloem ingestion period was significantly shorter than on control plants. However, no significant difference in total duration of phloem sap ingestion period was observed among treatments. The EPG data suggest that MeJAdependent resistance factors might be due to feeding deterrents in mesophyll, whereas the SAmediated resistance may be phloembased. We did not observe any significant difference of MeJA and SA application on aphid development, daily fecundity, intrinsic growth rate and population growth. The results indicate that both MeJA and SAinduced defenses in wheat deterred S. avenae colonization processes and feeding behavior, but had no significant effects on its performance.

关键词： cereal aphids EPG induced plant defense methyl jasmonate salicylic acid

Effects of selected insecticides on adults of two parasitoid species of Liriomyza trifolii： Ganaspidium nigrimanus （Figitidae） and Neochrysocharis formosa （Eulophidae）

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Insect Science 2011年第5期18卷 512-520页

作者： Ricardo Hernandez Kun Guo Marvin Harris tong-xian Liu Texas AgriLife Research Texas A＆M University System Weslaco Department of Entomology Texas A＆M University College Station Texas USA Key Laboratory of Applied Entomology Northwest A＆F University Yangling Shaanxi Institute of Medicinal Plant Development Chinese Academy of Medical Sciences Peking Union Medical College Beijing China

Liriomyza trifolii is an important pest of vegetables and ornamental crops around the world. This pest is attacked by many parasitoid species. The principal management tactic used against L. trifolii is insecticide application. Insecticides vary in their effects on parasitoid species and insecticides that have less harmful effects should be preferred for the control of this pest. In this study, novaluron, abamectin, λ-cyhalothrin and spinetoram were investigated for their lethal effects on adults of Neochrysocharisformosa and Ganaspidium nigrimanus, two important parasitoids ofL. trifolii. Three different bioassays were used on adult parasitoids： direct insecticide application, insecticide intake and insecticide residue. Adult parasitoid response to novaluron exhibited the least lethal effects among the bioassays and insecticides tested. Abamectin had significant mortality to both parasitoid species in the direct application and insecticide intake bioassays and mortality were high for G. nigrimanus in the residue bioassay. Spinetoram was the most harmful insecticide to the adult parasitoids in all three bioassays. λ-cyhalothrin effects varied between the two parasitoids. In the direct application, it was harmful to G. nigrimanus and had no effect on N. formosa. In the insecticide intake bioassay λ-cyhalothrin had no effect in survival of either species, and in the residue bioassay it reduced parasitoid survival of both species. Potential tolerance of N. formosa to λ-cyhalothrin is discussed.

关键词： biological control insecticides leafminers parasitoids

Zebra chip disease incidence on potato is influenced by timing of potato psyllid infestation, but not by the host plants on which they were reared

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Insect Science 2009年第5期16卷 399-408页

作者： Feng Gao John Jifon xiangbing Yang tong-xian Liu Texas AgriLife Research Texas A&M University System 2415 E. Highway 83 Weslaco TX 78596 USA

The Zebra chip （ZC） syndrome is an emerging disease of potato and a major threat to the potato industry. The potato psyllid, Bactericerca cockerelli （Sulc） is believed to be a vector of the ZC pathogen, which is now thought to be Candidatus Liberibacter, a bacterium. To further understand the relationship between potato psyllid infestation and ZC disease expression, healthy potato plants at different growth stages （4, 6 and 10 weeks after germination） were exposed separately to potato psyllids that were separately reared on four solanaceous hosts plants （potato, tomato, eggplant or bell pepper） for more than 1 year. ZC symptoms, leaf rates and total nonstructural carbohydrate accumulation in leaves and tubers of healthy and psyllid-infested plants were monitored and recorded. Typical ZC symptoms were observed in leaves and tubers of all plants exposed to potato psyllids regardless of the host plant on which they were reared. This was also accompanied by significant reductions in net photosynthetic rate. Caged potato plants without exposure to potato psyllids （uninfested controls） did not show any ZC symptom in both foliage and in harvested tubers. Foliage damage and ZC expression were most severe in the potato plants that were exposed to potato psyllids 4 weeks after germination compared to plants infested at later growth stages. Tubers from potato psyllid-infested plants had significantly higher levels of reducing sugars （glucose） and lower levels of starch than those in healthy plants, indicating that potato psyllid infestation interfered with carbohydrate metabolism in either leaves or tubers, resulting in ZC expression.

关键词： Bactericerca cockerelli glucose reducing sugars starch sucrose zebra chip disease

Impact of scandium and terbium on the mechanical properties,corrosion behavior,and biocompatibility of biodegradable Mg-Zn-Zr-Mn alloys

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Journal of Magnesium and Alloys 2024年第2期12卷 546-572页

作者： Khurram Munir Jixing Lin xian tong Arne Biesiekierski Yuncang Li Cuie Wen School of Engineering RMIT UniversityMelbourneVictoria 3001Australia School and Hospital of Stomatology Wenzhou Medical UniversityWenzhou 325027China

Magnesium(Mg)-based bone implants degrade rapidly in the physiological environment of the human body which affects their structural integrity and biocompatibility before adequate bone *** earth elements(REEs)have demonstrated their effectiveness in tailoring the corrosion and mechanical behavior of Mg *** study methodically investigated the impacts of scandium(Sc)and terbium(Tb)in tailoring the corrosion resistance,mechanical properties,and biocompatibility of Mg–0.5Zn–0.35Zr–0.15Mn(MZZM)alloys fabricated via casting and hot *** indicate that addition of Sc and Tb improved the strength of MZZM alloys via grain size reduction and solid solution strengthening *** extruded MZZM–(1–2)Sc–(1–2)Tb(wt.%)alloys exhibit compressive strengths within the range of 336–405 MPa,surpassing the minimum required strength of 200 MPa for bone implants by a significant *** polarization tests revealed low corrosion rates of as–cast MZZM(0.25 mm/y),MZZM–2Tb(0.45 mm/y),MZZM–1Sc–1Tb(0.18 mm/y),and MZZM–1Sc–2Tb(0.64 mm/y),and extruded MZZM(0.17 mm/y),MZZM–1Sc(0.15 mm/y),MZZM-2Sc(0.45 mm/y),MZZM-1Tb(0.17 mm/y),MZZM-2Tb(0.10 mm/y),MZZM–1Sc-1Tb(0.14 mm/y),MZZM-1Sc-2Tb(0.40 mm/y),and MZZM–2Sc–2Tb(0.51 mm/y)alloys,which were found lower compared to corrosion rate of high-purity Mg(~1.0 mm/y)reported in the ***,addition of Sc,or Tb,or Sc and Tb to MZZM alloys did not adversely affect the viability of SaOS2 cells,but enhanced their initial cell attachment,proliferation,and spreading shown via polygonal shapes and *** study emphasizes the benefits of incorporating Sc and Tb elements in MZZM alloys,as they effectively enhance corrosion resistance,mechanical properties,and biocompatibility simultaneously.

关键词： Corrosion property In vitro cytotoxicity Magnesium alloys Mechanical property Rare earth elements

Morphological traits for sex identification of the oriental armyworm,Mythimna separata(Lepidoptera:Noctuidae)

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Journal of Integrative Agriculture 2020年第6期19卷 1458-1463页

作者： CHEN Lin PAN Qin-jian Muhammad Saad WAQAS LIU tong-xian State Key Laboratory of Crop Stress Biology for Arid Areas/Key Laboratory of Integrated Pest Management on the Loess Plateau Ministry of AgricultureNorthwest A&F UniversityYangling 712100P.R.China State Key Laboratory of Rice Biology/MOA Key Lab of Molecular Biology of Crop Pathogens and Insects/Institute of Insect Sciences Zhejiang UniversityHangzhou 310058P.R.China

The oriental armyworm,Mythimna separata(Lepidoptera:Noctuidae)is a harmful pest which causes heavy loss in agricultural *** identification of *** is very important for understanding the biology and management of this *** of fast and convenient methods to identify *** female and male is the necessary prerequisite for con ducting gender-related *** this study,new methods to differentiate sex of *** at pupal and adult stages were *** results showed that posterior abdominal segments containing genital organs which are morphological traits to differentiate female and *** openings are important characters for the female and male pupae *** female pupa,it locates on the ventral side of eighth and ninth abdominal segments and appears as a visible longitudinal suture;for male pupa,it locates on the ventral side of the ninth abdominal segment and appears as a short slit surrounded by a pair of visible semicircular *** numbers are another indicator for sex differentiation of *** female has three-bristled frenulum and each male has one bristled-frenulum near the base of hind wing of each side of moth *** confirmed the two sex differentiation methods manually by dissecting genitalia of adults and found their genger was as same as what we examined the sex of pupae and adults using the morphological methods.

关键词： sex identification pupa and adult genital opening frenulum genitalia

Host permissiveness to baculovirus in flue nces time-dependent immune responses and fitness costs

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Insect Science 2021年第1期28卷 103-114页

作者： Qinjian Pan Ikkei Shikano Gary WFelton tong-xian Liu Kelli Hoover State Key Laboratory of Crop Stress Biology for Arid Areas and Key Laboratory of Integrated Pest Management on the Loess Plateau of Ministry of AgricultureNorthwest A&F UniversityYanglingShaanxiChina Department of Entomology and Center for Chemical Ecology Pennsylvania State UniversityUniversity ParkPAUSA Department of Plant and Environmental Protection Sciences University of Hawaii at ManoaHonoluluHIUSA

Insects possess specific immune responses to protect themselves from different types of *** of immune cascades can inflict significant developmental costs on the surviving *** characterize infection kinetics in a surviving host that experiences baculovirus inoculation,it is crucial to determine the timing of immune ***,we investigated time-dependent immune responses and developmental costs elicited by inoculations from each of two wild-type baculoviruses,Autographa californica multiple nucleopolyhedrovirus(AcMNPV)and Helicoverpa zea single nucleopolyhedrovirus(HzSNPV),in their common host *** *** is a semi-permissive host of AcMNPV and fully permissive to HzSNPV,we hypothesized there are differential immune responses and fitness costs associated with resisting infection by each virus *** molted 4th-instar larvae that were inoculated with a low dose(LD15)of either virus showed signify icantly higher hemolymph FAD-glucose dehydrogenase(GLD)activities compared to the corresponding control *** phenoloxidase(PO)activity,protein concentration and total hemocyte numbers were not increased,but instead were lower than in control larvae at some time points *** that survived either virus inoculation exhibited reduced pupal weight;survivors inoculated with AcMNPV grew slower than the control larvae,while survivors of HzSNPV pupated earlier than control *** results highlight the complexity of immune responses and fitness costs associated with combating different baculoviruses.

关键词： ecological immunology FAD-glucose dehydrogenase hemocytes hostpathogen interactions nucleopolyhedrovirus phenoloxidase