Resistance monitoring and cross-resistance patterns of three rice planthoppers, Nilaparvata lugens, Sogatella furcifera and Laodelphax striatellus to dinotefuran in China.

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Mu, Xi-Chao; Zhang, Wei; Wang, Li-Xiang; Zhang, Shuai; Zhang, Kai; Gao, Cong-Fen; Wu, Shun-Fan

2016-11-01

Three rice planthoppers, brown planthopper, Nilaparvata lugens, white-backed planthopper, Sogatella furcifera and small brown planthopper, Laodelphax striatellus, are important pests of cultivated rice in tropical and temperate Asia. They have caused severe economic loss and developed resistance to insecticides from most chemical classes. Dinotefuran is the third neonicotinoid which possesses a broad spectrum and systemic insecticidal activity. We determined the susceptibility of dinotefuran to field populations from major rice production areas in China from 2013 to 2015. All the populations of S. furcifera and L. striatellus were kept susceptible to dinotefuran (0.7 to 1.4-fold of S. furcifera and 1.1-to 3.4-fold of L. striatellus) However, most strains of N. lugens (except FQ15) collected in 2015 had developed moderate resistance to dinotefuran, with resistance ratios (RR) ranging from 23.1 to 100.0 folds. Cross-resistance studies showed that chlorpyrifos-resistant and buprofezin-resistant Sogatella furcifera, chlorpyrifos-resistant and fipronil-resistant L. striatellus, imidacloprid-resistant and buprofezin-resistant Nilaparvata lugens exhibited negligible or no cross-resistance to dinotefuran. Synergism tests showed that piperonyl butoxide (PBO) produced a high synergism of dinotefuran effects in the DY15 and JS15 populations (2.14 and 2.52-fold, respectively). The obvious increase in resistance to dinotefuran in N. lugens indicates that insecticide resistance management strategies are urgently needed to prevent or delay further increase of insecticide resistance in N. lugens. Copyright © 2016 Elsevier B.V. All rights reserved.

Use of P-32 for determining varietal resistance of rice to brown planthopper (Nilaparvata lugens stal)

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Kuswadi, A.N. (National Atomic Energy Agency, Jakarta (Indonesia). Pasar Djumat Research Centre)

1981-07-01

The resistance was assessed based on the feeding activities of the insect on 15-day old seedling of six test varieties namely TN 1, Asahan, Brantas, Citarum, Serayu and Mudgo. A level of 175 ..mu..Ci per seedling appeared to give sufficiently high absorption of radiophosphorus by the brown planthoppers. The level of radioactivity in the brown planthopper fed for 24 hours on labelled rice plants appeared to be correlated with the susceptibility of the rice plant to brown planthopper. The radioactivity in the honeydew of those hoppers was less correlated with the rice susceptibility. The promising resistance screening method using P-32 tracer is thus more reliable when the radioactivity is detected in the insect rather than in the honeydew.

Transferrin Family Genes in the Brown Planthopper, Nilaparvata lugens (Hemiptera: Delphacidae) in Response to Three Insecticides.

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Wu, Shun-Fan; Li, Jian; Zhang, Yong; Gao, Cong-Fen

2018-02-09

Transferrins are involved in iron metabolism, immunity, xenobiotics tolerance, and development in eukaryotic organisms including insects. However, little is known about the relationship between transferrins and insecticide toxicology and resistance. Three transferrin family genes, NlTsf1, NlTsf2, and NlTsf3, of the brown planthopper, Nilaparvata lugens (Stål) (Hemiptera: Delphacidae)a major insect pest of rice field in Asia, had been identified and characterized in this study. Quantitative polymerase chain reaction results demonstrated that NlTsf1 was significantly higher than the other two genes in different tissues. All of them were expressed at higher levels in abdomen and head than in antenna, leg, stylet, and thorax. Compared with the control, the expression of three N. lugens transferrin family genes decreased dramatically 24 h after treatment with buprofezin, pymetrozine and imidacloprid. Published by Oxford University Press on behalf of Entomological Society of America 2017. This work is written by (a) US Government employee(s) and is in the public domain in the US.

Multi-generational effects of rice harboring Bph15 on brown planthopper, Nilaparvata lugens.

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Li, Jie; Shang, Keke; Liu, Jia; Jiang, Tingru; Hu, Dingbang; Hua, Hongxia

2014-02-01

The brown planthopper (BPH), Nilaparvata lugens, is one of the most devastating rice pests in Asia. Resistant cultivars are an effective way of managing BPH. Bph15 is a BPH resistance gene and has been introgressed into rice variety Minghui 63 (MH63). The multi-generational effects of rice line MH63::15 (harboring Bph15) on BPH were investigated and compared with its parental line MH63. U-test analysis indicated that, over seven generations, the developmental duration of BPH nymphs was significantly prolonged by MH63::15. The results of a two-way analysis indicated that, over seven generations, MH63::15 had significant negative effects on the hatchability, emergence rate, copulation rate, weight of adults and fecundity of BPH, but no significant effects on the survival rate of nymphs or female ratio of BPH. In addition, the development of ovary was significantly retarded by MH63::15, and the expression of oogenesis genes were either down-regulated (three genes) or up-regulated (one genes) by MH63::15 compared with MH63. After being reared continuously on MH63::15 for seven generations, most of the life parameters of BPH were negatively affected by MH63::15, especially fecundity and ovary development. These results indicate that MH63::15 rice has potential for use in the control of BPH. © 2013 Society of Chemical Industry.

Glutathione S-transferase of brown planthoppers (Nilaparvata lugens is essential for their adaptation to gramine-containing host plants.

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Xiao-Qin Sun

Full Text Available Plants have evolved complex processes to ward off attacks by insects. In parallel, insects have evolved mechanisms to thwart these plant defenses. To gain insight into mechanisms that mediate this arms race between plants and herbivorous insects, we investigated the interactions between gramine, a toxin synthesized by plants of the family Gramineae, and glutathione S transferase (GST, an enzyme found in insects that is known to detoxify xenobiotics. Here, we demonstrate that rice (Oryza sativa, a hydrophytic plant, also produces gramine and that rice resistance to brown planthoppers (Nilaparvata lugens, BPHs is highly associated with in planta gramine content. We also show that gramine is a toxicant that causes BPH mortality in vivo and that knockdown of BPH GST gene nlgst1-1 results in increased sensitivity to diets containing gramine. These results suggest that the knockdown of key detoxification genes in sap-sucking insects may provide an avenue for increasing their sensitivity to natural plant-associated defense mechanisms.

Glutathione S-transferase of brown planthoppers (Nilaparvata lugens) is essential for their adaptation to gramine-containing host plants.

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Sun, Xiao-Qin; Zhang, Mao-Xin; Yu, Jing-Ya; Jin, Yu; Ling, Bing; Du, Jin-Ping; Li, Gui-Hua; Qin, Qing-Ming; Cai, Qing-Nian

2013-01-01

Plants have evolved complex processes to ward off attacks by insects. In parallel, insects have evolved mechanisms to thwart these plant defenses. To gain insight into mechanisms that mediate this arms race between plants and herbivorous insects, we investigated the interactions between gramine, a toxin synthesized by plants of the family Gramineae, and glutathione S transferase (GST), an enzyme found in insects that is known to detoxify xenobiotics. Here, we demonstrate that rice (Oryza sativa), a hydrophytic plant, also produces gramine and that rice resistance to brown planthoppers (Nilaparvata lugens, BPHs) is highly associated with in planta gramine content. We also show that gramine is a toxicant that causes BPH mortality in vivo and that knockdown of BPH GST gene nlgst1-1 results in increased sensitivity to diets containing gramine. These results suggest that the knockdown of key detoxification genes in sap-sucking insects may provide an avenue for increasing their sensitivity to natural plant-associated defense mechanisms.

The use of P-32 for determining varietal resistance of rice to brown planthopper (Nilaparvata lugens stal)

International Nuclear Information System (INIS)

Kuswadi, Achmad Nasroh

1981-01-01

The resistance was assessed uased on the feeding activities of the insect on 15-day old seedling of six test varietes namely TN 1, Asahan, Brantas, Citarum, Serayu and Mudgo. A level of 175 μCi per seedling appeared to give sufficiently high absorption of radiophosphorus by the brown planthoppers. The level of radioactivity in the brown planthopper fed for 24 hours on labelled rice plants appeared to be correlated with the susceptibility of the rice plant to brown planthopper. The radioactivity in the honeydew of those hoppers was less correlated with the rice susceptibility. The promising resistance screening method using P-32 tracer is thus more reliable when the radioactivity is detected in the insect rather than in the honeydew. (author)

The effect of gamma radiation on sterility and mating ability of brown planthopper, Nilaparvata lugens(Stål) in field cage

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Limohpasmanee, W.; Kongratarpon, T.; Tannarin, T.

2017-06-01

The brown planthopper, Nilaparvata lugens(Stål) is the major rice pest in Thailand. Adults and nymphs suck the sap from the rice plant causing it to wilt and transmitting the grassy stunt and the ragged stunt diseases. The population suppression by the sterile insect technique is overwhelmingly a function of mating between sterile males and wild females. The objectives of these experiments were to determine the suitable dose which induces partially sterile in N. lugens and their effect on wild population in the field cages. One-day-old 4th and 5th instar nymphs and adults were irradiated in a 60Co irradiator at the doses of 30, 60, 90 and 120 Gy. It was found that irradiation at the dose of 90 Gy induced complete sterility in female and 78.47 % sterility in males. The inherited sterility were transferred to their progenies and induced 51.46 and 77.00 % sterility in F-1 males and females. The irradiation as the mention dose did not affect mating ability. The competitiveness index was increased when the ratio of irradiated males per normal male was increased. The releasing irradiated males at 10 fold of normal males in field cages could suppress F-1 population 80.11 % and suppress F-2 population 80.32 % when compare with the control. This technique may be applied to delay and/or reduce seasonal increase of brown planthopper.

Risk assessment of insecticides used in rice on miridbug, Cyrtorhinus lividipennis Reuter, the important predator of brown planthopper, Nilaparvata lugens (Stal.).

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Preetha, G; Stanley, J; Suresh, S; Samiyappan, R

2010-07-01

The green miridbug, Cyrtorhinus lividipennis, an important natural enemy of the rice brown planthopper (BPH), Nilaparvata lugens plays a major role as a predator in suppressing the pest population. The study assessed the impact of certain potential insecticides used in the rice ecosystem on the miridbug predator and brown planthopper through contact toxicity. Eleven insecticides, including neonicotinoids, diamides, azomethine pyridines, carbamates, pyrethroids, organophosphates and cyclodienes were selected to test their toxicities against the nymphs of C. lividipennis and N. lugens. Median lethal concentration (LC(50)) was determined for each insecticide using an insecticide-coated vial (scintillation) residue bioassay, which revealed BPMC as the highly toxic chemical with an LC(50) of 0.003mga.iL(-1) followed by ethofenprox and clothianidin with LC(50) of 0.006mga.iL(-1) at 48 HAT against C. lividipennis and ethofenprox as the highly toxic chemical with an LC(50) of 0.009mga.iL(-1) followed by clothianidin with an LC(50) of 0.211mga.iL(-1) at 48h after treatment (HAT) against N. lugens. Among the insecticides tested, the cyclodiene compound, endosulfan had the lowest acute contact toxicity (LC(50)=66.65mga.iL(-1) at 48 HAT) to C. lividipennis. Among the insecticides tested, endosulfan, chlorpyriphos, acephate and methyl parathion are regarded as safer to C. lividipennis based on selectivity ratio, hazard quotient and probit substitution method of risk assessments. 2010 Elsevier Ltd. All rights reserved.

Cycle affects imidacloprid efficiency by mediating cytochrome P450 expression in the brown planthopper Nilaparvata lugens.

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Kang, K; Yang, P; Pang, R; Yue, L; Zhang, W

2017-10-01

Circadian clocks influence most behaviours and physiological activities in animals, including daily fluctuations in metabolism. However, how the clock gene cycle influences insects' responses to pesticides has rarely been reported. Here, we provide evidence that cycle affects imidacloprid efficacy by mediating the expression of cytochrome P450 genes in the brown planthopper (BPH) Nilaparvata lugens, a serious insect pest of rice. Survival bioassays showed that the susceptibility of BPH adults to imidacloprid differed significantly between the two time points tested [Zeitgeber Time 8 (ZT8) and ZT4]. After cloning the cycle gene in the BPH (Nlcycle), we found that Nlcycle was expressed at higher levels in the fat body and midgut, and its expression was rhythmic with two peaks. Knockdown of Nlcycle affected the expression levels and rhythms of cytochrome P450 genes as well as susceptibility to imidacloprid. The survival rates of BPH adults after treatment with imidacloprid did not significantly differ between ZT4 and ZT8 after double-stranded Nlcycle treatment. These findings can be used to improve pesticide use and increase pesticide efficiency in the field. © 2017 The Royal Entomological Society.

Influence of rice black streaked dwarf virus on the ecological fitness of non-vector planthopper Nilaparvata lugens (Hemiptera: Delphacidae).

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Xu, Hong-Xing; He, Xiao-Chan; Zheng, Xu-Song; Yang, Ya-Jun; Lu, Zhong-Xian

2014-08-01

Rice black streak dwarf virus (RBSDV) is transmitted by the small brown planthopper (SBPH), Laodelphax striatellus (Fallen). Non-vector rice brown planthopper (BPH), Nilaparvata lugens (Stål), shares the same host rice plants with SBPH in paddy fields. The changes in nutritional composition of rice plants infected by RBSDV and the ecological fitness of BPH feeding on the infected plants were studied under both artificial climate chamber and field conditions. Contents of 16 detected amino acids and soluble sugar in RBSDV infected rice plants were higher than those in the healthy ones. On the diseased plants BPH had significantly higher nymphal survival rates, nymphal duration of the males, weight of the female adults, as well as egg hatchability compared to BPH being fed on healthy plants. However, there was no obvious difference in female nymph duration, longevity and fecundity. Defense enzymes (superoxidase dismutase, SOD and catalase, CAT) and detoxifying enzymes (carboxylesterase, CAE and glutathione S-transferase, GST) in BPH adults fed on diseased plants had markedly higher activities. The results indicate rice plants infected by RBSDV improved the ecological fitness of the brown planthopper, a serious pest but not a transmitter of the RBSDV virus. © 2013 Institute of Zoology, Chinese Academy of Sciences.

Resistance and tolerance to the brown planthopper, Nilaparvata lugens (Stål), in rice infested at different growth stages across a gradient of nitrogen applications.

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Horgan, Finbarr G; Peñalver Cruz, Ainara; Bernal, Carmencita C; Ramal, Angelee Fame; Almazan, Maria Liberty P; Wilby, Andrew

2018-03-01

High resource availability can reduce anti-herbivore resistance (a plant's ability to defend against herbivores and reduce damage) in rice, Oryza sativa L, but may also increase tolerance (a plant's ability to withstand damage by, for example, compensatory growth). Through a series of greenhouse, screenhouse and field experiments, this study examines fitness (survival and development × reproduction) of the brown planthopper, Nilaparvata lugens (Stål), on resistant (IR62) and susceptible (IR22) rice varieties and age-related rice tolerance to planthopper damage under varying resource (nitrogenous fertilizer) availability. Planthoppers reared on IR62 in the greenhouse had lower fitness than planthoppers on IR22. IR62 became increasingly resistant as plants aged. IR22 was generally more tolerant of planthopper damage, and tolerance increased in IR22, but declined in IR62, as the plants aged. Rice plants infested at pre-tillering stages (3-4 leaf stage) in the screenhouse had greater losses to root, shoot and grain yield per unit weight of planthopper than plants infested at tillering stages, particularly in IR22. These trends were mainly due to the impact of planthoppers during pre-tillering stages and the length of exposure to the planthoppers. High nitrogen compromised IR62 resistance, particularly in tillering plants in the greenhouse study; however, high nitrogen did not increase planthopper biomass-density on IR62 in greenhouse or field cages. Tolerance to damage in IR62 at mid-tillering stages declined under increasing levels of nitrogen, but nitrogen increased tolerance during late-tillering stages. Planthopper damage to IR22 in field cages was severe and hopperburn (plant death) occurred in 83% of IR22 plants under high nitrogen (60-150 kg N ha -1 ). In contrast, despite planthopper infestations, damage to IR62 was low in field-grown plants and productivity (tillers, roots, shoots and grain) increased in IR62 under increasing nitrogen. Our results

Identification of a sugar gustatory receptor and its effect on fecundity of the brown planthopper Nilaparvata lugens.

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Chen, Wei-Wen; Kang, Kui; Yang, Pan; Zhang, Wen-Qing

2017-11-27

In insects, the gustatory system plays a crucial role in multiple physiological behaviors, including feeding, toxin avoidance, courtship, mating and oviposition. Gustatory stimuli from the environment are recognized by gustatory receptors. To date, little is known about the function of gustatory receptors in agricultural pest insects. In this study, we cloned a sugar gustatory receptor gene, NlGr11, from the brown planthopper (BPH), Nilaparvata lugens (Stål), a serious pest of rice in Asia; we then identified its ligands, namely, fructose, galactose and arabinose, by calcium imaging assay. After injection of NlGr11 double-stranded RNA, we found that the number of eggs laid by BPH decreased. Moreover, we found that NlGr11 inhibited the phosphorylation of adenosine monophosphate-activated protein kinase (AMPK) and promoted the phosphorylation of protein kinase B (AKT). These findings demonstrated that NlGr11 could accelerate the fecundity of BPH through AMPK- and AKT-mediated signaling pathways. This is the first report to indicate that a gustatory receptor modulates the fecundity of insects and that the receptor could be a potential target for pest control. © 2017 Institute of Zoology, Chinese Academy of Sciences.

Silencing OsSLR1 enhances the resistance of rice to the brown planthopper Nilaparvata lugens.

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Zhang, Jin; Luo, Ting; Wang, Wanwan; Cao, Tiantian; Li, Ran; Lou, Yonggen

2017-10-01

DELLA proteins, negative regulators of the gibberellin (GA) pathway, play important roles in plant growth, development and pathogen resistance by regulating multiple phytohormone signals. Yet, whether and how they regulate plant herbivore resistance remain unknown. We found that the expression of the rice DELLA gene OsSLR1 was down-regulated by an infestation of female adults of the brown planthopper (BPH) Nilaparvata lugens. On one hand, OsSLR1 positively regulated BPH-induced levels of two mitogen-activated protein kinase and four WRKY transcripts, and of jasmonic acid, ethylene and H 2 O 2 . On the other hand, silencing OsSLR1 enhanced constitutive levels of defence-related compounds, phenolic acids, lignin and cellulose, as well as the resistance of rice to BPH in the laboratory and in the field. The increased resistance in rice with silencing of OsSLR1 is probably due to impaired JA and ethylene pathways, and, at least in part, to the increased lignin level and mechanical hardness of rice leaf sheaths. Our findings illustrate that OsSLR1, acting as an early negative regulator, plays an important role in regulating the resistance of rice to BPH by activating appropriate defence-related signalling pathways and compounds. Moreover, our data also provide new insights into relationships between plant growth and defence. © 2017 John Wiley & Sons Ltd.

Susceptibility to neonicotinoids and risk of resistance development in the brown planthopper, Nilaparvata lugens (Stål) (Homoptera: Delphacidae).

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Wang, Yanhua; Chen, Jin; Zhu, Yu Cheng; Ma, Chongyong; Huang, Yue; Shen, Jinliang

2008-12-01

In recent years, outbreaks of the brown planthopper, Nilaparvata lugens (Stål), have occurred more frequently in China. The objective of this study was to determine the susceptibility of N. lugens to neonicotinoids and other insecticides in major rice production areas in China. Results indicated that substantial variations in the susceptibility to different insecticides existed in N. lugens. Field populations had developed variable resistance levels to neonicotinoids, with a high resistance level to imidacloprid (RR: 135.3-301.3-fold), a medium resistance level to imidaclothiz (RR: 35-41.2-fold), a low resistance level to thiamethoxam (up to 9.9-fold) and no resistance to dinotefuran, nitenpyram and thiacloprid (RR buprofezin. In addition, N. lugens had been able to develop 1424-fold resistance to imidacloprid in the laboratory after the insect was selected with imidacloprid for 26 generations. Long-term use of imidacloprid in a wide range of rice-growing areas might be associated with high levels of resistance in N. lugens. Therefore, insecticide resistance management strategies must be developed to prevent further increase in resistance.

Brown planthopper Nilaparvata lugens was concentrated at the rear of the typhoon Soudelor in Eastern China in August 2015.

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Ma, Jian; Wang, Ye-Chen; Hu, Yan-Yue; Lu, Ming-Hong; Wan, Gui-Jun; Chen, Fa-Jun; Liu, Wan-Cai; Zhai, Bao-Ping; Hu, Gao

2017-03-28

Sometimes, extreme weather is vital for the population survival of migratory insects by causing sudden population collapse or outbreak. Several studies have shown that rice planthopper migration was significantly influenced by typhoons in eastern Asia. Most typhoons occur in the summer, especially in August. In August, brown planthopper Nilaparvata lugens (Stål) migrates northward or southward depending on wind direction, and thus typhoons can potentially influence its migration process and population distribution. However, this has not yet been studied. This paper reported a case study on the effects of Typhoon Soudelor on the summer migration of N. lugens in eastern China in 2015. The migration pathways of N. lugens were reconstructed for the period under the influence of a typhoon by calculating the trajectories and migration events in eight counties of the Yangtze River Valley region with ancillary information. Trajectory modelling showed that most migrants took short distance migrations (less than 200 km) under the influence of the Typhoon Soudelor. Numerous N. lugens migrants were concentrated and deposited at the rear of the typhoon during the last 5 days of Typhoon Soudelor on August 9-13 due to horizontal convergence, and this led to an outbreak population. These results indicated that the N. lugens population was redistributed by the typhoon in the summer and that the population dynamics at the rear of a typhoon should be kept under close surveillance. This study provided insight into migratory organisms adapting to atmospheric features. © 2017 Institute of Zoology, Chinese Academy of Sciences.

Identification of differentially expressed genes in brown planthopper Nilaparvata lugens (Hemiptera: Delphacidae) responding to host plant resistance.

Science.gov (United States)

Yang, Zhifan; Zhang, Futie; Zhu, Lili; He, Guangcun

2006-02-01

The brown planthopper Nilaparvata lugens Stål is one of the major insect pests of rice Oryza sativa L. The host resistance exhibits profound effects on growth, development and propagation of N. lugens. To investigate the molecular response of N. lugens to host resistance, a cDNA-amplified fragment length polymorphism (cDNA-AFLP) technique was employed to identify the differentially expressed genes in the nymphs feeding on three rice varieties. Of the 2,800 cDNA bands analysed, 54 were up-regulated and seven down-regulated qualitatively in N. lugens when the ingestion sources were changed from susceptible rice plants to resistant ones. Sequence analysis of the differential transcript-derived fragments showed that the genes involved in signalling, stress response, gene expression regulation, detoxification and metabolism were regulated by host resistance. Four of the transcript-derived fragments corresponding to genes encoding for a putative B subunit of phosphatase PP2A, a nemo kinase, a cytochrome P450 monooxygenase and a prolyl endopeptidase were further characterized in detail. Northern blot analysis confirmed that the expression of the four genes was enhanced in N. lugens feeding on resistant rice plants. The roles of these genes in the defensive response of N. lugens to host plant resistance were discussed.

Inheritance mode and realized heritability of resistance to imidacloprid in the brown planthopper, Nilaparvata lugens (Stål) (Homoptera: Delphacidae).

Science.gov (United States)

Wang, Yan Hua; Liu, Xu Gan; Zhu, Yu Cheng; Wu, Sheng Gan; Li, Shu Yong; Chen, Wen Ming; Shen, Jin Liang

2009-06-01

The brown planthopper, Nilaparvata lugens (Stål), is a serious pest that causes enormous losses to the rice crop in Asia. The genetic basis of imidacloprid resistance was investigated in N. lugens. The resistant strain, selected for imidacloprid resistance from a field population of N. lugens collected from Nanjing, Jiangsu Province, China, showed a 964-fold resistance compared with the laboratory strain. Progenies of reciprocal crosses (F(1) and F(1)') showed similar dose-mortality responses (LC(50)) to imidacloprid, and also exhibited a similar degree of dominance (D), 0.58 for F(1) and 0.63 for F(1)'. Chi-square analyses of self-bred and backcross progenies (F(2), F(2)' and BC respectively) rejected the hypothesis for a single gene control of the resistance. The estimated realized heritability (h(2)) of imidacloprid resistance was 0.1141 in the resistant strain of N. lugens. The results showed that imidacloprid resistance in N. lugens was autosomal and was expressed as an incompletely dominant trait, probably controlled by multiple genes.

Predation of Five Generalist Predators on Brown Planthopper (Nilaparvata lugens Stål

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Sri Karindah

2015-09-01

Full Text Available Two generalist predators of brown planthopper,Metioche vittaticollis and Anaxipha longipennis (Gryllidae have not been much studied in Indonesia. This research was conducted to study and compare the predatory ability of M. vittaticollis, A. longipennis (Gryllidae and three coleopterans, Paederus fuscipes (Staphylinidae, Ophionea sp. (Carabidae,and Micraspis sp. (Coccinellidae against brown planthopper (fourth and fifth instars under laboratory condition. In total, 20 nymphs of N. lugens were exposed for 2 hour to each predator for 5 consecutive days. Prey consumptions by the predatory crickets, M. vittaticollis and A. longipennis were greater than the other predators and followed by A. longipennis, Micraspis sp., P. fuscipes, and Ophionea sp. respectively. Consumption rates of M. vittaticolis and A. longipenis were also higher than other predators. Micraspis sp was more active on predation in the morning,while M. vittaticollis, A. longipennis, P. fuscipes, and Ophionea sp. were more active both in the morning and the night but not in the afternoon. However, all five species of predators were not so active in preying during the afternoon. In conclusion, a major effort should be extended to conserve these predatory crickets especially M. vittaticollis and A. longipennis.

Biological effects of rice harbouring Bph14 and Bph15 on brown planthopper, Nilaparvata lugens.

Science.gov (United States)

Li, Jie; Chen, Qiuhong; Wang, Liangquan; Liu, Jia; Shang, Keke; Hua, Hongxia

2011-05-01

Brown planthopper (Nilaparvata lugens Stål; BPH) resistance genes Bph14 and Bph15 have been introgressed singly or pyramided into rice variety Minghui 63 (MH63). The antibiosis and antixenosis effects of these rice lines on BPH and the expression of five P450 genes of BPH regulated by these rice lines were investigated in this study. The resistance level of rice lines harbouring resistance genes was improved compared with MH63. MH63::14 (carrying Bph14) had negative effects on the development of males, honeydew excretion of females, the female ratio and the copulation rate compared with MH63. MH63::14 also exhibited antixenosis action against BPH nymphs, female adults and oviposition. Besides these negative effects, MH63::15 (carrying Bph15) could also retard the development of females, lower the fecundity and shorten the lifespan of females. The antixenosis action of MH63::15 was stronger than that of MH63::14. When Bph14 and Bph15 were pyramided, antibiosis and antixenosis effects were significantly enhanced relative to single-introgression lines. Among the five P450 genes of BPH, expression of three genes was upregulated, one gene was downregulated and one gene was unchanged by resistant hosts. Both Bph14 and Bph15 could improve resistance levels of MH63. MH63::15 and MH63::14&15 had greater potential to control BPH infestations than MH63::14. Copyright © 2011 Society of Chemical Industry.

Outbreaks of the brown planthopper Nilaparvata lugens (Stål) in the Yangtze River Delta: immigration or local reproduction?

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Hu, Gao; Lu, Fang; Zhai, Bao-Ping; Lu, Ming-Hong; Liu, Wan-Cai; Zhu, Feng; Wu, Xiang-Wen; Chen, Gui-Hua; Zhang, Xiao-Xi

2014-01-01

An effective control strategy for migratory pests is difficult to implement because the cause of infestation (i.e., immigration or local reproduction) is often not established. In particular, the outbreak mechanisms of the brown planthopper, Nilaparvata lugens (Stål), an insect causing massive losses in rice fields in the Yangtze River Delta in China, are frequently unclear. Field surveys of N. lugens were performed in Jiangsu and Zhejiang Provinces in 2008 to 2010 and related historical data from 2003 onwards were collected and analyzed to clarify the cause of these infestations. Results showed that outbreaks of N. lugens in the Yangtze River Delta were mostly associated with an extremely high increase in population. Thus, reproduction rather than immigration from distant sources were the cause of the infestations. Although mass migration occurred late in the season (late August and early September), the source areas of N. lugens catches in the Yangtze River Delta were mainly located in nearby areas, including the Yangtze River Delta itself, Anhui and northern Jiangxi Provinces. These regions collectively form the lower-middle reaches of the Yangtze River, and the late migration can thus be considered as an internal bioflow within one population.

Outbreaks of the Brown Planthopper Nilaparvata lugens (Stål) in the Yangtze River Delta: Immigration or Local Reproduction?

Science.gov (United States)

Zhai, Bao-Ping; Lu, Ming-Hong; Liu, Wan-Cai; Zhu, Feng; Wu, Xiang-Wen; Chen, Gui-Hua; Zhang, Xiao-Xi

2014-01-01

An effective control strategy for migratory pests is difficult to implement because the cause of infestation (i.e., immigration or local reproduction) is often not established. In particular, the outbreak mechanisms of the brown planthopper, Nilaparvata lugens (Stål), an insect causing massive losses in rice fields in the Yangtze River Delta in China, are frequently unclear. Field surveys of N. lugens were performed in Jiangsu and Zhejiang Provinces in 2008 to 2010 and related historical data from 2003 onwards were collected and analyzed to clarify the cause of these infestations. Results showed that outbreaks of N. lugens in the Yangtze River Delta were mostly associated with an extremely high increase in population. Thus, reproduction rather than immigration from distant sources were the cause of the infestations. Although mass migration occurred late in the season (late August and early September), the source areas of N. lugens catches in the Yangtze River Delta were mainly located in nearby areas, including the Yangtze River Delta itself, Anhui and northern Jiangxi Provinces. These regions collectively form the lower-middle reaches of the Yangtze River, and the late migration can thus be considered as an internal bioflow within one population. PMID:24558459

The identification of candidate rice genes that confer resistance to the brown planthopper (Nilaparvata lugens) through representational difference analysis.

Science.gov (United States)

Park, Dong-Soo; Lee, Sang-Kyu; Lee, Jong-Hee; Song, Min-Young; Song, Song-Yi; Kwak, Do-Yeon; Yeo, Un-Sang; Jeon, Nam-Soo; Park, Soo-Kwon; Yi, Gihwan; Song, You-Chun; Nam, Min-Hee; Ku, Yeon-Chung; Jeon, Jong-Seong

2007-08-01

The development of rice varieties (Oryza sativa L.) that are resistant to the brown planthopper (BPH; Nilaparvata lugens Stål) is an important objective in current breeding programs. In this study, we generated 132 BC(5)F(5) near-isogenic rice lines (NILs) by five backcrosses of Samgangbyeo, a BPH resistant indica variety carrying the Bph1 locus, with Nagdongbyeo, a BPH susceptible japonica variety. To identify genes that confer BPH resistance, we employed representational difference analysis (RDA) to detect transcripts that were exclusively expressed in one of our BPH resistant NIL, SNBC61, during insect feeding. The chromosomal mapping of the RDA clones that we subsequently isolated revealed that they are located in close proximity either to known quantitative trait loci or to an introgressed SSR marker from the BPH resistant donor parent Samgangbyeo. Genomic DNA gel-blot analysis further revealed that loci of all RDA clones in SNBC61 correspond to the alleles of Samgangbyeo. Most of the RDA clones were found to be exclusively expressed in SNBC61 and could be assigned to functional groups involved in plant defense. These RDA clones therefore represent candidate defense genes for BPH resistance.

The Transcription Factor OsWRKY45 Negatively Modulates the Resistance of Rice to the Brown Planthopper Nilaparvata lugens.

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Huangfu, Jiayi; Li, Jiancai; Li, Ran; Ye, Meng; Kuai, Peng; Zhang, Tongfang; Lou, Yonggen

2016-05-31

WRKY transcription factors play a central role not only in plant growth and development but also in plant stress responses. However, the role of WRKY transcription factors in herbivore-induced plant defenses and their underlying mechanisms, especially in rice, remains largely unclear. Here, we cloned a rice WRKY gene OsWRKY45, whose expression was induced by mechanical wounding, by infestation of the brown planthopper (BPH, Nilaparvata lugens) and by treatment with jasmonic acid (JA) or salicylic acid (SA). The antisense expression of OsWRKY45 (as-wrky) enhanced BPH-induced levels of H₂O₂ and ethylene, reduced feeding and oviposition preference as well as the survival rate of BPH, and delayed the development of BPH nymphs. Consistently, lower population densities of BPH on as-wrky lines, compared to those on wild-type (WT) plants, were observed in field experiments. On the other hand, as-wrky lines in the field had lower susceptibility to sheath blight (caused by Rhizoctonia solani) but higher susceptibility to rice blast (caused by Magnaporthe oryzae) than did WT plants. These findings suggest that OsWRKY45 plays important but contrasting roles in regulating the resistance of rice to pathogens and herbivores, and attention should be paid if OsWRKY45 is used to develop disease or herbivore-resistant rice.

Screening of IR50 x Rathu Heenati F7 RILs and identification of SSR markers linked to brown planthopper (Nilaparvata lugens Stål) resistance in rice (Oryza sativa L.).

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Kumari, Sanju; M Sheba, Jennifer; Marappan, Maheshwaran; Ponnuswamy, Shanmugasunderam; Seetharaman, Suresh; Pothi, Nagarajan; Subbarayalu, Mohankumar; Muthurajan, Raveendran; Natesan, Senthil

2010-09-01

Brown planthopper (Nilaparvata lugens Stål) is one of the major insect pests of rice. A Sri Lankan indica rice cultivar Rathu Heenati was found to be resistant to all biotypes of the brown planthopper. In the present study, a total of 268 F(7) RILs of IR50 and Rathu Heenati were phenotyped for their level of resistance against BPH by the standard seedbox screening test (SSST) in the greenhouse. A total of 53 SSR primers mapped on the chromosome 3 were used to screen the polymorphism between the parents IR50 and Rathu Heenati, out of which eleven were found to be polymorphic between IR50 and Rathu Heenati. The eleven primers that have shown polymorphism between the IR50 and Rathu Heenati parents were genotyped in a set of five resistant RILs and five susceptible RILs along with the parents for co-segregation analysis. Among the eleven primers, two primers namely RM3180 (18.22 Mb) and RM2453 (20.19 Mb) showed complete co-segregation with resistance. The identification of SSR markers linked with BPH resistant could be used for the maker assisted selection (MAS) program in rice breeding and to map the resistant genes on rice chromosomes for further gene cloning.

Proteomic and transcriptomic analyses of fecundity in the brown planthopper Nilaparvata lugens (Stål).

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Zhai, Yifan; Zhang, Jianqing; Sun, Zhongxiang; Dong, Xiaolin; He, Yuan; Kang, Kui; Liu, Zhichao; Zhang, Wenqing

2013-11-01

As an r-strategy insect species, the brown planthopper (BPH) Nilaparvata lugens (Stål) is a serious pest of rice crops in the temperate and tropical regions of Asia and Australia, which may be due to its robust fecundity. Here we combined 2-DE comparative proteomic and RNA-seq transcriptomic analyses to identify fecundity-related proteins and genes. Using high- and low-fecundity populations as sample groups, a total of 54 and 75 proteins were significantly altered in the third and sixth day brachypterous female stages, respectively, and 39 and 54 of these proteins were identified by MALDI-TOF/TOF MS. In addition, 71,966 unigenes were quantified by Illumina sequencing. On the basis of the transcriptomic analysis, 7408 and 1639 unigenes demonstrated higher expression levels in the high-fecundity population in the second day brachypterous female adults and the second day fifth instar nymphs, respectively, and 411 unigenes were up-regulated in both groups. Of these dozens of proteins and thousands of unigenes, five were differentially expressed at both the protein and mRNA levels at all four time points, suggesting that these genes may regulate fecundity. Glutamine synthetase (GS) was chosen for further functional studies. RNAi knockdown of the GS gene reduced the fecundity of N. lugens by 64.6%, disrupted ovary development, and inhibited vitellogenin (Vg) expression. Our results show that a combination of proteomic and transcriptomic analyses provided five candidate proteins and genes for further study. The knowledge gained from this study may lead to a more fundamental understanding of the fecundity of this important agricultural insect pest.

Genomic and transcriptomic insights into the cytochrome P450 monooxygenase gene repertoire in the rice pest brown planthopper, Nilaparvata lugens.

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Lao, Shu-Hua; Huang, Xiao-Hui; Huang, Hai-Jian; Liu, Cheng-Wen; Zhang, Chuan-Xi; Bao, Yan-Yuan

2015-11-01

The cytochrome P450 monooxygenase (P450) gene family is one of the most abundant eukaryotic gene families that encode detoxification enzymes. In this study, we identified an abundance of P450 gene repertoire through genome- and transcriptome-wide analysis in the brown planthopper (Nilaparvata lugens), the most destructive rice pest in Asia. Detailed gene information including the exon-intron organization, size, transcription orientation and distribution in the genome revealed that many P450 loci were closely situated on the same scaffold, indicating frequent occurrence of gene duplications. Insecticide-response expression profiling revealed that imidacloprid significantly increased NlCYP6CS1v2, NLCYP4CE1v2, NlCYP4DE1, NlCYP417A1v2 and NlCYP439A1 expression; while triazophos and deltamethrin notably enhanced NlCYP303A1 expression. Expression analysis at the developmental stage showed the egg-, nymph-, male- and female-specific expression patterns of N. lugens P450 genes. These novel findings will be helpful for clarifying the P450 functions in physiological processes including development, reproduction and insecticide resistance in this insect species. Copyright © 2015 Elsevier Inc. All rights reserved.

Decrease of insecticide resistance over generations without exposure to insecticides in Nilaparvata lugens (Hemipteran: Delphacidae).

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Yang, Yajun; Dong, Biqin; Xu, Hongxing; Zheng, Xusong; Tian, Junce; Heong, Kongleun; Lu, Zhongxian

2014-08-01

The brown planthopper, Nilaparvata lugens (Stål), is one of the most important insect pests on paddy rice in tropical and temperate Asia. Overuse and misuse of insecticides have resulted in the development of high resistance to many different insecticides in this pest. Studies were conducted to evaluate the change of resistance level to four insecticides over 15 generations without any exposure to insecticides in brown planthopper. After 15 generations' rearing without exposure to insecticide, brown planthopper could reverse the resistance to imidacloprid, chlorpyrifos, fipronil, and fenobucarb. The range and style of resistance reversal of brown planthopper differed when treated with four different insecticides. To monitor potential changes in insect physiological responses, we measured the activity of each of the three selected enzymes, including acetylcholinesterases (AChE), general esterases (EST), and glutathione S-transferases. After multiple generations' rearing without exposure to insecticide, AChE and EST activities of brown planthopper declined with the increased generations, suggesting that the brown planthopper population adjusted activities of EST and AChE to adapt to the non-insecticide environment. These findings suggest that the reducing, temporary stop, or rotation of insecticide application could be incorporated into the brown planthopper management.

Marker-assisted pyramiding of brown planthopper (Nilaparvata lugens Stål) resistance genes Bph1 and Bph2 on rice chromosome 12.

Science.gov (United States)

Sharma, Prem N; Torii, Akihide; Takumi, Shigeo; Mori, Naoki; Nakamura, Chiharu

2004-01-01

Brown planthopper (BPH) (Nilaparvata lugens Stål) is a significant insect pest of rice (Oryza sativa L.). We constructed a gene-pyramided japonica line, in which two BPH resistance genes Bph1 and Bph2 on the long arm of chromosome 12 independently derived from two indica resistance lines were combined through the recombinant selection. The gene-pyramiding was achieved based on the previously constructed high-resolution linkage maps of the two genes. Two co-dominant and four dominant PCR-based markers flanking the loci were used to select for a homozygous recombinant line in a segregating population that was derived from a cross between the parental homozygous single-gene introgression lines. BPH bioassay showed that the resistance level of the pyramided line was equivalent to that of the Bph1-single introgression line, which showed a higher level of resistance than the Bph2-single introgression line. The pyramid line should provide a useful experimental means for studying the fine structure of the chromosomal region covering these two major BPH resistance genes.

Insecticide resistance monitoring and correlation analysis of insecticides in field populations of the brown planthopper Nilaparvata lugens (stål) in China 2012-2014.

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Zhang, Xiaolei; Liao, Xun; Mao, Kaikai; Zhang, Kaixiong; Wan, Hu; Li, Jianhong

2016-09-01

The brown planthopper is a serious rice pest in China. Chemical insecticides have been considered a satisfactory means of controlling the brown planthopper. In the present study, we determined the susceptibility of twenty-one populations of Nilaparvata lugens to eleven insecticides by a rice-stem dipping method from 2012 to 2014 in eight provinces of China. These field-collected populations of N. lugens had developed high levels of resistance to imidacloprid (resistant ratio, RR=233.3-2029-fold) and buprofezin (RR=147.0-1222). Furthermore, N. lugens showed moderate to high levels of resistance to thiamethoxam (RR=25.9-159.2) and low to moderate levels of resistance to dinotefuran (RR=6.4-29.1), clothianidin (RR=6.1-33.6), ethiprole (RR=11.5-71.8), isoprocarb (RR=17.1-70.2), and chlorpyrifos (RR=7.4-30.7). In contrast, the susceptibility of N. lugens to etofenprox (RR=1.1-4.9), thiacloprid (RR=2.9-8.2) and acetamiprid (RR=2.7-26.2) remained susceptible to moderate levels of resistance. Significant correlations were detected between the LC50 values of imidacloprid and thiamethoxam, dinotefuran, buprofezin, and etofenprox, as well as between clothianidin and thiamethoxam, dinotefuran, ethiprole, acetamiprid, and thiacloprid. Similarly, significant correlations were observed between chlorpyrifos and etofenprox, acetamiprid and thiacloprid. Additionally, the activity of the detoxification enzymes of N. lugens showed a significant correlation with the log LC50 values of imidacloprid, dinotefuran and ethiprole. These results will be beneficial for effective insecticide resistance management strategies to prevent or delay the development of insecticide resistance. Copyright © 2015 Elsevier B.V. All rights reserved.

Genomics of interaction between the brown planthopper and rice.

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Jing, Shengli; Zhao, Yan; Du, Bo; Chen, Rongzhi; Zhu, Lili; He, Guangcun

2017-02-01

Rice (Oryza sativa L.) and the brown planthopper (Nilaparvata lugens (Stål)) form a model system for dissection of the mechanism of interaction between insect pest and crop. In this review, we focus on the genomics of BPH-rice interaction. On the side of rice, a number of BPH-resistance genes have been identified genetically. Thirteen of these genes have been cloned which shed a light on the molecular basis of the interaction. On the aspect of BPH, a lot of salivary proteins have been identified using transcriptome and proteome techniques. The genetic loci of virulence were mapped in BPH genome based on the linkage map. The understanding of interaction between BPH and rice will provide novel insights into efficient control of this pest. Copyright © 2017 The Authors. Published by Elsevier Inc. All rights reserved.

Geographic and research center origins of rice resistance to asian planthoppers and leafhoppers: implications for rice breeding and gene deployment

NARCIS (Netherlands)

Horgan, F.G.; Srinivasan, Thanga Suja; Bentur, Jagadish S.; Kumar, R.; Bhanu, K.V.; Singh Sarao, Preetinder; Chien, Ho Van; Almazan, M.L.P.; Bernal, Carmencita C.; Ramal, Angelee Fame; Ferrater, J.B.; Huang, Shou Horng

2017-01-01

This study examines aspects of virulence to resistant rice varieties among planthoppers and leafhoppers. Using a series of resistant varieties, brown planthopper, Nilaparvata lugens, virulence was assessed in seedlings and early-tillering plants at seven research centers in South and East Asia.

The Transcription Factor OsWRKY45 Negatively Modulates the Resistance of Rice to the Brown Planthopper Nilaparvata lugens

Science.gov (United States)

Huangfu, Jiayi; Li, Jiancai; Li, Ran; Ye, Meng; Kuai, Peng; Zhang, Tongfang; Lou, Yonggen

2016-01-01

WRKY transcription factors play a central role not only in plant growth and development but also in plant stress responses. However, the role of WRKY transcription factors in herbivore-induced plant defenses and their underlying mechanisms, especially in rice, remains largely unclear. Here, we cloned a rice WRKY gene OsWRKY45, whose expression was induced by mechanical wounding, by infestation of the brown planthopper (BPH, Nilaparvata lugens) and by treatment with jasmonic acid (JA) or salicylic acid (SA). The antisense expression of OsWRKY45 (as-wrky) enhanced BPH-induced levels of H2O2 and ethylene, reduced feeding and oviposition preference as well as the survival rate of BPH, and delayed the development of BPH nymphs. Consistently, lower population densities of BPH on as-wrky lines, compared to those on wild-type (WT) plants, were observed in field experiments. On the other hand, as-wrky lines in the field had lower susceptibility to sheath blight (caused by Rhizoctonia solani) but higher susceptibility to rice blast (caused by Magnaporthe oryzae) than did WT plants. These findings suggest that OsWRKY45 plays important but contrasting roles in regulating the resistance of rice to pathogens and herbivores, and attention should be paid if OsWRKY45 is used to develop disease or herbivore-resistant rice. PMID:27258255

The Transcription Factor OsWRKY45 Negatively Modulates the Resistance of Rice to the Brown Planthopper Nilaparvata lugens

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Jiayi Huangfu

2016-05-01

Full Text Available WRKY transcription factors play a central role not only in plant growth and development but also in plant stress responses. However, the role of WRKY transcription factors in herbivore-induced plant defenses and their underlying mechanisms, especially in rice, remains largely unclear. Here, we cloned a rice WRKY gene OsWRKY45, whose expression was induced by mechanical wounding, by infestation of the brown planthopper (BPH, Nilaparvata lugens and by treatment with jasmonic acid (JA or salicylic acid (SA. The antisense expression of OsWRKY45 (as-wrky enhanced BPH-induced levels of H2O2 and ethylene, reduced feeding and oviposition preference as well as the survival rate of BPH, and delayed the development of BPH nymphs. Consistently, lower population densities of BPH on as-wrky lines, compared to those on wild-type (WT plants, were observed in field experiments. On the other hand, as-wrky lines in the field had lower susceptibility to sheath blight (caused by Rhizoctonia solani but higher susceptibility to rice blast (caused by Magnaporthe oryzae than did WT plants. These findings suggest that OsWRKY45 plays important but contrasting roles in regulating the resistance of rice to pathogens and herbivores, and attention should be paid if OsWRKY45 is used to develop disease or herbivore-resistant rice.

Molecular mapping and genetic analysis of a rice brown planthopper (Nilaparvata lugens Stål) resistance gene.

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Yang, Haiyuan; Ren, Xiang; Weng, Qingmei; Zhu, Lili; He, Guangcun

2002-01-01

The brown planthopper (BPH), Nilaparvata lugens Stål, is a serious insect pest of rice (Oryza saliva L.). We have determined the chromosomal location of a BPH resistance gene in rice using SSR and RFLP techniques. A rice line 'B14', derived from the wild rice Oryza latifolia, showed high resistance to BPH. For tagging the resistance gene in 'B14X', an F2 population and a recombinant inbred (RI) population from a cross between Taichung Native 1 and 'B14' were developed and evaluated for BPH resistance. The results showed that a single dominant gene controlled the resistance of 'B14' to BPH. Bulked segregant SSR analysis was employed for identification of DNA markers linked to the resistance gene. From the survey of 302 SSR primer pairs, three SSR (RM335, RM261, RM185) markers linked to the resistance gene were identified. The closest SSR marker RM261 was linked to the resistance gene at a distance of 1.8 cM. Regions surrounding the resistance gene and the SSR markers were examined with additional RFLP markers on chromosome 4 to define the location of the resistance gene. Linkage of RFLP markers C820, R288, C946 with the resistance gene further confirmed its location on the short arm of chromosome 4. Closely linked DNA markers will facilitate selection for resistant lines in breeding programs and provide the basis for map-based cloning of this resistance gene.

Silencing a sugar transporter gene reduces growth and fecundity in the brown planthopper, Nilaparvata lugens (Stål) (Hemiptera: Delphacidae).

Science.gov (United States)

Ge, Lin-Quan; Jiang, Yi-Ping; Xia, Ting; Song, Qi-Sheng; Stanley, David; Kuai, Peng; Lu, Xiu-Li; Yang, Guo-Qing; Wu, Jin-Cai

2015-07-17

The brown planthopper (BPH), Nilaparvata lugens, sugar transporter gene 6 (Nlst6) is a facilitative glucose/fructose transporter (often called a passive carrier) expressed in midgut that mediates sugar transport from the midgut lumen to hemolymph. The influence of down regulating expression of sugar transporter genes on insect growth, development, and fecundity is unknown. Nonetheless, it is reasonable to suspect that transporter-mediated uptake of dietary sugar is essential to the biology of phloem-feeding insects. Based on this reasoning, we posed the hypothesis that silencing, or reducing expression, of a BPH sugar transporter gene would be deleterious to the insects. To test our hypothesis, we examined the effects of Nlst6 knockdown on BPH biology. Reducing expression of Nlst6 led to profound effects on BPHs. It significantly prolonged the pre-oviposition period, shortened the oviposition period, decreased the number of eggs deposited and reduced body weight, compared to controls. Nlst6 knockdown also significantly decreased fat body and ovarian (particularly vitellogenin) protein content as well as vitellogenin gene expression. Experimental BPHs accumulated less fat body glucose compared to controls. We infer that Nlst6 acts in BPH growth and fecundity, and has potential as a novel target gene for control of phloem-feeding pest insects.

Expression of BrD1, a plant defensin from Brassica rapa, confers resistance against brown planthopper (Nilaparvata lugens) in transgenic rices.

Science.gov (United States)

Choi, Man-Soo; Kim, Yul-Ho; Park, Hyang-Mi; Seo, Bo-Yoon; Jung, Jin-Kyo; Kim, Sun-Tae; Kim, Min-Chul; Shin, Dong-Bum; Yun, Hong-Tai; Choi, Im-Soo; Kim, Chung-Kon; Lee, Jang-Yong

2009-08-31

Plant defensins are small (5-10 kDa) basic peptides thought to be an important component of the defense pathway against fungal and/or bacterial pathogens. To understand the role of plant defensins in protecting plants against the brown planthopper, a type of insect herbivore, we isolated the Brassica rapa Defensin 1 (BrD1) gene and introduced it into rice (Oryza sativa L.) to produce stable transgenic plants. The BrD1 protein is homologous to other plant defensins and contains both an N-terminal endoplasmic reticulum signal sequence and a defensin domain, which are highly conserved in all plant defensins. Based on a phylogenetic analysis of the defensin domain of various plant defensins, we established that BrD1 belongs to a distinct subgroup of plant defensins. Relative to the wild type, transgenic rices expressing BrD1 exhibit strong resistance to brown planthopper nymphs and female adults. These results suggest that BrD1 exhibits insecticidal activity, and might be useful for developing cereal crop plants resistant to sap-sucking insects, such as the brown planthopper.

Molecular cloning and characterization of an acetylcholinesterase cDNA in the brown planthopper, Nilaparvata lugens.

Science.gov (United States)

Yang, Zhifan; Chen, Jun; Chen, Yongqin; Jiang, Sijing

2010-01-01

A full cDNA encoding an acetylcholinesterase (AChE, EC 3.1.1.7) was cloned and characterized from the brown planthopper, Nilaparvata lugens Stål (Hemiptera: Delphacidae). The complete cDNA (2467 bp) contains a 1938-bp open reading frame encoding 646 amino acid residues. The amino acid sequence of the AChE deduced from the cDNA consists of 30 residues for a putative signal peptide and 616 residues for the mature protein with a predicted molecular weight of 69,418. The three residues (Ser242, Glu371, and His485) that putatively form the catalytic triad and the six Cys that form intra-subunit disulfide bonds are completely conserved, and 10 out of the 14 aromatic residues lining the active site gorge of the AChE are also conserved. Northern blot analysis of poly(A)+ RNA showed an approximately 2.6-kb transcript, and Southern blot analysis revealed there likely was just a single copy of this gene in N. lugens. The deduced protein sequence is most similar to AChE of Nephotettix cincticeps with 83% amino acid identity. Phylogenetic analysis constructed with 45 AChEs from 30 species showed that the deduced N. lugens AChE formed a cluster with the other 8 insect AChE2s. Additionally, the hypervariable region and amino acids specific to insect AChE2 also existed in the AChE of N. lugens. The results revealed that the AChE cDNA cloned in this work belongs to insect AChE2 subgroup, which is orthologous to Drosophila AChE. Comparison of the AChEs between the susceptible and resistant strains revealed a point mutation, Gly185Ser, is likely responsible for the insensitivity of the AChE to methamidopho in the resistant strain.

Annotated ESTs from various tissues of the brown planthopper Nilaparvata lugens: a genomic resource for studying agricultural pests.

Science.gov (United States)

Noda, Hiroaki; Kawai, Sawako; Koizumi, Yoko; Matsui, Kageaki; Zhang, Qiang; Furukawa, Shigetoyo; Shimomura, Michihiko; Mita, Kazuei

2008-03-03

The brown planthopper (BPH), Nilaparvata lugens (Hemiptera, Delphacidae), is a serious insect pests of rice plants. Major means of BPH control are application of agricultural chemicals and cultivation of BPH resistant rice varieties. Nevertheless, BPH strains that are resistant to agricultural chemicals have developed, and BPH strains have appeared that are virulent against the resistant rice varieties. Expressed sequence tag (EST) analysis and related applications are useful to elucidate the mechanisms of resistance and virulence and to reveal physiological aspects of this non-model insect, with its poorly understood genetic background. More than 37,000 high-quality ESTs, excluding sequences of mitochondrial genome, microbial genomes, and rDNA, have been produced from 18 libraries of various BPH tissues and stages. About 10,200 clusters have been made from whole EST sequences, with average EST size of 627 bp. Among the top ten most abundantly expressed genes, three are unique and show no homology in BLAST searches. The actin gene was highly expressed in BPH, especially in the thorax. Tissue-specifically expressed genes were extracted based on the expression frequency among the libraries. An EST database is available at our web site. The EST library will provide useful information for transcriptional analyses, proteomic analyses, and gene functional analyses of BPH. Moreover, specific genes for hemimetabolous insects will be identified. The microarray fabricated based on the EST information will be useful for finding genes related to agricultural and biological problems related to this pest.

Characterization and comparative analysis of small RNAs in three small RNA libraries of the brown planthopper (Nilaparvata lugens).

Science.gov (United States)

Chen, Qiuhong; Lu, Lin; Hua, Hongxia; Zhou, Fei; Lu, Liaoxun; Lin, Yongjun

2012-01-01

The brown planthopper (BPH), Nilaparvata lugens (Stå;l), which belongs to Homopteran, Delphacidae, is one of the most serious and destructive pests of rice. Feeding BPH with homologous dsRNA in vitro can lead to the death of BPH, which gives a valuable clue to the prevention and control of this pest, however, we know little about its small RNA world. Small RNA libraries for three developmental stages of BPH (CX-male adult, CC-female adult, CY-last instar female nymph) had been constructed and sequenced. It revealed a prolific small RNA world of BPH. We obtained a final list of 452 (CX), 430 (CC), and 381 (CY) conserved microRNAs (miRNAs), respectively, as well as a total of 71 new miRNAs in the three libraries. All the miRNAs had their own expression profiles in the three libraries. The phylogenic evolution of the miRNA families in BPH was consistent with other species. The new miRNA sequences demonstrated some base biases. Our study discovered a large number of small RNAs through deep sequencing of three small RNA libraries of BPH. Many animal-conserved miRNA families as well as some novel miRNAs have been detected in our libraries. This is the first achievement to discover the small RNA world of BPH. A lot of new valuable information about BPH small RNAs has been revealed which was helpful for studying insect molecular biology and insect resistant research.

Interaction of Ferulic Acid with Glutathione S-Transferase and Carboxylesterase Genes in the Brown Planthopper, Nilaparvata lugens.

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Yang, Jun; Sun, Xiao-Qin; Yan, Shu-Ying; Pan, Wen-Jun; Zhang, Mao-Xin; Cai, Qing-Nian

2017-07-01

Plant phenolics are crucial defense phytochemicals against herbivores and glutathione S-transferase (GST) and carboxylesterase (CarE) in herbivorous insects are well-known detoxification enzymes for such xenobiotics. To understand relationship between a plant phenolic and herbivore GST or CarE genes, we evaluated the relationship between a rice phenolic ferulic acid and resistance to brown planthopper (BPH, Nilaparvata lugens), and investigated the interaction of ferulic acid with GST or CarE genes in BPH. The results indicate that ferulic acid content in tested rice varieties was highly associated with resistance to BPH. Bioassays using artificial diets show that the phenolic acid toxicity to BPH was dose dependent and the LC 25 and LC 50 were 5.81 and 23.30 μg/ml at 72 hr, respectively. Activities of the enzymes BPH GST and CarE were increased at concentrations below the LC 50 of ferulic acid. Moreover, low ferulic acid concentrations (gene silencing (DIGS) of GST or CarE, it was shown that suppressed expression levels of NlGSTD1, NlGSTE1 and NlCE were 14.6%-21.2%, 27.8%-34.2%, and 10.5%-19.8%, respectively. Combination of NlGSTD1, NlGSTE1 or NlCE knockdown with ferulic acid increased nymph mortality by 92.9%, 119.9%, or 124.6%, respectively. These results suggest that depletion of detoxification genes in herbivorous insects by plant-mediated RNAi technology might be a new potential resource for improving rice resistance to BPH.

Two whitebacked planthopper resistance genes in rice share the same loci with those for brown planthopper resistance.

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Tan, G X; Weng, Q M; Ren, X; Huang, Z; Zhu, L L; He, G C

2004-03-01

The whitebacked planthopper (WBPH), Sogatella furcifera, and brown planthopper (BPH) Nilaparvata lugens Stål are important sucking insects of rice (Oryza sativa L.) crops throughout the world. Rice 'B5', which has derived its resistance genes from the wild rice O. officinalis Wall ex Watt, is a line that is highly resistant to both WBPH and BPH. Previously, two resistance genes against BPH, Qbp1, and Qbp2 in 'B5' had been mapped onto chromosome 3 and chromosome 4, respectively. In this study, we employed a mapping population composed of 187 recombinant inbred lines (RILs), produced from a cross between 'B5' and susceptible variety 'Minghui63', to locate the WBPH and BPH resistance genes. A RFLP survey of the bulked extremes from the RIL population identified two genomic regions, one on chromosome 3 and the other on chromosome 4, likely containing the resistance genes to planthoppers. QTL analysis of the RILs further confirmed that two WBPH resistance genes were mapped on the same loci as Qbp1 and Qbp2, using a linkage map with 242 molecular markers distributed on 12 rice chromosomes. Of the two WBPH resistance genes, one designated Wbph7(t) was located within a 1.1-cM region between R1925 and G1318 on chromosome 3, the other designated Wbph8(t) was within a 0.3-cM region flanked by R288 and S11182 on chromosome 4. A two-way analysis of variance showed that two loci acted independently with each other in determining WBPH resistance. The results have significant implications in studying the interactions between sucking insects and plants and in breeding programs of resistance to rice planthoppers.

Field-evolved resistance to imidacloprid and ethiprole in populations of brown planthopper Nilaparvata lugens collected from across South and East Asia.

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Garrood, William T; Zimmer, Christoph T; Gorman, Kevin J; Nauen, Ralf; Bass, Chris; Davies, Thomas G E

2016-01-01

We report on the status of imidacloprid and ethiprole resistance in Nilaparvata lugens Stål collected from across South and East Asia over the period 2005-2012. A resistance survey found that field populations had developed up to 220-fold resistance to imidacloprid and 223-fold resistance to ethiprole, and that many of the strains collected showed high levels of resistance to both insecticides. We also found that the cytochrome P450 CYP6ER1 was significantly overexpressed in 12 imidacloprid-resistant populations tested when compared with a laboratory susceptible strain, with fold changes ranging from ten- to 90-fold. In contrast, another cytochrome P450 CYP6AY1, also implicated in imidacloprid resistance, was underexpressed in ten of the populations and only significantly overexpressed (3.5-fold) in a single population from India compared with the same susceptible strain. Further selection of two of the imidacloprid-resistant field strains correlated with an approximate threefold increase in expression of CYP6ER1. We conclude that overexpression of CYP6ER1 is associated with field-evolved resistance to imidacloprid in brown planthopper populations in five countries in South and East Asia. © 2015 The Authors. Pest Management Science published by John Wiley & Sons Ltd on behalf of Society of Chemical Industry.

Does Nilaparvata lugens gain tolerance to rice resistance genes through conspecifics at shared feeding sites?

NARCIS (Netherlands)

Ferrater, Jedeliza B.; Horgan, Finbarr G.

2016-01-01

This study examines the possibility of horizontal and vertical transmission of virulence (the ability to tolerate a given resistant plant or resistance gene) between individuals from brown planthopper, Nilaparvata lugens (Stål) (Hemiptera: Delphacidae), populations with distinct feeding abilities

Geographic and research center origins of rice resistance to asian planthoppers and leafhoppers: implications for rice breeding and gene deployment

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Horgan, F.G.; Srinivasan, Thanga Suja; Bentur, Jagadish S.; Kumar, R.; Bhanu, K.V.; Singh Sarao, Preetinder; Chien, Ho Van; Almazan, M.L.P.; Bernal, Carmencita C.; Ramal, Angelee Fame; Ferrater, J.B.; Huang, Shou Horng

2017-01-01

This study examines aspects of virulence to resistant rice varieties among planthoppers and leafhoppers. Using a series of resistant varieties, brown planthopper, Nilaparvata lugens, virulence was assessed in seedlings and early-tillering plants at seven research centers in South and East Asia. Virulence of the whitebacked planthopper, Sogatella furcifera, in Taiwan and the Philippines was also assessed. Phylogenetic analysis of the varieties using single-nucleotide polymorphisms (SNPs) indic...

Genome-wide mapping of virulence in brown planthopper identifies loci that break down host plant resistance.

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Jing, Shengli; Zhang, Lei; Ma, Yinhua; Liu, Bingfang; Zhao, Yan; Yu, Hangjin; Zhou, Xi; Qin, Rui; Zhu, Lili; He, Guangcun

2014-01-01

Insects and plants have coexisted for over 350 million years and their interactions have affected ecosystems and agricultural practices worldwide. Variation in herbivorous insects' virulence to circumvent host resistance has been extensively documented. However, despite decades of investigation, the genetic foundations of virulence are currently unknown. The brown planthopper (Nilaparvata lugens) is the most destructive rice (Oryza sativa) pest in the world. The identification of the resistance gene Bph1 and its introduction in commercial rice varieties prompted the emergence of a new virulent brown planthopper biotype that was able to break the resistance conferred by Bph1. In this study, we aimed to construct a high density linkage map for the brown planthopper and identify the loci responsible for its virulence in order to determine their genetic architecture. Based on genotyping data for hundreds of molecular markers in three mapping populations, we constructed the most comprehensive linkage map available for this species, covering 96.6% of its genome. Fifteen chromosomes were anchored with 124 gene-specific markers. Using genome-wide scanning and interval mapping, the Qhp7 locus that governs preference for Bph1 plants was mapped to a 0.1 cM region of chromosome 7. In addition, two major QTLs that govern the rate of insect growth on resistant rice plants were identified on chromosomes 5 (Qgr5) and 14 (Qgr14). This is the first study to successfully locate virulence in the genome of this important agricultural insect by marker-based genetic mapping. Our results show that the virulence which overcomes the resistance conferred by Bph1 is controlled by a few major genes and that the components of virulence originate from independent genetic characters. The isolation of these loci will enable the elucidation of the molecular mechanisms underpinning the rice-brown planthopper interaction and facilitate the development of durable approaches for controlling this most

Genome-wide mapping of virulence in brown planthopper identifies loci that break down host plant resistance.

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Shengli Jing

Full Text Available Insects and plants have coexisted for over 350 million years and their interactions have affected ecosystems and agricultural practices worldwide. Variation in herbivorous insects' virulence to circumvent host resistance has been extensively documented. However, despite decades of investigation, the genetic foundations of virulence are currently unknown. The brown planthopper (Nilaparvata lugens is the most destructive rice (Oryza sativa pest in the world. The identification of the resistance gene Bph1 and its introduction in commercial rice varieties prompted the emergence of a new virulent brown planthopper biotype that was able to break the resistance conferred by Bph1. In this study, we aimed to construct a high density linkage map for the brown planthopper and identify the loci responsible for its virulence in order to determine their genetic architecture. Based on genotyping data for hundreds of molecular markers in three mapping populations, we constructed the most comprehensive linkage map available for this species, covering 96.6% of its genome. Fifteen chromosomes were anchored with 124 gene-specific markers. Using genome-wide scanning and interval mapping, the Qhp7 locus that governs preference for Bph1 plants was mapped to a 0.1 cM region of chromosome 7. In addition, two major QTLs that govern the rate of insect growth on resistant rice plants were identified on chromosomes 5 (Qgr5 and 14 (Qgr14. This is the first study to successfully locate virulence in the genome of this important agricultural insect by marker-based genetic mapping. Our results show that the virulence which overcomes the resistance conferred by Bph1 is controlled by a few major genes and that the components of virulence originate from independent genetic characters. The isolation of these loci will enable the elucidation of the molecular mechanisms underpinning the rice-brown planthopper interaction and facilitate the development of durable approaches for

Mucin-like protein, a saliva component involved in brown planthopper virulence and host adaptation.

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Huang, Hai-Jian; Liu, Cheng-Wen; Xu, Hai-Jun; Bao, Yan-Yuan; Zhang, Chuan-Xi

2017-04-01

The rice brown planthopper (BPH), Nilaparvata lugens, can rapidly adapt to new resistant rice varieties within several generations, rendering its management burdensome. However, the molecular mechanism underlying its adaptability remains unclear. In this study, we investigated the potential role of mucin-like protein (NlMul) in N. lugens virulence and adaptation to host resistance. NlMul is an important glycoprotein that constitutes both gelling and watery saliva, and specifically expressed in the salivary glands at all developmental stages except the egg period. Knocking down the expression of NlMul resulted in the secretion of short and single-branched salivary sheaths. NlMul might help BPH deal with plant resistance, and altered gene expression was observed when BPHs were transferred from a susceptible rice variety to a resistant one. The NlMul-deficient BPHs showed disordered developmental duration and a portion of these insects reared on resistant rice exhibited lethal effects. Our results uncover a saliva-mediated interaction between insect and host plant, and provide useful information in rice breeding and planthopper management. Copyright © 2017 Elsevier Ltd. All rights reserved.

A nicotinic acetylcholine receptor mutation conferring target-site resistance to imidacloprid in Nilaparvata lugens (brown planthopper).

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Liu, Zewen; Williamson, Martin S; Lansdell, Stuart J; Denholm, Ian; Han, Zhaojun; Millar, Neil S

2005-06-14

Neonicotinoids, such as imidacloprid, are nicotinic acetylcholine receptor (nAChR) agonists with potent insecticidal activity. Since its introduction in the early 1990s, imidacloprid has become one of the most extensively used insecticides for both crop protection and animal health applications. As with other classes of insecticides, resistance to neonicotinoids is a significant threat and has been identified in several pest species, including the brown planthopper, Nilaparvata lugens, a major rice pest in many parts of Asia. In this study, radioligand binding experiments have been conducted with whole-body membranes prepared from imidacloprid-susceptible and imidacloprid-resistant strains of N. lugens. The results reveal a much higher level of [3H]imidacloprid-specific binding to the susceptible strain than to the resistant strain (16.7 +/- 1.0 and 0.34 +/- 0.21 fmol/mg of protein, respectively). With the aim of understanding the molecular basis of imidacloprid resistance, five nAChR subunits (Nlalpha1-Nlalpha4 and Nlbeta1) have been cloned from N. lugens.A comparison of nAChR subunit genes from imidacloprid-sensitive and imidacloprid-resistant populations has identified a single point mutation at a conserved position (Y151S) in two nAChR subunits, Nlalpha1 and Nlalpha3. A strong correlation between the frequency of the Y151S point mutation and the level of resistance to imidacloprid has been demonstrated by allele-specific PCR. By expression of hybrid nAChRs containing N. lugens alpha and rat beta2 subunits, evidence was obtained that demonstrates that mutation Y151S is responsible for a substantial reduction in specific [3H]imidacloprid binding. This study provides direct evidence for the occurrence of target-site resistance to a neonicotinoid insecticide.

Annotated ESTs from various tissues of the brown planthopper Nilaparvata lugens: A genomic resource for studying agricultural pests

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Zhang Qiang

2008-03-01

Full Text Available Abstract Background The brown planthopper (BPH, Nilaparvata lugens (Hemiptera, Delphacidae, is a serious insect pests of rice plants. Major means of BPH control are application of agricultural chemicals and cultivation of BPH resistant rice varieties. Nevertheless, BPH strains that are resistant to agricultural chemicals have developed, and BPH strains have appeared that are virulent against the resistant rice varieties. Expressed sequence tag (EST analysis and related applications are useful to elucidate the mechanisms of resistance and virulence and to reveal physiological aspects of this non-model insect, with its poorly understood genetic background. Results More than 37,000 high-quality ESTs, excluding sequences of mitochondrial genome, microbial genomes, and rDNA, have been produced from 18 libraries of various BPH tissues and stages. About 10,200 clusters have been made from whole EST sequences, with average EST size of 627 bp. Among the top ten most abundantly expressed genes, three are unique and show no homology in BLAST searches. The actin gene was highly expressed in BPH, especially in the thorax. Tissue-specifically expressed genes were extracted based on the expression frequency among the libraries. An EST database is available at our web site. Conclusion The EST library will provide useful information for transcriptional analyses, proteomic analyses, and gene functional analyses of BPH. Moreover, specific genes for hemimetabolous insects will be identified. The microarray fabricated based on the EST information will be useful for finding genes related to agricultural and biological problems related to this pest.

Characterization and comparative analysis of small RNAs in three small RNA libraries of the brown planthopper (Nilaparvata lugens.

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Qiuhong Chen

Full Text Available BACKGROUND: The brown planthopper (BPH, Nilaparvata lugens (Stå;l, which belongs to Homopteran, Delphacidae, is one of the most serious and destructive pests of rice. Feeding BPH with homologous dsRNA in vitro can lead to the death of BPH, which gives a valuable clue to the prevention and control of this pest, however, we know little about its small RNA world. METHODOLOGY/PRINCIPAL FINDINGS: Small RNA libraries for three developmental stages of BPH (CX-male adult, CC-female adult, CY-last instar female nymph had been constructed and sequenced. It revealed a prolific small RNA world of BPH. We obtained a final list of 452 (CX, 430 (CC, and 381 (CY conserved microRNAs (miRNAs, respectively, as well as a total of 71 new miRNAs in the three libraries. All the miRNAs had their own expression profiles in the three libraries. The phylogenic evolution of the miRNA families in BPH was consistent with other species. The new miRNA sequences demonstrated some base biases. CONCLUSION: Our study discovered a large number of small RNAs through deep sequencing of three small RNA libraries of BPH. Many animal-conserved miRNA families as well as some novel miRNAs have been detected in our libraries. This is the first achievement to discover the small RNA world of BPH. A lot of new valuable information about BPH small RNAs has been revealed which was helpful for studying insect molecular biology and insect resistant research.

A salivary EF-hand calcium-binding protein of the brown planthopper Nilaparvata lugens functions as an effector for defense responses in rice

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Ye, Wenfeng; Yu, Haixin; Jian, Yukun; Zeng, Jiamei; Ji, Rui; Chen, Hongdan; Lou, Yonggen

2017-01-01

The brown planthopper (BPH), Nilaparvata lugens (Stål) (Hemiptera: Delphacidae), a major pest of rice in Asia, is able to successfully puncture sieve tubes in rice with its piercing stylet and then to ingest phloem sap. How BPH manages to continuously feed on rice remains unclear. Here, we cloned the gene NlSEF1, which is highly expressed in the salivary glands of BPH. The NlSEF1 protein has EF-hand Ca2+-binding activity and can be secreted into rice plants when BPH feed. Infestation of rice by BPH nymphs whose NlSEF1 was knocked down elicited higher levels of Ca2+ and H2O2 but not jasmonic acid, jasmonoyl-isoleucine (JA-Ile) and SA in rice than did infestation by control nymphs; Consistently, wounding plus the recombination protein NlSEF1 suppressed the production of H2O2 in rice. Bioassays revealed that NlSEF1-knockdown BPH nymphs had a higher mortality rate and lower feeding capacity on rice than control nymphs. These results indicate that the salivary protein in BPH, NlSEF1, functions as an effector and plays important roles in interactions between BPH and rice by mediating the plant’s defense responses. PMID:28098179

Identification of promoter polymorphisms in the cytochrome P450 CYP6AY1 linked with insecticide resistance in the brown planthopper, Nilaparvata lugens.

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Pang, R; Li, Y; Dong, Y; Liang, Z; Zhang, Y; Zhang, W

2014-12-01

Imidacloprid resistance in the brown planthopper, Nilaparvata lugens, is primarily the result of the over-expression of cytochrome P450 monooxygenases. Here, a field-collected strain of N. lugens was shown to be highly resistant to both imidacloprid and buprofezin. Insecticide exposure and quantitative real-time PCR revealed that its resistance was mainly associated with a cytochrome P450 gene, CYP6AY1. CYP6AY1 is known to metabolize imidacloprid but its effect on buprofezin is unclear. In the 5'-untranslated region of CYP6AY1, a novel alternative splicing was detected. After a 1990-bp promoter region was cloned, its basal luciferase activity was assessed. Furthermore, genotyping studies identified 12 variations in the promoter region that discriminated between the field-collected and control strain. Finally, survival bioassays revealed a single nucleotide polymorphism and an insertion-deletion polymorphism linked to buprofezin and imidacloprid resistance. Mutagenesis of these sites enhanced the promoter activity of CYP6AY1. These results suggest that promoter polymorphisms may affect P450-mediated multiple insecticide resistance of pests. © 2014 The Royal Entomological Society.

Mapping and pyramiding of two major genes for resistance to the brown planthopper (Nilaparvata lugens [Stål]) in the rice cultivar ADR52.

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Myint, Khin Khin Marlar; Fujita, Daisuke; Matsumura, Masaya; Sonoda, Tomohiro; Yoshimura, Atsushi; Yasui, Hideshi

2012-02-01

The brown planthopper (BPH), Nilaparvata lugens (Stål), is one of the most serious and destructive pests of rice, and can be found throughout the rice-growing areas of Asia. To date, more than 24 major BPH-resistance genes have been reported in several Oryza sativa ssp. indica cultivars and wild relatives. Here, we report the genetic basis of the high level of BPH resistance derived from an Indian rice cultivar, ADR52, which was previously identified as resistant to the whitebacked planthopper (Sogatella furcifera [Horváth]). An F(2) population derived from a cross between ADR52 and a susceptible cultivar, Taichung 65 (T65), was used for quantitative trait locus (QTL) analysis. Antibiosis testing showed that multiple loci controlled the high level of BPH resistance in this F(2) population. Further linkage analysis using backcross populations resulted in the identification of BPH-resistance (antibiosis) gene loci from ADR52. BPH25 co-segregated with marker S00310 on the distal end of the short arm of chromosome 6, and BPH26 co-segregated with marker RM5479 on the long arm of chromosome 12. To characterize the virulence of the most recently migrated BPH strain in Japan, preliminary near-isogenic lines (pre-NILs) and a preliminary pyramided line (pre-PYL) carrying BPH25 and BPH26 were evaluated. Although both pre-NILs were susceptible to the virulent BPH strain, the pre-PYL exhibited a high level of resistance. The pyramiding of resistance genes is therefore likely to be effective for increasing the durability of resistance against the new virulent BPH strain in Japan.

Overexpression of a cytochrome P450 monooxygenase, CYP6ER1, is associated with resistance to imidacloprid in the brown planthopper, Nilaparvata lugens.

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Bass, C; Carvalho, R A; Oliphant, L; Puinean, A M; Field, L M; Nauen, R; Williamson, M S; Moores, G; Gorman, K

2011-12-01

The brown planthopper, Nilaparvata lugens, is an economically significant pest of rice throughout Asia and has evolved resistance to many insecticides including the neonicotinoid imidacloprid. The resistance of field populations of N. lugens to imidacloprid has been attributed to enhanced detoxification by cytochrome P450 monooxygenases (P450s), although, to date, the causative P450(s) has (have) not been identified. In the present study, biochemical assays using the model substrate 7-ethoxycoumarin showed enhanced P450 activity in several resistant N. lugens field strains when compared with a susceptible reference strain. Thirty three cDNA sequences encoding tentative unique P450s were identified from two recent sequencing projects and by degenerate PCR. The mRNA expression level of 32 of these was examined in susceptible, moderately resistant and highly resistant N. lugens strains using quantitative real-time PCR. A single P450 gene (CYP6ER1) was highly overexpressed in all resistant strains (up to 40-fold) and the level of expression observed in the different N. lugens strains was significantly correlated with the resistance phenotype. These results provide strong evidence for a role of CYP6ER1 in the resistance of N. lugens to imidacloprid. © 2011 The Authors. Insect Molecular Biology © 2011 The Royal Entomological Society.

Molecular dynamics of detoxification and toxin-tolerance genes in brown planthopper (Nilaparvata lugens Stål., Homoptera: Delphacidae) feeding on resistant rice plants.

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Yang, Zhifan; Zhang, Futie; He, Qing; He, Guangcun

2005-06-01

To investigate the molecular response of brown planthopper, Nilaparvata lugens (BPH) to BPH-resistant rice plants, we isolated cDNA fragments of the genes encoding for carboxylesterase (CAR), trypsin (TRY), cytochrome P450 monooxygenase (P450), NADH-quinone oxidoreductase (NQO), acetylcholinesterase (ACE), and Glutathione S-transferase (GST). Expression profiles of the genes were monitored on fourth instar nymphs feeding on rice varieties with different resistance levels. Northern blot hybridization showed that, compared with BPH reared on susceptible rice TN1, expression of the genes for P450 and CAR was apparently up-regulated and TRY mRNA decreased in BPH feeding on a highly resistant rice line B5 and a moderately resistant rice variety MH63, respectively. Two transcripts of GST increased in BPH feeding on B5; but in BPH feeding on MH63, this gene was inducible and its expression reached a maximum level at 24 h, and then decreased slightly. The expression of NQO gene was enhanced in BPH on B5 plants but showed a constant expression in BPH on MH63 plants. No difference in ACE gene expression among BPH on different rice plants was detected by the RT-PCR method. The results suggest these genes may play important roles in the defense response of BPH to resistant rice.

GENETICS OF BROWN PLANTHOPPER (NILAPARVATA LUGENS STAL.) RESISTANCE IN ELITE DONORS OF RICE (ORYZA SATIVA L.)

OpenAIRE

B BALAKRISHNA; P V SATAYANARAYANA

2013-01-01

The inheritance of resistance to the brown planthopper (BPH) in four BPH resistant donors of rice i. e., Sinna Sivappu, Sudu Hondarawala, PTB 33 and BM 71 was studied both in field and greenhouse conditions. The F2 population of crosses involving donors Sinna Sivappu, Sudu Hondarawala and PTB 33 fit into the ratio of 13:3 indicating the resistance to BPH was controlled by two genes i. e., one dominant and one recessive gene segregating independent to each other. The F2 populat...

No impact of transgenic cry1C rice on the rove beetle Paederus fuscipes, a generalist predator of brown planthopper Nilaparvata lugens

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Meng, Jiarong; Mabubu, Juma Ibrahim; Han, Yu; He, Yueping; Zhao, Jing; Hua, Hongxia; Feng, Yanni; Wu, Gang

2016-07-01

T1C-19 is newly developed transgenic rice active against lepidopteran pests, and expresses a synthesized cry1C gene driven by the maize ubiquitin promoter. The brown planthopper, Nilaparvata lugens, is a major non-target pest of rice, and the rove beetle (Paederus fuscipes) is a generalist predator of N. lugens nymphs. As P. fuscipes may be exposed to the Cry1C protein through preying on N. lugens, it is essential to assess the potential effects of transgenic cry1C rice on this predator. In this study, two experiments (a direct feeding experiment and a tritrophic experiment) were conducted to evaluate the ecological risk of cry1C rice to P. fuscipes. No significant negative effects were observed in the development, survival, female ratio and body weight of P. fuscipes in both treatments of direct exposure to elevated doses of Cry1C protein and prey-mediated exposure to realistic doses of the protein. This indicated that cry1C rice had no detrimental effects on P. fuscipes. This work represents the first study of an assessment continuum for the effects of transgenic cry1C rice on P. fuscipes. Use of the rove beetle as an indicator species to assess potential effects of genetically modified crops on non-target arthropods is feasible.

An adenylyl cyclase like-9 gene (NlAC9) influences growth and fecundity in the brown planthopper, Nilaparvata lugens (Stål) (Hemiptera: Delphacidae).

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Ge, LinQuan; Gu, HaoTian; Huang, Bo; Song, Qisheng; Stanley, David; Liu, Fang; Yang, Guo-Qing; Wu, Jin-Cai

2017-01-01

The cAMP/PKA intracellular signaling pathway is launched by adenylyl cyclase (AC) conversion of adenosine triphosphate (ATP) to 3', 5'-cyclic AMP (cAMP) and cAMP-dependent activation of PKA. Although this pathway is very well known in insect physiology, there is little to no information on it in some very small pest insects, such as the brown planthopper (BPH), Nilaparvata lugens Stål. BPH is a destructive pest responsible for tremendous crop losses in rice cropping systems. We are investigating the potentials of novel pest management technologies from RNA interference perspective. Based on analysis of transcriptomic data, the BPH AC like-9 gene (NlAC9) was up-regulated in post-mating females, which led us to pose the hypothesis that NlAC9 is a target gene that would lead to reduced BPH fitness and populations. Targeting NlAC9 led to substantially decreased soluble ovarian protein content, yeast-like symbiont abundance, and vitellogenin gene expression, accompanied with stunted ovarian development and body size. Eggs laid were decreased and oviposition period shortened. Taken together, our findings indicated that NlAC9 exerted pronounced effects on female fecundity, growth and longevity, which strongly supports our hypothesis.

An adenylyl cyclase like-9 gene (NlAC9 influences growth and fecundity in the brown planthopper, Nilaparvata lugens (Stål (Hemiptera: Delphacidae.

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LinQuan Ge

Full Text Available The cAMP/PKA intracellular signaling pathway is launched by adenylyl cyclase (AC conversion of adenosine triphosphate (ATP to 3', 5'-cyclic AMP (cAMP and cAMP-dependent activation of PKA. Although this pathway is very well known in insect physiology, there is little to no information on it in some very small pest insects, such as the brown planthopper (BPH, Nilaparvata lugens Stål. BPH is a destructive pest responsible for tremendous crop losses in rice cropping systems. We are investigating the potentials of novel pest management technologies from RNA interference perspective. Based on analysis of transcriptomic data, the BPH AC like-9 gene (NlAC9 was up-regulated in post-mating females, which led us to pose the hypothesis that NlAC9 is a target gene that would lead to reduced BPH fitness and populations. Targeting NlAC9 led to substantially decreased soluble ovarian protein content, yeast-like symbiont abundance, and vitellogenin gene expression, accompanied with stunted ovarian development and body size. Eggs laid were decreased and oviposition period shortened. Taken together, our findings indicated that NlAC9 exerted pronounced effects on female fecundity, growth and longevity, which strongly supports our hypothesis.

Transcriptome analysis of fat bodies from two brown planthopper (Nilaparvata lugens) populations with different virulence levels in rice.

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Yu, Haixin; Ji, Rui; Ye, Wenfeng; Chen, Hongdan; Lai, Wenxiang; Fu, Qiang; Lou, Yonggen

2014-01-01

The brown planthopper (BPH), Nilaparvata lugens (Stål), one of the most serious rice insect pests in Asia, can quickly overcome rice resistance by evolving new virulent populations. The insect fat body plays essential roles in the life cycles of insects and in plant-insect interactions. However, whether differences in fat body transcriptomes exist between insect populations with different virulence levels and whether the transcriptomic differences are related to insect virulence remain largely unknown. In this study, we performed transcriptome-wide analyses on the fat bodies of two BPH populations with different virulence levels in rice. The populations were derived from rice variety TN1 (TN1 population) and Mudgo (M population). In total, 33,776 and 32,332 unigenes from the fat bodies of TN1 and M populations, respectively, were generated using Illumina technology. Gene ontology annotations and Kyoto Encyclopedia of Genes and Genomes (KEGG) orthology classifications indicated that genes related to metabolism and immunity were significantly active in the fat bodies. In addition, a total of 339 unigenes showed homology to genes of yeast-like symbionts (YLSs) from 12 genera and endosymbiotic bacteria Wolbachia. A comparative analysis of the two transcriptomes generated 7,860 differentially expressed genes. GO annotations and enrichment analysis of KEGG pathways indicated these differentially expressed transcripts might be involved in metabolism and immunity. Finally, 105 differentially expressed genes from YLSs and Wolbachia were identified, genes which might be associated with the formation of different virulent populations. This study was the first to compare the fat-body transcriptomes of two BPH populations having different virulence traits and to find genes that may be related to this difference. Our findings provide a molecular resource for future investigations of fat bodies and will be useful in examining the interactions between the fat body and virulence

Comparative transcriptome analysis of salivary glands of two populations of rice brown planthopper, Nilaparvata lugens, that differ in virulence.

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Ji, Rui; Yu, Haixin; Fu, Qiang; Chen, Hongdan; Ye, Wenfeng; Li, Shaohui; Lou, Yonggen

2013-01-01

The brown planthopper (BPH), Nilaparvata lugens (Stål), a destructive rice pest in Asia, can quickly overcome rice resistance by evolving new virulent populations. Herbivore saliva plays an important role in plant-herbivore interactions, including in plant defense and herbivore virulence. However, thus far little is known about BPH saliva at the molecular level, especially its role in virulence and BPH-rice interaction. Using cDNA amplification in combination with Illumina short-read sequencing technology, we sequenced the salivary-gland transcriptomes of two BPH populations with different virulence; the populations were derived from rice variety TN1 (TN1 population) and Mudgo (M population). In total, 37,666 and 38,451 unigenes were generated from the salivary glands of these populations, respectively. When combined, a total of 43,312 unigenes were obtained, about 18 times more than the number of expressed sequence tags previously identified from these glands. Gene ontology annotations and KEGG orthology classifications indicated that genes related to metabolism, binding and transport were significantly active in the salivary glands. A total of 352 genes were predicted to encode secretory proteins, and some might play important roles in BPH feeding and BPH-rice interactions. Comparative analysis of the transcriptomes of the two populations revealed that the genes related to 'metabolism,' 'digestion and absorption,' and 'salivary secretion' might be associated with virulence. Moreover, 67 genes encoding putative secreted proteins were differentially expressed between the two populations, suggesting these genes may contribute to the change in virulence. This study was the first to compare the salivary-gland transcriptomes of two BPH populations having different virulence traits and to find genes that may be related to this difference. Our data provide a rich molecular resource for future functional studies on salivary glands and will be useful for elucidating the

Transcriptome analysis of fat bodies from two brown planthopper (Nilaparvata lugens populations with different virulence levels in rice.

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Haixin Yu

Full Text Available BACKGROUND: The brown planthopper (BPH, Nilaparvata lugens (Stål, one of the most serious rice insect pests in Asia, can quickly overcome rice resistance by evolving new virulent populations. The insect fat body plays essential roles in the life cycles of insects and in plant-insect interactions. However, whether differences in fat body transcriptomes exist between insect populations with different virulence levels and whether the transcriptomic differences are related to insect virulence remain largely unknown. METHODOLOGY/PRINCIPAL FINDINGS: In this study, we performed transcriptome-wide analyses on the fat bodies of two BPH populations with different virulence levels in rice. The populations were derived from rice variety TN1 (TN1 population and Mudgo (M population. In total, 33,776 and 32,332 unigenes from the fat bodies of TN1 and M populations, respectively, were generated using Illumina technology. Gene ontology annotations and Kyoto Encyclopedia of Genes and Genomes (KEGG orthology classifications indicated that genes related to metabolism and immunity were significantly active in the fat bodies. In addition, a total of 339 unigenes showed homology to genes of yeast-like symbionts (YLSs from 12 genera and endosymbiotic bacteria Wolbachia. A comparative analysis of the two transcriptomes generated 7,860 differentially expressed genes. GO annotations and enrichment analysis of KEGG pathways indicated these differentially expressed transcripts might be involved in metabolism and immunity. Finally, 105 differentially expressed genes from YLSs and Wolbachia were identified, genes which might be associated with the formation of different virulent populations. CONCLUSIONS/SIGNIFICANCE: This study was the first to compare the fat-body transcriptomes of two BPH populations having different virulence traits and to find genes that may be related to this difference. Our findings provide a molecular resource for future investigations of fat bodies

Transcriptome Analysis of Fat Bodies from Two Brown Planthopper (Nilaparvata lugens) Populations with Different Virulence Levels in Rice

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Chen, Hongdan; Lai, Wenxiang; Fu, Qiang; Lou, Yonggen

2014-01-01

Background The brown planthopper (BPH), Nilaparvata lugens (Stål), one of the most serious rice insect pests in Asia, can quickly overcome rice resistance by evolving new virulent populations. The insect fat body plays essential roles in the life cycles of insects and in plant-insect interactions. However, whether differences in fat body transcriptomes exist between insect populations with different virulence levels and whether the transcriptomic differences are related to insect virulence remain largely unknown. Methodology/Principal Findings In this study, we performed transcriptome-wide analyses on the fat bodies of two BPH populations with different virulence levels in rice. The populations were derived from rice variety TN1 (TN1 population) and Mudgo (M population). In total, 33,776 and 32,332 unigenes from the fat bodies of TN1 and M populations, respectively, were generated using Illumina technology. Gene ontology annotations and Kyoto Encyclopedia of Genes and Genomes (KEGG) orthology classifications indicated that genes related to metabolism and immunity were significantly active in the fat bodies. In addition, a total of 339 unigenes showed homology to genes of yeast-like symbionts (YLSs) from 12 genera and endosymbiotic bacteria Wolbachia. A comparative analysis of the two transcriptomes generated 7,860 differentially expressed genes. GO annotations and enrichment analysis of KEGG pathways indicated these differentially expressed transcripts might be involved in metabolism and immunity. Finally, 105 differentially expressed genes from YLSs and Wolbachia were identified, genes which might be associated with the formation of different virulent populations. Conclusions/Significance This study was the first to compare the fat-body transcriptomes of two BPH populations having different virulence traits and to find genes that may be related to this difference. Our findings provide a molecular resource for future investigations of fat bodies and will be useful

Establishing the role of detoxifying enzymes in field-evolved resistance to various insecticides in the brown planthopper (Nilaparvata lugens) in South India.

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Malathi, Vijayakumar Maheshwari; Jalali, Sushil K; Gowda, Dandinashivara K Sidde; Mohan, Muthugounder; Venkatesan, Thiruvengadam

2017-02-01

The brown planthopper (BPH), Nilaparvata lugens (Stål), is one of the major pests of rice throughout Asia. Extensive use of insecticides for suppressing N. lugens has resulted in the development of insecticide resistance leading to frequent control failures in the field. The aim of the present study was to evaluate resistance in the field populations of N. lugens from major rice growing states of South India to various insecticides. We also determined the activity of detoxifying enzymes (esterases [ESTs], glutathione S-transferases [GSTs], and mixed-function oxidases [MFOs]). Moderate levels of resistance were detected in the field populations to acephate, thiamethoxam and buprofezin (resistance factors 1.05-20.92 fold, 4.52-14.99 fold, and 1.00-18.09 fold, respectively) as compared with susceptible strain while there were low levels of resistance to imidacloprid (resistance factor 1.23-6.70 fold) and complete sensitivity to etofenoprox (resistance factor 1.05-1.66 fold). EST activities in the field populations were 1.06 to 3.09 times higher than the susceptible strain while for GST and MFO the ratios varied from 1.29 to 3.41 and 1.03 to 1.76, respectively. The EST activity was found to be correlated to acephate resistance (r = 0.999, P ≥ 0.001). The high selection pressure of organophosphate, neonicotinoid, and insect growth regulator (IGR) in the field is likely to be contributing for resistance in BPH to multiple insecticides, leading to control failures. The results obtained will be beneficial to IPM recommendations for the use of effective insecticides against BPH. © 2015 Institute of Zoology, Chinese Academy of Sciences.

Comparative transcriptome analysis of salivary glands of two populations of rice brown planthopper, Nilaparvata lugens, that differ in virulence.

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Rui Ji

Full Text Available BACKGROUND: The brown planthopper (BPH, Nilaparvata lugens (Stål, a destructive rice pest in Asia, can quickly overcome rice resistance by evolving new virulent populations. Herbivore saliva plays an important role in plant-herbivore interactions, including in plant defense and herbivore virulence. However, thus far little is known about BPH saliva at the molecular level, especially its role in virulence and BPH-rice interaction. METHODOLOGY/PRINCIPAL FINDINGS: Using cDNA amplification in combination with Illumina short-read sequencing technology, we sequenced the salivary-gland transcriptomes of two BPH populations with different virulence; the populations were derived from rice variety TN1 (TN1 population and Mudgo (M population. In total, 37,666 and 38,451 unigenes were generated from the salivary glands of these populations, respectively. When combined, a total of 43,312 unigenes were obtained, about 18 times more than the number of expressed sequence tags previously identified from these glands. Gene ontology annotations and KEGG orthology classifications indicated that genes related to metabolism, binding and transport were significantly active in the salivary glands. A total of 352 genes were predicted to encode secretory proteins, and some might play important roles in BPH feeding and BPH-rice interactions. Comparative analysis of the transcriptomes of the two populations revealed that the genes related to 'metabolism,' 'digestion and absorption,' and 'salivary secretion' might be associated with virulence. Moreover, 67 genes encoding putative secreted proteins were differentially expressed between the two populations, suggesting these genes may contribute to the change in virulence. CONCLUSIONS/SIGNIFICANCE: This study was the first to compare the salivary-gland transcriptomes of two BPH populations having different virulence traits and to find genes that may be related to this difference. Our data provide a rich molecular resource for

Comparative Transcriptome Analysis of Salivary Glands of Two Populations of Rice Brown Planthopper, Nilaparvata lugens, That Differ in Virulence

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Chen, Hongdan; Ye, Wenfeng; Li, Shaohui; Lou, Yonggen

2013-01-01

Background The brown planthopper (BPH), Nilaparvata lugens (Stål), a destructive rice pest in Asia, can quickly overcome rice resistance by evolving new virulent populations. Herbivore saliva plays an important role in plant–herbivore interactions, including in plant defense and herbivore virulence. However, thus far little is known about BPH saliva at the molecular level, especially its role in virulence and BPH–rice interaction. Methodology/Principal Findings Using cDNA amplification in combination with Illumina short-read sequencing technology, we sequenced the salivary-gland transcriptomes of two BPH populations with different virulence; the populations were derived from rice variety TN1 (TN1 population) and Mudgo (M population). In total, 37,666 and 38,451 unigenes were generated from the salivary glands of these populations, respectively. When combined, a total of 43,312 unigenes were obtained, about 18 times more than the number of expressed sequence tags previously identified from these glands. Gene ontology annotations and KEGG orthology classifications indicated that genes related to metabolism, binding and transport were significantly active in the salivary glands. A total of 352 genes were predicted to encode secretory proteins, and some might play important roles in BPH feeding and BPH–rice interactions. Comparative analysis of the transcriptomes of the two populations revealed that the genes related to ‘metabolism,’ ‘digestion and absorption,’ and ‘salivary secretion’ might be associated with virulence. Moreover, 67 genes encoding putative secreted proteins were differentially expressed between the two populations, suggesting these genes may contribute to the change in virulence. Conclusions/Significance This study was the first to compare the salivary-gland transcriptomes of two BPH populations having different virulence traits and to find genes that may be related to this difference. Our data provide a rich molecular resource for

Comparative analysis of the transcriptional responses to low and high temperatures in three rice planthopper species.

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Huang, Hai-Jian; Xue, Jian; Zhuo, Ji-Chong; Cheng, Ruo-Lin; Xu, Hai-Jun; Zhang, Chuan-Xi

2017-05-01

The brown planthopper (Nilaparvata lugens, BPH), white-backed planthopper (Sogatella furcifera, WBPH) and small brown planthopper (Laodelphax striatellus, SBPH) are important rice pests in Asia. These three species differ in thermal tolerance and exhibit quite different migration and overwintering strategies. To understand the underlying mechanisms, we sequenced and compared the transcriptome of the three species under different temperature treatments. We found that metabolism-, exoskeleton- and chemosensory-related genes were modulated. In high temperature (37 °C), heat shock protein (HSP) genes were the most co-regulated; other genes related with fatty acid metabolism, amino acid metabolism and transportation were also differentially expressed. In low temperature (5 °C), the differences in gene expression of the genes for fatty acid synthesis, transport proteins and cytochrome P450 might explain why SBPH can overwinter in high latitudes, while BPH and WBPH cannot. In addition, other genes related with moulting, and membrane lipid composition might also play roles in resistance to low and high temperatures. Our study illustrates the common responses and different tolerance mechanisms of three rice planthoppers in coping with temperature change, and provides a potential strategy for pest management. © 2017 John Wiley & Sons Ltd.

Roles of NlAKTIP in the Growth and Eclosion of the Rice Brown Planthopper, Nilaparvata lugens Stål, as Revealed by RNA Interference

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Hao, Peiying; Lu, Chaofeng; Ma, Yan; Xu, Lingbo; Zhu, Jiajun; Yu, Xiaoping

2015-01-01

AKT-interacting protein (AKTIP) interacts with serine/threonine protein kinase B (PKB)/AKT. AKTIP modulates AKT’s activity by enhancing the phosphorylation of the regulatory site and plays a crucial role in multiple biological processes. In this study, the full length cDNA of NlAKTIP, a novel AKTIP gene in the brown planthopper (BPH) Nilaparvata lugens, was cloned. The reverse transcription quantitive PCR (RT-qPCR) results showed that the NlAKTIP gene was strongly expressed in gravid female adults, but was relatively weakly expressed in nymphs and male adult BPH. In female BPH, treatment with dsAKTIP resulted in the efficient silencing of NlAKTIP, leading to a significant reduction of mRNA levels, about 50% of those of the untreated control group at day 7 of the study. BPH fed with dsAKTIP had reduced growth with lower body weights and smaller sizes, and the body weight of BPH treated with dsAKTIP at day 7 decreased to about 30% of that of the untreated control. Treatment of dsAKTIP significantly delayed the eclosion for over 7 days relative to the control group and restricted ovarian development to Grade I (transparent stage), whereas the controls developed to Grade IV (matured stage). These results indicated that NlAKTIP is crucial to the growth and development of female BPH. This study provided a valuable clue of a potential target NlAKTIP for inhibiting the BPH, and also provided a new point of view on the interaction between BPH and resistant rice. PMID:26402675

Geographic and Research Center Origins of Rice Resistance to Asian Planthoppers and Leafhoppers: Implications for Rice Breeding and Gene Deployment

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Finbarr G. Horgan

2017-09-01

Full Text Available This study examines aspects of virulence to resistant rice varieties among planthoppers and leafhoppers. Using a series of resistant varieties, brown planthopper, Nilaparvata lugens, virulence was assessed in seedlings and early-tillering plants at seven research centers in South and East Asia. Virulence of the whitebacked planthopper, Sogatella furcifera, in Taiwan and the Philippines was also assessed. Phylogenetic analysis of the varieties using single-nucleotide polymorphisms (SNPs indicated a clade of highly resistant varieties from South Asia with two further South Asian clades of moderate resistance. Greenhouse bioassays indicated that planthoppers can develop virulence against multiple resistance genes including genes introgressed from wild rice species. Nilaparvata lugens populations from Punjab (India and the Mekong Delta (Vietnam were highly virulent to a range of key resistance donors irrespective of variety origin. Sogatella furcifera populations were less virulent to donors than N. lugens; however, several genes for resistance to S. furcifera are now ineffective in East Asia. A clade of International Rice Research Institute (IRRI-bred varieties and breeding lines, without identified leafhopper-resistance genes, were highly resistant to the green leafhopper, Nephotettix virescens. Routine phenotyping during breeding programs likely maintains high levels of quantitative resistance to leafhoppers. We discuss these results in the light of breeding and deploying resistant rice in Asia.

Impact of Nitrogen, Phosphorus and Potassium on Brown Planthopper and Tolerance of Its Host Rice Plants

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Md Mamunur Rashid

2016-05-01

Full Text Available The brown planthopper (BPH, Nilaparvata lugens (Stål, appeared as a devastating pest of rice in Asia. Experiments were conducted to study the effects of three nutrients, nitrogen (N, phosphorus (P and potassium (K, on BPH and its host rice plants. Biochemical constituents of BPH and rice plants with varying nutrient levels at different growth stages, and changes in relative water content (RWC of rice plants were determined in the laboratory. Feeding of BPH and the tolerance of rice plants to BPH with different nutrient levels were determined in the nethouse. Concentrations of N and P were found much higher in the BPH body than in its host rice plants, and this elemental mismatch is an inherent constraint on meeting nutritional requirements of BPH. Nitrogen was found as a more limiting element for BPH than other nutrients in rice plants. Application of N fertilizers to the rice plants increased the N concentrations both in rice plants and BPH while application of P and K fertilizers increased their concentrations in plant tissues only but not in BPH. Nitrogen application also increased the level of soluble proteins and decreased silicon content in rice plants, which resulted in increased feeding of BPH with sharp reduction of RWC in rice plants ultimately caused susceptible to the pest. P fertilization increased the concentration of P in rice plant tissues but not changed N, K, Si, free sugar and soluble protein contents, which indicated little importance of P to the feeding of BPH and tolerance of plant against BPH. K fertilization increased K content but reduced N, Si, free sugar and soluble protein contents in the plant tissues which resulted in the minimum reduction of RWC in rice plants after BPH feeding, thereby contributed to higher tolerance of rice plants to brown planthopper.

Expression Analysis of Genes Related to Rice Resistance Against Brown Planthopper, Nilaparvata lugens

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Panatda Jannoey

2017-05-01

Full Text Available Brown planthopper (BPH is an insect species that feeds on the vascular system of rice plants. To examine the defence mechanism of rice plants against BPH, the pathogenesis-related genes (PR1a, PR2, PR3, PR4, PR6, PR9, PR10a, PR13, PR15 and PRpha, signaling molecule synthesis genes (AOS, AXR, ACO and LOX, antioxidant-related genes (CAT, TRX, GST and SOD and lignin biosynthesis-related genes (CHS, CHI and C4H were investigated in a resistant rice variety. AOS, PR6, PR9 and PR15 genes showed significantly increased relative expression levels at 24.38-, 19.17-, 14.71-, and 12.74-fold compared to the control. Moderate increased relative expression levels of lignin biosynthesis-related gene (C4H, pathogenesis-related genes (PR4, PR10a and PRpha, and antioxidant-related gene (GST were found, while CHI, LOX, SOD, TRX1 and AXR showed decreased relative expression levels. It was thus clearly shown that wound-induced response genes were activated in rice plants after BPH attacks through AOS activation. Jasmonic acid signaling molecule may activate PR6, PR15, GST and CAT subsequently increasing their expression for H2O2 detoxification. PR6 were expressed at the highest relative level among the PR genes. These genes therefore have also a considerable synergistic role with the other genes against BPH by interfered their digestion tract system.

Comparison of esterase gene amplification, gene expression and esterase activity in insecticide susceptible and resistant strains of the brown planthopper, Nilaparvata lugens (Stål).

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Vontas, J G; Small, G J; Hemingway, J

2000-12-01

Organophosphorus and carbamate insecticide resistance in Nilaparvata lugens is based on amplification of a carboxylesterase gene, Nl-EST1. An identical gene occurs in susceptible insects. Quantitative real-time PCR was used to demonstrate that Nl-EST1 is amplified 3-7-fold in the genome of resistant compared to susceptible planthoppers. Expression levels were similar to amplification levels, with 1-15-fold more Nl-EST1 mRNA in individual insects and 5-11-fold more Nl-EST1 mRNA in mass whole body homogenates of resistant females compared to susceptibles. These values corresponded to an 8-10-fold increase in esterase activity in the head and thorax of individual resistant insects. Although amplification, expression and activity levels of Nl-EST1 in resistant N. lugens were similar, the correlation between esterase activity and Nl-EST1 mRNA levels in resistant individuals was not linear.

Identification of a rice gene (Bph 1) conferring resistance to brown planthopper (Nilaparvata lugens Stal) using STS markers.

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Kim, Suk-Man; Sohn, Jae-Keun

2005-08-31

This study was carried out to identify a high-resolution marker for a gene conferring resistance to brown planthopper (BPH) biotype 1, using japonica type resistant lines. Bulked segregant analyses were conducted using 520 RAPD primers to identify RAPD fragments linked to the BPH resistance gene. Eleven RAPDs were shown to be polymorphic amplicons between resistant and susceptible progeny. One of these primers, OPE 18, which amplified a 923 bp band tightly linked to resistance, was converted into a sequence-tagged-site (STS) marker. The STS marker, BpE18-3, was easily detectable as a dominant band with tight linkage (3.9cM) to Bph1. It promises to be useful as a marker for assisted selection of resistant progeny in backcross breeding programs to introgress the resistance gene into elite japonica cultivars.

The complete mitochondrial genomes of two rice planthoppers, Nilaparvata lugens and Laodelphax striatellus: conserved genome rearrangement in Delphacidae and discovery of new characteristics of atp8 and tRNA genes.

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Zhang, Kai-Jun; Zhu, Wen-Chao; Rong, Xia; Zhang, Yan-Kai; Ding, Xiu-Lei; Liu, Jing; Chen, Da-Song; Du, Yu; Hong, Xiao-Yue

2013-06-22

Nilaparvata lugens (the brown planthopper, BPH) and Laodelphax striatellus (the small brown planthopper, SBPH) are two of the most important pests of rice. Up to now, there was only one mitochondrial genome of rice planthopper has been sequenced and very few dependable information of mitochondria could be used for research on population genetics, phylogeographics and phylogenetic evolution of these pests. To get more valuable information from the mitochondria, we sequenced the complete mitochondrial genomes of BPH and SBPH. These two planthoppers were infected with two different functional Wolbachia (intracellular endosymbiont) strains (wLug and wStri). Since both mitochondria and Wolbachia are transmitted by cytoplasmic inheritance and it was difficult to separate them when purified the Wolbachia particles, concomitantly sequencing the genome of Wolbachia using next generation sequencing method, we also got nearly complete mitochondrial genome sequences of these two rice planthoppers. After gap closing, we present high quality and reliable complete mitochondrial genomes of these two planthoppers. The mitogenomes of N. lugens (BPH) and L. striatellus (SBPH) are 17, 619 bp and 16, 431 bp long with A + T contents of 76.95% and 77.17%, respectively. Both species have typical circular mitochondrial genomes that encode the complete set of 37 genes which are usually found in metazoans. However, the BPH mitogenome also possesses two additional copies of the trnC gene. In both mitochondrial genomes, the lengths of the atp8 gene were conspicuously shorter than that of all other known insect mitochondrial genomes (99 bp for BPH, 102 bp for SBPH). That two rearrangement regions (trnC-trnW and nad6-trnP-trnT) of mitochondrial genomes differing from other known insect were found in these two distantly related planthoppers revealed that the gene order of mitochondria might be conservative in Delphacidae. The large non-coding fragment (the A+T-rich region) putatively

Impact of Abamectin on Anagrus nilaparvatae, An Egg Parasitoid of Nilaparvata lugens

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Edi Eko Sasmito

2017-12-01

Full Text Available Anagrus nilaparvatae (Hymenoptera: Mymaridae is an egg parasitoid potential for controlling the major pests on rice, the brown planthopper (Nilaparvata lugens [Hemiptera: Delphacidae].Abamectin is one of insecticides registered for N. lugens. The research was aimed to investigate the impact of contact application of abamectin on the parasitism level of A. nilaparvatae under laboratory conditions. Adults of A. nilaparvatae and the first instars as well as adults of N. lugens were exposed to the residue of abamection inside the test tube. A. nilaparvatae was much more susceptible to abamectin compared to N. lugens. Application of abamectin at the recommended concentration (22.78 ppm for 30 min caused 100% mortality, and it reduced to 85% when the concentration was decreased to 0.36 ppm. In contrast, the mortality for the first instar of N. lugens was only 15% at 22.78 and no mortality at 0.36 ppm. No N. lugens adults died even when they were exposed to 22.78 ppm. Furthermore, the parasitism test was conducted using 38 days after planting of IR-64 rice variety. Those plants were infested with 50 females of N. lugens for 2 days. A. nilaparvatae were exposed by contact to 0.02, 0.23, and 2.28 ppm of abamectin. The survivors were released to the rice plant containing eggs of N. lugens. Contact application of abamectin reduced parasitism level of A. nilaparvatae as much as 86.34, 70.01, and 28.43% with concentrations of 2.28 ppm, 0.23 and 0.02 ppm, respectively. In addition, the number of parasitoids emerged decreased with increasing concentration of abamectin. These results suggest that abamectin could be detrimental to A. nilaparvatae due to direct mortality, reduced the parasitism level, and decreased the number of progeny produced.   Intisari Anagrus nilaparvatae (Hymenoptera: Mymaridae merupakan salah satu parasitoid telur yang berpotensi untuk mengendalikan hama utama tanaman padi, wereng batang padi cokelat (Nilaparvata lugens [Hemiptera

Evaluasi Sifat Ovisidal dan Nimfasidal Insektisida Buprofezin 100 g/l terhadap Telur dan Nimfa Wereng Coklat, Nilaparvata lugens (Stal.) (Hemiptera: Delphacidae)

OpenAIRE

BAEHAKI SUHERLAN EFFENDI; EKO HARI ISWANTO; AMIR HAMZAH

2016-01-01

Evaluation of ovicidal and nymphcidal properties of buprofezin 100 g/linsecticide to eggs and nymphs of brown planthopper, Nilaparvata lugens(Stal.) (Hemiptera: Delphacidae). Research was carried out in screen house ofSukamandi, Indonesian Center for Rice Research (ICRR) in the wet season of 2013. Theresearch used randomized block design with 5 doses levels insecticide treatment of buprofezin100 g/l and four replications. The buprofezin treatments were 250, 500, 750, 1000, and 1500ml/ha compa...

Functional analysis of CYP6ER1, a P450 gene associated with imidacloprid resistance in Nilaparvata lugens

OpenAIRE

Pang, Rui; Chen, Meng; Liang, Zhikun; Yue, Xiangzhao; Ge, Hu; Zhang, Wenqing

2016-01-01

The cytochrome P450 CYP6ER1 has been reported to play an important role in imidacloprid resistance of the brown planthopper (BPH), Nilaparvata lugens, and is overexpressed in most resistant populations. In the present study, we confirmed that CYP6ER1 expression can be induced by certain levels of imidacloprid. Developmental expression analysis revealed that CYP6ER1 was expressed highly in the adult stage, and tissue distribution analysis showed that CYP6ER1 was expressed mainly in the fat bod...

Mapping and marker-assisted selection of a brown planthopper resistance gene bph2 in rice (Oryza sativa L.).

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Sun, Li-Hong; Wang, Chun-Ming; Su, Chang-Chao; Liu, Yu-Qiang; Zhai, Hu-Qu; Wan, Jian-Min

2006-08-01

Nilaparvata lugens Stål (brown planthopper, BPH), is one of the major insect pests of rice (Oryza sativa L.) in the temperate rice-growing region. In this study, ASD7 harboring a BPH resistance gene bph2 was crossed to a susceptible cultivar C418, a japonica restorer line. BPH resistance was evaluated using 134 F2:3 lines derived from the cross between "ASD7" and "C418". SSR assay and linkage analysis were carried out to detect bph2. As a result, the resistant gene bph2 in ASD7 was successfully mapped between RM7102 and RM463 on the long arm of chromosome 12, with distances of 7.6 cM and 7.2 cM, respectively. Meanwhile, both phenotypic selection and marker-assisted selection (MAS) were conducted in the BC1F1 and BC2F1 populations. Selection efficiencies of RM7102 and RM463 were determined to be 89.9% and 91.2%, respectively. It would be very beneficial for BPH resistance improvement by using MAS of this gene.

RFLP-facilitated investigation of the quantitative resistance of rice to brown planthopper ( Nilaparvata lugens).

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Xu, X. F.; Mei, H. W.; Luo, L. J.; Cheng, X. N.; Li, Z. K.

2002-02-01

Quantitative trait loci (QTLs), conferring quantitative resistance to rice brown planthopper (BPH), were investigated using 160 F(11) recombinant inbred lines (RILs) from the Lemont/Teqing cross, a complete RFLP map, and replicated phenotyping of seedbox inoculation. The paternal indica parent, Teqing, was more-resistant to BPH than the maternal japonica parent, Lemont. The RILs showed transgressive segregation for resistance to BPH. Seven main-effect QTLs and many epistatic QTL pairs were identified and mapped on the 12 rice chromosomes. Collectively, the main-effect and epistatic QTLs accounted for over 70% of the total variation in damage scores. Teqing has the resistance allele at four main-effect QTLs, and the Lemont allele resulted in resistance at the other three. Of the main-effect QTLs identified, QBphr5b was mapped to the vicinity of gl1, a major gene controlling leaf and stem pubescence. The Teqing allele controlling leaf and stem pubescence was associated with resistance, while the Lemont allele for glabrous stem and leaves was associated with susceptibility, indicating that this gene may have contributed to resistance through antixenosis. Similar to the reported BPH resistance genes, the other six detected main-effect QTLs were all mapped to regions where major disease resistance genes locate, suggesting they might have contributed either to antibiosis or tolerance. Our results indicated that marker-aided pyramiding of major resistance genes and QTLs should provide effective and stable control over this devastating pest.

Rice mutation breeding for resistance against leaf blight disease and brown planthopper

International Nuclear Information System (INIS)

Mugiono; Ismachin, M

1981-01-01

Seeds of Pelita 1/1 were treated variously with EMS 1%, 20, 30, 35, 40 and 50 krad doses gamma rays from a Co 60 source. The 1% EMS treatment, of presoaking for 36 hours in distilled water and stored for one week before sowing, yielded more mutants resistant against bacterial leaf blight compared to other treatments with EMS. Treatment with 20 krad of gamma rays gave an indication of a good probability for improving resistance. Screening for brown planthopper resistance among 350 M 4 lines yielded 4 moderate resistant (MR) lines. However, no resistant line was found. From 36 crosses between the mutants and IR-26 or mutants with Mudgo 86 promising lines were found. The promising lines, beside resistant against brown planthopper, were selected based on early maturity and short stem. (author)

Genetic Analysis and Preliminary Mapping of Two Recessive Resistance Genes to Brown Planthopper, Nilaparvata lugens Stål in Rice

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Li-yuan HOU

2011-09-01

Full Text Available An F2 population derived from the cross of WB01, an introgression line resistant to brown planthopper (BPH originated from Oryza rufipogon Griff. and a susceptible indica variety 9311, was developed for genetic analysis and gene mapping. The population with 303 F2:3 families was genotyped by 141 simple sequence repeat (SSR markers and used for gene mapping. Two softwares, Mapmaker/Exp 3.0 and Windows QTL Cartographer V2.0 were applied to detect QTLs. Totally, two QTLs resistant to BPH, named temporarily as bph22(t and bph23(t, were identified to locate on chromosomes 4 and 8, individually had LOD values of 2.92 and 3.15, and explained 11.3% and 14 .9% of the phenotypic variation, respectively.

Selection and evaluation of potential reference genes for gene expression analysis in the brown planthopper, Nilaparvata lugens (Hemiptera: Delphacidae using reverse-transcription quantitative PCR.

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Miao Yuan

Full Text Available The brown planthopper (BPH, Nilaparvata lugens (Hemiptera, Delphacidae, is one of the most important rice pests. Abundant genetic studies on BPH have been conducted using reverse-transcription quantitative real-time PCR (qRT-PCR. Using qRT-PCR, the expression levels of target genes are calculated on the basis of endogenous controls. These genes need to be appropriately selected by experimentally assessing whether they are stably expressed under different conditions. However, such studies on potential reference genes in N. lugens are lacking. In this paper, we presented a systematic exploration of eight candidate reference genes in N. lugens, namely, actin 1 (ACT, muscle actin (MACT, ribosomal protein S11 (RPS11, ribosomal protein S15e (RPS15, alpha 2-tubulin (TUB, elongation factor 1 delta (EF, 18S ribosomal RNA (18S, and arginine kinase (AK and used four alternative methods (BestKeeper, geNorm, NormFinder, and the delta Ct method to evaluate the suitability of these genes as endogenous controls. We examined their expression levels among different experimental factors (developmental stage, body part, geographic population, temperature variation, pesticide exposure, diet change, and starvation following the MIQE (Minimum Information for publication of Quantitative real time PCR Experiments guidelines. Based on the results of RefFinder, which integrates four currently available major software programs to compare and rank the tested candidate reference genes, RPS15, RPS11, and TUB were found to be the most suitable reference genes in different developmental stages, body parts, and geographic populations, respectively. RPS15 was the most suitable gene under different temperature and diet conditions, while RPS11 was the most suitable gene under different pesticide exposure and starvation conditions. This work sheds light on establishing a standardized qRT-PCR procedure in N. lugens, and serves as a starting point for screening for reference genes for

Pengaruh insektisida deltametrin terhadap perilaku orientasi parasitoid Anagrus nilaparvatae (Pang et Wang (Hymenoptera: Mymaridae

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Araz Meilin

2016-09-01

Full Text Available Host searching behaviour by a parasitoid includes orientation to the volatile compounds (odor relesead by host or host plant. The aim of this study was to determine the changes in the orientation behaviour of Anagrus nilaparvatae (Pang et Wang, the egg parasitoid of rice brown planthoppers (Nilaparvata lugens (Stål, after being exposed to sublethal concentrations of deltamethrin. The impact of residue on plants to the behaviour of parasitoid was also studied. The sublethal concentrations (LC10 and LC40 used were 0.023 ppm and 2.235 ppm, respectively. Deltamethrin applied to the rice plants were 12.5 ppm and 6.25 ppm, and its effect was observed at 3 hours, 1, 3 and 7 days after application. Orientation behavior was studied using Y-tube olfactometer. Application of deltamethrin at subletal concentration reduced the ability of surviving A. nilaparvatae to detect odors (volatile ompounds released by the host, N. lugens. The higher the concentration of deltamethrin applied to the parasitoid or to the rice plants, the more prominent effect observed in the changing in the parasitoid behavious, in particular disruption to the parasitoid’s orientation to find their host. As consequences, effects of deltamethrin may lead to reduce the effectiveness of A. nilaparvatae as biological control agents in the field as a result of declining their searching capacity. 

Glycogen Phosphorylase and Glycogen Synthase: Gene Cloning and Expression Analysis Reveal Their Role in Trehalose Metabolism in the Brown Planthopper, Nilaparvata lugens Stål (Hemiptera: Delphacidae).

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Zhang, Lu; Wang, Huijuan; Chen, Jianyi; Shen, Qida; Wang, Shigui; Xu, Hongxing; Tang, Bin

2017-01-01

RNA interference has been used to study insects' gene function and regulation. Glycogen synthase (GS) and glycogen phosphorylase (GP) are two key enzymes in carbohydrates' conversion in insects. Glycogen content and GP and GS gene expression in several tissues and developmental stages of the Brown planthopper Nilaparvata lugens Stål (Hemiptera: Delphacidae) were analyzed in the present study, using quantitative reverse-transcription polymerase chain reaction to determine their response to double-stranded trehalases (dsTREs), trehalose-6-phosphate synthases (dsTPSs), and validamycin injection. The highest expression of both genes was detected in the wing bud, followed by leg and head tissues, and different expression patterns were shown across the developmental stages analyzed. Glycogen content significantly decreased 48 and 72 h after dsTPSs injection and 48 h after dsTREs injection. GP expression increased 48 h after dsTREs and dsTPSs injection and significantly decreased 72 h after dsTPSs, dsTRE1-1, and dsTRE1-2 injection. GS expression significantly decreased 48 h after dsTPS2 and dsTRE2 injection and 72 h after dsTRE1-1 and dsTRE1-2 injection. GP and GS expression and glycogen content significantly decreased 48 h after validamycin injection. The GP activity significantly decreased 48 h after validamycin injection, while GS activities of dsTPS1 and dsTRE2 injection groups were significantly higher than that of double-stranded GFP (dsGFP) 48 h after injection, respectively. Thus, glycogen is synthesized, released, and degraded across several insect tissues according to the need to maintain stable trehalose levels. © The Authors 2017. Published by Oxford University Press on behalf of Entomological Society of America.

Video monitoring of brown planthopper predation in rice shows flaws of sentinel methods

NARCIS (Netherlands)

Zou, Yi; Kraker, De Joop; Bianchi, Felix J.J.A.; Telgen, Van Mario D.; Xiao, Haijun; Werf, Van Der Wopke

2017-01-01

Immobilized preys are routinely used in agro-ecological exposure studies to quantify predation of pests under field conditions, but this method has not been validated. Our purpose was to determine the validity of using immobilized adults of the major rice pest Nilaparvata lugens, brown plant hopper

Study on the Effect of Wing Bud Chitin Metabolism and Its Developmental Network Genes in the Brown Planthopper, Nilaparvata lugens, by Knockdown of TRE Gene

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Lu Zhang

2017-09-01

Full Text Available The brown planthopper, Nilaparvata lugens is one of the most serious pests of rice, and there is so far no effective way to manage this pest. However, RNA interference not only can be used to study gene function, but also provide potential opportunities for novel pest management. The development of wing plays a key role in insect physiological activities and mainly involves chitin. Hence, the regulating role of trehalase (TRE genes on wing bud formation has been studied by RNAi. In this paper, the activity levels of TRE and the contents of the two sugars trehalose and glucose were negatively correlated indicating the potential role of TRE in the molting process. In addition, NlTRE1-1 and NlTRE2 were expressed at higher levels in wing bud tissue than in other tissues, and abnormal molting and wing deformity or curling were noted 48 h after the insect was injected with any double-stranded TRE (dsTRE, even though different TREs have compensatory functions. The expression levels of NlCHS1b, NlCht1, NlCht2, NlCht6, NlCht7, NlCht8, NlCht10, NlIDGF, and NlENGase decreased significantly 48 h after the insect was injected with a mixture of three kinds of dsTREs. Similarly, the TRE inhibitor validamycin can inhibit NlCHS1 and NlCht gene expression. However, the wing deformity was the result of the NlIDGF, NlENGase, NlAP, and NlTSH genes being inhibited when a single dsTRE was injected. These results demonstrate that silencing of TRE gene expression can lead to wing deformities due to the down-regulation of the AP and TSH genes involved in wing development and that the TRE inhibitor validamycin can co-regulate chitin metabolism and the expression of wing development-related genes in wing bud tissue. The results provide a new approach for the prevention and management of N. lugens.

Study on the Effect of Wing Bud Chitin Metabolism and Its Developmental Network Genes in the Brown Planthopper, Nilaparvata lugens, by Knockdown of TRE Gene.

Science.gov (United States)

Zhang, Lu; Qiu, Ling-Yu; Yang, Hui-Li; Wang, Hui-Juan; Zhou, Min; Wang, Shi-Gui; Tang, Bin

2017-01-01

The brown planthopper, Nilaparvata lugens is one of the most serious pests of rice, and there is so far no effective way to manage this pest. However, RNA interference not only can be used to study gene function, but also provide potential opportunities for novel pest management. The development of wing plays a key role in insect physiological activities and mainly involves chitin. Hence, the regulating role of trehalase (TRE) genes on wing bud formation has been studied by RNAi. In this paper, the activity levels of TRE and the contents of the two sugars trehalose and glucose were negatively correlated indicating the potential role of TRE in the molting process. In addition, NlTRE1-1 and NlTRE2 were expressed at higher levels in wing bud tissue than in other tissues, and abnormal molting and wing deformity or curling were noted 48 h after the insect was injected with any double-stranded TRE ( dsTRE ), even though different TREs have compensatory functions. The expression levels of NlCHS1b, NlCht1, NlCht2, NlCht6, NlCht7, NlCht8, NlCht10, NlIDGF , and NlENGase decreased significantly 48 h after the insect was injected with a mixture of three kinds of dsTREs . Similarly, the TRE inhibitor validamycin can inhibit NlCHS1 and NlCht gene expression. However, the wing deformity was the result of the NlIDGF, NlENGase, NlAP , and NlTSH genes being inhibited when a single dsTRE was injected. These results demonstrate that silencing of TRE gene expression can lead to wing deformities due to the down-regulation of the AP and TSH genes involved in wing development and that the TRE inhibitor validamycin can co-regulate chitin metabolism and the expression of wing development-related genes in wing bud tissue. The results provide a new approach for the prevention and management of N. lugens .

Phloem-exudate proteome analysis of response to insect brown plant-hopper in rice.

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Du, Ba; Wei, Zhe; Wang, Zhanqi; Wang, Xiaoxiao; Peng, Xinxin; Du, Bo; Chen, Rongzhi; Zhu, Lili; He, Guangcun

2015-07-01

Brown plant-hopper (Nilaparvata lugens Stål, BPH), one of the most devastating agricultural insect pests of rice throughout Asia, ingests nutrients from rice sieve tubes and causes a dramatic yield loss. Planting resistant variety is an efficient and economical way to control this pest. Understanding the mechanisms of host resistance is extremely valuable for molecular design of resistant rice variety. Here, we used an iTRAQ-based quantitative proteomics approach to perform analysis of protein expression profiles in the phloem exudates of BPH-resistant and susceptible rice plants following BPH infestation. A total of 238 proteins were identified, most of which were previously described to be present in the phloem of rice and other plants. The expression of genes for selected proteins was confirmed using a laser capture micro-dissection method and RT-PCR. The mRNAs for three proteins, RGAP, TCTP, and TRXH, were further analyzed by using in situ mRNA hybridization and localized in the phloem cells. Our results showed that BPH feeding induced significant changes in the abundance of proteins in phloem sap of rice involved in multiple pathways, including defense signal transduction, redox regulation, and carbohydrate and protein metabolism, as well as cell structural proteins. The results presented provide new insights into rice resistance mechanisms and should facilitate the breeding of novel elite BPH-resistant rice varieties. Copyright © 2015 Elsevier GmbH. All rights reserved.

The Bphi008a gene interacts with the ethylene pathway and transcriptionally regulates MAPK genes in the response of rice to brown planthopper feeding.

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Hu, Jing; Zhou, Jiangbo; Peng, Xinxin; Xu, Henghao; Liu, Caixiang; Du, Bo; Yuan, Hongyu; Zhu, Lili; He, Guangcun

2011-06-01

We examined ways in which the Brown planthopper induced008a (Bphi008a; AY256682) gene of rice (Oryza sativa) enhances the plant's resistance to a specialist herbivore, the brown planthopper (BPH; Nilaparvata lugens). Measurement of the expression levels of ethylene synthases and of ethylene emissions showed that BPH feeding rapidly initiated the ethylene signaling pathway and up-regulated Bphi008a transcript levels after 6 to 96 h of feeding. In contrast, blocking ethylene transduction (using 1-methylcyclopropene) reduced Bphi008a transcript levels in wild-type plants fed upon by BPH. In vitro kinase assays showed that Bphi008a can be phosphorylated by rice Mitogen-activated Protein Kinase5 (OsMPK5), and yeast two-hybrid assays demonstrated that the carboxyl-terminal proline-rich region of Bphi008a interacts directly with this kinase. Furthermore, bimolecular fluorescence complementation assays showed that this interaction occurs in the nucleus. Subsequently, we found that Bphi008a up-regulation and down-regulation were accompanied by different changes in transcription levels of OsMPK5, OsMPK12, OsMPK13, and OsMPK17 in transgenic plants. Immunoblot analysis also showed that the OsMPK5 protein level increased in overexpressing plants and decreased in RNA interference plants after BPH feeding. In transgenic lines, changes in the expression levels of several enzymes that are important components of the defenses against the BPH were also observed. Finally, yeast two-hybrid screening results showed that Bphi008a is able to interact with a b-ZIP transcription factor (OsbZIP60) and a RNA polymerase polypeptide (SDRP).

Evolving ideas about genetics underlying insect virulence to plant resistance in rice-brown planthopper interactions.

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Kobayashi, Tetsuya

2016-01-01

Many plant-parasite interactions that include major plant resistance genes have subsequently been shown to exhibit features of gene-for-gene interactions between plant Resistance genes and parasite Avirulence genes. The brown planthopper (BPH) Nilaparvata lugens is an important pest of rice (Oryza sativa). Historically, major Resistance genes have played an important role in agriculture. As is common in gene-for-gene interactions, evolution of BPH virulence compromises the effectiveness of singly-deployed resistance genes. It is therefore surprising that laboratory studies of BPH have supported the conclusion that virulence is conferred by changes in many genes rather than a change in a single gene, as is proposed by the gene-for-gene model. Here we review the behaviour, physiology and genetics of the BPH in the context of host plant resistance. A problem for genetic understanding has been the use of various insect populations that differ in frequencies of virulent genotypes. We show that the previously proposed polygenic inheritance of BPH virulence can be explained by the heterogeneity of parental populations. Genetic mapping of Avirulence genes indicates that virulence is a monogenic trait. These evolving concepts, which have brought the gene-for-gene model back into the picture, are accelerating our understanding of rice-BPH interactions at the molecular level. Copyright © 2015 Elsevier Ltd. All rights reserved.

Identification of a new locus conferring antixenosis to the brown planthopper in rice cultivar Swarnalata (Oryza sativa L.).

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Qiu, Y F; Cheng, L; Liu, F; Li, R B

2013-08-29

The brown planthopper [Nilaparvata lugens (Stål); BPH] has caused severe damage to rice production. The identification of resistance genes and the development of BPH-resistant varieties are economical and effective ways to manage this pest. Using an F2 population from a cross between the Indica cultivars 93-11 and Swarnalata, we mapped the Qbph-8 locus to a 7.3-cM region on chromosome 8 in two tests, flanked by the markers RM339 and RM515. In this population, Qbph-8 explained 7.7 and 6.6% of the phenotypic variance of BPH preference in both tests. In the BPH host choice test, the average number of settled BPHs on the Qbph-8 plants was less than that on the 93-11 plants over the 24- to 120-h observation period. Furthermore, less BPH insects were observed on the BPH6+Qbph-8 plant compared with the BPH6 plant or Qbph-8 plant, indicating a stronger antixenotic effect shown in the gene pyramiding plants. Hence, this locus can be pyramided with other BPH resistance genes and applied to breed-resistant varieties, which possibly can improve the resistance level and durable resistance to the BPH.

Molecular tagging of the Bph1 locus for resistance to brown planthopper (Nilaparvata lugens Stål) through representational difference analysis.

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Park, Dong-Soo; Song, Min-Young; Park, Soo-Kwon; Lee, Sang-Kyu; Lee, Jong-Hee; Song, Song-Yi; Eun, Moo Young; Hahn, Tae-Ryong; Sohn, Jae-Keun; Yi, Gihwan; Nam, Min-Hee; Jeon, Jong-Seong

2008-08-01

During brown planthopper (BPH) feeding on rice plants, we employed a modified representational difference analysis (RDA) method to detect rare transcripts among those differentially expressed in SNBC61, a BPH resistant near-isogenic line (NIL) carrying the Bph1 resistance gene. This identified 3 RDA clones: OsBphi237, OsBphi252 and OsBphi262. DNA gel-blot analysis revealed that the loci of the RDA clones in SNBC61 corresponded to the alleles of the BPH resistant donor Samgangbyeo. Expression analysis indicated that the RDA genes were up-regulated in SNBC61 during BPH feeding. Interestingly, analysis of 64 SNBC NILs, derived from backcrosses of Samgangbyeo with a BPH susceptible Nagdongbyeo, using a cleaved amplified polymorphic sequence (CAPS) marker indicated that OsBphi252, which encodes a putative lipoxygenase (LOX), co-segregates with BPH resistance. Our results suggest that OsBphi252 is tightly linked to Bph1, and may be useful in marker-assisted selection (MAS) for resistance to BPH.

Uptake of 14C-carbofuran from rice plants by brown planthopper (nilaparvata lugens stal) and green leafhopper (Nephotettix virencence)

International Nuclear Information System (INIS)

Sumatra, M.; Anwar, E.; Kuswadi, A.N.; Soekarna, D.

1988-01-01

An experiment was carried out to determine the amount of 14-C-carbofuran taken up by brown planthopper (BPH) and green leafhopper (GLH) from ride plants containing 14-C-carbofuran. The roots of 30 days old rice plants were immersed in Kimura B solution containing carbofuran (0.6ug/ml) with activity of 18600 pCi/ml. After 3 days, 20 BPH and 20 GLH released onto the rice stems and leaves. The mortalities of BPH and GLH were similar after 24 and 48 hours of the release. The average radioactivity found in living GLH was 3.5 times of those found in living GLH was 3.5 times of those found in living BPH. And in dead GLH was 3.2 times on those in dead BPH. Radioactivity in rice leaves was 3.5 times of those in stems. This layer chromatograph of extracts of Kimura B solution, stems, and leaves showed that small amounts of carbofuran had degraded to substances like 3-OH-carbofuran and 3-keto-carbofuran. The percentage of radioactivity found as carbofuran decreased with time, while the amount of 3-ket-carbofuran increased. (authors). 6 refs, 2 figs, 6 tab

Map-based Cloning and Characterization of a Brown Planthopper Resistance Gene BPH26 from Oryza sativa L. ssp. indica Cultivar ADR52

OpenAIRE

Tamura, Yasumori; Hattori, Makoto; Yoshioka, Hirofumi; Yoshioka, Miki; Takahashi, Akira; Wu, Jianzhong; Sentoku, Naoki; Yasui, Hideshi

2014-01-01

The brown planthopper (BPH) is the most serious insect pest of rice in Asia. The indica rice cultivar ADR52 carries two BPH resistance genes, BPH26 (BROWN PLANTHOPPER RESISTANCE 26) and BPH25. Map-based cloning of BPH26 revealed that BPH26 encodes a coiled-coil-nucleotide-binding-site?leucine-rich repeat (CC?NBS?LRR) protein. BPH26 mediated sucking inhibition in the phloem sieve element. BPH26 was identical to BPH2 on the basis of DNA sequence analysis and feeding ability of the BPH2-virulent...

Identification of SNPs involved in regulating a novel alternative transcript of P450 CYP6ER1 in the brown planthopper.

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Liang, Zhi-Kun; Pang, Rui; Dong, Yi; Sun, Zhong-Xiang; Ling, Yan; Zhang, Wen-Qing

2017-04-29

Cytochrome P450-mediated metabolic resistance is one of the major mechanisms involved in insecticide resistance. Although the up-regulation of cytochrome P450 plays a vital role in insecticide metabolism, the molecular basis for the transcriptional regulation of cytochrome P450 remains largely unknown. The P450 gene CYP6ER1, has been reported to confer imidacloprid resistance to the brown planthopper, Nilaparvata lugens. Here, we identified a novel alternative transcript of CYP6ER1 (transcript A2) that had different expression patterns between resistant and susceptible populations, and was more stable after insecticide induction. The promoter of this transcript was sequenced and multiple single nucleotide polymorphisms (SNPs) were detected in individuals from susceptible and resistant field-collected populations. Resistant alleles of four SNPs were found to significantly enhance the promoter activity of the CYP6ER1 transcript A2. Electrophoretic mobility shift assays (EMSAs) revealed that these SNPs might regulate the binding of transcription factors to the promoter. Our findings provide novel evidence regarding the transcriptional regulation of a metabolic resistance-related gene and may be useful to understand the resistance mechanism of N. lugens in the field. © 2017 Institute of Zoology, Chinese Academy of Sciences.

Two fungicides alter reproduction of the small brown planthopper, Laodelphax striatellus by influencing gene and protein expression

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Aside from their intended actions, fungicides can drive pest insect outbreaks and, due to virtually continuous use, evolution. Small brown planthopper (SBPH), Laodelphax striatellus, outbreaks occurred recently in many provinces in China, with devastating rice losses. Because exposure to the fungici...

Pyramiding and evaluation of three dominant brown planthopper resistance genes in the elite indica rice 9311 and its hybrids.

Science.gov (United States)

Hu, Jie; Cheng, Mingxing; Gao, Guanjun; Zhang, Qinglu; Xiao, Jinghua; He, Yuqing

2013-07-01

Brown planthopper (BPH), Nilaparvata lugens Stål, is the most devastating insect pest in rice-producing areas. Three dominant BPH resistance genes (Bph14, Bph15, Bph18) were pyramided into elite indica rice 9311 and its hybrids using marker-assisted selection. Gene effectiveness was evaluated on the basis of seedling and adult rice resistance, honeydew weight and survival rate of BPH. All three genes affected BPH growth and development and antibiotic factors, resulting in both seedling and adult resistance. Bph15 had the greatest effect on conferring resistance to BPH. The results showed an additive effect of pyramiding genes, the order of the gene effect being 14/15/18 ≥ 14/15 > 15/18 ≥ 15 > 14/18 ≥ 14 ≥ 18 > none. The pyramided or single-gene introgression hybrids showed greater resistance than conventional hybrids, although the heterozygous genotypes had weaker effects than the corresponding homozygous genotypes. Furthermore, field trial data demonstrated that yields of improved 9311 lines were higher than or similar to that of the control under natural field conditions. These improved versions can be immediately used in hybrid improvement and production. Compared with controls, pyramided lines and hybrids with three genes showed the strongest resistance to BPH, without a yield decrease. © 2012 Society of Chemical Industry.

Bph32, a novel gene encoding an unknown SCR domain-containing protein, confers resistance against the brown planthopper in rice

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Ren, Juansheng; Gao, Fangyuan; Wu, Xianting; Lu, Xianjun; Zeng, Lihua; Lv, Jianqun; Su, Xiangwen; Luo, Hong; Ren, Guangjun

2016-01-01

An urgent need exists to identify more brown planthopper (Nilaparvata lugens Stål, BPH) resistance genes, which will allow the development of rice varieties with resistance to BPH to counteract the increased incidence of this pest species. Here, using bioinformatics and DNA sequencing approaches, we identified a novel BPH resistance gene, LOC_Os06g03240 (MSU LOCUS ID), from the rice variety Ptb33 in the interval between the markers RM19291 and RM8072 on the short arm of chromosome 6, where a gene for resistance to BPH was mapped by Jirapong Jairin et al. and renamed as “Bph32”. This gene encodes a unique short consensus repeat (SCR) domain protein. Sequence comparison revealed that the Bph32 gene shares 100% sequence identity with its allele in Oryza latifolia. The transgenic introgression of Bph32 into a susceptible rice variety significantly improved resistance to BPH. Expression analysis revealed that Bph32 was highly expressed in the leaf sheaths, where BPH primarily settles and feeds, at 2 and 24 h after BPH infestation, suggesting that Bph32 may inhibit feeding in BPH. Western blotting revealed the presence of Pph (Ptb33) and Tph (TN1) proteins using a Penta-His antibody, and both proteins were insoluble. This study provides information regarding a valuable gene for rice defence against insect pests. PMID:27876888

Bph32, a novel gene encoding an unknown SCR domain-containing protein, confers resistance against the brown planthopper in rice.

Science.gov (United States)

Ren, Juansheng; Gao, Fangyuan; Wu, Xianting; Lu, Xianjun; Zeng, Lihua; Lv, Jianqun; Su, Xiangwen; Luo, Hong; Ren, Guangjun

2016-11-23

An urgent need exists to identify more brown planthopper (Nilaparvata lugens Stål, BPH) resistance genes, which will allow the development of rice varieties with resistance to BPH to counteract the increased incidence of this pest species. Here, using bioinformatics and DNA sequencing approaches, we identified a novel BPH resistance gene, LOC_Os06g03240 (MSU LOCUS ID), from the rice variety Ptb33 in the interval between the markers RM19291 and RM8072 on the short arm of chromosome 6, where a gene for resistance to BPH was mapped by Jirapong Jairin et al. and renamed as "Bph32". This gene encodes a unique short consensus repeat (SCR) domain protein. Sequence comparison revealed that the Bph32 gene shares 100% sequence identity with its allele in Oryza latifolia. The transgenic introgression of Bph32 into a susceptible rice variety significantly improved resistance to BPH. Expression analysis revealed that Bph32 was highly expressed in the leaf sheaths, where BPH primarily settles and feeds, at 2 and 24 h after BPH infestation, suggesting that Bph32 may inhibit feeding in BPH. Western blotting revealed the presence of Pph (Ptb33) and Tph (TN1) proteins using a Penta-His antibody, and both proteins were insoluble. This study provides information regarding a valuable gene for rice defence against insect pests.

Parasitism of The Rice Brown Planthopper Eggs in Various Periods of Time of The Day

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Siti Haryati

2016-07-01

Full Text Available The rice brown planthopper, Nilaparvata lugens (Hemiptera: Delphacidae is an important pest of rice. Since at the early stage, this pest is infested by parasitoids, but most cultural practices do not consider the existences of parasitoids in rice ecosystem. This study was aimed to determine the level of parasitism on N. lugens with regard to the time of the day. This information would be useful to minimize the effect of insecticide application to the parasitoids. Trapping  of  egg parasitoids in rice ecosystem was conducted every two hours from 05.00 a.m. until 04.00 p.m. Parasitism occured as early as at 05.00 a.m. (12.26% of the total parasitoid found, reached the peak abundance at 11.00 a.m. (36.13%, and decreased at 01.00 p.m. The parasitism level varied from 1.12 to 8.51% at 66 days after planting. The highest number of parasitoids and the highest parasitism level occured when trapping was conducted between 11.00 a.m.−01.00 p.m.. Before and after this period of time, the number of parasitoid emerged and parasitism were low. This suggest that if insecticide is necessary, it should be applied in the early morning or late afternoon.   INTISARI Wereng batang padi cokelat, Nilaparvata lugens (Hemiptera: Delphacidae, merupakan salah satu hama penting padi. Praktik budidaya pertanian padi belum memperhatikan aktivitas parasitoid dalam ekosistem. Tujuan dari penelitian ini yaitu untuk mengetahui tingkat parasitasi telur N. lugens pada beberapa waktu dalam sehari. Informasi ini akan bermanfaat untuk mengurangi dampak aplikasi insektisida terhadap parasitoid. Pemerangkapan parasitoid telur N. lugens di lahan padi dilakukan setiap dua jam yang dimulai pada pukul 05.00 sampai pukul 16.00. Parasitoid telur N. lugens mulai aktif pada pukul 05.00 (12,26%, mencapai puncaknya pukul 11.00 (36,13%, dan mulai mengalami penurunan pada pukul 13.00. Tingkat parasitasi pada tanaman padi umur 66 hari setelah tanam berkisar mulai 1,12−8,51%. Hasil

Role of hydroperoxide lyase in white-backed planthopper (Sogatella furcifera Horváth)-induced resistance to bacterial blight in rice, Oryza sativa L.

Science.gov (United States)

Gomi, Kenji; Satoh, Masaru; Ozawa, Rika; Shinonaga, Yumi; Sanada, Sachiyo; Sasaki, Katsutomo; Matsumura, Masaya; Ohashi, Yuko; Kanno, Hiroo; Akimitsu, Kazuya; Takabayashi, Junji

2010-01-01

A pre-infestation of the white-backed planthopper (WBPH), Sogatella furcifera Horváth, conferred resistance to bacterial blight caused by Xanthomonas oryzae pv. oryzae (Xoo) in rice (Oryza sativa L.) under both laboratory and field conditions. The infestation of another planthopper species, the brown planthopper (BPH) Nilaparvata lugens Stål, did not significantly reduce the incidence of bacterial blight symptoms. A large-scale screening using a rice DNA microarray and quantitative RT-PCR revealed that WBPH infestation caused the upregulation of more defence-related genes than did BPH infestation. Hydroperoxide lyase 2 (OsHPL2), an enzyme for producing C(6) volatiles, was upregulated by WBPH infestation, but not by BPH infestation. One C(6) volatile, (E)-2-hexenal, accumulated in rice after WBPH infestation, but not after BPH infestation. A direct application of (E)-2-hexenal to a liquid culture of Xoo inhibited the growth of the bacterium. Furthermore, a vapour treatment of rice plants with (E)-2-hexenal induced resistance to bacterial blight. OsHPL2-overexpressing transgenic rice plants exhibited increased resistance to bacterial blight. Based on these data, we conclude that OsHPL2 and its derived (E)-2-hexenal play some role in WBPH-induced resistance in rice.

Southern rice black-streaked dwarf virus: a white-backed planthopper transmitted fijivirus threadening rice production in Asia

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Guohui eZhou

2013-09-01

Full Text Available Southern rice black-streaked dwarf virus (SRBSDV, a nonenveloped icosahedral virus with a genome of 10 double-stranded RNA segments, is a novel species in the genus Fijivirus (family Reoviridae first recognized in 2008. Rice plants infected with this virus exhibit symptoms similar to those caused by Rice black-streaked dwarf virus. Since 2009, the virus has rapidly spread and caused serious rice losses in East and Southeast Asia. Significant progress has been made in recent years in understanding this disease, especially about the functions of the viral genes, rice–virus–insect interactions, and epidemiology and control measures. The virus can be efficiently transmitted by the white-backed planthopper (WBPH, Sogatella furcifera in a persistent circulative propagative manner but cannot be transmitted by the brown planthopper (Nilaparvata lugens and small brown planthopper (Laodelphax striatellus. Rice, maize, Chinese sorghum (Coix lacryma-jobi and other grass weeds can be infected via WBPH. However, only rice plays a major role in the virus infection cycle because of the vector's preference. In Southeast Asia, WBPH is a long-distance migratory rice pest. The disease cycle can be described as follows: SRBSDV and its WBPH vector overwinter in warm tropical or sub-tropical areas; viruliferous WBPH adults carry the virus from south to north via long-distance migration in early spring, transmit the virus to rice seedlings in the newly colonized areas, and lay eggs on the infected seedlings; the next generation of WBPHs propagate on infected seedlings, become viruliferous, disperse, and cause new disease outbreaks. Several molecular and serological methods have been developed to detect SRBSDV in plant tissues and individual insects. Control measures based on protection from WBPH, including seedbed coverage, chemical seed treatments, and chemical spraying of seedlings, have proven effective in China.

Influence of Temperature on Symbiotic Bacterium Composition in Successive Generations of Egg Parasitoid, Anagrus nilaparvatae

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Wang Xin

2016-07-01

Full Text Available Anagrus nilaparvatae is the dominant egg parasitoid of rice planthoppers and plays an important role in biological control. Symbiotic bacteria can significantly influence the development, survival, reproduction and population differentiation of their hosts. To study the influence of temperature on symbiotic bacterial composition in the successive generations of A. nilaparvatae, A. nilaparvatae were raised under different constant temperatures of 22 °C, 25 °C, 28 °C, 31 °C and 34 °C. Polymerase chain reaction-denaturing gradient gel electrophoresis was used to investigate the diversity of symbiotic bacteria. Our results revealed that the endophytic bacteria of A. nilaparvatae were Pantoea sp., Pseudomonas sp. and some uncultured bacteria. The bacterial community composition in A. nilaparvatae significantly varied among different temperatures and generations, which might be partially caused by temperature, feeding behavior and the physical changes of hosts. However, the analysis of wsp gene showed that the Wolbachia in A. nilaparvatae belonged to group A, sub-group Mors and sub-group Dro. Sub-group Mors was absolutely dominant, and this Wolbachia composition remained stable in different temperatures and generations, except for the 3rd generation under 34 °C during which sub-group Dro became the dominant Wolbachia. The above results suggest that the continuous high temperature of 34 °C can influence the Wolbachia community composition in A. nilaparvatae.

Evaluasi Sifat Ovisidal dan Nimfasidal Insektisida Buprofezin 100 g/l terhadap Telur dan Nimfa Wereng Coklat, Nilaparvata lugens (Stal. (Hemiptera: Delphacidae

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BAEHAKI SUHERLAN EFFENDI

2016-11-01

Full Text Available Evaluation of ovicidal and nymphcidal properties of buprofezin 100 g/linsecticide to eggs and nymphs of brown planthopper, Nilaparvata lugens(Stal. (Hemiptera: Delphacidae. Research was carried out in screen house ofSukamandi, Indonesian Center for Rice Research (ICRR in the wet season of 2013. Theresearch used randomized block design with 5 doses levels insecticide treatment of buprofezin100 g/l and four replications. The buprofezin treatments were 250, 500, 750, 1000, and 1500ml/ha compared with control without insecticide. The objective of the research to evaluate ofovicidal and nymphcidal of buprofezin to brown planthopper (BPH. The results showed thatthe ovicidal properties of buprofezin 100 g/l with a range doses of treatments to BPH eggsthat application at 5 days after inoculation with eggs remains in the plant tissue were 39,79-94,88%. The raising ovicidal of buprofezin were 74,84-99,5% that applied at 9 days afterinoculation with eggs remains in the plant tissue. In the other hand the ovicidal properties ofbuprofezin decreased dramatically were 20-48% that applied at 5 days after inoculation andthen BPH eggs removed from plant tissue (dissected at 9 days after inoculation. The higherovicidal properties of buprofezin is better in the plant tissue than in the dissected eggs treated,because buprofezin working on eggs in plant tissue as a systemic insecticide. The dissectedBPH eggs of rice treated to show the normal eggs shape and no eggs contracted. Theunhatched eggs of buprofezin treatments were milk white due to insecticide effect, sometranslucent color with a red dot as a fertile eggs or without a red dot as unfertile eggs.Buprofezin was the excellent nymphcidal insecticide with the value of the efficacy to BPHnymphs were very high about 87,44 -100% for a range doses treatments. Buprofezin did notresurgence effect, moreover this insecticides still have ovicidal and nimphcidal properties as abasic to reduce offspring of brown planthopper.

High-resolution genetic mapping at the Bph15 locus for brown planthopper resistance in rice (Oryza sativa L.).

Science.gov (United States)

Yang, Haiyuan; You, Aiqing; Yang, Zhifan; Zhang, Futie; He, Ruifeng; Zhu, Lili; He, Guangcun

2004-12-01

Resistance to the brown planthopper (BPH), Nilaparvata lugens Stal, a devastating sucking insect pest of rice, is an important breeding objective in rice improvement programs. Bph15, one of the 17 major BPH resistance genes so far identified in both cultivated and wild rice, has been identified in an introgression line, B5, and mapped on chromosome 4 flanked by restriction fragment length polymorphism markers C820 and S11182. In order to pave the way for positional cloning of this gene, we have developed a high-resolution genetic map of Bph15 by positioning 21 DNA markers in the target chromosomal region. Mapping was based on a PCR-based screening of 9,472 F(2) individuals derived from a cross between RI93, a selected recombinant inbred line of B5 bearing the resistance gene Bph15, and a susceptible variety, Taichung Native 1, in order to identify recombinant plants within the Bph15 region. Recombinant F(2) individuals with the Bph15 genotype were determined by phenotype evaluation. Analysis of recombination events in the Bph15 region delimited the gene locus to an interval between markers RG1 and RG2 that co-segregated with the M1 marker. A genomic library of B5 was screened using these markers, and bacterial artificial chromosome clones spanning the Bph15 chromosome region were obtained. An assay of the recombinants using the sub-clones of these clones in combination with sequence analysis delimited the Bph15 gene to a genomic segment of approximately 47 kb. This result should serve as the basis for eventual isolation of the Bph15 resistance gene.

Genetic analysis and fine mapping of a rice brown planthopper (Nilaparvata lugens Stål) resistance gene bph19(t).

Science.gov (United States)

Chen, J W; Wang, L; Pang, X F; Pan, Q H

2006-04-01

Genetic analysis and fine mapping of a resistance gene against brown planthopper (BPH) biotype 2 in rice was performed using two F(2) populations derived from two crosses between a resistant indica cultivar (cv.), AS20-1, and two susceptible japonica cvs., Aichi Asahi and Lijiangxintuanheigu. Insect resistance was evaluated using F(1) plants and the two F(2) populations. The results showed that a single recessive gene, tentatively designated as bph19(t), conditioned the resistance in AS20-1. A linkage analysis, mainly employing microsatellite markers, was carried out in the two F(2) populations through bulked segregant analysis and recessive class analysis (RCA), in combination with bioinformatics analysis (BIA). The resistance gene locus bph19(t) was finely mapped to a region of about 1.0 cM on the short arm of chromosome 3, flanked by markers RM6308 and RM3134, where one known marker RM1022, and four new markers, b1, b2, b3 and b4, developed in the present study were co-segregating with the locus. To physically map this locus, the bph19(t)-linked markers were landed on bacterial artificial chromosome or P1 artificial chromosome clones of the reference cv., Nipponbare, released by the International Rice Genome Sequencing Project. Sequence information of these clones was used to construct a physical map of the bph19(t) locus, in silico, by BIA. The bph19(t) locus was physically defined to an interval of about 60 kb. The detailed genetic and physical maps of the bph19(t) locus will facilitate marker-assisted gene pyramiding and cloning.

Development and evaluation of near-isogenic lines for brown planthopper resistance in rice cv. 9311

OpenAIRE

Cong Xiao; Jie Hu; Yi-Ting Ao; Ming-Xing Cheng; Guan-Jun Gao; Qing-Lu Zhang; Guang-Cun He; Yu-Qing He

2016-01-01

Brown planthopper (BPH) is the most destructive pest of rice in Asia. To date 29 BPH resistance genes have been identified, but only a few genes are being used in breeding due to inefficient markers for marker-assisted selection (MAS) and little knowledge of the real effects of the genes. In this study we individually transferred 13 genes or QTLs (Bph14, QBph3, QBph4, Bph17, Bph15, Bph20, Bph24, Bph6, Bph3, Bph9, Bph10, Bph18 and Bph21) into cultivar 9311 by marker assisted backcross breeding...

Genomic insights into the glutathione S-transferase gene family of two rice planthoppers, Nilaparvata lugens (Stal and Sogatella furcifera (Horvath (Hemiptera: Delphacidae.

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Wen-Wu Zhou

Full Text Available BACKGROUND: Glutathione S-transferase (GST genes control crucial traits for the metabolism of various toxins encountered by insects in host plants and the wider environment, including insecticides. The planthoppers Nilaparvata lugens and Sogatella furcifera are serious specialist pests of rice throughout eastern Asia. Their capacity to rapidly adapt to resistant rice varieties and to develop resistance to various insecticides has led to severe outbreaks over the last decade. METHODOLOGY/PRINCIPAL FINDINGS: Using the genome sequence of N. lugens, we identified for the first time the complete GST gene family of a delphacid insect whilst nine GST gene orthologs were identified from the closely related species S. furcifera. Nilaparvata lugens has 11 GST genes belonging to six cytosolic subclasses and a microsomal class, many fewer than seen in other insects with known genomes. Sigma is the largest GST subclass, and the intron-exon pattern deviates significantly from that of other species. Higher GST gene expression in the N. lugens adult migratory form reflects the higher risk of this life stage in encountering the toxins of non-host plants. After exposure to a sub-lethal dose of four insecticides, chlorpyrifos, imidacloprid, buprofezin or beta-cypermethrin, more GST genes were upregulated in S. furcifera than in N. lugens. RNA interference targeting two N. lugens GST genes, NlGSTe1 and NlGSTm2, significantly increased the sensitivity of fourth instar nymphs to chlorpyrifos but not to beta-cypermethrin. CONCLUSIONS/SIGNIFICANCE: This study provides the first elucidation of the nature of the GST gene family in a delphacid species, offering new insights into the evolution of metabolic enzyme genes in insects. Further, the use of RNA interference to identify the GST genes induced by insecticides illustrates likely mechanisms for the tolerance of these insects.

THE ROLES OF DETOXIFYING ENZYMES AND AChE INSENSITIVITY IN METHAMIDOPHOS RESISTANCE DEVELOPMENT AND DECLINE IN NILAPARVATA LUGENS

Institute of Scientific and Technical Information of China (English)

Ze-wenLiu; Zhao-junHan; Ling-chunZhang

2003-01-01

Methamidophos resistance of brown planthopper (Nilaparvata lugens Stal, BPH) was selected in laboratory. After successive selection for 9 generations, the selection was ceased by rearing BPH without contact with any insecticide for 9 generations. In the full course, the successive changes of esterase activity, MFO activity, GSTs activity and AChE insensitivity were analyzed. The results showed that the change of esterase activity was high correlated with that of methamidophos in the full course, which indicated that esterase played very important role both in the resistance development and in the resistance decline. However, the change of AChE insensitivity only significantly correlated with that of resistance in the development stage, and the change of MFO activity or GSTs activity only significantly correlated with that of the resistance in the decline stage, which indicated the changes of AChE insensitivity, MFO activity or GSTs activity only played some roles in different stages of the resistance change.

Fine mapping and characterization of BPH27, a brown planthopper resistance gene from wild rice (Oryza rufipogon Griff.).

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Huang, D; Qiu, Y; Zhang, Y; Huang, F; Meng, J; Wei, S; Li, R; Chen, B

2013-01-01

The brown planthopper (Nilaparvata lugens Stål; BPH) is one of the most serious rice pests worldwide. Growing resistant varieties is the most effective way to manage this insect, and wild rice species are a valuable source of resistance genes for developing resistant cultivars. BPH27 derived from an accession of Guangxi wild rice, Oryza rufipogon Griff. (Accession no. 2183, hereafter named GX2183), was primarily mapped to a 17-cM region on the long arm of the chromosome four. In this study, fine mapping of BPH27 was conducted using two BC(1)F(2) populations derived from introgression lines of GX2183. Insect resistance was evaluated in the BC(1)F(2) populations with 6,010 individual offsprings, and 346 resistance extremes were obtained and employed for fine mapping of BPH27. High-resolution linkage analysis defined the BPH27 locus to an 86.3-kb region in Nipponbare. Regarding the sequence information of rice cultivars, Nipponbare and 93-11, all predicted open reading frames (ORFs) in the fine-mapping region have been annotated as 11 types of proteins, and three ORFs encode disease-related proteins. Moreover, the average BPH numbers showed significant differences in 96-120 h after release in comparisons between the preliminary near-isogenic lines (pre-NILs, lines harboring resistance genes) and BaiR54. BPH growth and development were inhibited and survival rates were lower in the pre-NIL plants compared with the recurrent parent BaiR54. The pre-NIL exhibited 50.7% reductions in population growth rates (PGR) compared to BaiR54. The new development in fine mapping of BPH27 will facilitate the efforts to clone this important resistant gene and to use it in BPH-resistance rice breeding.

Development and characterization of japonica rice lines carrying the brown planthopper-resistance genes BPH12 and BPH6.

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Qiu, Yongfu; Guo, Jianping; Jing, Shengli; Zhu, Lili; He, Guangcun

2012-02-01

The brown planthopper (Nilaparvata lugens Stål; BPH) has become a severe constraint on rice production. Identification and pyramiding BPH-resistance genes is an economical and effective solution to increase the resistance level of rice varieties. All the BPH-resistance genes identified to date have been from indica rice or wild species. The BPH12 gene in the indica rice accession B14 is derived from the wild species Oryza latifolia. Using an F(2) population from a cross between the indica cultivar 93-11 and B14, we mapped the BPH12 gene to a 1.9-cM region on chromosome 4, flanked by the markers RM16459 and RM1305. In this population, BPH12 appeared to be partially dominant and explained 73.8% of the phenotypic variance in BPH resistance. A near-isogenic line (NIL) containing the BPH12 locus in the background of the susceptible japonica variety Nipponbare was developed and crossed with a NIL carrying BPH6 to generate a pyramid line (PYL) with both genes. BPH insects showed significant differences in non-preference in comparisons between the lines harboring resistance genes (NILs and PYL) and Nipponbare. BPH growth and development were inhibited and survival rates were lower on the NIL-BPH12 and NIL-BPH6 plants compared to the recurrent parent Nipponbare. PYL-BPH6 + BPH12 exhibited 46.4, 26.8 and 72.1% reductions in population growth rates (PGR) compared to NIL-BPH12, NIL-BPH6 and Nipponbare, respectively. Furthermore, insect survival rates were the lowest on the PYL-BPH6 + BPH12 plants. These results demonstrated that pyramiding different BPH-resistance genes resulted in stronger antixenotic and antibiotic effects on the BPH insects. This gene pyramiding strategy should be of great benefit for the breeding of BPH-resistant japonica rice varieties.

Purification, molecular cloning and heterologous expression of a glutathione S-transferase involved in insecticide resistance from the rice brown planthopper, Nilaparvata lugens.

OpenAIRE

Vontas, John G; Small, Graham J; Nikou, Dimitra C; Ranson, Hilary; Hemingway, Janet

2002-01-01

A novel glutathione S-transferase (GST)-based pyrethroid resistance mechanism was recently identified in Nilaparvata lugens [Vontas, Small and Hemingway (2001) Biochem. J. 357, 65-72]. To determine the nature of GSTs involved in conferring this resistance, the GSTs from resistant and susceptible strains of N. lugens were partially purified by anion exchange and affinity chromatography. The majority of peroxidase activity, previously correlated with resistance, was confined to the fraction tha...

Identification of transcription factors potential related to brown planthopper resistance in rice via microarray expression profiling

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Wang Yubing

2012-12-01

Full Text Available Abstract Background Brown planthopper (BPH, Nilaparvata lugens Stål, is one of the most destructive insect pests of rice. The molecular responses of plants to sucking insects resemble responses to pathogen infection. However, the molecular mechanism of BPH-resistance in rice remains unclear. Transcription factors (TF are up-stream regulators of various genes that bind to specific DNA sequences, thereby controlling the transcription from DNA to mRNA. They are key regulators for transcriptional expression in biological processes, and are probably involved in the BPH-induced pathways in resistant rice varieties. Results We conducted a microarray experiment to analyze TF genes related to BPH resistance in a Sri Lankan rice cultivar, Rathu Heenati (RHT. We compared the expression profiles of TF genes in RHT with those of the susceptible rice cultivar Taichun Native 1 (TN1. We detected 2038 TF genes showing differential expression signals between the two rice varieties. Of these, 442 TF genes were probably related to BPH-induced resistance in RHT and TN1, and 229 may be related to constitutive resistance only in RHT. These genes showed a fold change (FC of more than 2.0 (P10, there were 37 induced TF genes and 26 constitutive resistance TF genes. Of these, 13 were probably involved in BPH-induced resistance, and 8 in constitutive resistance to BPH in RHT. Conclusions We explored the molecular mechanism of resistance to BPH in rice by comparing expressions of TF genes between RHT and TN1. We speculate that the level of gene repression, especially for early TF genes, plays an important role in the defense response. The fundamental point of the resistance strategy is that plants protect themselves by reducing their metabolic level to inhibit feeding by BPH and prevent damage from water and nutrient loss. We have selected 21 TF genes related to BPH resistance for further analyses to understand the molecular responses to BPH feeding in rice.

Knockdown of NADPH-cytochrome P450 reductase results in reduced resistance to buprofezin in the small brown planthopper, Laodelphax striatellus (fallén).

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Zhang, Yueliang; Wang, Yaming; Wang, Lihua; Yao, Jing; Guo, Huifang; Fang, Jichao

2016-02-01

NADPH-cytochrome P450 reductase (CPR) plays an important role in cytochrome P450 function, and CPR knockdown in several insects leads to increased susceptibility to insecticides. However, a putative CPR gene has not yet been fully characterized in the small brown planthopper Laodelphax striatellus, a notorious agricultural pest in rice that causes serious damage by transmitting rice stripe and rice black-streaked dwarf viruses. The objective of this study was to clone the cDNA and to knock down the expression of the gene that encodes L. striatellus CPR (LsCPR) to further determine whether P450s are involved in the resistance of L. striatellus to buprofezin. First, the full-length cDNA of LsCPR was cloned and found to contain an open reading frame (ORF) encoding a polypeptide of 679 amino acids with a calculated molecular mass and isoelectric point of 76.92kDa and 5.37, respectively. The deduced amino acid sequence shares high identity with the CPRs of other insects (98%, 97%, 75% and 68% for Sogatella furcifera, Nilaparvata lugens, Cimex lectularius and Anopheles gambiae, respectively) and possesses the characteristic features of classical CPRs, such as an N-terminal membrane anchor and conserved domains for flavin mononucleotide (FMN), flavin adenine dinucleotide (FAD) and nicotinamide adenine dinucleotide phosphate (NADPH) binding. Phylogenetic analysis revealed that LsCPR is located in a branch along with the CPRs of other hemipteran insects. LsCPR mRNA was detectable in all examined body parts and developmental stages of L. striatellus, as determined by real-time quantitative PCR (qPCR), and transcripts were most abundant in the adult abdomen and in first-instar nymphs and adults. Ingestion of 200μg/mL of LsCPR double-stranded RNA (dsLsCPR) by the planthopper for 5days significantly reduced the transcription level of LsCPR. Moreover, silencing of LsCPR caused increased susceptibility to buprofezin in a buprofezin-resistant (YN-BPF) strain but not in a

Molecular characterization of the amplified carboxylesterase gene associated with organophosphorus insecticide resistance in the brown planthopper, Nilaparvata lugens.

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Small, G J; Hemingway, J

2000-12-01

Widespread resistance to organophosphorus insecticides (OPs) in Nilaparvata lugens is associated with elevation of carboxylesterase activity. A cDNA encoding a carboxylesterase, Nl-EST1, has been isolated from an OP-resistant Sri Lankan strain of N. lugens. The full-length cDNA codes for a 547-amino acid protein with high homology to other esterases/lipases. Nl-EST1 has an N-terminal hydrophobic signal peptide sequence of 24 amino acids which suggests that the mature protein is secreted from cells expressing it. The nucleotide sequence of the homologue of Nl-EST1 in an OP-susceptible, low esterase Sri Lankan strain of N. lugens is identical to Nl-EST1. Southern analysis of genomic DNA from the Sri Lankan OP-resistant and susceptible strains suggests that Nl-EST1 is amplified in the resistant strain. Therefore, resistance to OPs in the Sri Lankan strain is through amplification of a gene identical to that found in the susceptible strain.

Selectable antibiotic resistance marker gene-free transgenic rice harbouring the garlic leaf lectin gene exhibits resistance to sap-sucking planthoppers.

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Sengupta, Subhadipa; Chakraborti, Dipankar; Mondal, Hossain A; Das, Sampa

2010-03-01

Rice, the major food crop of world is severely affected by homopteran sucking pests. We introduced coding sequence of Allium sativum leaf agglutinin, ASAL, in rice cultivar IR64 to develop sustainable resistance against sap-sucking planthoppers as well as eliminated the selectable antibiotic-resistant marker gene hygromycin phosphotransferase (hpt) exploiting cre/lox site-specific recombination system. An expression vector was constructed containing the coding sequence of ASAL, a potent controlling agent against green leafhoppers (GLH, Nephotettix virescens) and brown planthopper (BPH, Nilaparvata lugens). The selectable marker (hpt) gene cassette was cloned within two lox sites of the same vector. Alongside, another vector was developed with chimeric cre recombinase gene cassette. Reciprocal crosses were performed between three single-copy T(0) plants with ASAL- lox-hpt-lox T-DNA and three single-copy T(0) plants with cre-bar T-DNA. Marker gene excisions were detected in T(1) hybrids through hygromycin sensitivity assay. Molecular analysis of T(1) plants exhibited 27.4% recombination efficiency. T(2) progenies of L03C04(1) hybrid parent showed 25% cre negative ASAL-expressing plants. Northern blot, western blot and ELISA showed significant level of ASAL expression in five marker-free T(2) progeny plants. In planta bioassay of GLH and BPH performed on these T(2) progenies exhibited radical reduction in survivability and fecundity compared with the untransformed control plants.

Diet-dependent fecundity of the spiders Atypena formosana and Pardosa pseudoannulata, predators in irrigated rice

DEFF Research Database (Denmark)

Sigsgaard, L.; Toft, S.; Villareal, S.

2001-01-01

The fecundity of the spiders Atypena formosana and Pardosa pseudoannulata was assessed on diets of brown planthopper Nilaparvata lugens (BPH), green leafhopper Nephotettix virescens (GLH), Collembola (Entomobryidae), Drosophila melanogaster and three prey mixtures; BPH-GLH, BPH-GLH-Collembola and......The fecundity of the spiders Atypena formosana and Pardosa pseudoannulata was assessed on diets of brown planthopper Nilaparvata lugens (BPH), green leafhopper Nephotettix virescens (GLH), Collembola (Entomobryidae), Drosophila melanogaster and three prey mixtures; BPH-GLH, BPH......-GLH-Collembola and a full mixed diet of BPH-GLH-Collembola-D. melanogaster. Egg production and hatching success was high in A. formosana except on the BPH, the GLH and the BPH-GLH diets. In P. pseudoannulata egg production and hatching success was lowest on diets of GLH and BPH-GLH, whereas this spider used BPH better....... Differences between offspring sizes were small. Survival of A. formosana females was lowest on the GLH and BPH-GLH diets. In P. pseudoannulata survival did not differ significantly. Food conversion efficiency was highest on the Collembola and the D. melanogaster diets for both spiders. Overall, diets...

[Double-ambient CO2 concentration affects the growth, development and sucking behavior of non-target brown plant hopper Nilaparvata lugens fed on transgenic Bt rice.

Science.gov (United States)

Lu, Yong Qing; Dai, Yang; Yu, Xiu Ying; Yu, Fu-Lan; Jiang, Shou Lin; Zhou, Zong Yuan; Chen, Fa Jun

2018-02-01

In recent years, the two issues of climate change including elevated CO 2 etc., and resistance of transgenic Bt crops against non-target insect pests have received widespread attention. Elevated CO 2 can affect the herbivorous insects. To date, there is no consensus about the effect of elevated CO 2 on the suck-feeding insect pests (non-target insect pests of transgenic Bt crops). Its effects on the suck-feeding behavior have rarely been reported. In this study, CO 2 levels were set up in artificial climate chamber to examined the effects of ambient (400 μL·L -1 ) and double-ambient (800 μL·L -1 ) CO 2 levels on the suck-feeding behavior, growth, development, and reproduction of the non-target insect pest of transgenic Bt rice, brown planthopper, Nilaparvata lugens. The results showed that CO 2 level significantly affected the egg and nymph duration, longevity and body mass of adults, and feeding behavior of the 4th and 5th instar nymphs, while had no effect on the fecundity of N. lugens. The duration of eggs and nymphs, and the longevity of female adults were significantly shortened by 4.0%, 4.2% and 6.6% respectively, the proportion of the macropterous adults was significantly increased by 11.6%, and the body mass of newly hatched female adults was significantly decreased by 2.2% by elevated CO 2 . In addition, elevated CO 2 significantly enhanced the stylet puncturing efficiency of the 4th and 5th instar nymphs of N. lugens. The duration ofphloem ingestion of the N4b waveform was significantly prolonged by 60.0% and 50.1%, and the frequency significantly was increased by 230.0% and 155.9% for the 4th and 5th instar nymphs of N. lugens by elevated CO 2 , respectively. It was concluded that double-ambient CO 2 could promote the growth and development of N. lugens through enhancing its suck-feeding, shorten the generation life-span and increase the macropertous adults' proportion of N. lugens. Thus, it could result in the occurrence of non-target rice

Metabolic imidacloprid resistance in the brown planthopper, Nilaparvata lugens, relies on multiple P450 enzymes.

Science.gov (United States)

Zhang, Yixi; Yang, Yuanxue; Sun, Huahua; Liu, Zewen

2016-12-01

Target insensitivity contributing to imidacloprid resistance in Nilaparvata lugens has been reported to occur either through point mutations or quantitative change in nicotinic acetylcholine receptors (nAChRs). However, the metabolic resistance, especially the enhanced detoxification by P450 enzymes, is the major mechanism in fields. From one field-originated N. lugens population, an imidacloprid resistant strain G25 and a susceptible counterpart S25 were obtained to analyze putative roles of P450s in imidacloprid resistance. Compared to S25, over-expression of twelve P450 genes was observed in G25, with ratios above 5.0-fold for CYP6AY1, CYP6ER1, CYP6CS1, CYP6CW1, CYP4CE1 and CYP425B1. RNAi against these genes in vivo and recombinant tests on the corresponding proteins in vitro revealed that four P450s, CYP6AY1, CYP6ER1, CYP4CE1 and CYP6CW1, played important roles in imidacloprid resistance. The importance of the four P450s was not equal at different stages of resistance development based on their over-expression levels, among which CYP6ER1 was important at all stages, and that the others might only contribute at certain stages. The results indicated that, to completely reflect roles of P450s in insecticide resistances, their over-expression in resistant individuals, expression changes at the stages of resistance development, and catalytic activities against insecticides should be considered. In this study, multiple P450s, CYP6AY1, CYP6ER1, CYP4CE1 and CYP6CW1, have proven to be important in imidacloprid resistance. Copyright © 2016 Elsevier Ltd. All rights reserved.

Knockdown of TOR causing ovarian diapause in a genetically stable brachypterous strain of Nilaparvata lugens.

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Liu, Fangzhou; Li, Kaiyin; Cai, Wanlun; Zhao, Jing; Zou, Yulan; Hua, Hongxia

2017-08-01

Brown planthopper (BPH), Nilaparvata lugens (Stål) (Hemiptera: Delphacidae), is one of the most damaging pests of rice crops. BPH is a migratory insect with a delayed ovarian development in migrants classified as reproductive diapause. The molecular mechanism of reproductive diapause remains unclear, although we suspect it might be regulated by one or more nutrient signaling pathways. The target of rapamycin (TOR) pathway regulates cell growth in response to nutritional information, which raised a hypothesis that TOR mediates BPH reproductive diapause. We used a pure brachypterous strain (BS) and a predominantly macropterous strain (MS) to investigate the roles of NlTOR in BPH reproductive diapause. We found that NlTOR is expressed from the nymphal to adult stages, with a higher expression level of NlTOR in BS adults at 1, 2, and 4 days posteclosion than in MS at the same time points. Injection of dsNlTOR into BS nymphs resulted in the termination of BPH female ovary development and the retardation of nymph development. We infer that TOR signaling functions in BPH reproductive diapause by regulating the expression of NlFoxA and NlVitellogenin. © 2017 Wiley Periodicals, Inc.

Evaluation of alternative rice planthopper control by the combined action of oil-formulated Metarhizium anisopliae and low-rate buprofezin.

Science.gov (United States)

Jin, Shao-Feng; Feng, Ming-Guang; Ying, Sheng-Hua; Mu, Wen-Jing; Chen, Jue-Qi

2011-01-01

High resistance of brown planthopper (BPH) Nilaparvata lugens Stål to common insecticides is a challenge for control of the pest. An alternative control strategy based on the combined application of fungal and chemical agents has been evaluated. Three gradient spore concentrations of oil-formulated Metarhizium anisopliae (Metschnikoff) Sorokin (Ma456) were sprayed onto third-instar nymphs in five bioassays comprising the low buprofezin rates of 0, 10, 20, 30 and 40 µg mL(-1) respectively. Fungal LC(50) after 1 week at 25 °C and 14:10 h light:dark photoperiod decreased from 386 conidia mm(-2) in the buprofezin-free bioassay to 40 at the highest chemical rate. Buprofezin (LC(50): 1647, 486 and 233 µg mL(-1) on days 2 to 4) had no significant effect on the fungal outgrowths of mycosis-killed cadavers at the low application rates. The fungal infection was found to cause 81% reduction in reproductive potential of BPH adults. In two 40 day field trials, significant planthopper (mainly BPH) control (54-60%) was achieved by biweekly sprays of two fungal candidates (Ma456 and Ma576) at 1.5 × 10(13) conidia ha(-1) and elevated to 80-83% by incorporating 30.8 g buprofezin ha(-1) into the fungal sprays. The combined application of the fungal and chemical agents is a promising alternative strategy for BPH control. Copyright © 2010 Society of Chemical Industry.

High Temperature Effects on Yeast-like Endosymbiotes and Pesticide Resistance of the Small Brown Planthopper, Laodelphax striatellus

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Xiao-jie ZHANG

2008-12-01

Full Text Available The newly-hatched nymphs of the small brown planthopper (SBPH, Laodelphax striatellus, including field and sensitive populations, were subjected to the high-temperature (35°C treatment. The number of yeast-like endosymbiotes in SBPH reduced by 23.47%–34.23%, 57.86%–61.51% and 88.96%–90.71% after the high-temperature treatment for 1 d, 2 d, and 3 d, respectively. However, the size of yeast-like endosymbiotes was not obviously affected. Resistance of SBPH to three insecticides (imidacloprid, chlorpyrifos and fipronil decreased with the increase of treatment time.

Genomic insights into the glutathione S-transferase gene family of two rice planthoppers, Nilaparvata lugens (Stål) and Sogatella furcifera (Horváth) (Hemiptera: Delphacidae).

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Zhou, Wen-Wu; Liang, Qing-Mei; Xu, Yi; Gurr, Geoff M; Bao, Yan-Yuan; Zhou, Xue-Ping; Zhang, Chuan-Xi; Cheng, Jiaan; Zhu, Zeng-Rong

2013-01-01

Glutathione S-transferase (GST) genes control crucial traits for the metabolism of various toxins encountered by insects in host plants and the wider environment, including insecticides. The planthoppers Nilaparvata lugens and Sogatella furcifera are serious specialist pests of rice throughout eastern Asia. Their capacity to rapidly adapt to resistant rice varieties and to develop resistance to various insecticides has led to severe outbreaks over the last decade. Using the genome sequence of N. lugens, we identified for the first time the complete GST gene family of a delphacid insect whilst nine GST gene orthologs were identified from the closely related species S. furcifera. Nilaparvata lugens has 11 GST genes belonging to six cytosolic subclasses and a microsomal class, many fewer than seen in other insects with known genomes. Sigma is the largest GST subclass, and the intron-exon pattern deviates significantly from that of other species. Higher GST gene expression in the N. lugens adult migratory form reflects the higher risk of this life stage in encountering the toxins of non-host plants. After exposure to a sub-lethal dose of four insecticides, chlorpyrifos, imidacloprid, buprofezin or beta-cypermethrin, more GST genes were upregulated in S. furcifera than in N. lugens. RNA interference targeting two N. lugens GST genes, NlGSTe1 and NlGSTm2, significantly increased the sensitivity of fourth instar nymphs to chlorpyrifos but not to beta-cypermethrin. This study provides the first elucidation of the nature of the GST gene family in a delphacid species, offering new insights into the evolution of metabolic enzyme genes in insects. Further, the use of RNA interference to identify the GST genes induced by insecticides illustrates likely mechanisms for the tolerance of these insects.

Gene expression and plant hormone levels in two contrasting rice genotypes responding to brown planthopper infestation.

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Li, Changyan; Luo, Chao; Zhou, Zaihui; Wang, Rui; Ling, Fei; Xiao, Langtao; Lin, Yongjun; Chen, Hao

2017-02-28

The brown planthopper (BPH; Nilaparvata lugens Stål) is a destructive piercing-sucking insect pest of rice. The plant hormones salicylic acid (SA) and jasmonic acid (JA) play important roles in plant-pest interactions. Many isolated rice genes that modulate BPH resistance are involved in the metabolism or signaling pathways of SA, JA and ethylene. 'Rathu Heenati' (RH) is a rice cultivar with a high-level, broad-spectrum resistance to all BPH biotypes. Here, RH was used as the research material, while a BPH-susceptible rice cultivar 'Taichung Native 1' (TN1) was the control. A cDNA microarray analysis illuminated the resistance response at the genome level of RH under BPH infestation. The levels of SA and JA in RH and TN1 seedlings after BPH infestation were also determined. The expression pattern clustering indicated that 1467 differential probe sets may be associated with constitutive resistance and 67 with the BPH infestation-responsive resistance of RH. A Venn diagram analysis revealed 192 RH-specific and BPH-inducible probe sets. Finally, 23 BPH resistance-related gene candidates were selected based on the expression pattern clustering and Venn diagram analysis. In RH, the SA content significantly increased and the JA content significantly decreased after BPH infestation, with the former occurring prior to the latter. In RH, the differential genes in the SA pathway were synthesis-related and were up-regulated after BPH infestation. The differential genes in the JA pathway were also up-regulated. They were jasmonate ZIM-domain transcription factors, which are important negative regulators of the JA pathway. Comparatively, genes involved in the ET pathway were less affected by a BPH infestation in RH. DNA sequence analysis revealed that most BPH infestation-inducible genes may be regulated by the genetic background in a trans-acting manner, instead of by their promoters. We profiled the analysis of the global gene expression in RH and TN1 under BPH infestation

Acetylcholinesterase Inhibitory Activities of Flavonoids from the Leaves of Ginkgo biloba against Brown Planthopper

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Xiao Ding

2013-01-01

Full Text Available Ginkgo biloba is a traditional Chinese medicinal plant which has potent insecticidal activity against brown planthopper. The MeOH extract was tested in the acetylcholinesterase (AChE inhibitory assay with IC50 values of 252.1 μg/mL. Two ginkgolides and thirteen flavonoids were isolated from the leaves of Ginkgo biloba. Their structures were established on the basis of spectroscopic data interpretation. It revealed that the 13 isolated flavonoids were found to inhibit AChE with IC50 values ranging from 57.8 to 133.1 μg/mL in the inhibitory assay. AChE was inhibited dose dependently by all tested flavonoids, and compound 6 displayed the highest inhibitory effect against AChE with IC50 values of 57.8 μg/mL.

Neofunctionalization of Duplicated P450 Genes Drives the Evolution of Insecticide Resistance in the Brown Planthopper.

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Zimmer, Christoph T; Garrood, William T; Singh, Kumar Saurabh; Randall, Emma; Lueke, Bettina; Gutbrod, Oliver; Matthiesen, Svend; Kohler, Maxie; Nauen, Ralf; Davies, T G Emyr; Bass, Chris

2018-01-22

Gene duplication is a major source of genetic variation that has been shown to underpin the evolution of a wide range of adaptive traits [1, 2]. For example, duplication or amplification of genes encoding detoxification enzymes has been shown to play an important role in the evolution of insecticide resistance [3-5]. In this context, gene duplication performs an adaptive function as a result of its effects on gene dosage and not as a source of functional novelty [3, 6-8]. Here, we show that duplication and neofunctionalization of a cytochrome P450, CYP6ER1, led to the evolution of insecticide resistance in the brown planthopper. Considerable genetic variation was observed in the coding sequence of CYP6ER1 in populations of brown planthopper collected from across Asia, but just two sequence variants are highly overexpressed in resistant strains and metabolize imidacloprid. Both variants are characterized by profound amino-acid alterations in substrate recognition sites, and the introduction of these mutations into a susceptible P450 sequence is sufficient to confer resistance. CYP6ER1 is duplicated in resistant strains with individuals carrying paralogs with and without the gain-of-function mutations. Despite numerical parity in the genome, the susceptible and mutant copies exhibit marked asymmetry in their expression with the resistant paralogs overexpressed. In the primary resistance-conferring CYP6ER1 variant, this results from an extended region of novel sequence upstream of the gene that provides enhanced expression. Our findings illustrate the versatility of gene duplication in providing opportunities for functional and regulatory innovation during the evolution of an adaptive trait. Copyright © 2017 The Authors. Published by Elsevier Ltd.. All rights reserved.

Transcriptome Analysis of the Small Brown Planthopper, Laodelphax striatellus Carrying Rice stripe virus

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Joo Hyun Lee

2013-09-01

Full Text Available Rice stripe virus (RSV, the type member of the genus Tenuivirus, transmits by the feeding behavior of small brown planthopper (SBPH, Laodelphax striatellus. To investigate the interactions between the virus and vector insect, total RNA was extracted from RSV-viruliferous SBPH (RVLS and non-viruliferous SBPH (NVLS adults to construct expressed sequence tag databases for comparative transcriptome analysis. Over 30 million bases were sequenced by 454 pyrosequencing to construct 1,538 and 953 of isotigs from the mRNA of RVLS and NVLS, respectively. The gene ontology (GO analysis demonstrated that both libraries have similar GO structures, however, the gene expression pattern analysis revealed that 17.8% and 16.8% of isotigs were up- and down-regulated significantly in the RVLS, respectively. These RSV-dependently regulated genes possibly have important roles in the physiology of SBPH, transmission of RSV, and RSV and SBPH interaction.

Functional analysis of CYP6ER1, a P450 gene associated with imidacloprid resistance in Nilaparvata lugens.

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Pang, Rui; Chen, Meng; Liang, Zhikun; Yue, Xiangzhao; Ge, Hu; Zhang, Wenqing

2016-10-10

The cytochrome P450 CYP6ER1 has been reported to play an important role in imidacloprid resistance of the brown planthopper (BPH), Nilaparvata lugens, and is overexpressed in most resistant populations. In the present study, we confirmed that CYP6ER1 expression can be induced by certain levels of imidacloprid. Developmental expression analysis revealed that CYP6ER1 was expressed highly in the adult stage, and tissue distribution analysis showed that CYP6ER1 was expressed mainly in the fat body and midgut. RNA interference (RNAi) of CYP6ER1 and transgenic expression of CYP6ER1 in Drosophila melanogaster both suggested that the expression of CYP6ER1 is sufficient to confer imidacloprid resistance. Furthermore, we analyzed the interaction of imidacloprid and CYP6ER1 monooxygenase by using dynamic simulations and molecular docking. We found that Nitrogen atoms in the heterocycle of the imidacloprid molecule may bind to iron atoms in the center of the homology model of CYP6ER1 via 4,5-dihedro-1H-imidazole. This finding contributes to a better understanding of how CYP6ER1 takes part in the insecticide metabolism.

Identification of transcription factors potential related to brown planthopper resistance in rice via microarray expression profiling.

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Wang, Yubing; Guo, Huimin; Li, Haichao; Zhang, Hao; Miao, Xuexia

2012-12-10

Brown planthopper (BPH), Nilaparvata lugens Stål, is one of the most destructive insect pests of rice. The molecular responses of plants to sucking insects resemble responses to pathogen infection. However, the molecular mechanism of BPH-resistance in rice remains unclear. Transcription factors (TF) are up-stream regulators of various genes that bind to specific DNA sequences, thereby controlling the transcription from DNA to mRNA. They are key regulators for transcriptional expression in biological processes, and are probably involved in the BPH-induced pathways in resistant rice varieties. We conducted a microarray experiment to analyze TF genes related to BPH resistance in a Sri Lankan rice cultivar, Rathu Heenati (RHT). We compared the expression profiles of TF genes in RHT with those of the susceptible rice cultivar Taichun Native 1 (TN1). We detected 2038 TF genes showing differential expression signals between the two rice varieties. Of these, 442 TF genes were probably related to BPH-induced resistance in RHT and TN1, and 229 may be related to constitutive resistance only in RHT. These genes showed a fold change (FC) of more than 2.0 (Pgenes related to BPH-induced resistance, most of them were readily induced in TN1 than in RHT by BPH feeding, for instance, 154 TF genes were up-regulated in TN1, but only 31 TF genes were up-regulated in RHT at 24 hours after BPH infestation; 2-4 times more TF genes were induced in TN1 than in RHT by BPH. At an FC threshold of >10, there were 37 induced TF genes and 26 constitutive resistance TF genes. Of these, 13 were probably involved in BPH-induced resistance, and 8 in constitutive resistance to BPH in RHT. We explored the molecular mechanism of resistance to BPH in rice by comparing expressions of TF genes between RHT and TN1. We speculate that the level of gene repression, especially for early TF genes, plays an important role in the defense response. The fundamental point of the resistance strategy is that plants

Attraction behaviour of Anagrus nilaparvatae to remote lemongrass (Cymbopogon distans) oil and its volatile compounds.

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Mao, Guo-Feng; Mo, Xiao-Chang; Fouad, Hatem; Abbas, Ghulam; Mo, Jian-Chu

2018-03-01

Utilisation of Anagrus nilaparvatae is a promising and effective method for planthoppers manipulation. Twenty-seven components of remote lemongrass (Cymbopogon distans) oil were identified by GC/MS and nine volatiles were selected for behavioural experiments. In this study, we noted that the remote lemongrass oil was attractive to female A. nilaparvatae at concentrations of 0.1 and 1 mg/L. α-Pinene, β-pinene, eucalyptol, carveol and D-carvone attracted female wasps in the dose-dependent bioassays. Blend 1 (a mixture of eucalyptol, D-carvone, carveol, α-pinene, and β-pinene with ratios of remote lemongrass oil volatiles of 625:80:11:5:3) attracted female wasps at 10 mg/L, while blend 2 (a mixture of the same five volatiles at the same loading ratio) attracted them at 0.1 and 1 mg/L. These results suggested that plant essential oils could be attractants for natural enemies to control pests. The ratios of volatiles in the mixtures affect the attractiveness of the synthetic mixtures.

Molecular Breeding of Rice Restorer Lines and Hybrids for Brown Planthopper (BPH) Resistance Using the Bph14 and Bph15 Genes.

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Wang, Hongbo; Ye, Shengtuo; Mou, Tongmin

2016-12-01

The development of hybrid rice is a practical approach for increasing rice production. However, the brown planthopper (BPH), Nilaparvata lugens Stål, causes severe yield loss of rice (Oryza sativa L.) and can threaten food security. Therefore, breeding hybrid rice resistant to BPH is the most effective and economical strategy to maintain high and stable production. Fortunately, numerous BPH resistance genes have been identified, and abundant linkage markers are available for molecular marker-assisted selection (MAS) in breeding programs. Hence, we pyramided two BPH resistance genes, Bph14 and Bph15, into a susceptive CMS restorer line Huahui938 and its derived hybrids using MAS to improve the BPH resistance of hybrid rice. Three near-isogenic lines (NILs) with pyramided Bph14 and Bph15 were obtained by molecular marker-assisted backcross (MAB) and phenotypic selection. The genomic components of these NILs were detected using the whole-genome SNP (Single nucleotide polymorphism) array, RICE6K, suggesting that the recurrent parent genome (RPG) recovery of the NILs was 87.88, 87.70 and 86.62 %, respectively. BPH bioassays showed that the improved NILs and their derived hybrids carrying homozygous Bph14 and Bph15 were resistant to BPH. However, the hybrids with heterozygous Bph14 and Bph15 remained susceptible to BPH. The developed NILs showed no significant differences in major agronomic traits and rice qualities compared with the recurrent parent. Moreover, the improved hybrids derived from the NILs exhibited better agronomic performance and rice quality compared with the controls under natural field conditions. This study demonstrates that it is essential to stack Bph14 and Bph15 into both the maternal and paternal parents for developing BPH-resistant hybrid rice varieties. The SNP array with abundant DNA markers is an efficient tool for analyzing the RPG recovery of progenies and can be used to monitor the donor segments in NILs, thus being extremely important

Recent progress on the genetics and molecular breeding of brown planthopper resistance in rice.

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Hu, Jie; Xiao, Cong; He, Yuqing

2016-12-01

Brown planthopper (BPH) is the most devastating pest of rice. Host-plant resistance is the most desirable and economic strategy in the management of BPH. To date, 29 major BPH resistance genes have been identified from indica cultivars and wild rice species, and more than ten genes have been fine mapped to chromosome regions of less than 200 kb. Four genes (Bph14, Bph26, Bph17 and bph29) have been cloned. The increasing number of fine-mapped and cloned genes provide a solid foundation for development of functional markers for use in breeding. Several BPH resistant introgression lines (ILs), near-isogenic lines (NILs) and pyramided lines (PLs) carrying single or multiple resistance genes were developed by marker assisted backcross breeding (MABC). Here we review recent progress on the genetics and molecular breeding of BPH resistance in rice. Prospect for developing cultivars with durable, broad-spectrum BPH resistance are discussed.

High-resolution mapping of the brown planthopper resistance gene Bph6 in rice and characterizing its resistance in the 9311 and Nipponbare near isogenic backgrounds.

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Qiu, Yongfu; Guo, Jianping; Jing, Shengli; Zhu, Lili; He, Guangcun

2010-11-01

Brown planthopper (Nilaparvata lugens Stål, BPH) is one of the most destructive insect pests of rice. Exploring resistance genes from diverse germplasms and incorporating them into cultivated varieties are critical for controlling this insect. The rice variety Swarnalata was reported to carry a resistance gene (designated Bph6), which has not yet been assigned to a chromosome location and the resistance mechanism is still unknown. In this study, we identified and mapped this gene using the F(2) and backcrossing populations and characterized its resistance in indica 9311 and japonica Nipponbare using near isogenic lines (NILs). In analysis of 9311/Swarnalata F(2) population, the Bph6 gene was located on the long arm of chromosome 4 between the SSR markers RM6997 and RM5742. The gene was further mapped precisely to a 25-kb region delimited between the STS markers Y19 and Y9; and the distance between these markers is 25-kb in Nipponbare genome. The Bph6 explained 77.5% of the phenotypic variance of BPH resistance in F(2) population and 84.9% in BC(2)F(2) population. Allele from Swarnalata significantly increased resistance to the BPH, resulted in a reduced damage score. In characterization of Bph6-mediated resistance, the BPH insects showed significant preference between NIL-9311 and 9311 in 3 h and between NIL-NIP and Nipponbare in 120 h after release. BPH growth and development were inhibited, and the insect's survival rates were lower on Bph6-NIL plants, compared with the parents 9311 and Nipponbare. The results indicate that the Bph6 exerted prolonged antixenotic and antibiotic effects in Bph6-NIL plants, and NIL-9311 plants showed a quicker and stronger effect toward BPH than NIL-NIP plants.

Expression and RNA Interference of Ribosomal Protein L5 Gene in Nilaparvata lugens (Hemiptera: Delphacidae).

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Zhu, Jiajun; Hao, Peiying; Lu, Chaofeng; Ma, Yan; Feng, Yalin; Yu, Xiaoping

2017-05-01

The ribosomal proteins play important roles in the growth and development of organisms. This study aimed to explore the function of NlRPL5 (GenBank KX379234), a ribosomal protein L5 gene, in the brown planthopper Nilaparvata lugens. The open reading frame of NlRPL5 was cloned from N. lugens based on a previous transcriptome analysis. The results revealed that the open reading frame of NlRPL5 is of 900 bp, encoding 299 amino acid residues. The reverse transcription quantitative PCR results suggested that the expression of NlRPL5 gene was stronger in gravid females, but was relatively low in nymphs, males, and newly emerged females. The expression level of NlRPL5 in the ovary was about twofolds of that in the head, thorax, or fat body. RNAi of dsNlRPL5 resulted in a significant reduction of mRNA levels, ∼50% decrease in comparison with the dsGFP control at day 6. Treatment of dsNlRPL5 significantly restricted the ovarian development, and decreased the number of eggs laid on the rice (Oryza sativa) plants. This study provided a new clue for further study on the function and regulation mechanism of NlRPL5 in N. lugens. © The Author 2017. Published by Oxford University Press on behalf of the Entomological Society of America.

Point mutations in acetylcholinesterase 1 associated with chlorpyrifos resistance in the brown planthopper, Nilaparvata lugens Stål.

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Zhang, Y; Yang, B; Li, J; Liu, M; Liu, Z

2017-08-01

Insecticide resistance frequently results from target-site insensitivity, such as point mutations in acetylcholinesterases (AChEs) for resistance to organophosphates and carbamates. From a field-originated population of Nilaparvata lugens, a major rice pest, a resistant population (R9) was obtained by nine-generation continuous selection with chlorpyrifos. From the same field population, a relatively susceptible population (S9) was also constructed through rearing without any insecticides. Compared to the susceptible strain, Sus [medium lethal dose (LC 50 ) = 0.012 mg/l], R9 had a resistance ratio (RR) of 253.08-fold, whereas the RR of S9 was only 2.25-fold. Piperonyl butoxide and triphenyl phosphate synergized chlorpyrifos in R9 less than three-fold, indicating other important mechanisms for high resistance. The target-site insensitivity was supported by the key property differences of crude AChEs between R9 and S9. Compared to S9, three mutations (G119S, F331C and I332L) were detected in NlAChE1 from individuals of the R9 and field populations, but no mutation was detected in NlAChE2. G119S and F331C could decreased insecticide sensitivities in recombinant NlAChE1, whereas I332L took effect through increasing the influence of F331C on target insensitivity. F331C might be deleterious because of its influence on the catalytic efficiency of NlAChE1, whereas I332L would decrease these adverse effects and maintain the normal functions of AChEs. © 2017 The Royal Entomological Society.

Physical mapping of Bph3, a brown planthopper resistance locus in rice

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Jirapong Jairin

2007-09-01

Full Text Available Resistance to brown planthopper (BPH, a destructive phloem feeding insect pest, is an important objective in rice breeding programs in Thailand. The broad-spectrum resistance gene Bph3 is one of the major BPH resistance genes identified so far in cultivated rice and has been widely used in rice improvement programs. This resistance gene has been identified and mapped on the short arm of chromosome 6. In this study, physical mapping of Bph3 was performed using a BC3F3 population derived from a cross between Rathu Heenati and KDML105. Recombinant BC3F3 individuals with the Bph3 genotype were determined by phenotypic evaluation using modified mass tiller screening at the vegetative stage of rice plants. The recombination events surrounding the Bph3 locus were used to identify the co-segregate markers. According to the genome sequence of Nipponbare, the Bph3 locus was finally localized approximately in a 190 kb interval flanked by markers RM19291 and RM8072, which contain twenty-two putative genes. Additional phenotypic experiment revealed that the resistance in Rathu Heenati was decreased by increasing nitrogen content in rice plants through remobilization of nitrogen. This phenomenon should be helpful for identifying the Bph3 gene.

Induction of P450 genes in Nilaparvata lugens and Sogatella furcifera by two neonicotinoid insecticides.

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Yang, Yuan-Xue; Yu, Na; Zhang, Jian-Hua; Zhang, Yi-Xi; Liu, Ze-Wen

2018-06-01

Nilaparvata lugens and Sogatella furcifera are two primary planthoppers on rice throughout Asian countries and areas. Neonicotinoid insecticides, such as imidacloprid (IMI), have been extensively used to control rice planthoppers and IMI resistance consequently occurred with an important mechanism from the over-expression of P450 genes. The induction of P450 genes by IMI may increase the ability to metabolize this insecticide in planthoppers and increase the resistance risk. In this study, the induction of P450 genes was compared in S. furcifera treated with IMI and nitromethyleneimidazole (NMI), in two planthopper species by IMI lethal dose that kills 85% of the population (LD 85 ), and in N. lugens among three IMI doses (LD 15 , LD 50 and LD 85 ). When IMI and NMI at the LD 85 dose were applied to S. furcifera, the expression changes in most P450 genes were similar, including the up-regulation of nine genes and down-regulation of three genes. In terms of the expression changes in 12 homologous P450 genes between N. lugens and S. furcifera treated with IMI at the LD 85 dose, 10 genes had very similar patterns, such as up-regulation in seven genes, down-regulation in one gene and no significant changes in two genes. When three different IMI doses were applied to N. lugens, the changes in P450 gene expression were much different, such as up-regulation in four genes at all doses and dose-dependent regulation of the other nine genes. For example, CYP6AY1 could be induced by all IMI doses, while CYP6ER1 was only up-regulated by the LD 50 dose, although both genes were reported important in IMI resistance. In conclusion, P450 genes in two planthopper species showed similar regulation patterns in responding to IMI, and the two neonicotinoid insecticides had similar effects on P450 gene expression, although the regulation was often dose-dependent. © 2017 Institute of Zoology, Chinese Academy of Sciences.

Effects of nitrogen on egg-laying inhibition and ovicidal response in planthopper-resistant rice varieties.

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Horgan, Finbarr G; Srinivasan, Thanga Suja; Naik, Bhaskar S; Ramal, Angelee Fame; Bernal, Carmencita C; Almazan, Maria Liberty P

2016-11-01

A series of experiments was set up to examine the effects of nitrogen on rice ( Oryza sativa L.) resistance against Nilaparvata lugens (Stål) and Sogatella furcifera (Horváth). Egg laying by N. lugens was reduced on the indica variety IR60. Nymph biomass ( N. lugens and S. furcifera ) was also lower on IR60: this was associated with low honeydew production and a high proportion of xylem-derived honeydew in N. lugens but not in S. furcifera . Nitrogen increased egg-laying by S. furcifera and increased N. lugens nymph biomass on all varieties tested. Oviposition and egg mortality in both planthopper species were examined on plants at 15, 30 and 45 days after sowing (DAS). Sogatella furcifera laid more eggs on plants at 15 DAS, but laid few eggs during darkness; N. lugens continued to lay eggs on older rice plants (30 DAS) and during darkness. Egg mortality was high on cv. Asiminori, highest at 45 DAS, and higher for S. furcifera than for N. lugens . Mortality of S. furcifera eggs was associated with lesions around the egg clusters. These were more common around clusters laid during the day and suggested induction by Asiminori of an ovicidal response. Egg mortality declined under higher soil nitrogen levels. Results are discussed in the light of improving rice resistance against planthoppers and reducing rates of planthopper adaptation to resistance genes.

The roles of CYP6AY1 and CYP6ER1 in imidacloprid resistance in the brown planthopper: Expression levels and detoxification efficiency.

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Bao, Haibo; Gao, Hongli; Zhang, Yixi; Fan, Dongzhe; Fang, Jichao; Liu, Zewen

2016-05-01

Two P450 monooxygenase genes, CYP6AY1 and CYP6ER1, were reported to contribute importantly to imidacloprid resistance in the brown planthopper, Nilaparvata lugens. Although recombinant CYP6AY1 could metabolize imidacloprid efficiently, the expression levels of CYP6ER1 gene were higher in most resistant populations. In the present study, three field populations were collected from different countries, and the bioassay, RNAi and imidacloprid metabolism were performed to evaluate the importance of two P450s in imidacloprid resistance. All three populations, DOT (Dongtai) from China, CNA (Chainat) from Thailand and HCM (Ho Chi Minh) from Vietnam, showed high resistance to imidacloprid (57.0-, 102.9- and 89.0-fold). CYP6AY1 and CYP6ER1 were both over expressed in three populations, with highest ratio of 13.2-fold for CYP6ER1 in HCM population. Synergism test and RNAi analysis confirmed the roles of both P450 genes in imidacloprid resistance. However, CYP6AY1 was indicated more important in CNA population, and CYP6AY1 and CYP6ER1 were equal in HCM population, although the expression level of CYP6ER1 (13.2-fold) was much higher than that of CYP6AY1 (4.11-fold) in HCM population. Although the recombinant proteins of both P450 genes could metabolize imidacloprid efficiently, the catalytic activity of CYP6AY1 (Kcat=3.627 pmol/min/pmol P450) was significantly higher than that of CYP6ER1 (Kcat=2.785 pmol/min/pmol P450). It was supposed that both P450 proteins were important for imidacloprid resistance, in which CYP6AY1 metabolized imidacloprid more efficiently and CYP6ER1 gene could be regulated by imidacloprid to a higher level. Copyright © 2015 Elsevier B.V. All rights reserved.

Effects of Population Density and Host Availability on The Migration Process of Brown Planthopper Fed Using Susceptible and Resistant Rice Varieties

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Imam Habibi

2016-12-01

Full Text Available Brown planthopper, Nilaparvata lugens Stal. (Hemiptera: Delphacidae, is an important pest of rice. This pest can cause hopperburn and field failure. This research aimed to determine the effects of population density and host availability on migration of N. lugens. The criteria used to justify the effects of host availability and population density on migration of N. lugens were based the hardness and tannin tests of the rice stems, fecundity of N. lugens, and the life cycle of N. lugens. The research was conducted under the temperature of 29.42°C with relative humidity of 61% and Light 12: Dark 12 times, using ten pairs of N. lugens brachypterous (F0 constant and then was added with five male adults on fifth days after the first infestation (F0 changed. The varieties used were IR64, as a resistant variety, and Ketan Lusi, as a susceptible variety. The results showed that the adding of the macropterous males did not affect the number of macropterous, because of that has been preplanned by the F0. Therefore, the percentage of existing macropterous was 51−52%.   INTISARI   Wereng Batang Cokelat (WBC merupakan salah satu hama tanaman padi yang sangat penting. Kerusakan parah dapat menyebabkan hopperburn dan puso (gagal panen. Tujuan penelitian ini adalah mengetahui pengaruh kepadatan populasi dan tanaman inang sebagai tempat migrasi WBC. Parameter yang dikaji untuk mengetahui pengaruh kepadatan populasi WBC dan tanaman inang tempat migrasi WBC berdasarkan tingkat kekerasan dan kandungan tanin batang tanaman padi, fekunditas WBC, dan siklus hidup WBC. Penelitian ini dilakukan pada temperatur 29.42˚C dengan kelembapan relatif 61% dan durasi siang hari 12 jam: durasi malam hari 12 jam. Metode yang dilakukan adalah dengan menggunakan 10 pasang imago WBC brakhiptera (F0 konstan, kemudian dilakukan penambahan 5 ekor imago jantan pada hari kelima setelah infestasi awal (F0 diubah. Varietas padi yang digunakan yaitu padi varietas IR64 sebagai varietas

Fine mapping of the rice Bph1 gene, which confers resistance to the brown planthopper (Nilaparvata lugens stal), and development of STS markers for marker-assisted selection.

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Cha, Young-Soon; Ji, Hyeonso; Yun, Doh-Won; Ahn, Byoung-Ohg; Lee, Myung Chul; Suh, Seok-Cheol; Lee, Chun Seok; Ahn, Eok Keun; Jeon, Yong-Hee; Jin, Il-Doo; Sohn, Jae-Keun; Koh, Hee-Jong; Eun, Moo-Young

2008-08-31

The brown planthopper (BPH) is a major insect pest in rice, and damages these plants by sucking phloem-sap and transmitting viral diseases. Many BPH resistance genes have been identified in indica varieties and wild rice accessions, but none has yet been cloned. In the present study we report fine mapping of the region containing the Bph1 locus, which enabled us to perform marker-aided selection (MAS). We used 273 F8 recombinant inbred lines (RILs) derived from a cross between Cheongcheongbyeo, an indica type variety harboring Bph1 from Mudgo, and Hwayeongbyeo, a BPH susceptible japonica variety. By random amplification of polymorphic DNA (RAPD) analysis using 656 random 10-mer primers, three RAPD markers (OPH09, OPA10 and OPA15) linked to Bph1 were identified and converted to SCAR (sequence characterized amplified region) markers. These markers were found to be contained in two BAC clones derived from chromosome 12: OPH09 on OSJNBa0011B18, and both OPA10 and OPA15 on OSJNBa0040E10. By sequence analysis of ten additional BAC clones evenly distributed between OSJNBa0011B18 and OSJNBa0040E10, we developed 15 STS markers. Of these, pBPH4 and pBPH14 flanked Bph1 at distances of 0.2 cM and 0.8 cM, respectively. The STS markers pBPH9, pBPH19, pBPH20, and pBPH21 co-segregated with Bph1. These markers were shown to be very useful for marker-assisted selection (MAS) in breeding populations of 32 F6 RILs from a cross between Andabyeo and IR71190, and 32 F5 RILs from a cross between Andabyeo and Suwon452.

Imidacloprid-susceptible Nilaparvata lugens individuals exceeded resistant individuals in a mixture population with density pressure.

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Yu, Na; Tian, Jiahua; Zhang, Yixi; Li, Zhong; Liu, Zewen

2018-01-01

Fitness costs associated with insecticide resistance in pest insects have mainly been studied under optimal laboratory conditions. However, resistant insects face more stressors than just insecticides in the field, and how the resistant population reacts to these stressors is of practical importance for the control of pest insects such as the brown planthopper Nilaparvata lugens. The aim of the present study was to explore the impact of population density on the competitiveness of resistant and susceptible individuals. Two isogenic N. lugens populations, a highly imidacloprid-resistant population (HZ-R) with a resistance ratio (RR) of 227.10 and a relatively susceptible population (HZ-S) with an RR of 2.99, were created from a field-resistant population (HZ; RR 62.51). The high resistance levels of HZ-R and HZ were mainly attributable to the overexpression of multiple cytochrome P450 (CYP) genes such as CYP6ER1, CYP6AY1, CYP6CW1 and CYP4CE1 compared with HZ-S, this being supported by piperonyl butoxide synergism. HZ-R was observed to be more resistant to thiacloprid and etofenprox compared with HZ and HZ-S. Most interestingly, in high population density treatments, HZ-S individuals were much more competitive than HZ-R individuals. Imidacloprid-resistant individuals of N. lugens are less competitive than their susceptible counterparts under density pressure. © 2017 Society of Chemical Industry. © 2017 Society of Chemical Industry.

Characterization and functional analysis of a carboxylesterase gene associated with chlorpyrifos resistance in Nilaparvata lugens (Stål).

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Lu, Kai; Wang, Ying; Chen, Xia; Zhang, Zhichao; Li, Yue; Li, Wenru; Zhou, Qiang

2017-12-01

The widespread and extensive application of insecticides have promoted the development of resistance in the brown planthopper Nilaparvata lugens (Stål), one of the most important rice pests in Asia. To better understand the underlying molecular mechanisms of metabolic resistance to insecticides, a chlorpyrifos-resistant (CR) strain of N. lugens was selected and its possible resistance mechanism was investigated. Synergistic tests using carboxylesterases (CarEs) inhibitor triphenyl phosphate (TPP) decreased the resistance of N. lugens to chlorpyrifos, and CarE activities could be induced by low concentrations of chlorpyrifos. Subsequently, a gene putatively encoding CarE, namely NlCarE, predominant in the midgut and ovary was isolated and characterized. The expression levels of NlCarE were detected and compared between the CR and a susceptible (SS) strain of N. lugens. Consistent with the increased CarE activity, this gene was overexpressed in the CR strain compared to the SS strain. The transcript levels of NlCarE were up-regulated by chlorpyrifos exposure, showing dose- and time-dependent expression patterns. Furthermore, RNA interference (RNAi)-mediated knockdown of NlCarE followed by insecticide application significantly increased the susceptibility of N. lugens to chlorpyrifos. These results demonstrate that NlCarE plays an important role in chlorpyrifos detoxification and its overexpression may be involved in chlorpyrifos resistance in N. lugens. Copyright © 2017 Elsevier Inc. All rights reserved.

Dinamika populasi wereng punggung putih, sogatella furcifera Stål (Hemiptera: Delphacidae di jawa tengah

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I Nyoman Widiarta

2017-02-01

Full Text Available A field study was conducted at paddy fields in Petarukan and Pekalongan regencies of Central Java province during wet season crop 1989/90 and 1990/91 to elucidate population dynamic of whitebacked planthopper, Sogatella furcifera Stål. Seven and three observation fields were set up in 1989/90 and the 1990/91, respectively. Cisadane rice cultivar was transplanted following the usual farmer’s parctices except that no pesticide was applied. The population of the whitebacked planthopper and the brown planthopper, (Nilaparvata lugens Stål were sampled by using an insect suction catcher, a farmcop. Identification of generation was based on thermal constant required by the whitebacked planthopper to complete one generation and mean population density was calculated by graphical method. Two distinct seasonal population growth patterns were identified. The population with short population growth pattern completed four generations in one crop season in which their population density increased consecutively in two generations since immigrant generation, and thereafter decreased. The population with long population growth completed five generations in one crop season in which their population density increased consecutively in three generations, and thereafter decreased. The density of brachiptera adults determined 90% of the total population density. The proportion of brachiptera adults were not correlated with large nymphal density in both vegetative and generative stages of rice. The proportion of brachiptera adults showed significant negative linear regression with population density of the brown planthopper. Therefore, interspesific competition determined the proportion of wingform and population dynamics of the whitebacked planthopper.

Distinct expression profiles and different functions of odorant binding proteins in Nilaparvata lugens Stål.

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Peng He

Full Text Available BACKGROUND: Odorant binding proteins (OBPs play important roles in insect olfaction. The brown planthopper (BPH, Nilaparvata lugens Stål (Delphacidae, Auchenorrhyncha, Hemiptera is one of the most important rice pests. Its monophagy (only feeding on rice, wing form (long and short wing variation, and annual long distance migration (seeking for rice plants of high nutrition imply that the olfaction would play a central role in BPH behavior. However, the olfaction related proteins have not been characterized in this insect. METHODOLOGY/PRINCIPAL FINDINGS: Full length cDNA of three OBPs were obtained and distinct expression profiles were revealed regarding to tissue, developmental stage, wing form and gender for the first time for the species. The results provide important clues in functional differentiation of these genes. Binding assays with 41 compounds demonstrated that NlugOBP3 had markedly higher binding ability and wider binding spectrum than the other two OBPs. Terpenes and Ketones displayed higher binding while Alkanes showed no binding to the three OBPs. Focused on NlugOBP3, RNA interference experiments showed that NlugOBP3 not only involved in nymph olfaction on rice seedlings, but also had non-olfactory functions, as it was closely related to nymph survival. CONCLUSIONS: NlugOBP3 plays important roles in both olfaction and survival of BPH. It may serve as a potential target for developing behavioral disruptant and/or lethal agent in N. lugens.

The Commonly Used Bactericide Bismerthiazol Promotes Rice Defenses against Herbivores

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Pengyong Zhou

2018-04-01

Full Text Available Chemical elicitors that enhance plant resistance to pathogens have been extensively studied, however, chemical elicitors that induce plant defenses against insect pests have received little attention. Here, we found that the exogenous application of a commonly used bactericide, bismerthiazol, on rice induced the biosynthesis of constitutive and/or elicited jasmonic acid (JA, jasmonoyl-isoleucine conjugate (JA-Ile, ethylene and H2O2 but not salicylic acid. These activated signaling pathways altered the volatile profile of rice plants. White-backed planthopper (WBPH, Sogatella furcifera nymphs and gravid females showed a preference for feeding and/or oviposition on control plants: survival rates were better and more eggs were laid than on bismerthiazol-treated plants. Moreover, bismerthiazol treatment also increased both the parasitism rate of WBPH eggs laid on plants in the field by Anagrus nilaparvatae, and also the resistance of rice to the brown planthopper (BPH Nilaparvata lugens and the striped stem borer (SSB Chilo suppressalis. These findings suggest that the bactericide bismerthiazol can induce the direct and/or indirect resistance of rice to multiple insect pests, and so can be used as a broad-spectrum chemical elicitor.

BAC and RNA sequencing reveal the brown planthopper resistance gene BPH15 in a recombination cold spot that mediates a unique defense mechanism.

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Lv, Wentang; Du, Ba; Shangguan, Xinxin; Zhao, Yan; Pan, Yufang; Zhu, Lili; He, Yuqing; He, Guangcun

2014-08-11

Brown planthopper (BPH, Nilaparvata lugens Stål), is the most destructive phloem-feeding insect pest of rice (Oryza sativa). The BPH-resistance gene BPH15 has been proved to be effective in controlling the pest and widely applied in rice breeding programs. Nevertheless, molecular mechanism of the resistance remain unclear. In this study, we narrowed down the position of BPH15 on chromosome 4 and investigated the transcriptome of BPH15 rice after BPH attacked. We analyzed 13,000 BC2F2 plants of cross between susceptible rice TN1 and the recombinant inbred line RI93 that carrying the BPH15 gene from original resistant donor B5. BPH15 was mapped to a 0.0269 cM region on chromosome 4, which is 210-kb in the reference genome of Nipponbare. Sequencing bacterial artificial chromosome (BAC) clones that span the BPH15 region revealed that the physical size of BPH15 region in resistant rice B5 is 580-kb, much bigger than the corresponding region in the reference genome of Nipponbare. There were 87 predicted genes in the BPH15 region in resistant rice. The expression profiles of predicted genes were analyzed. Four jacalin-related lectin proteins genes and one LRR protein gene were found constitutively expressed in resistant parent and considered the candidate genes of BPH15. The transcriptomes of resistant BPH15 introgression line and the susceptible recipient line were analyzed using high-throughput RNA sequencing. In total, 2,914 differentially expressed genes (DEGs) were identified. BPH-responsive transcript profiles were distinct between resistant and susceptible plants and between the early stage (6 h after infestation, HAI) and late stage (48 HAI). The key defense mechanism was related to jasmonate signaling, ethylene signaling, receptor kinase, MAPK cascades, Ca(2+) signaling, PR genes, transcription factors, and protein posttranslational modifications. Our work combined BAC and RNA sequencing to identify candidate genes of BPH15 and revealed the resistance mechanism

Categories and inheritance of resistance to Nilaparvata lugens (Hemiptera: Delphacidae) in mutants of indica rice 'IR64'.

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Sangha, Jatinder Singh; Chen, Yolanda H; Palchamy, Kadirvel; Jahn, Gary C; Maheswaran, M; Adalla, Candida B; Leung, Hei

2008-04-01

Varietal mutants can be useful for developing durable resistance, understanding categories of resistance, and identifying candidate genes involved in defense responses. We used mutants of rice 'IR64' to isolate new sources of resistance to the planthopper Nilaparvata lugens (Stål) (Hemiptera: Delphacidae). We compared two mutants that showed a gain and loss of resistance to N. lugens, to determine the categories of resistance to this pest. Under choice tests, female planthoppers avoided settling and laid fewer eggs on the resistant mutant 'D518' than on the susceptible mutant D1131, susceptible check 'TN1', and wild-type IR64, indicating that antixenosis was the resistance category. Similarly, under no-choice conditions, planthoppers laid 29% fewer eggs in D518 than in IR64, but they oviposited more in 'D1131' and TN1. Honeydew excretion was greater on D1131 seedlings but slightly lower on D518 than on IR64. Nymphal survival and adult female weight did not differ among rice cultivars. D518 showed higher tolerance of N. lugens infestations than IR64. Genetic analysis of the F1, F2, and F3 populations derived from D518 x IR64 revealed that resistance in D518 is dominant and controlled by a single gene. Despite the variation in resistance to N. lugens, both mutants and IR64 performed similarly in the field. The mutant D518 is a new source of durable resistance to N. lugens, mainly due to enhanced antixenosis to female hoppers for settling and oviposition.

Reduction in mRNA and protein expression of a nicotinic acetylcholine receptor α8 subunit is associated with resistance to imidacloprid in the brown planthopper, Nilaparvata lugens.

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Zhang, Yixi; Wang, Xin; Yang, Baojun; Hu, Yuanyuan; Huang, Lixin; Bass, Chris; Liu, Zewen

2015-11-01

Target-site resistance is commonly caused by qualitative changes in insecticide target-receptors and few studies have implicated quantitative changes in insecticide targets in resistance. Here we show that resistance to imidacloprid in a selected strain of Nilaparvata lugens is associated with a reduction in expression levels of the nicotinic acetylcholine receptor (nAChR) subunit Nlα8. Synergism bioassays of the selected strain suggested resistance was conferred, in part, by a target-site mechanism. Sequencing of N. lugens nAChR subunit genes identified no mutations associated with resistance, however, a decrease in mRNA and protein levels of Nlα8 was observed during selection. RNA interference knockdown of Nlα8 decreased the sensitivity of N. lugens to imidacloprid, demonstrating that a decrease in Nlα8 expression is sufficient to confer resistance in vivo. Radioligand binding assays revealed that the affinity of the high-affinity imidacloprid-binding site of native nAChRs was reduced by selection, and reducing the amount of Nlα8 cRNA injected into Xenopus oocytes significantly decreased imidacloprid potency on recombinant receptors. Taken together, these results provide strong evidence that a decrease in Nlα8 levels confers resistance to imidacloprid in N. lugens, and thus provides a rare example of target-site resistance associated with a quantitative rather than qualitative change. In insects, target-site mutations often cause high resistance to insecticides, such as neonicotinoids acting on nicotinic acetylcholine receptors (nAChRs). Here we found that a quantitative change in target-protein level, decrease in mRNA and protein levels of Nlα8, contributed importantly to imidacloprid resistance in Nilaparvata lugens. This finding provides a new target-site mechanism of insecticide resistance. © 2015 International Society for Neurochemistry.

Mechanisms of callose deposition in rice regulated by exogenous abscisic acid and its involvement in rice resistance to Nilaparvata lugens Stål (Hemiptera: Delphacidae).

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Liu, Jinglan; Du, Haitao; Ding, Xu; Zhou, Yaodong; Xie, Pengfei; Wu, Jincai

2017-12-01

Callose is a plant cell wall polysaccharide controlled by β-1,3-glucanase and synthase. Abscisic acid (ABA) is an important plant hormone. Exogenous ABA promotes rice resistance to pests. Whether exogenous ABA could reduce the decline in rice yield after brown planthopper (Nilaparvata lugens Stål; BPH) feeding is an important question, however, the mechanisms behind rice resistance induced by ABA remain obscure. Electronic penetration graph (EPG) recording indicated a significant increase in rice resistance to BPH, and the number of BPH eggs decreased significantly upon application of exogenous ABA. As the concentration of ABA increased, the reduction in rice yield decreased significantly after BPH feeding. Further studies showed that β-1,3-glucanase activity was significantly lower, but synthase activity was higher after ABA treatment than in controls. Our results demonstrated that exogenous ABA suppressed β-1,3-glucanase and induced synthase activity, and promoted callose deposition. This is an important defense mechanism that prevents BPH from ingesting phloem sap. These studies provide support for an insect-resistance mechanism after ABA treatment and provide a reference for the integrated management of other piercing-sucking pests. © 2017 Society of Chemical Industry. © 2017 Society of Chemical Industry.

Identification and Function Analysis of enolase Gene NlEno1 from Nilaparvata lugens (Stål) (Hemiptera:Delphacidae)

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Wang, Wei-Xia; Li, Kai-Long; Chen, Yang; Lai, Feng-Xiang; Fu, Qiang

2015-01-01

The enolase [EC 4.2.1.11] is an essential enzyme in the glycolytic pathway catalyzing the conversion of 2-phosphoglycerate (2-PGE) to phosphoenolpyruvate (PEP). In this study, a full-length cDNA encoding α-enolase was cloned from rice brown planthopper (Nilaparvata lugens) and is provisionally designated as NlEno1. The cDNA sequence of NlEno1 was 1,851 bp with an open reading frame (ORF) of 1,305 bp and encoding 434 amino acids. The deduced protein shares high identity of 80–87% with ENO1-like protein from Hemiptera, Diptera, and Lepidoptera speices. The NlEno1 showed the highest mRNA expression level in hemolymph, followed by fat body, salivary gland, ovaries and egg, and showed trace mRNA levels in testis. The mRNA of NlEno1 showed up-regulated level in virulent N. lugens population Mudgo, IR56 and IR42 when compared with TN1 population. Injection of double-stranded RNA (dsRNA) of NlEno1 into the adults significantly down-regulated the NlEno1 mRNA level along with decreased eggs and offspring. Moreover, injection of NlEno1-dsRNA decreased mRNA level of Vitellogenin (Vg) gene. These results showed that the NlEno1, as a key glycolytic enzyme, may play roles in regulation of fecundity and adaptation of N. lugens to resistant rice varieties. PMID:26056319

Purification, molecular cloning and heterologous expression of a glutathione S-transferase involved in insecticide resistance from the rice brown planthopper, Nilaparvata lugens.

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Vontas, John G; Small, Graham J; Nikou, Dimitra C; Ranson, Hilary; Hemingway, Janet

2002-03-01

A novel glutathione S-transferase (GST)-based pyrethroid resistance mechanism was recently identified in Nilaparvata lugens [Vontas, Small and Hemingway (2001) Biochem. J. 357, 65-72]. To determine the nature of GSTs involved in conferring this resistance, the GSTs from resistant and susceptible strains of N. lugens were partially purified by anion exchange and affinity chromatography. The majority of peroxidase activity, previously correlated with resistance, was confined to the fraction that bound to the affinity column, which was considerably elevated in the resistant insects. A cDNA clone encoding a GST (nlgst1-1) - the first reported GST sequence from Hemiptera with up to 54% deduced amino-acid identity with other insect class I GSTs - was isolated from a pyrethroid-resistant strain. Northern analysis showed that nlgst1-1 was overexpressed in resistant insects. nlgst1-1 was expressed in Escherichia coli, purified and characterized. The ability of the recombinant protein to bind to the S-hexylglutathione affinity matrix, its substrate specificities and its immunological properties confirmed that this GST was one from the elevated subset of N. lugens GSTs. Peroxidase activity of the recombinant nlgst1-1 indicated that it had a role in resistance, through detoxification of lipid peroxidation products induced by pyrethroids. Southern analysis of genomic DNA from the resistant and susceptible strains indicated that GST-based insecticide resistance may be associated with gene amplification in N. lugens.

Community structure, dispersal ability and functional profiling of microbiome existing in fat body and ovary of the brown planthopper, Nilaparvata lugens.

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Zhang, Jian-Hua; Yu, Na; Xu, Xi-Xia; Liu, Ze-Wen

2018-02-09

The endosymbionts play vital roles in growth, development and reproduction in insects. Yeast-like endosymbionts (YLSs) have been well studied in Nilaparvata lugens (N. lugens), but little is known about the tissue-specific bacterial microbiomes, especially on the microbial intersection among internal tissues. Here, the correlation of microbial composition, structure, dispersal ability and functional profiling were illuminated in two tissues, the fat body and ovary in N. lugens. A total of 11 phyla and 105 genera were captured from all samples; Firmicutes and Proteobacteria were the most predominant and accounted for more than 99% in all samples. However, the relative abundance of Firmicutes and Proteobacteria was significantly different in ovary and fat body through Fisher's Least Significant Difference test. Microbial diversity but not the richness index in the two tissues exhibited significant difference. Furthermore, the microbial community structure of the ovary and fat body were primarily determined by tissue quality. Firmicutes showed strong dispersal ability between ovary and fat body based on the quantitative null model assessing, indicating the frequent interaction of these microbiomes in the two tissues. In addition, the Kyoto Encyclopedia of Genes and Genomes pathways of microbial participation were delineated. The ten most abundant pathways counted for over 46% of the annotation and were shared between the two tissues, mainly containing Energy Metabolism and Amino Acid Metabolism/Biosynthesis. The results will provide insights into the correlation of microbial community structure between ovary and fat body of N. lugens. © 2018 Institute of Zoology, Chinese Academy of Sciences.

Metabolic resistance in Nilaparvata lugens to etofenprox, a non-ester pyrethroid insecticide.

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Sun, Huahua; Yang, Baojun; Zhang, Yixi; Liu, Zewen

2017-03-01

Etofenprox, a non-ester pyrethroid insecticide, will be registered to control rice pests such as the brown planthopper (BPH, Nilaparvata lugens Stål) in mainland China. Insecticide resistance is always a problem to the effective control of N. lugens by chemical insecticides. An etofenprox resistance selection of N. lugens was performed in order to understand the related mechanisms. Through successive selection by etofenprox for 16 generations in the laboratory, an etofenprox-resistant strain (G16) with the resistance ratio (RR) of 422.3-fold was obtained. The resistance was partly synergised (2.68-fold) with the metabolic inhibitor PBO, suggesting a role for P450 monooxygenases. In this study, 11 P450 genes were significantly up-regulated in G16, among which eight genes was above 2.0-fold higher than that in US16, a population with the same origin of G16 but without contacting any insecticide in the laboratory. The expression level of four genes (CYP6AY1, CYP6FU1 and CYP408A1 from Clade 3, and CYP425A1 from Clade 4) were above 4.0-fold when compared to US16. RNA interference (RNAi) was performed to evaluate the importance of the selected P450s in etofenprox resistance. When CYP6FU1, CYP425A1 or CYP6AY1 was interfered, the susceptibility was significantly recovered in both G16 and US16, while the knockdown of CYP408A1 or CYP353D1 did not cause significant changes in etofenprox susceptibility. We supposed that CYP6FU1 was the most important P450 member for etofenprox resistance because of the highest expression level and the most noticeable effects on resistance ratios following RNAi. Copyright © 2016 Elsevier Inc. All rights reserved.

Functional Study of Cytochrome P450 Enzymes from the Brown Planthopper (Nilaparvata lugens Stål) to Analyze Its Adaptation to BPH-Resistant Rice.

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Peng, Lei; Zhao, Yan; Wang, Huiying; Song, Chengpan; Shangguan, Xinxin; Ma, Yinhua; Zhu, Lili; He, Guangcun

2017-01-01

Plant-insect interactions constitute a complex of system, whereby plants synthesize toxic compounds as the main defense strategy to combat herbivore assault, and insects deploy detoxification systems to cope with toxic plant compounds. Cytochrom P450s are among the main detoxification enzymes employed by insects to combat the chemical defenses of host plants. In this study, we used Nilaparvata lugens (BPH) to constitute an ideal system for studying plant-insect interactions. By feeding BPHs with artificial diets containing ethanol extracts, we show that biotype Y BPHs have a greater ability to metabolize exogenous substrates than biotype 1 BPHs. NlCPR knockdown inhibited the ability of BPHs to feed on YHY15. qRT-PCR was used to screen genes in the P450 family, and upregulation of CYP4C61, CYP6AX1 , and CYP6AY1 induced by YHY15 was investigated. When the three P450 genes were knocked down, only CYP4C61 dsRNA treatment was inhibited the ability of BPHs to feed on YHY15. These results indicate that BPH P450 enzymes are a key factor in the physiological functions of BPH when feeding on BPH-resistant rice.

Allelic diversity in an NLR gene BPH9 enables rice to combat planthopper variation.

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Zhao, Yan; Huang, Jin; Wang, Zhizheng; Jing, Shengli; Wang, Yang; Ouyang, Yidan; Cai, Baodong; Xin, Xiu-Fang; Liu, Xin; Zhang, Chunxiao; Pan, Yufang; Ma, Rui; Li, Qiaofeng; Jiang, Weihua; Zeng, Ya; Shangguan, Xinxin; Wang, Huiying; Du, Bo; Zhu, Lili; Xu, Xun; Feng, Yu-Qi; He, Sheng Yang; Chen, Rongzhi; Zhang, Qifa; He, Guangcun

2016-10-24

Brown planthopper (BPH), Nilaparvata lugens Stål, is one of the most devastating insect pests of rice (Oryza sativa L.). Currently, 30 BPH-resistance genes have been genetically defined, most of which are clustered on specific chromosome regions. Here, we describe molecular cloning and characterization of a BPH-resistance gene, BPH9, mapped on the long arm of rice chromosome 12 (12L). BPH9 encodes a rare type of nucleotide-binding and leucine-rich repeat (NLR)-containing protein that localizes to the endomembrane system and causes a cell death phenotype. BPH9 activates salicylic acid- and jasmonic acid-signaling pathways in rice plants and confers both antixenosis and antibiosis to BPH. We further demonstrated that the eight BPH-resistance genes that are clustered on chromosome 12L, including the widely used BPH1, are allelic with each other. To honor the priority in the literature, we thus designated this locus as BPH1/9 These eight genes can be classified into four allelotypes, BPH1/9-1, -2, -7, and -9 These allelotypes confer varying levels of resistance to different biotypes of BPH. The coding region of BPH1/9 shows a high level of diversity in rice germplasm. Homologous fragments of the nucleotide-binding (NB) and leucine-rich repeat (LRR) domains exist, which might have served as a repository for generating allele diversity. Our findings reveal a rice plant strategy for modifying the genetic information to gain the upper hand in the struggle against insect herbivores. Further exploration of natural allelic variation and artificial shuffling within this gene may allow breeding to be tailored to control emerging biotypes of BPH.

Characterization and comparative profiling of the small RNA transcriptomes in the Hemipteran insect Nilaparvata lugens.

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Zha, Wenjun; Zhou, Lei; Li, Sanhe; Liu, Kai; Yang, Guocai; Chen, Zhijun; Liu, Kai; Xu, Huashan; Li, Peide; Hussain, Saddam; You, Aiqing

2016-12-20

MicroRNAs (miRNAs) are a group of small RNAs involved in various biological processes through negative regulation of mRNAs at the post-transcriptional level. The brown planthopper (BPH), Nilaparvata lugens (Stål), is one of the most serious and destructive insect pests of rice. In the present study, two small RNA libraries of virulent N. lugens populations (Biotype I survives on susceptive rice variety TN1 and Biotype Y survives on moderately resistant rice variety YHY15) were constructed and sequenced using the high-throughput sequencing technology in order to identify the relationship between miRNAs of N.lugens and adaptation of BPH pests to rice resistance. In total 15,758,632 and 11,442,592 reads, corresponding to 3,144,026 and 2,550,049 unique sequences, were obtained in the two libraries (BPH-TN1 and BPH-YHY15 libraries), respectively. A total of 41 potential novel miRNAs were predicted in the two libraries, and 26 miRNAs showed significantly differential expression between two libraries. All miRNAs were significantly up-regulated in the BPH-TN1 library. Target genes likely regulated by these differentially expressed miRNAs were predicted using computational prediction. The functional annotation of target genes performed by Gene Ontology enrichment (GO) and Kyoto Encyclopedia of Genes and Genomes pathway analysis (KEGG) indicated that a majority of differential miRNAs were involved in "Metabolism" pathway. These results provided an understanding of the role of miRNAs in BPH to adaptability of BPH on rice resistance, and will be useful in developing new control strategies for host defense against BPH. Copyright © 2016 Elsevier B.V. All rights reserved.

Functional Study of Cytochrome P450 Enzymes from the Brown Planthopper (Nilaparvata lugens Stål to Analyze Its Adaptation to BPH-Resistant Rice

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Lei Peng

2017-11-01

Full Text Available Plant-insect interactions constitute a complex of system, whereby plants synthesize toxic compounds as the main defense strategy to combat herbivore assault, and insects deploy detoxification systems to cope with toxic plant compounds. Cytochrom P450s are among the main detoxification enzymes employed by insects to combat the chemical defenses of host plants. In this study, we used Nilaparvata lugens (BPH to constitute an ideal system for studying plant-insect interactions. By feeding BPHs with artificial diets containing ethanol extracts, we show that biotype Y BPHs have a greater ability to metabolize exogenous substrates than biotype 1 BPHs. NlCPR knockdown inhibited the ability of BPHs to feed on YHY15. qRT-PCR was used to screen genes in the P450 family, and upregulation of CYP4C61, CYP6AX1, and CYP6AY1 induced by YHY15 was investigated. When the three P450 genes were knocked down, only CYP4C61 dsRNA treatment was inhibited the ability of BPHs to feed on YHY15. These results indicate that BPH P450 enzymes are a key factor in the physiological functions of BPH when feeding on BPH-resistant rice.

Jinggangmycin-suppressed reproduction in the small brown planthopper (SBPH), Laodelphax striatellus (Fallen), is mediated by glucose dehydrogenase (GDH).

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Ding, Jun; Wu, You; You, Lin-Lin; Xu, Bin; Ge, Lin-Quan; Yang, Guo-Qing; Wu, Jin-Cai

2017-06-01

The small brown planthopper (SBPH), Laodelphax striatellus (Fallen), is a serious pest insect of rice, wheat, and maize in China. SBPH not only sucks plant sap but also transmits plant disease viruses, causing serious damage. These viruses include rice striped virus disease (RSV disease), black streaked dwarf, and maize rough disease virus. SBPH outbreaks are related to the overuse of pesticides in China. Some pesticides, such as triazophos, stimulate the reproduction of SBPH, but an antibiotic fungicide jinggangmycin (JGM) suppresses its reproduction. However, mechanisms of decreased reproduction of SBPH induced by JGM remain unclear. The present findings show that JGM suppressed reproduction of SBPH (↓approximately 35.7%) and resulted in the down-regulated expression of glucose dehydrogenase (GDH). GDH-silenced control females (control+dsGDH) show that the number of eggs laid was reduced by 48.6% compared to control females. Biochemical tests show that the total lipid and fatty acid contents in JGM-treated and control+dsGDH females decreased significantly. Thus, we propose that the suppression of reproduction in SBPH induced by JGM is mediated by GDH via metabolic pathways. Copyright © 2017 Elsevier Inc. All rights reserved.

Detecting Rice stripe virus (RSV) in the small brown planthopper (Laodelphax striatellus) with high specificity by RT-PCR.

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Lijun, Cai; Xizhi, Ma; Lin, Kang; Kejing, Deng; Shouyuan, Zhao; Changben, Li

2003-09-01

Rice stripe disease, caused by Rice stripe virus (RSV), may lead to severe or even crippling losses in many rice-cultured countries and regions. As the most important vector of RSV, the small brown planthopper (SBPH) (Laodelphax striatellus) is largely responsible for the epidemic phase of the disease. Therefore, a rapid identification of RSV in the SBPH is of a great need for disease forecasting. A reverse transcription polymerase chain reaction (RT-PCR) assay is described to amplify a RSV gene in individual L. striatellus. By using primers matched to the viral RNA dependent RNA polymerase gene in RNA1, a 445 bp product was detected in viruliferous SBPHs. Meanwhile, the PCR products produced by the SBPH actin primers constructed across the boundary of an intron and an exon were used as RNA specific positive control for each stage of the experiment to ensure the validity of the negative results. Duplex RT-PCR conditions were established for the simultaneous detection of RSV and actin. This approach can be used for the early detection of RSV in L. striatellus and the subsequent rice stripe disease forecasting.

Characterization of heat shock protein 70 transcript from Nilaparvata lugens (Stål): Its response to temperature and insecticide stresses.

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Lu, Kai; Chen, Xia; Liu, Wenting; Zhang, Zhichao; Wang, Ying; You, Keke; Li, Yue; Zhang, Rongbin; Zhou, Qiang

2017-10-01

The brown planthopper, Nilaparvata lugens, possesses a strong adaptability to extreme temperature and insecticide stresses. Heat shock proteins (Hsps) are highly conserved molecular chaperones and play a pivotal role in response to various environmental stresses in insects. However, little is known about the response of Hsps to stresses in N. lugens. In the present study, an inducible Hsp70 (NlHsp70) was isolated from this insect and transcriptional expression patterns of NlHsp70 under temperature and insecticide stresses were analyzed. The full-length of NlHsp70 was 2805bp with an open reading frame (ORF) of 1896bp, showing high homology to its counterparts in other species. Expression of NlHsp70 was not altered by heat shock for 1h, nor following recovery from thermal stress. Conversely, decreased expression of NlHsp70 was observed in response to cold shock. In addition, the expression of NlHsp70 increased after imidacloprid exposure. RNA interference experiment combined with insecticide injury assay also demonstrated that NlHsp70 was essential for resistance against insecticide exposure. These observations indicated that NlHsp70 was an important gene involved in the resistance or tolerance to environmental stresses in N. lugens. Interestingly, weak changes in mRNA expression levels of two thermal-inducible Hsp genes, NlHsp90 and NlHsc70 were observed in imidacloprid-exposed N. lugens adults, suggesting that different Hsps may respond differential to the extreme temperature and insecticide stresses. Copyright © 2017 Elsevier Inc. All rights reserved.

Identification of a heat shock protein 90 gene involved in resistance to temperature stress in two wing-morphs of Nilaparvata lugens (Stål).

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Lu, Kai; Chen, Xia; Liu, Wenting; Zhou, Qiang

2016-07-01

The brown planthopper, Nilaparvata lugens, is one of the most destructive pests damaging rice in Asia and exhibits wing dimorphism, with brachypters possessing severely reduced wings and macropters bearing fully developed wings. Previous studies have shown that macropters are more heat resistant than brachypters. To understand the molecular mechanism underlying the differential thermotolerance abilities of these two morphs, a full-length Hsp gene, NlHsp90 was cloned from N. lugen. Our results showed that the relative expression levels of NlHsp90 in N. lugens females increased with the rise of temperature. Interestingly, NlHsp90 in macropters females could be induced at lower temperature (32°C) than that in brachypters (34°C), and the NlHsp90 mRNA levels in macropters were significantly higher than those in brachypters from 34 to 40°C. In addition, the maximum expression levels of NlHsp90 were achieved much earlier in macropters, and NlHsp90 mRNA levels in macropters were significantly higher than those in brachypters from 1 to 6h of recovery after temperature stress. Furthermore, knockdown of NlHsp90 by dsRNA injection reduced survival in both morphs with a greater reduction in the macropters relative to that of the brachyters. These results indicated that NlHsp90 plays an important role for thermotolerance in N. lugens, and there is difference on induction between two morphs. Copyright © 2016 Elsevier Inc. All rights reserved.

Identification and Characterization of MicroRNAs in Small Brown Planthopper (Laodephax striatellus) by Next-Generation Sequencing

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Lou, Yonggen; Cheng, Jia'an; Zhang, Hengmu; Xu, Jian-Hong

2014-01-01

MicroRNAs (miRNAs) are endogenous non-coding small RNAs that regulate gene expression at the post-transcriptional level and are thought to play critical roles in many metabolic activities in eukaryotes. The small brown planthopper (Laodephax striatellus Fallén), one of the most destructive agricultural pests, causes great damage to crops including rice, wheat, and maize. However, information about the genome of L. striatellus is limited. In this study, a small RNA library was constructed from a mixed L. striatellus population and sequenced by Solexa sequencing technology. A total of 501 mature miRNAs were identified, including 227 conserved and 274 novel miRNAs belonging to 125 and 250 families, respectively. Sixty-nine conserved miRNAs that are included in 38 families are predicted to have an RNA secondary structure typically found in miRNAs. Many miRNAs were validated by stem-loop RT-PCR. Comparison with the miRNAs in 84 animal species from miRBase showed that the conserved miRNA families we identified are highly conserved in the Arthropoda phylum. Furthermore, miRanda predicted 2701 target genes for 378 miRNAs, which could be categorized into 52 functional groups annotated by gene ontology. The function of miRNA target genes was found to be very similar between conserved and novel miRNAs. This study of miRNAs in L. striatellus will provide new information and enhance the understanding of the role of miRNAs in the regulation of L. striatellus metabolism and development. PMID:25057821

Identification and characterization of microRNAs in small brown planthopper (Laodephax striatellus by next-generation sequencing.

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Guoyan Zhou

Full Text Available MicroRNAs (miRNAs are endogenous non-coding small RNAs that regulate gene expression at the post-transcriptional level and are thought to play critical roles in many metabolic activities in eukaryotes. The small brown planthopper (Laodephax striatellus Fallén, one of the most destructive agricultural pests, causes great damage to crops including rice, wheat, and maize. However, information about the genome of L. striatellus is limited. In this study, a small RNA library was constructed from a mixed L. striatellus population and sequenced by Solexa sequencing technology. A total of 501 mature miRNAs were identified, including 227 conserved and 274 novel miRNAs belonging to 125 and 250 families, respectively. Sixty-nine conserved miRNAs that are included in 38 families are predicted to have an RNA secondary structure typically found in miRNAs. Many miRNAs were validated by stem-loop RT-PCR. Comparison with the miRNAs in 84 animal species from miRBase showed that the conserved miRNA families we identified are highly conserved in the Arthropoda phylum. Furthermore, miRanda predicted 2701 target genes for 378 miRNAs, which could be categorized into 52 functional groups annotated by gene ontology. The function of miRNA target genes was found to be very similar between conserved and novel miRNAs. This study of miRNAs in L. striatellus will provide new information and enhance the understanding of the role of miRNAs in the regulation of L. striatellus metabolism and development.

Phloem-specific expression of the lectin gene from Allium sativum confers resistance to the sap-sucker Nilaparvata lugens.

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Chandrasekhar, Kottakota; Vijayalakshmi, Muvva; Vani, Kalasamudramu; Kaul, Tanushri; Reddy, Malireddy K

2014-05-01

Rice production is severely hampered by insect pests. Garlic lectin gene (ASAL) holds great promise in conferring protection against chewing (lepidopteran) and sap-sucking (homopteran) insect pests. We have developed transgenic rice lines resistant to sap-sucking brown hopper (Nilaparvata lugens) by ectopic expression of ASAL in their phloem tissues. Molecular analyses of T0 lines confirmed stable integration of transgene. T1 lines (NP 1-2, 4-3, 11-6 & 17-7) showed active transcription and translation of ASAL transgene. ELISA revealed ASAL expression was as high as 0.95% of total soluble protein. Insect bioassays on T2 homozygous lines (NP 18 & 32) revealed significant reduction (~74-83%) in survival rate, development and fecundity of brown hoppers in comparison to wild type. Transgenics exhibited enhanced resistance (1-2 score) against brown hoppers, minimal plant damage and no growth penalty or phenotypic abnormalities.

Expression induction of P450 genes by imidacloprid in Nilaparvata lugens: A genome-scale analysis.

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Zhang, Jianhua; Zhang, Yixi; Wang, Yunchao; Yang, Yuanxue; Cang, Xinzhu; Liu, Zewen

2016-09-01

The overexpression of P450 monooxygenase genes is a main mechanism for the resistance to imidacloprid, a representative neonicotinoid insecticide, in Nilaparvata lugens (brown planthopper, BPH). However, only two P450 genes (CYP6AY1 and CYP6ER1), among fifty-four P450 genes identified from BPH genome database, have been reported to play important roles in imidacloprid resistance until now. In this study, after the confirmation of important roles of P450s in imidacloprid resistance by the synergism analysis, the expression induction by imidacloprid was determined for all P450 genes. In the susceptible (Sus) strain, eight P450 genes in Clade4, eight in Clade3 and two in Clade2 were up-regulated by imidacloprid, among which three genes (CYP6CS1, CYP6CW1 and CYP6ER1, all in Clade3) were increased to above 4.0-fold and eight genes to above 2.0-fold. In contrast, no P450 genes were induced in Mito clade. Eight genes induced to above 2.0-fold were selected to determine their expression and induced levels in Huzhou population, in which piperonyl butoxide showed the biggest effects on imidacloprid toxicity among eight field populations. The expression levels of seven P450 genes were higher in Huzhou population than that in Sus strain, with the biggest differences for CYP6CS1 (9.8-fold), CYP6ER1 (7.7-fold) and CYP6AY1 (5.1-fold). The induction levels for all tested genes were bigger in Sus strain than that in Huzhou population except CYP425B1. Screening the induction of P450 genes by imidacloprid in the genome-scale will provide an overall view on the possible metabolic factors in the resistance to neonicotinoid insecticides. The further work, such as the functional study of recombinant proteins, will be performed to validate the roles of these P450s in imidacloprid resistance. Copyright © 2015 Elsevier B.V. All rights reserved.

Characterization of soluble and membrane-bound alkaline phosphatase in Nilaparvata lugens and their potential relation to development and insecticide resistance.

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Wang, Zengxia; Liu, Shuhua; Yang, Baojun; Liu, Zewen

2011-09-01

Two forms (soluble and membrane-bound) of alkaline phosphatases (ALPs) were found in the brown planthopper, Nilaparvata lugens. In order to further study ALPs in N. lugens, two putative ALP genes (Nl-ALP1 and Nl-ALP2) were identified in this pest. Both Nl-ALP1 and Nl-ALP2 show approximately the same degree of sequence identity (40-50%) to other insect soluble and membrane-bound forms of ALP. Correlation of ALP activity and mRNA levels at different developmental stages, or following application of 20-hydroxyecdysone (20E) and insecticide fenvalerate, suggests that Nl-ALP1 and Nl-ALP2 might encode a soluble (sALP) and a membrane-bound ALP (mALP), respectively. Nl-ALP1-specific antibody Nl1-I detected only a specific band in soluble protein preparations and Nl-ALP2 specific antibody Nl2-I only detected a specific band in insoluble protein preparations, which provided conclusive linkages between Nl-ALP1 and a sALP and between Nl-ALP2 and a m ALP. Then, Nl-ALP1 was denoted as Nl-sALP for a sALP and Nl-ALP2 was denoted as Nl-mALP for a mALP. Only sALP activity and Nl-sALP mRNA level were induced by 20E and fenvalerate, which was confirmed by the density of specific band detected by Nl1-I in Sus strain with or without fenvalerate treatment. Additionally, the sALP activity, as well as Nl-sALP mRNA level, was significantly higher in a fenvalerate resistant population, compared with Sus strain. These results indicate that the sALP is more responsive to chemical stimulus, such as hormone and insecticide, and might play dual roles in development and insecticide tolerance. © 2011 Wiley Periodicals, Inc.

Analisis senyawa volatil dari ekstrak tanaman yang berpotensi sebagai atraktan parasitoid telur wereng batang coklat, Anagrus nilaparvatae (Pang et Wang (Hymenoptera: Mymaridae

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Surjani Wonorahardjo

2015-09-01

Full Text Available Plants produce volatiles as communication cues intra- or inter- species. Infested plants by herbivores will produce volatiles as indirect defense mechanism that attracts natural enemies of herbivores. Analysis of volatiles compounds produced by rice plant as result of infested brown plant hopper (BPH, Nilaparvata lugens Stâl, was done to identify compounds in the volatiles that potentially can be used as attractant for egg parasitoids of BPH, Anagrus nilaparvatae (Pang et Wang (Hymenoptera: Mymaridae. This research was an early stage to develop formulation of parasitoid attractant. The research activities include volatiles extraction of infested rice stem by BPH eggs using acetone, n-hexane as the extraction solvents; analyses of volatile compounds with GC-MS; and bioassay of parasitoid orientation behavior to the volatiles using olfactometer methods. Extraction methods applied were maceration and continuous extraction followed by concentration. Bioassay on the parasitoid orientation behavior was done by using Y-tube olfactometer and every lot of bioassay using 30 parasitoid females with 3 replicates. The results showed that the volatile compounds of extract of infested rice stem by BPH eggs comprise of 16 components. The highest proportion of the components extracted with acetone is 2-Pentanone, 4-hydroxy-4-methyl (19,9%, while those with n-hexane is Hexanedioic acid, dioctyl ester (65%. A. nilaparvatae showed positive response to the volatiles extracted from infested rice plant by N. lugens eggs. Therefore, the volatiles can be used as an attractant for the egg A. nilaparvatae to support rice pest management.

Comparative Proteomic Analysis of Susceptible and Resistant Rice Plants during Early Infestation by Small Brown Planthopper

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Yan Dong

2017-10-01

Full Text Available The small brown planthopper (Laodelphax striatellus Fallén, Homoptera, Delphacidae-SBPH is one of the major destructive pests of rice (Oryza sativa L.. Understanding on how rice responds to SBPH infestation will contribute to developing strategies for SBPH control. However, the response of rice plant to SBPH is poorly understood. In this study, two contrasting rice genotypes, Pf9279-4 (SBPH-resistant and 02428 (SBPH-susceptible, were used for comparative analysis of protein profiles in the leaf sheath of rice plants in responses to SBPH infestation. One hundred and thirty-two protein spots that were differentially expressed between the resistant and susceptible rice lines were identified with significant intensity differences (≥2-fold, P < 0.05 at 0, 6, and 12 h after SBPH infestation. Protein expression profile analysis in the leaf sheath of SBPH-resistant and SBPH-susceptible rice lines after SBPH infestation showed that proteins induced by SBPH feeding were involved mainly in stress response, photosynthesis, protein metabolic process, carbohydrate metabolic process, energy metabolism, cell wall-related proteins, amino acid metabolism and transcriptional regulation. Gene expression analysis of 24 differentially expressed proteins (DEPs showed that more than 50% DEPs were positively correlated with their mRNA levels. Analysis of some physiological indexes mainly involved in the removal of oxygen reactive species showed that the levels of superoxide dismutase (SOD and glutathione (GSH were considerably higher in Pf9279-4 than 02428 during SBPH infestation. The catalase (CAT activity and hydroxyl radical inhibition were lower in Pf9279-4 than 02428. Analysis of enzyme activities indicates that Pf9279-4 rice plants defend against SBPH through the activation of the pathway of the salicylic acid (SA-dependent systemic acquired resistance. In conclusion, this study provides some insights into the molecular networks involved on cellular and

Silencing of ACO decreases reproduction and energy metabolism in triazophos-treated female brown plant hoppers, Nilaparvata lugens Stål (Hemiptera: Delphacidae).

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Liu, Zong-Yu; Jiang, Yi-Ping; Li, Lei; You, Lin-Lin; Wu, You; Xu, Bin; Ge, Lin-Quan; Wu, Jin-Cai

2016-03-01

The brown plant hopper (BPH), Nilaparvata lugens Stål (Hemiptera: Delphacidae), is a major pest affecting rice in Asia, and outbreaks of this pest are closely linked to pesticide-induced stimulation of reproduction. Therefore, the BPH is a classic example of a resurgent pest. However, the effects of different genes on the regulation of pesticide-induced reproductive stimulation in the BPH are unclear. In this study, the regulatory effects of acyl-coenzyme A oxidase (ACO) on the reproduction and biochemistry of the BPH were investigated with gene silencing. The number of eggs laid per female by triazophos (TZP)+dsACO BPH females was significantly lower than those of TZP-treated (without ACO silencing) or TZP+GFP females (negative control), with the number of eggs decreasing by 30.8% (from 529.5 to 366.3) and 32.0% (from 540.5 to 366.3), respectively. The preoviposition period, oviposition period, and longevity of the TZP-treated females were also influenced by dsACO treatment. Additionally, the amounts of crude fat, protein, and some fatty acids (oleic acid, palmitic acid, linoleic acid, stearic acid, and myristoleic acid) in TZP+dsACO females were significantly lower than in TZP-treated females. Thus, ACO is one of the key genes regulating the TZP-induced stimulation of reproduction in BPH females. Copyright © 2015 Elsevier Inc. All rights reserved.

Using SPOT-5 images in rice farming for detecting BPH (Brown Plant Hopper)

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Ghobadifar, F; Wayayok, A; Shattri, M; Shafri, H

2014-01-01

Infestation of rice plant-hopper such as Brown Plant Hopper (BPH) (Nilaparvata lugens) is one of the most notable risk in rice yield in tropical areas especially in Asia. In order to use visible and infrared images to detect stress in rice production caused by BPH infestation, several remote sensing techniques have been developed. Initial recognition of pest infestation by means of remote sensing will spreads, for precision farming practice. To address this issue, detection of sheath blight in rice farming was examined by using SPOT-5 images. Specific image indices such as Normalized decrease food production costs, limit environmental hazards, and enhance natural pest control before the problem Normalized Difference Vegetation Index (NDVI), Standard difference indices (SDI) and Ratio Vegetation Index (RVI) were used for analyses using ENVI 4.8 and SPSS software. Results showed that all the indices to recognize infected plants are significant at α = 0.01. Examination of the association between the disease indices indicated that band 3 (near infrared) and band 4 (mid infrared) have a relatively high correlation. The selected indices declared better association for detecting healthy plants from diseased ones. Consequently, these sorts of indices especially NDVI could be valued as indicators for developing techniques for detecting the sheath blight of rice by using remote sensing. This infers that they are useful for crop disease detection but the spectral resolution is probably not sufficient to distinguish plants with light infections (low severity level). Using the index as an indicator can clarify the threshold for zoning the outbreaks. Quick assessment information is very useful in precision farming to practice site specific management such as pesticide application

Using SPOT-5 images in rice farming for detecting BPH (Brown Plant Hopper)

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Ghobadifar, F.; Wayayok, A.; Shattri, M.; Shafri, H.

2014-06-01

Infestation of rice plant-hopper such as Brown Plant Hopper (BPH) (Nilaparvata lugens) is one of the most notable risk in rice yield in tropical areas especially in Asia. In order to use visible and infrared images to detect stress in rice production caused by BPH infestation, several remote sensing techniques have been developed. Initial recognition of pest infestation by means of remote sensing will spreads, for precision farming practice. To address this issue, detection of sheath blight in rice farming was examined by using SPOT-5 images. Specific image indices such as Normalized decrease food production costs, limit environmental hazards, and enhance natural pest control before the problem Normalized Difference Vegetation Index (NDVI), Standard difference indices (SDI) and Ratio Vegetation Index (RVI) were used for analyses using ENVI 4.8 and SPSS software. Results showed that all the indices to recognize infected plants are significant at α = 0.01. Examination of the association between the disease indices indicated that band 3 (near infrared) and band 4 (mid infrared) have a relatively high correlation. The selected indices declared better association for detecting healthy plants from diseased ones. Consequently, these sorts of indices especially NDVI could be valued as indicators for developing techniques for detecting the sheath blight of rice by using remote sensing. This infers that they are useful for crop disease detection but the spectral resolution is probably not sufficient to distinguish plants with light infections (low severity level). Using the index as an indicator can clarify the threshold for zoning the outbreaks. Quick assessment information is very useful in precision farming to practice site specific management such as pesticide application.

Map-based Cloning and Characterization of the BPH18 Gene from Wild Rice Conferring Resistance to Brown Planthopper (BPH) Insect Pest.

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Ji, Hyeonso; Kim, Sung-Ryul; Kim, Yul-Ho; Suh, Jung-Pil; Park, Hyang-Mi; Sreenivasulu, Nese; Misra, Gopal; Kim, Suk-Man; Hechanova, Sherry Lou; Kim, Hakbum; Lee, Gang-Seob; Yoon, Ung-Han; Kim, Tae-Ho; Lim, Hyemin; Suh, Suk-Chul; Yang, Jungil; An, Gynheung; Jena, Kshirod K

2016-09-29

Brown planthopper (BPH) is a phloem sap-sucking insect pest of rice which causes severe yield loss. We cloned the BPH18 gene from the BPH-resistant introgression line derived from the wild rice species Oryza australiensis. Map-based cloning and complementation test revealed that the BPH18 encodes CC-NBS-NBS-LRR protein. BPH18 has two NBS domains, unlike the typical NBS-LRR proteins. The BPH18 promoter::GUS transgenic plants exhibited strong GUS expression in the vascular bundles of the leaf sheath, especially in phloem cells where the BPH attacks. The BPH18 proteins were widely localized to the endo-membranes in a cell, including the endoplasmic reticulum, Golgi apparatus, trans-Golgi network, and prevacuolar compartments, suggesting that BPH18 may recognize the BPH invasion at endo-membranes in phloem cells. Whole genome sequencing of the near-isogenic lines (NILs), NIL-BPH18 and NIL-BPH26, revealed that BPH18 located at the same locus of BPH26. However, these two genes have remarkable sequence differences and the independent NILs showed differential BPH resistance with different expression patterns of plant defense-related genes, indicating that BPH18 and BPH26 are functionally different alleles. These findings would facilitate elucidation of the molecular mechanism of BPH resistance and the identified novel alleles to fast track breeding BPH resistant rice cultivars.

Two ancient bacterial endosymbionts have coevolved with the planthoppers (Insecta: Hemiptera: Fulgoroidea

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Urban Julie M

2012-06-01

Full Text Available Abstract Background Members of the hemipteran suborder Auchenorrhyncha (commonly known as planthoppers, tree- and leafhoppers, spittlebugs, and cicadas are unusual among insects known to harbor endosymbiotic bacteria in that they are associated with diverse assemblages of bacterial endosymbionts. Early light microscopic surveys of species representing the two major lineages of Auchenorrhyncha (the planthopper superfamily Fulgoroidea; and Cicadomorpha, comprising Membracoidea [tree- and leafhoppers], Cercopoidea [spittlebugs], and Cicadoidea [cicadas], found that most examined species harbored at least two morphologically distinct bacterial endosymbionts, and some harbored as many as six. Recent investigations using molecular techniques have identified multiple obligate bacterial endosymbionts in Cicadomorpha; however, much less is known about endosymbionts of Fulgoroidea. In this study, we present the initial findings of an ongoing PCR-based survey (sequencing 16S rDNA of planthopper-associated bacteria to document endosymbionts with a long-term history of codiversification with their fulgoroid hosts. Results Results of PCR surveys and phylogenetic analyses of 16S rDNA recovered a monophyletic clade of Betaproteobacteria associated with planthoppers; this clade included Vidania fulgoroideae, a recently described bacterium identified in exemplars of the planthopper family Cixiidae. We surveyed 77 planthopper species representing 18 fulgoroid families, and detected Vidania in 40 species (representing 13 families. Further, we detected the Sulcia endosymbiont (identified as an obligate endosymbiont of Auchenorrhyncha in previous studies in 30 of the 40 species harboring Vidania. Concordance of the Vidania phylogeny with the phylogeny of the planthopper hosts (reconstructed based on sequence data from five genes generated from the same insect specimens from which the bacterial sequences were obtained was supported by statistical tests of

Two ancient bacterial endosymbionts have coevolved with the planthoppers (Insecta: Hemiptera: Fulgoroidea).

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Urban, Julie M; Cryan, Jason R

2012-06-14

Members of the hemipteran suborder Auchenorrhyncha (commonly known as planthoppers, tree- and leafhoppers, spittlebugs, and cicadas) are unusual among insects known to harbor endosymbiotic bacteria in that they are associated with diverse assemblages of bacterial endosymbionts. Early light microscopic surveys of species representing the two major lineages of Auchenorrhyncha (the planthopper superfamily Fulgoroidea; and Cicadomorpha, comprising Membracoidea [tree- and leafhoppers], Cercopoidea [spittlebugs], and Cicadoidea [cicadas]), found that most examined species harbored at least two morphologically distinct bacterial endosymbionts, and some harbored as many as six. Recent investigations using molecular techniques have identified multiple obligate bacterial endosymbionts in Cicadomorpha; however, much less is known about endosymbionts of Fulgoroidea. In this study, we present the initial findings of an ongoing PCR-based survey (sequencing 16S rDNA) of planthopper-associated bacteria to document endosymbionts with a long-term history of codiversification with their fulgoroid hosts. Results of PCR surveys and phylogenetic analyses of 16S rDNA recovered a monophyletic clade of Betaproteobacteria associated with planthoppers; this clade included Vidania fulgoroideae, a recently described bacterium identified in exemplars of the planthopper family Cixiidae. We surveyed 77 planthopper species representing 18 fulgoroid families, and detected Vidania in 40 species (representing 13 families). Further, we detected the Sulcia endosymbiont (identified as an obligate endosymbiont of Auchenorrhyncha in previous studies) in 30 of the 40 species harboring Vidania. Concordance of the Vidania phylogeny with the phylogeny of the planthopper hosts (reconstructed based on sequence data from five genes generated from the same insect specimens from which the bacterial sequences were obtained) was supported by statistical tests of codiversification. Codiversification tests also

Migration of rice planthoppers and their vectored re-emerging and novel rice viruses in East Asia.

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Otuka, Akira

2013-10-28

This review examines recent studies of the migration of three rice planthoppers, Laodelphax striatellus, Sogatella furcifera, and Nilaparvata lugens, in East Asia. Laodelphax striatellus has recently broken out in Jiangsu province, eastern China. The population density in the province started to increase in the early 2000s and peaked in 2004. In 2005, Rice stripe virus (RSV) viruliferous rate of L. striatellus peaked at 31.3%. Since then, rice stripe disease spread severely across the whole province. Due to the migration of the RSV vectors, the rice stripe disease spread to neighboring countries Japan and Korea. An overseas migration of L. striatellus that occurred in 2008 was analyzed, when a slow-moving cold vortex, a type of low pressure system, reached western Japan from Jiangsu, carrying the insects into Japan. Subsequently the rice stripe diseases struck these areas in Japan severely. In Korea, similar situations occurred in 2009, 2011, and 2012. Their migration sources were also estimated to be in Jiangsu by backward trajectory analysis. Rice black-streaked dwarf virus, whose vector is L. striatellus, has recently re-emerged in eastern China, and the evidence for overseas migrations of the virus, just like the RSV's migrations, has been given. A method of predicting the overseas migration of L. striatellus has been developed by Japanese, Chinese, and Korean institutes. An evaluation of the prediction showed that this method properly predicted migration events that occurred in East Asia from 2008 to 2011. Southern rice black-streaked dwarf virus (SRBSDV) was first found in Guangdong province. Its vector is S. furcifera. An outbreak of SRBSDV occurred in southern China in 2009 and spread to Vietnam the same year. This disease and virus were also found in Japan in 2010. The epidemic triggered many migration studies to investigate concrete spring-summer migration routes in China, and the addition of migration sources for early arrivals in Guangdong and Guangxi

Susceptibility of Sogatella furcifera and Laodelphax striatellus (Hemiptera: Delphacidae) to Six Insecticides in China.

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Zhang, Kai; Zhang, Wei; Zhang, Shuai; Wu, Shun-Fan; Ban, Lan-Feng; Su, Jian-Ya; Gao, Cong-Fen

2014-10-01

The whitebacked planthopper, Sogatella furcifera (Horváth), and small brown planthopper, Laodelphax striatellus (Fallén), both are important crop pests throughout China, especially in rice. Application of chemical insecticides is the major control practice. Consequently, insecticide resistance has become an urgent issue. In this study, resistance levels to six conventional insecticides were evaluated for these two species collected from major occurring areas of China. Additionally, imidacloprid- (resistance ratio [RR] = 10.4-fold) and buprofezin (RR = 15.1-fold)-resistant strains of whitebacked planthopper were obtained through laboratory selections for cross-resistance profiling and synergism assessment to understand resistance mechanisms. The results showed that all tested populations of both species exhibited low to high levels of resistance to chlorpyrifos, while remaining susceptible to thiamethoxam. Three of the 14 whitebacked planthopper populations showed low to moderate resistance to imidacloprid, while all small brown planthopper populations reminded susceptible. All small brown planthopper and whitebacked planthopper (except one) populations showed at least moderate resistance (RR = 10.1-271.1) to buprofezin. All small brown planthopper populations remained susceptible to pymetrozine and nitenpyram, and all whitebacked planthopper populations remained susceptible to isoprocarb. The imidacloprid-resistant whitebacked planthopper strain showed no significant cross-resistance to other tested insecticides. However, the buprofezin-resistant strain exhibited a low-level cross-resistance (CR = 3.1) to imidacloprid. Piperonyl butoxide, triphenyl phosphate, and diethylmaleate displayed no synergism effect on the resistant whitebacked planthopper strains. © 2014 Entomological Society of America.

Cross-resistance of bisultap resistant strain of Nilaparvata lugens and its biochemical mechanism.

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Ling, Shanfeng; Zhang, Runjie

2011-02-01

The resistant (R) strain of the planthopper Nilaparvata lugens (Stål) selected for bisultap resistance displayed 7.7-fold resistance to bisultap and also had cross-resistance to nereistoxin (monosultap, thiocyclam, and cartap), chlorpyrifos, dimethoate, and malathion but no cross-resistance to buprofezin, imidacloprid, and fipronil. To find out the biochemical mechanism of resistance to bisultap, biochemical assay was done. The results showed that cytochrome P450 monooxygenases (P450) activity in R strain was 2.71-fold that in susceptible strain (S strain), in which the changed activity for general esterase (EST) was 1.91 and for glutathione S-transferases only 1.32. Piperonyl butoxide (PBO) could significantly inhibit P450 activity (percentage of inhibition [PI]: 37.31%) in the R strain, with ESTs PI = 16.04% by triphenyl phosphate (TPP). The results also demonstrated that diethyl maleate had no synergism with bisultap. However, PBO displayed significant synergism in three different strains, and the synergism increased with resistance (S strain 1.42, Lab strain, 2.24 and R strain, 3.23). TPP also showed synergism for three strains, especially in R strain (synergistic ratio = 2.47). An in vitro biochemical study and in vivo synergistic study indicated that P450 might be play important role in the biochemical mechanism of bisultap resistance and that esterase might be the important factor of bisultap resistance. Acetylcholinesterase (AChE) insensitivity play important role in bisultap resistance. We suggest that buprofezin, imidacloprid, and fipronil could be used in resistance management programs for N. lugens via alternation and rotation with bisultap.

Pendugaan Gen Bph1, Bph2, Bph3, Dan Bph4 Pada Galur-galur Padi Terpilih Tahan Hama Wereng Batang Cokelat (Nilaparvata Lugens[Stål])

OpenAIRE

Damayanti, Diani; Utami, Dwinita W

2014-01-01

Pests are major constraints to increasingrice production and brown planthoppers/BPH (Nilaparvatalugens [Stål]) is one of the major pests of rice plant.Resistance cultivar is one of the strategies for BPHmanagement. The objective of this research was to analyzethe Bph1, bph2, Bph3, and bph4 gene existence on theselected rice lines using the molecular markers. Thephenotype of the rice lines were tested based on theirresponse to BPH population collected from West Java andCental Java. Molecular m...

Comparative transcriptome analysis of two rice varieties in response to rice stripe virus and small brown planthoppers during early interaction.

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Wenjing Zheng

Full Text Available Rice stripe, a virus disease, transmitted by a small brown planthopper (SBPH, has greatly reduced production of japonica rice in East Asia, especially in China. Although we have made great progress in mapping resistance genes, little is known about the mechanism of resistance. By de novo transcriptome assembling, we gained sufficient transcript data to analyze changes in gene expression of early interaction in response to SBPH and RSV infection in rice. Respectively 648 and 937 DEGs were detected from the disease-resistant (Liaonong 979 and the susceptible (Fengjin varieties, most of which were up-regulated. We found 37 genes related to insect resistance, which mainly included genes for jasmonate-induced protein, TIFY protein, lipoxygenase, as well as trypsin inhibitor genes and transcription factor genes. In the interaction process between RSV and rice, 87 genes were thought to be related to RSV resistance; these primarily included 12 peroxidase biosynthesis genes, 12 LRR receptor-like protein kinase genes, 6 genes coding pathogenesis-related proteins, 4 glycine-rich cell wall structural protein genes, 2 xyloglucan hydrolase genes and a cellulose synthase. The results indicate that the rice-pathogen interaction happened both in disease-resistant and susceptible varieties, and some genes related to JA biosynthesis played key roles in the interaction between SBPHs and rice. When rice was infected by RSV a hypersensitive reaction (HR in the disease-resistant variety was suppressed, which resulted from an increase in peroxidase expression and down-regulation of LRR receptor-like protein kinase and pathogenesis-related proteins, while, the changes of peroxidase biosynthesis, glycine-rich cell wall structural protein, cellulose synthase and xyloglucan endotransglucosylase/hydrolase could lead to the strengthening of physical barriers of rice, which may be an important resistance mechanism to RSV in rice.

Comparative transcriptome analysis of two rice varieties in response to rice stripe virus and small brown planthoppers during early interaction.

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Zheng, Wenjing; Ma, Li; Zhao, Jiaming; Li, Zhiqiang; Sun, Fuyu; Lu, Xiaochun

2013-01-01

Rice stripe, a virus disease, transmitted by a small brown planthopper (SBPH), has greatly reduced production of japonica rice in East Asia, especially in China. Although we have made great progress in mapping resistance genes, little is known about the mechanism of resistance. By de novo transcriptome assembling, we gained sufficient transcript data to analyze changes in gene expression of early interaction in response to SBPH and RSV infection in rice. Respectively 648 and 937 DEGs were detected from the disease-resistant (Liaonong 979) and the susceptible (Fengjin) varieties, most of which were up-regulated. We found 37 genes related to insect resistance, which mainly included genes for jasmonate-induced protein, TIFY protein, lipoxygenase, as well as trypsin inhibitor genes and transcription factor genes. In the interaction process between RSV and rice, 87 genes were thought to be related to RSV resistance; these primarily included 12 peroxidase biosynthesis genes, 12 LRR receptor-like protein kinase genes, 6 genes coding pathogenesis-related proteins, 4 glycine-rich cell wall structural protein genes, 2 xyloglucan hydrolase genes and a cellulose synthase. The results indicate that the rice-pathogen interaction happened both in disease-resistant and susceptible varieties, and some genes related to JA biosynthesis played key roles in the interaction between SBPHs and rice. When rice was infected by RSV a hypersensitive reaction (HR) in the disease-resistant variety was suppressed, which resulted from an increase in peroxidase expression and down-regulation of LRR receptor-like protein kinase and pathogenesis-related proteins, while, the changes of peroxidase biosynthesis, glycine-rich cell wall structural protein, cellulose synthase and xyloglucan endotransglucosylase/hydrolase could lead to the strengthening of physical barriers of rice, which may be an important resistance mechanism to RSV in rice.

The Chloroplast-Localized Phospholipases D α4 and α5 Regulate Herbivore-Induced Direct and Indirect Defenses in Rice1[C][W

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Qi, Jinfeng; Zhou, Guoxin; Yang, Lijuan; Erb, Matthias; Lu, Yanhua; Sun, Xiaoling; Cheng, Jiaan; Lou, Yonggen

2011-01-01

The oxylipin pathway is of central importance for plant defensive responses. Yet, the first step of the pathway, the liberation of linolenic acid following induction, is poorly understood. Phospholipases D (PLDs) have been hypothesized to mediate this process, but data from Arabidopsis (Arabidopsis thaliana) regarding the role of PLDs in plant resistance have remained controversial. Here, we cloned two chloroplast-localized PLD genes from rice (Oryza sativa), OsPLDα4 and OsPLDα5, both of which were up-regulated in response to feeding by the rice striped stem borer (SSB) Chilo suppressalis, mechanical wounding, and treatment with jasmonic acid (JA). Antisense expression of OsPLDα4 and -α5 (as-pld), which resulted in a 50% reduction of the expression of the two genes, reduced elicited levels of linolenic acid, JA, green leaf volatiles, and ethylene and attenuated the SSB-induced expression of a mitogen-activated protein kinase (OsMPK3), a lipoxygenase (OsHI-LOX), a hydroperoxide lyase (OsHPL3), as well as a 1-aminocyclopropane-1-carboxylic acid synthase (OsACS2). The impaired oxylipin and ethylene signaling in as-pld plants decreased the levels of herbivore-induced trypsin protease inhibitors and volatiles, improved the performance of SSB and the rice brown planthopper Nilaparvata lugens, and reduced the attractiveness of plants to a larval parasitoid of SSB, Apanteles chilonis. The production of trypsin protease inhibitors in as-pld plants could be partially restored by JA, while the resistance to rice brown planthopper and SSB was restored by green leaf volatile application. Our results show that phospholipases function as important components of herbivore-induced direct and indirect defenses in rice. PMID:21984727

The chloroplast-localized phospholipases D α4 and α5 regulate herbivore-induced direct and indirect defenses in rice.

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Qi, Jinfeng; Zhou, Guoxin; Yang, Lijuan; Erb, Matthias; Lu, Yanhua; Sun, Xiaoling; Cheng, Jiaan; Lou, Yonggen

2011-12-01

The oxylipin pathway is of central importance for plant defensive responses. Yet, the first step of the pathway, the liberation of linolenic acid following induction, is poorly understood. Phospholipases D (PLDs) have been hypothesized to mediate this process, but data from Arabidopsis (Arabidopsis thaliana) regarding the role of PLDs in plant resistance have remained controversial. Here, we cloned two chloroplast-localized PLD genes from rice (Oryza sativa), OsPLDα4 and OsPLDα5, both of which were up-regulated in response to feeding by the rice striped stem borer (SSB) Chilo suppressalis, mechanical wounding, and treatment with jasmonic acid (JA). Antisense expression of OsPLDα4 and -α5 (as-pld), which resulted in a 50% reduction of the expression of the two genes, reduced elicited levels of linolenic acid, JA, green leaf volatiles, and ethylene and attenuated the SSB-induced expression of a mitogen-activated protein kinase (OsMPK3), a lipoxygenase (OsHI-LOX), a hydroperoxide lyase (OsHPL3), as well as a 1-aminocyclopropane-1-carboxylic acid synthase (OsACS2). The impaired oxylipin and ethylene signaling in as-pld plants decreased the levels of herbivore-induced trypsin protease inhibitors and volatiles, improved the performance of SSB and the rice brown planthopper Nilaparvata lugens, and reduced the attractiveness of plants to a larval parasitoid of SSB, Apanteles chilonis. The production of trypsin protease inhibitors in as-pld plants could be partially restored by JA, while the resistance to rice brown planthopper and SSB was restored by green leaf volatile application. Our results show that phospholipases function as important components of herbivore-induced direct and indirect defenses in rice.

Insect fungi for the control of brown planthopper Nilaparvata lugens, and Malayan rice bug, Scotinophara coarctata

NARCIS (Netherlands)

Rombach, M.C.

1987-01-01

Introduction : Many potential pest organisms are normally kept at densities below damage thresholds by naturally occurring natural enemies in virtually all agricultural crops. This natural control can be enhanced by introduction of new biological agents

Aboveground herbivory by the brown planthopper (Nilaparvata lugens) affects soil nematode communities under different rice varieties

NARCIS (Netherlands)

Liu, M.; Huang, J.; Chen, X.; Wang, F.; Ge, C.; Su, Y.; Shao, B.; Tang, Y.; Li, H.

2009-01-01

Interactions between aboveground–belowground communities play an important role in regulating terrestrial ecological processes; however, the interactions between rice varieties, herbivory and the soil community are often ignored. A pot experiment with a full 2×2 factorial design was conducted to

No cross-resistance between imidacloprid and pymetrozine in the brown planthopper: status and mechanisms.

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Yang, Yuanxue; Huang, Lixin; Wang, Yunchao; Zhang, Yixi; Fang, Siqi; Liu, Zewen

2016-06-01

Cross-resistance between insecticides, especially from different groups, can be extremely unpredictable, and it has been a serious concern in pest control. Pymetrozine has been widely used to control Nilaparvata lugens with the suspension of imidacloprid for the resistance, and N. lugens has showed obvious pymetrozine resistance in recent years. To investigate the possible cross-resistance between imidacloprid and pymetrozine is very important to avoid the adverse effects on resistance development and pest control. Bioassays of two field populations in five consecutive years showed that imidacloprid resistance decreased greatly, while pymetrozine resistance increased significantly. The synergist piperonyl butoxide (PBO) could synergize both imidacloprid and pymetrozine in all field populations, which indicated the importance of P450s in the resistance to two insecticides. Imidacloprid resistance was reported to be associated with two P450s, CYP6AY1 and CYP6ER1, which could metabolize imidacloprid efficiently. However, the recombinant proteins of these two P450s did not show any enzymatic activity to metabolize pymetrozine. The pymetrozine susceptibility did not change when CYP6AY1 and CYP6ER1 mRNA levels were reduced by RNA interference (RNAi), although which could obviously decrease imidacloprid resistance. In vivo and in vitro studies provided evidences to demonstrate that there was no cross-resistance between imidacloprid and pymetrozine in N. lugens, which was different from the findings in Bemisia tabaci. Copyright © 2015. Published by Elsevier Inc.

Development of 25 near-isogenic lines (NILs) with ten BPH resistance genes in rice (Oryza sativa L.): production, resistance spectrum, and molecular analysis.

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Jena, Kshirod K; Hechanova, Sherry Lou; Verdeprado, Holden; Prahalada, G D; Kim, Sung-Ryul

2017-11-01

A first set of 25 NILs carrying ten BPH resistance genes and their pyramids was developed in the background of indica variety IR24 for insect resistance breeding in rice. Brown planthopper (Nilaparvata lugens Stal.) is one of the most destructive insect pests in rice. Development of near-isogenic lines (NILs) is an important strategy for genetic analysis of brown planthopper (BPH) resistance (R) genes and their deployment against diverse BPH populations. A set of 25 NILs with 9 single R genes and 16 multiple R gene combinations consisting of 11 two-gene pyramids and 5 three-gene pyramids in the genetic background of the susceptible indica rice cultivar IR24 was developed through marker-assisted selection. The linked DNA markers for each of the R genes were used for foreground selection and confirming the introgressed regions of the BPH R genes. Modified seed box screening and feeding rate of BPH were used to evaluate the spectrum of resistance. BPH reaction of each of the NILs carrying different single genes was variable at the antibiosis level with the four BPH populations of the Philippines. The NILs with two- to three-pyramided genes showed a stronger level of antibiosis (49.3-99.0%) against BPH populations compared with NILs with a single R gene NILs (42.0-83.5%) and IR24 (10.0%). Background genotyping by high-density SNPs markers revealed that most of the chromosome regions of the NILs (BC 3 F 5 ) had IR24 genome recovery of 82.0-94.2%. Six major agronomic data of the NILs showed a phenotypically comparable agronomic performance with IR24. These newly developed NILs will be useful as new genetic resources for BPH resistance breeding and are valuable sources of genes in monitoring against the emerging BPH biotypes in different rice-growing countries.

A neurotropic route for Maize mosaic virus (Rhabdoviridae) in its planthopper vector Peregrinus maidis.

Science.gov (United States)

Ammar, El-Desouky; Hogenhout, Saskia A

2008-01-01

To investigate the dissemination route of Maize mosaic virus (MMV, Rhabdoviridae) in its planthopper vector Peregrinus maidis (Delphacidae, Hemiptera), temporal and spatial distribution of MMV was studied by immunofluorescence confocal laser scanning microscopy following 1-week acquisition feeding of planthoppers on infected plants. MMV was detected 1-week post first access to diseased plants (padp) in the midgut and anterior diverticulum, 2-week padp in the esophagus, nerves, nerve ganglia and visceral muscles, and 3-week padp in hemocytes, tracheae, salivary glands and other tissues. MMV is neurotropic in P. maidis; infection was more extensive in the nervous system compared to other tissues. A significantly higher proportion of planthoppers had infected midguts (28.1%) compared to those with infected salivary glands (20.4%) or to those that transmitted MMV (15.7%), suggesting the occurrence of midgut and salivary gland barriers to MMV transmission in P. maidis. In this planthopper, the esophagus and anterior diverticulum are located between the compound ganglionic mass and the salivary glands. We postulate that MMV may overcome transmission barriers in P. maidis by proceeding from the midgut to the anterior diverticulum and esophagus, and from these to the salivary glands via the nervous system: a neurotropic route similar to that of some vertebrate-infecting rhabdoviruses.

Prioritizing plant defence over growth through WRKY regulation facilitates infestation by non-target herbivores

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Li, Ran; Zhang, Jin; Li, Jiancai; Zhou, Guoxin; Wang, Qi; Bian, Wenbo; Erb, Matthias; Lou, Yonggen

2015-01-01

Plants generally respond to herbivore attack by increasing resistance and decreasing growth. This prioritization is achieved through the regulation of phytohormonal signaling networks. However, it remains unknown how this prioritization affects resistance against non-target herbivores. In this study, we identify WRKY70 as a specific herbivore-induced, mitogen-activated protein kinase-regulated rice transcription factor that physically interacts with W-box motifs and prioritizes defence over growth by positively regulating jasmonic acid (JA) and negatively regulating gibberellin (GA) biosynthesis upon attack by the chewing herbivore Chilo suppressalis. WRKY70-dependent JA biosynthesis is required for proteinase inhibitor activation and resistance against C. suppressalis. In contrast, WRKY70 induction increases plant susceptibility against the rice brown planthopper Nilaparvata lugens. Experiments with GA-deficient rice lines identify WRKY70-dependent GA signaling as the causal factor in N. lugens susceptibility. Our study shows that prioritizing defence over growth leads to a significant resistance trade-off with important implications for the evolution and agricultural exploitation of plant immunity. DOI: http://dx.doi.org/10.7554/eLife.04805.001 PMID:26083713

OsWRKY53, a versatile switch in regulating herbivore-induced defense responses in rice

Science.gov (United States)

Hu, Lingfei; Ye, Meng; Li, Ran; Lou, Yonggen

2016-01-01

ABSTRACT WRKY proteins, which belong to a large family of plant-specific transcription factors, play important roles in plant defenses against pathogens and herbivores by regulating defense-related signaling pathways. Recently, a rice WRKY transcription factor OsWRKY53 has been reported to function as a negative feedback modulator of OsMPK3/OsMPK6 and thereby to control the size of the investment a rice plant makes to defend against a chewing herbivore, the striped stem borer Chilo suppressalis. We investigated the performance of a piecing-sucking herbivore, the brown planthopper (BPH) Nilaparvata lugens, on transgenic plants that silence or overexpress OsWRKY53, and found that OsWRKY53 activates rice defenses against BPH by activating an H2O2 burst and suppressing ethylene biosynthesis. These findings suggest that OsWRKY53 functions not only as a regulator of plants' investment in specific defenses, but also as a switch to initiate new defenses against other stresses, highlighting the versatility and importance of OsWRKY53 in herbivore-induced plant defenses. PMID:27031005

Susceptibility of Different Populations of Nilaparvata lugens from Major Rice Growing Areas of Karnataka, India to Different Groups of Insecticides

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Y.S. BASANTH

2013-09-01

Full Text Available Susceptibility to insecticides was investigated by collecting field populations of brown planthopper from different locations of southern Karnataka, India (Gangavati, Kathalagere, Kollegala, Soraba and Mandya. All the field populations differed in their susceptibility to insecticides. In general, Soraba and Mandya populations were more susceptible to insecticides compared to Gangavati and Kathalagere populations. The resistance ratios varied greatly among the populations viz., chlorpyriphos (1.13- to 16.82-fold, imidacloprid (0.53- to 13.50-fold, acephate (1.34- to 5.32-fold, fipronil (1.13- to 4.06-fold, thiamethoxam (1.01- to 2.19-fold, clothianidin (1.92- to 4.86-fold, dinotefuran (0.82- to 2.22-fold, buprofezin (1.06- to 5.43-fold and carbofuran (0.41- to 2.17-fold. The populations from Gangavati, Kathalagere and Kollegala exhibited higher resistance to some of the old insecticides and low resistance to new molecules.

An injury equivalency system for establishing a common economic threshold for three species of rice planthoppers (Hemiptera: Delphacidae) in Taiwan.

Science.gov (United States)

Huang, Shou-Horng; Chen, Ching-Huan; Chen, Chiou-Nan; Wu, Wen-Jer

2013-04-01

The economic threshold (ET) for multiple pest species that share the same injury type on host plants (feeding guild) has been proposed for decision-making in integrated management framework of many defoliating insect pests. However, only a few consider agricultural pests with sucking mouthparts. This study presents the first injury equivalency system for the feeding guild made up of three rice (Oryza sativa L.) planthopper (Hemiptera: Delphacidae) species--Nilaparvata lugens (Stål), Sogatella furcifera (Harváth), and Laodelphax striatellus (Fallén)--by using relative amount of honeydew excretion of each species. The intraspecific injury equivalent coefficient was determined; this coefficient provides an exchange rate for different developmental stages in a species. N. lugens was chosen as the standard species to obtain interspecific injury equivalents for other individuals in the guild, allowing estimates of total guild injury feasible. For extension purposes, the injury equivalency was simplified by pooling all nymphs and adults in the guild to mitigate the potential confusion resulting from uncertainty of instars or wing form. A matrix of ETs established on previous studies and incorporating changes of management cost and rice price was used and served as a control decision guide for the guild samples. The validity of the proposed injury equivalency system was tested using several field data sets, and the results are generally promising and meaningfully elevate the accuracy of estimating combined injury and damage to rice, suggesting that the proposed system is a better integrated pest management decision-making system compared with conventional practices.

Ecological Fitness of Non-vector Planthopper Sogatella furcifera on Rice Plants Infected with Rice Black Streaked Dwarf Virus

Directory of Open Access Journals (Sweden)

Xiao-chan HE

2012-12-01

Full Text Available We evaluated the effects of rice black streak dwarf virus (RBSDV-infested rice plants on the ecological parameters and its relevant defensive and detoxification enzymes of white-backed planthopper (WBPH in laboratory for exploring the relationship between RBSDV and the non-vector planthopper. The results showed that nymph survival rate, female adult weight and fecundity, and egg hatchability of WBPH fed on RBSDV-infested rice plants did not markedly differ from those on healthy plants, whereas the female adult longevity and egg duration significantly shortened on diseased plants. Furthermore, significantly higher activities of defensive enzymes (dismutase, catalase and peroxidase and detoxification enzymes (acetylcholinesterase, carboxylesterase and glutathione S-transferase were found in WBPH adults fed on infected plants. Results implied that infestation by RBSDV increased the ecological fitness of non-vector planthopper population.

On design of sensor nodes in the rice planthopper monitoring system based on the internet of things

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Wang, Ke Qiang; Cai, Ken

2011-02-01

Accurate records and prediction of the number of the rice planthopper's outbreaks and the environmental information of farmland are effective measures to control pests' damages. On the other hand, a new round of technological revolution from the Internet to the Internet of things is taking place in the field of information. The application of the Internet of things in rice planthopper and environmental online monitoring is an effective measure to solve problems existing in the present wired sensor monitoring technology. Having described the general framework of wireless sensor nodes in the Internet of things in this paper, the software and hardware design schemes of wireless sensor nodes are proposed, combining the needs of rice planthopper and environmental monitoring. In these schemes, each module's design and key components' selection are both aiming to the characteristics of the Internet of things, so it has a strong practical value.

Insect symbiosis: derivation of yeast-like endosymbionts within an entomopathogenic filamentous lineage.

Science.gov (United States)

Suh, S O; Noda, H; Blackwell, M

2001-06-01

Yeast-like endosymbionts (YLSs) of insects often are restricted to specific hosts and are essential to the host's survival. For example, in planthoppers (Homoptera: Delphacidae), endosymbionts function in sterol utilization and nitrogen recycling for the hosts. Our study, designed to investigate evolutionary changes in the YLS lineage involved in the planthopper association, strongly suggests an origin of the YLSs from within the filamentous ascomycetes (Euascomycetes), not the true yeasts (Saccharomycetes), as their morphology might indicate. During divergence of the planthopper YLSs, dramatic changes would have occurred in the insect-fungus interaction and the fungal morphology that have previously been undescribed in filamentous ascomycetes. Phylogenetic trees were based on individual and combined data sets of 2.6 kb of the nuclear small- and large-subunit ribosomal RNA genes for YLSs from three rice planthoppers (Laodelphax striatellus, Nilaparvata lugens, and Sogatella furcifera) compared with 56 other fungi. Parsimony analysis placed the planthopper YLSs within Cordyceps (Euascomycetes: Hypocreales: Clavicipitaceae), a genus of filamentous insects and a few fungal pathogenic ascomycetes. Another YLS species restricted to the aphid Hamiltonaphis styraci (Homoptera: Aphididae) was a sister taxon to the planthopper YLSS: Filamentous insect pathogens (Metarhizium and Beauveria) specific to the same species of insect hosts as the YLSs also formed lineages within the Clavicipitaceae, but these were distinct from the clade comprising YLS species. Trees constrained to include the YLSs in families of the Hypocreales other than the Clavicipitaceae were rejected by the Kishino-Hasegawa test. In addition, the results of this study support a hypothesis of two independent origins of insect-associated YLSs from among filamentous ascomycetes: the planthopper YLSs in the Clavicipitaceae and the YLSs associated with anobiid beetles (Symbiotaphrina species). Several lineages of

Transgenic plants expressing the AaIT/GNA fusion protein show increased resistance and toxicity to both chewing and sucking pests.

Science.gov (United States)

Liu, Shu-Min; Li, Jie; Zhu, Jin-Qi; Wang, Xiao-Wei; Wang, Cheng-Shu; Liu, Shu-Sheng; Chen, Xue-Xin; Li, Sheng

2016-04-01

The adoption of pest-resistant transgenic plants to reduce yield losses and decrease pesticide use has been successful. To achieve the goal of controlling both chewing and sucking pests in a given transgenic plant, we generated transgenic tobacco, Arabidopsis, and rice plants expressing the fusion protein, AaIT/GNA, in which an insecticidal scorpion venom neurotoxin (Androctonus australis toxin, AaIT) is fused to snowdrop lectin (Galanthus nivalis agglutinin, GNA). Compared with transgenic tobacco and Arabidopsis plants expressing AaIT or GNA, transgenic plants expressing AaIT/GNA exhibited increased resistance and toxicity to one chewing pest, the cotton bollworm, Helicoverpa armigera. Transgenic tobacco and rice plants expressing AaIT/GNA showed increased resistance and toxicity to two sucking pests, the whitefly, Bemisia tabaci, and the rice brown planthopper, Nilaparvata lugens, respectively. Moreover, in the field, transgenic rice plants expressing AaIT/GNA exhibited a significant improvement in grain yield when infested with N. lugens. This study shows that expressing the AaIT/GNA fusion protein in transgenic plants can be a useful approach for controlling pests, particularly sucking pests which are not susceptible to the toxin in Bt crops. © 2015 Institute of Zoology, Chinese Academy of Sciences.

Activation of the TOR Signalling Pathway by Glutamine Regulates Insect Fecundity.

Science.gov (United States)

Zhai, Yifan; Sun, Zhongxiang; Zhang, Jianqing; Kang, Kui; Chen, Jie; Zhang, Wenqing

2015-05-29

The target of rapamycin (TOR) positively controls cell growth in response to nutrients such as amino acids. However, research on the specific nutrients sensed by TOR is limited. Glutamine (Gln), a particularly important amino acid involved in metabolism in organisms, is synthesised and catalysed exclusively by glutamine synthetase (GS), and our previous studies have shown that Gln may regulate fecundity in vivo levels of the brown planthopper (BPH) Nilaparvata lugens. Until now, it has remained unclear whether Gln activates or inhibits the TOR signalling pathway. Here, we performed the combined analyses of iTRAQ (isobaric tags for relative and absolute quantification) and DGE (tag-based digital gene expression) data in N. lugens at the protein and transcript levels after GS RNAi, and we found that 52 pathways overlap, including the TOR pathway. We further experimentally demonstrate that Gln activates the TOR pathway by promoting the serine/threonine protein kinase AKT and inhibiting the 5'AMP-activated protein kinase AMPK phosphorylation activity in the pest. Furthermore, TOR regulates the fecundity of N. lugens probably by mediating vitellogenin (Vg) expression. This work is the first report that Gln activates the TOR pathway in vivo.

Glutathione S-Transferase of Brown Planthoppers (Nilaparvata lugens) Is Essential for Their Adaptation to Gramine-Containing Host Plants

OpenAIRE

Sun, Xiao-Qin; Zhang, Mao-Xin; Yu, Jing-Ya; Jin, Yu; Ling, Bing; Du, Jin-Ping; Li, Gui-Hua; Qin, Qing-Ming; Cai, Qing-Nian

2013-01-01

Plants have evolved complex processes to ward off attacks by insects. In parallel, insects have evolved mechanisms to thwart these plant defenses. To gain insight into mechanisms that mediate this arms race between plants and herbivorous insects, we investigated the interactions between gramine, a toxin synthesized by plants of the family Gramineae, and glutathione S transferase (GST), an enzyme found in insects that is known to detoxify xenobiotics. Here, we demonstrate that rice (Oryza sati...

Symbiont-mediated adaptation by planthoppers and leafhoppers to resistant rice varieties

NARCIS (Netherlands)

Ferrater, J.B.; Jong, de P.W.; Dicke, M.; Chen, Y.H.; Horgan, F.G.

2013-01-01

For over 50 years, host plant resistance has been the principal focus of public research to reduce planthopper and leafhopper damage to rice in Asia. Several resistance genes have been identified from native varieties and wild rice species, and some of these have been incorporated into high-yielding

Migration of rice planthoppers and their vectored re-emerging and novel rice viruses in East Asia

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Akira eOtuka

2013-10-01

Full Text Available This review examines recent studies of the migration of three rice planthoppers, Laodelphax striatellus, Sogatella furcifera, and Nilaparvata lugens, in East Asia. Laodelphax striatellus has recently broken out in Jiangsu province, eastern China. The population density in the province started to increase in the early 2000s and peaked in 2004. In 2005, Rice stripe virus (RSV viruliferous rate of L. striatellus peaked at 31.3%. Since then, rice stripe disease spread severely across the whole province. Due to the migration of the RSV vectors, the rice stripe disease spread to neighboring countries Japan and Korea. An overseas migration of L. striatellus that occurred in 2008 was analyzed, when a slow-moving cold vortex, a type of low pressure system, reached western Japan from Jiangsu, carrying the insects into Japan. Subsequently the rice stripe diseases struck these areas in Japan severely. In Korea, similar situations occurred in 2009, 2011, and 2012. Their migration sources were also estimated to be in Jiangsu by backward trajectory analysis. Rice black-streaked dwarf virus, whose vector is L. striatellus, has recently re-emerged in eastern China, and the evidence for overseas migrations of the virus, just like the RSV’s migrations, has been given. A method of predicting the overseas migration of L. striatellus has been developed by Japanese, Chinese, and Korean institutes. An evaluation of the prediction showed that this method properly predicted migration events that occurred in East Asia from 2008 to 2011. Southern rice black-streaked dwarf virus (SRBSDV was first found in Guangdong province. Its vector is S. furcifera. An outbreak of SRBSDV occurred in southern China in 2009 and spread to Vietnam the same year. This disease and virus were also found in Japan in 2010. The epidemic triggered many migration studies to investigate concrete spring-summer migration routes in China, and the addition of migration sources for early arrivals in

The Hawaiian cave planthoppers (Homoptera: Fulgoroidea: Cixiidae - A model for rapid subterranean speciation?

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Hannelore Hoch

1997-01-01

Full Text Available After the successful colonization of a single ancestral species in the Hawaiian Islands, planthoppers of the cixiid genus Oliarus underwent intensive adaptive radiation resulting in 80 described endemic species. Oliarus habitats range from montaneous rain forests to dry coastal biotopes and subterranean environments. At least 7 independant evolutionary lines represented by different species have adapted to lava tubes on Molokai (1, Maui (3, and Hawaii Island (3. Behavioral and morphological studies on one of these evolutionary lines on Hawaii Island, the blind, flight- and pigmentless Oliarus polyphentus have provided evidence for reproductive isolation between allopatric populations which may in fact be separate species. Significant differences in song parameters were observed even between populations from neighbouring lava tubes, although the planthoppers are capable of underground migration through the voids and cracks of the mesocavernous rock system which is extant in young basalt: after a little more than 20 years, lava tubes within the Mauna Ulu 1974 flow had been colonized by O. ‘polyphenius” individuals, most probably originating from a near-by forestkipuka. Amazingly, this species complex is found on the youngest of the Hawaiian Islands, with probably less than 0.5 m.y., which suggests rapid speciation processes. Field observations have led to the development of a hypothesis to match underground speciation with the dynamics of vegetational succession on the surface of active volcanoes. Planthopper range partitioning and geographic separation of populations by young lava flows, founder events and small population size may be important factors involved in rapid divergence.

Systematic analysis of rice (Oryza sativa) metabolic responses to herbivory.

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Alamgir, Kabir Md; Hojo, Yuko; Christeller, John T; Fukumoto, Kaori; Isshiki, Ryutaro; Shinya, Tomonori; Baldwin, Ian T; Galis, Ivan

2016-02-01

Plants defend against attack from herbivores by direct and indirect defence mechanisms mediated by the accumulation of phytoalexins and release of volatile signals, respectively. While the defensive arsenals of some plants, such as tobacco and Arabidopsis are well known, most of rice's (Oryza sativa) defence metabolites and their effectiveness against herbivores remain uncharacterized. Here, we used a non-biassed metabolomics approach to identify many novel herbivory-regulated metabolic signatures in rice. Most were up-regulated by herbivore attack while only a few were suppressed. Two of the most prominent up-regulated signatures were characterized as phenolamides (PAs), p-coumaroylputrescine and feruloylputrescine. PAs accumulated in response to attack by both chewing insects, i.e. feeding of the lawn armyworm (Spodoptera mauritia) and the rice skipper (Parnara guttata) larvae, and the attack of the sucking insect, the brown planthopper (Nilaparvata lugens, BPH). In bioassays, BPH insects feeding on 15% sugar solution containing p-coumaroylputrescine or feruloylputrescine, at concentrations similar to those elicited by heavy BPH attack in rice, had a higher mortality compared to those feeding on sugar diet alone. Our results highlight PAs as a rapidly expanding new group of plant defence metabolites that are elicited by herbivore attack, and deter herbivores in rice and other plants. © 2015 John Wiley & Sons Ltd.

Differences in Induced Volatile Emissions among Rice Varieties Result in Differential Attraction and Parasitism of Nilaparvata lugens Eggs by the Parasitoid Anagrus nilaparvatae in the Field

OpenAIRE

Lou , Yong-Gen; Hua, Xiaoyan; Turlings, Ted C. J.; Cheng, Jiaan; Chen, Xuexin; Ye, Gongyin

2007-01-01

We compared the volatiles of JA-treated plants of six rice varieties and then determined, in the laboratory and field, if they differed in attractiveness to Anagrus nilaparavate Pand et Wang, an egg parasitoid of rice planthoppers. Analyses of volatiles revealed significant differences among varieties, both in total quantity and quality of the blends emitted. On the basis of these differences, the six varieties could be roughly divided into three groups. In a Y-tube olfactometer, female wasps...

Driving Pest Insect Populations: Agricultural Chemicals Lead to an Adaptive Syndrome in Nilaparvata Lugens Stål (Hemiptera: Delphacidae).

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You, Lin-Lin; Wu, You; Xu, Bing; Ding, Jun; Ge, Lin-Quan; Yang, Guo-Qin; Song, Qi-Sheng; Stanley, David; Wu, Jin-Cai

2016-11-23

The brown planthopper (BPH) is a devastating pest of rice throughout Asia. In this paper we document the BPH biogeographic range expansion in China over the 20-year period, 1992 to 2012. We posed the hypothesis that the range expansion is due to a syndrome of adaptations to the continuous presence of agricultural chemicals (insecticides and a fungicide) over the last 40 years. With respect to biogeography, BPH ranges have expanded by 13% from 1992 to 1997 and by another 3% from 1997 to 2012. In our view, such expansions may follow primarily from the enhancing effects of JGM, among other agricultural chemicals, and from global warming. JGM treatments led to increased thermotolerance, recorded as decreased mortality under heat stress at 40 ± 1 °C (down from 80% to 55%) and increased fecundity (by 49%) at 34 °C. At the molecular level, JGM treatments led to increased abundances of mRNA encoding Acetyl Co-A carboxylase (Acc) (up 25%) and Hsp70 (up 32%) in experimental BPH. RNAi silencing of Hsp70 and Acc eliminated the JGM effects on fecundity and silencing Hsp70 reduced JGM-induced thermotolerance. Integrated with global climate change scenarios, such syndromes in pest insect species have potential for regional- and global-scale agricultural disasters.

Two new planthopper species (Hemiptera, Fulgoroidea, Caliscelidae) collected in pitfall traps in Zambia.

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Chmurova, Lucia; Webb, Michael D

2016-08-22

Two new species of planthoppers in the family Caliscelidae (Hemiptera: Fulgoroidea) are described from Zambia, i.e., Afronaso spinosa sp. n. and Calampocus zambiaensis sp. n. All specimens are flightless males and nearly all were collected from baited pitfall traps (except for one specimen collected from a yellow pan trap), suggesting that they live near to or on the ground.

Nitenpyram analogues with 1,4-dihydropyridine fixed cis-configuration:synthesis,insecticidal activities and molecular docking studies

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XUE Sijia

2013-08-01

Full Text Available A novel series of Nitenpyram analogues(Ia-Ij with 1,4-dihydropyridine fixed cis-configuration were designed and synthesized.Preliminary bioassays showed that most of them exhibited good insecticidal activities against Aphis medicagini and Brown rice planthopper at 500 mg/L and 100 mg/L.The analogue Ij afforded the best activity in vitro,that had 100% mortality at 4 mg/L against Brown rice planthopper and Aphis medicagin.In addition,the molecular docking simulations revealed that the structural uniqueness of these analogues may lead to a unique molecular recognition and binding mode,and the results explained the SARs observed in vitro, which shed light on the novel insecticidal mechanism of these novel nitenpyam analogues.

The improvement of rice varieties for major pest and diseases resistance

International Nuclear Information System (INIS)

Sahi, I.; Silitonga, T.S.

1988-01-01

Since 1971, the rice breeding program in Indonesia has developed on intensive program to improve varieties for yield potential, resistancy to major pests and diseases, early maturity good grain and eating quality. In recent years, the attacks of insects and diseases are very severe in rice cultivation in Asia. Much of the losses were due to acontinuous planting or certain varieties. Between 1966 and 1973 tungro occured in epidemic proportions on separate occasions in Indonesia, Thailand, Nort East India, Bangladesh, and Philippine. Since 1973, investation of brown planthopper and green leafhopper several damaged rice crop in most parts of Indonesia. Presently, rice improvement are directed to develop high yielding rice varieties that are resistant to brown planthopper, ragged stunt virus, blast, green leafhopper, and gallmidge. Screening for pests and diseases are conducted in the laboratory as well as in the field. The adoption of those improved varieties by farmers has contributed greatly in our efforts to attain self sufficiency in rice production in Indonesia. GH 147 -M-40 krad-Pn-89 (irradiated Barito) showed resistant to brown planthopper biotype 1 and 2 and moderately resistant to biotype 3. Napa 40 krad-St-12 has resistant reaction to blast. (authors). 4 refs, 8 tabs

Effects of seed mixture sowing with transgenic Bt rice and its parental line on the population dynamics of target stemborers and leafrollers, and non-target planthoppers.

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Li, Zhuo; Li, Li-Kun; Liu, Bin; Wang, Long; Parajulee, Megha N; Chen, Fa-Jun

2018-01-24

The widespread planting of insect-resistant crops has caused a dramatic shift in agricultural landscapes, thus raising concerns about the potential impacts on both target and non-target pests. In this study, we examined the potential effects of intra-specific seed mixture sowing with transgenic Bt rice (Bt) and its parental non-transgenic line (Nt) (100% Bt rice [Bt 100 ], 5% Nt+95% Bt [Nt 05 Bt 95 ], 10% Nt+90% Bt [Nt 10 Bt 90 ], 20% Nt+80% Bt [Nt 20 Bt 80 ], 40% Nt+60% Bt [Nt 40 Bt 60 ] and 100% Nt rice [Nt 100 ]) on target and non-target pests in a 2-year field trial in southern China. The occurrence of target pests, Sesamia inferens, Chilo suppressalis and Cnaphalocrocis medinalis, decreased with the increased ratio of Bt rice, and the mixture ratios with more than 90% Bt rice (Bt 100 and Nt 05 Bt 95 ) significantly increased the pest suppression efficiency, with the lowest occurrences of non-target planthoppers, Nilaparvata lugens and Sogatella furcifera in Nt 100 and Nt 05 Bt 95 . Furthermore, there were no significant differences in 1000-grain dry weight and grain dry weight per 100 plants between Bt 100 and Nt 05 Bt 95 . Seed mixture sowing of Bt rice with ≤10% (especially 5%) of its parent line was sufficient to overcome potential compliance issues that exist with the use of block or structured refuge to provide most effective control of both target and non-target pests without compromising the grain yield. It is also expected that the strategy of seed mixture sowing with transgenic Bt rice and the non-transgenic parental line would provide rice yield stability while decreasing the insecticide use frequency in rice production. © 2018 Institute of Zoology, Chinese Academy of Sciences.

Cis-12-oxo-phytodienoic acid stimulates rice defense response to a piercing-sucking insect.

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Guo, Hui-Min; Li, Hai-Chao; Zhou, Shi-Rong; Xue, Hong-Wei; Miao, Xue-Xia

2014-11-01

The brown planthopper (BPH, Nilaparvata lugens) is a destructive, monophagous, piercing-sucking insect pest of rice. Previous studies indicated that jasmonic acid (JA) positively regulates rice defense against chewing insect pests but negatively regulates it against the piercing-sucking insect of BPH. We here demonstrated that overexpression of allene oxide cyclase (AOC) but not OPR3 (cis-12-oxo-phytodienoic acid (OPDA) reductase 3, an enzyme adjacent to AOC in the JA synthetic pathway) significantly increased rice resistance to BPH, mainly by reducing the feeding activity and survival rate. Further analysis revealed that plant response to BPH under AOC overexpression was independent of the JA pathway and that significantly higher OPDA levels stimulated rice resistance to BPH. Microarray analysis identified multiple candidate resistance-related genes under AOC overexpression. OPDA treatment stimulated the resistance of radish seedlings to green peach aphid Myzus persicae, another piercing-sucking insect. These results imply that rice resistance to chewing insects and to sucking insects can be enhanced simultaneously through AOC-mediated increases of JA and OPDA and provide direct evidence of the potential application of OPDA in stimulating plant defense responses to piercing-sucking insect pests in agriculture. © The Author 2014. Published by the Molecular Plant Shanghai Editorial Office in association with Oxford University Press on behalf of CSPB and IPPE, SIBS, CAS.

Herbivore-induced callose deposition on the sieve plates of rice: an important mechanism for host resistance.

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Hao, Peiying; Liu, Caixiang; Wang, Yuanyuan; Chen, Rongzhi; Tang, Ming; Du, Bo; Zhu, Lili; He, Guangcun

2008-04-01

The brown planthopper (Nilaparvata lugens Stål; BPH) is a specialist herbivore on rice (Oryza sativa) that ingests phloem sap from the plant through its stylet mouthparts. Electronic penetration graphs revealed that BPH insects spent more time wandering over plants carrying the resistance genes Bph14 and Bph15, but less time ingesting phloem than they did on susceptible plants. They also showed that their feeding was frequently interrupted. Tests with [(14)C]sucrose showed that insects ingested much less phloem sap from the resistant than the susceptible plants. BPH feeding up-regulated callose synthase genes and induced callose deposition in the sieve tubes at the point where the stylet was inserted. The compact callose remained intact in the resistant plants, but genes encoding beta-1,3-glucanases were activated, causing unplugging of the sieve tube occlusions in susceptible plants. Continuing ingestion led to a remarkable reduction in the susceptible plants' sucrose content and activation of the RAmy3D gene, leading to starch hydrolysis and ultimately carbohydrate deprivation in the plants. Our results demonstrate that BPH feeding induces the deposition of callose on sieve plates in rice and that this is an important defense mechanism that prevents insects from ingesting phloem sap. In response, however, the BPH can unplug sieve tube occlusions by activating beta-1,3-glucanase genes in rice plants.

Relative Fitness and Feeding Capacity of Imidacloprid Resistant Nilaparvata lugens

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Jesayas A. Londingkene

2016-07-01

Full Text Available Imidacloprid is a neonicotinoid insecticide that is recommended for controlling Nilaparvata lugens. In Asian countries, such as, China, Vietnam, India, and Thailand, imidacloprid has caused resistance to N. lugens. Imidacloprid has also caused resistance to N. lugens based on some previous studies in Indonesia. The aim of this study was to determine the fitness and feeding capacity of imidacloprid-resistant N. lugens. The population of N. lugens used in this study had a resistance level of 50.64 times compared to the susceptible population. When the resistant and susceptible population of N. lugens did not receive any exposure to imidacloprid, the susceptible population had better fitness than the resistance one. However, the fitness of the resistant population increased when this population was resistance which sublethal cencentration (LC50 & LC20 of imidacloprid. The increase fitness of this resistant population most likely related to the increase in feeding capacity of the resistant population when they were treated which sublethal imidacloprid. These findings suggest that the field population of N. lugens that have developed resistance would increase the probability of outbreak if they were sprayed with imidacloprid.   INTISARI   Imidakloprid adalah insektisida neonicotinoid yang direkomendasikan untuk mengendalikan Nilaparvata lugens. Di negara Asia, seperti, China, Vietnam, India, dan Thailand, imidakloprid telah menyebabkan resistensi terhadap N. lugens. Di Indonesia, berdasarkan beberapa penelitian sebelumnya dilaporkan imidakloprid juga menyebabkan resistensi terhadap N. lugens. Tujuan penelitian ini untuk mengetahui kebugaran relatif dan kemampuan makan N. lugens resisten terhadap imidakloprid. Populasi N. lugens yang digunakan dalam penelitian ini mempunyai tingkat resistensi 50,64 kali dibandingkan dengan populasi peka. N. lugens populasi resisten dan peka apabila tidak dipapar dengan imidakloprid, populasi peka mempunyai kebugaran

An adenylyl cyclase gene (NlAC9) influences growth and fecundity in the brown planthopper, Nilaparvata lugens (Stål) (Hemiptera: Delphacidae)

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The cAMP/PKA intracellular signaling pathway is launched by adenylyl cyclase (AC) conversion of adenosine triphosphate (ATP) to 3', 5'-cyclic AMP (cAMP) and cAMP-dependent activation of PKA. Although this pathway is very well known in insect physiology, there is little to no information on it in som...

Collection of pure phloem sap from wheat and its chemical composition

International Nuclear Information System (INIS)

Hayashi, H.; Chino, M.

1986-01-01

Wheat Phloem sap was collected without contamination from the stylets of small brown planthopper severed by a YAG laser beam. The sugar, amino acid and inorganic ion composition was determined using only one μl of the sap. The sap had a high sucrose level (251 mM), and also a high K+ level (299 mM). Total amino acid compounds in the sap reached 262 mM. The dominant amino acids were glutamic acid, aspartic acid and serine, while r-amino butylic acid was absent. The major anion in the sap was Cl− and its concentration was 25.1 mM. Nitrate was also present at a concentration of 8.1 mM. These results suggested that the sap obtained from the cut end of the stylets of the small brown planthopper was a phloem origin of wheat. (author)

Spider (Araneae) predations on white-backed planthopper Sogatella furcifera in subtropical rice ecosystems, China.

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Wang, Xue-Qin; Wang, Guang-Hua; Zhu, Zeng-Rong; Tang, Qi-Yi; Hu, Yang; Qiao, Fei; Heong, Kong Luen; Cheng, Jia-An

2017-06-01

Spiders are effective biological control agents in rice ecosystems, but the comparative study of predations among main spider species under field conditions has not been fully explored owing to a lack of practical methodology. In this study, more than 6000 spiders of dominant species were collected from subtropical rice ecosystems to compare their predations on Sogatella furcifera (Horváth) (white-backed planthopper, WBPH) using DNA-based gut content analysis. The positive rates for all spider taxa were closely related to prey densities, as well as their behaviors and niches. The relationships of positive rates to prey planthopper densities for Pardosa pseudoannulata (Böes. et Str.), Coleosoma octomaculata (Böes. et Str.), Tetragnatha maxillosa Thorell and Ummeliata insecticeps (Böes. et Str.) under field conditions could be described using saturated response curves. Quantitative comparisons of predations among the four spider species confirmed that P. pseudoannulata and C. octomaculata were more rapacious than U. insecticeps and T. maxillosa under field conditions. A comparison of ratio of spiders to WBPH and positive rates between fields revealed that biological control by spiders could be effectively integrated with variety resistance. Generalist spiders could follow up WBPH population timely, and assemblages of spiders coupled with variety resistance could effectively suppress WBPH population. © 2016 Society of Chemical Industry. © 2016 Society of Chemical Industry.

Effect of Nitrogen Fertilizer on Herbivores and Its Stimulation to Major Insect Pests in Rice

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Zhong-xian LU

2007-03-01

Full Text Available Nitrogen is one of the most important factors in development of herbivore populations. The application of nitrogen fertilizer in plants can normally increase herbivore feeding preference, food consumption, survival, growth, reproduction, and population density, except few examples that nitrogen fertilizer reduces the herbivore performances. In most of the rice growing areas in Asia, the great increases in populations of major insect pests of rice, including planthoppers (Nilaparvata lugens and Sogatella furcifera, leaffolder (Cnaphalocrocis medinalis, and stem borers (Scirpophaga incertulas, Chilo suppressalis, S. innotata, C. polychrysus and Sesamia inferens were closely related to the long-term excessive application of nitrogen fertilizers. The optimal regime of nitrogen fertilizer in irrigated paddy fields is proposed to improve the fertilizer-nitrogen use efficiency and reduce the environmental pollution.

An EAR-motif-containing ERF transcription factor affects herbivore-induced signaling, defense and resistance in rice.

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Lu, Jing; Ju, Hongping; Zhou, Guoxin; Zhu, Chuanshu; Erb, Matthias; Wang, Xiaopeng; Wang, Peng; Lou, Yonggen

2011-11-01

Ethylene responsive factors (ERFs) are a large family of plant-specific transcription factors that are involved in the regulation of plant development and stress responses. However, little to nothing is known about their role in herbivore-induced defense. We discovered a nucleus-localized ERF gene in rice (Oryza sativa), OsERF3, that was rapidly up-regulated in response to feeding by the rice striped stem borer (SSB) Chilo suppressalis. Antisense and over-expression of OsERF3 revealed that it positively affects transcript levels of two mitogen-activated protein kinases (MAPKs) and two WRKY genes as well as concentrations of jasmonate (JA), salicylate (SA) and the activity of trypsin protease inhibitors (TrypPIs). OsERF3 was also found to mediate the resistance of rice to SSB. On the other hand, OsERF3 was slightly suppressed by the rice brown planthopper (BPH) Nilaparvata lugens (Stål) and increased susceptibility to this piercing sucking insect, possibly by suppressing H(2)O(2) biosynthesis. We propose that OsERF3 affects early components of herbivore-induced defense responses by suppressing MAPK repressors and modulating JA, SA, ethylene and H(2)O(2) pathways as well as plant resistance. Our results also illustrate that OsERF3 acts as a central switch that gears the plant's metabolism towards an appropriate response to chewing or piercing/sucking insects. © 2011 The Authors. The Plant Journal © 2011 Blackwell Publishing Ltd.

Jasmonic acid carboxyl methyltransferase regulates development and herbivory-induced defense response in rice.

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Qi, Jinfeng; Li, Jiancai; Han, Xiu; Li, Ran; Wu, Jianqiang; Yu, Haixin; Hu, Lingfei; Xiao, Yutao; Lu, Jing; Lou, Yonggen

2016-06-01

Jasmonic acid (JA) and related metabolites play a key role in plant defense and growth. JA carboxyl methyltransferase (JMT) may be involved in plant defense and development by methylating JA to methyl jasmonate (MeJA) and thus influencing the concentrations of JA and related metabolites. However, no JMT gene has been well characterized in monocotyledon defense and development at the molecular level. After we cloned a rice JMT gene, OsJMT1, whose encoding protein was localized in the cytosol, we found that the recombinant OsJMT1 protein catalyzed JA to MeJA. OsJMT1 is up-regulated in response to infestation with the brown planthopper (BPH; Nilaparvata lugens). Plants in which OsJMT1 had been overexpressed (oe-JMT plants) showed reduced height and yield. These oe-JMT plants also exhibited increased MeJA levels but reduced levels of herbivore-induced JA and jasmonoyl-isoleucine (JA-Ile). The oe-JMT plants were more attractive to BPH female adults but showed increased resistance to BPH nymphs, probably owing to the different responses of BPH female adults and nymphs to the changes in levels of H2 O2 and MeJA in oe-JMT plants. These results indicate that OsJMT1, by altering levels of JA and related metabolites, plays a role in regulating plant development and herbivore-induced defense responses in rice. © 2015 Institute of Botany, Chinese Academy of Sciences.

Contrasting effects of ethylene biosynthesis on induced plant resistance against a chewing and a piercing-sucking herbivore in rice.

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Lu, Jing; Li, Jiancai; Ju, Hongping; Liu, Xiaoli; Erb, Matthias; Wang, Xia; Lou, Yonggen

2014-11-01

Ethylene is a stress hormone with contrasting effects on herbivore resistance. However, it remains unknown whether these differences are plant- or herbivore-specific. We cloned a rice 1-aminocyclopropane-1-carboxylic acid (ACC) synthase gene, OsACS2, whose transcripts were rapidly up-regulated in response to mechanical wounding and infestation by two important pests: the striped stem borer (SSB) Chilo suppressalis and the brown planthopper (BPH) Nilaparvata lugens. Antisense expression of OsACS2 (as-acs) reduced elicited ethylene emission, SSB-elicited trypsin protease inhibitor (TrypPI) activity, SSB-induced volatile release, and SSB resistance. Exogenous application of ACC restored TrypPI activity and SSB resistance. In contrast to SSB, BPH infestation increased volatile emission in as-acs lines. Accordingly, BPH preferred to feed and oviposit on wild-type (WT) plants--an effect that could be attributed to two repellent volatiles, 2-heptanone and 2-heptanol, that were emitted in higher amounts by as-acs plants. BPH honeydew excretion was reduced and natural enemy attraction was enhanced in as-acs lines, resulting in higher overall resistance to BPH. These results demonstrate that ethylene signaling has contrasting, herbivore-specific effects on rice defense responses and resistance against a chewing and a piercing-sucking insect, and may mediate resistance trade-offs between herbivores of different feeding guilds in rice. © The Author 2014. Published by the Molecular Plant Shanghai Editorial Office in association with Oxford University Press on behalf of CSPB and IPPE, SIBS, CAS.

[Effects of azadirachtin on rice plant volatiles induced by Nilaparvata lugens].

Science.gov (United States)

Lu, Hai-Yan; Liu, Fang; Zhu, Shu-De; Zhang, Qing

2010-01-01

With the method of solid phase microextraction (SPME), a total of twenty-five volatiles were collected from rice plants induced by Nilaparvata lugens, and after applying azadirachtin fourteen of them were qualitatively identified by gas chromatography coupled by mass spectrometry (GC-MS), mainly of nine kinds of sesquiterpenes. Comparing with healthy rice plants, the plants attacked by N. lugens had more kinds of volatiles, including limonene, linalool, methyl salicylate, unknown 6, unknown 7, zingiberene, nerolidol, and hexadecane. Applying azadirachtin did not result in the production of new kind volatiles, but affected the relative concentrations of the volatiles induced by N. lugens. The proportions of limonene, linalool, methyl salicylate, unknown 6, zingiberene, and hexadecane changed obviously with the concentration of applied azadirachtin, while those of methyl salicylate, unknown 6, unknown 7, zingiberene, and nerolidol changed significantly with the days after azadirachtin application. Azadirachtin concentration, rice variety, and N. lugens density had significant interactions on the relative concentrations of all test N. lugens-induced volatiles.

Possible Source Populations of the White-backed Planthopper in the Greater Mekong Subregion Revealed by Mitochondrial DNA Analysis

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Li, Xiang-Yong; Chu, Dong; Yin, Yan-Qiong; Zhao, Xue-Qing; Chen, Ai-Dong; Khay, Sathya; Douangboupha, Bounneuang; Kyaw, Mu Mu; Kongchuensin, Manita; Ngo, Vien Vinh; Nguyen, Chung Huy

2016-12-01

The white-backed planthopper, Sogatella furcifera (Horváth) (Hemiptera: Delphacidae), is a serious pest of rice in Asia. However, little is known regarding the migration of this pest insect from the Greater Mekong Subregion (GMS) including Cambodia, Laos, Myanmar (Burma), Thailand, and Vietnam, into China’s Yunnan Province. To determine the migration patterns of S. furcifera in the GMS and putative secondary immigration inside China’s Yunnan Province, we investigated the population genetic diversity, genetic structure, and gene flow of 42 S. furcifera populations across the six countries in the GMS by intensive sampling using mitochondrial genes. Our study revealed the potential emigration of S. furcifera from the GMS consists primarily of three major sources: 1) the S. furcifera from Laos and Vietnam migrate into south and southeast Yunnan, where they proceed to further migrate into northeast and central Yunnan; 2) the S. furcifera from Myanmar migrate into west Yunnan, and/or central Yunnan, and/or northeast Yunnan; 3) the S. furcifera from Cambodia migrate into southwest Yunnan, where the populations can migrate further into central Yunnan. The new data will not only be helpful in predicting population dynamics of the planthopper, but will also aid in regional control programs for this economically important pest insect.

GEODATA: Information System Based on Geospatial for Early Warning Tracking and Analysis Agricultural Plant Diseases in Central Java

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Prasetyo, S. Y. J.; Agus, Y. H.; Dewi, C.; Simanjuntak, B. H.; Hartomo, K. D.

2017-03-01

The Government of Indonesia is currently faced with the problems of food, especially rice. It needs in large numbers that have to import from neighboring countries. Actually, the Indonesian government has the ability to produce rice to meet national needs but is still faced with the problem of pest attack rice annually increasing extent. One of the factors is that geographically Indonesia located on the migration path of world rice insect pests (called BPH or Brown Planthoppers) (Nilaparvata lugens Stal.) It leads endemic status annually. One proposed strategy to be applied is to use an early warning system based on a specific region of the main pest population. The proposed information system called GEODATA. GEODATA is Geospatial Outbreak of Disease Tracking and Analysis. The system works using a library ESSA (Exponential Smoothing - Spatial Autocorrelation) developed in previous studies in Satya Wacana Christian University. GEODATA built to meet the qualifications required surveillance device by BMKG (Indonesian Agency of Meteorology, Climatology and Geophysics’ Central Java Provinces), BPTPH (Indonesian Agency of Plant Protection and Horticulture) Central Java Provinces, BKP-KP District Boyolali, Central Java, (Indonesian Agency of Food Security and Agriculture Field Supervisor, District Boyolali, Central Java Provinces) and farmer groups. GIS GEODATA meets the needs of surveillance devices that include: (1) mapping of the disease, (2) analysis of the dynamics of the disease, and (3) prediction of attacks / disease outbreaks in a particular region. GIS GEODATA is currently under implementation in the laboratory field observations of plant pest in Central Java province, Indonesia.

Brown Fat and Browning for the Treatment of Obesity and Related Metabolic Disorders

Directory of Open Access Journals (Sweden)

So Hun Kim

2016-01-01

Full Text Available Brown fat is a specialized fat depot that can increase energy expenditure and produce heat. After the recent discovery of the presence of active brown fat in human adults and novel transcription factors controlling brown adipocyte differentiation, the field of the study of brown fat has gained great interest and is rapidly growing. Brown fat expansion and/or activation results in increased energy expenditure and a negative energy balance in mice and limits weight gain. Brown fat is also able to utilize blood glucose and lipid and results in improved glucose metabolism and blood lipid independent of weight loss. Prolonged cold exposure and beta adrenergic agonists can induce browning of white adipose tissue. The inducible brown adipocyte, beige adipocyte evolving by thermogenic activation of white adipose tissue have different origin and molecular signature from classical brown adipocytes but share the characteristics of high mitochondria content, UCP1 expression and thermogenic capacity when activated. Increasing browning may also be an efficient way to increase whole brown fat activity. Recent human studies have shown possibilities that findings in mice can be reproduced in human, making brown fat a good candidate organ to treat obesity and its related disorders.

Toxicity of Insecticides Targeting Rice Planthoppers to Adult and Immature Stages of Trichogramma chilonis (Hymenoptera: Trichogrammatidae).

Science.gov (United States)

Ko, Ko; Liu, Yudi; Hou, Maolin; Babendreier, Dirk; Zhang, Feng; Song, Kai

2015-02-01

Planthopper-targeting insecticides, pymetrozine, thiamethoxam, buprofezin, and nitenpyram, were tested under laboratory conditions for toxicity to adults and immatures of Trichogramma chilonis Ishii, using standard tests described by International Organization for Biological Control (IOBC). In the dry film residue test, all insecticides resulted in >90% mortality in T. chilonis adults and were ranked as moderately harmful. Persistent toxicity tests revealed that nitenpyram was short-lived and the other three insecticides were of slightly persistent toxicity to the wasp adults. Effects of the insecticides on egg, larval, and prepupal stages of T. chilonis were investigated with striped stem borer as host. At the three stages of T. chilonis (within the host egg), all the insecticides reduced parasitism rate, but nitenpyram and pymetrozine applied at egg stage, buprofezin and nitenpyram at larval stage, and buprofezin and thiamethoxam at prepupal stage of T. chilonis reduced parasitism by buprofezin at prepupal stage resulted in >30% reduction in emergence rate as compared with the control and were categorized as harmful. Immature duration of T. chilonis was only significantly extended by nitenpyram applied to egg stage than the control. Sex ratio of emerged wasps was not affected by the treatment to immature stages. The data are of significance for IPM programs incorporating inundative release of T. chilonis for control of lepidopteran rice pests where there is heavy co-occurrence of planthoppers. © The Authors 2015. Published by Oxford University Press on behalf of Entomological Society of America. All rights reserved. For Permissions, please email: journals.permissions@oup.com.

[Human brown adipose tissue].

Science.gov (United States)

Virtanen, Kirsi A; Nuutila, Pirjo

2015-01-01

Adult humans have heat-producing and energy-consuming brown adipose tissue in the clavicular region of the neck. There are two types of brown adipose cells, the so-called classic and beige adipose cells. Brown adipose cells produce heat by means of uncoupler protein 1 (UCP1) from fatty acids and sugar. By applying positron emission tomography (PET) measuring the utilization of sugar, the metabolism of brown fat has been shown to multiply in the cold, presumably influencing energy consumption. Active brown fat is most likely present in young adults, persons of normal weight and women, least likely in obese persons.

Selection of nectar plants for use in ecological engineering to promote biological control of rice pests by the predatory bug, Cyrtorhinus lividipennis, (Heteroptera: Miridae).

Science.gov (United States)

Zhu, Pingyang; Lu, Zhongxian; Heong, Kongluen; Chen, Guihua; Zheng, Xusong; Xu, Hongxing; Yang, Yajun; Nicol, Helen I; Gurr, Geoff M

2014-01-01

Ecological engineering for pest management involves the identification of optimal forms of botanical diversity to incorporate into a farming system to suppress pests, by promoting their natural enemies. Whilst this approach has been extensively researched in many temperate crop systems, much less has been done for rice. This paper reports the influence of various plant species on the performance of a key natural enemy of rice planthopper pests, the predatory mirid bug, Cyrtorhinus lividipennis. Survival of adult males and females was increased by the presence of flowering Tagetes erecta, Trida procumbens, Emilia sonchifolia (Compositae), and Sesamum indicum (Pedaliaceae) compared with water or nil controls. All flower treatments resulted in increased consumption of brown plant hopper, Nilaparvata lugens, and for female C. lividipennis, S. indicum was the most favorable. A separate study with a wider range of plant species and varying densities of prey eggs showed that S. indicum most strongly promoted predation by C. lividipennis. Reflecting this, S. indicum gave a relatively high rate of prey search and low prey handling time. On this basis, S. indicum was selected for more detailed studies to check if its potential incorporation into the farming system would not inadvertently benefit Cnaphalocrocis medinalis and Marasmia patnalis, serious Lepidoptera pests of rice. Adult longevity and fecundity of both pests was comparable for S. indicum and water treatments and significantly lower than the honey solution treatment. Findings indicate that S. indicumis well suited for use as an ecological engineering plant in the margins of rice crops. Sesame indicum can be a valuable crop as well as providing benefits to C. lividipennis whilst denying benefit to key pests.

Selection of nectar plants for use in ecological engineering to promote biological control of rice pests by the predatory bug, Cyrtorhinus lividipennis, (Heteroptera: Miridae.

Directory of Open Access Journals (Sweden)

Pingyang Zhu

Full Text Available Ecological engineering for pest management involves the identification of optimal forms of botanical diversity to incorporate into a farming system to suppress pests, by promoting their natural enemies. Whilst this approach has been extensively researched in many temperate crop systems, much less has been done for rice. This paper reports the influence of various plant species on the performance of a key natural enemy of rice planthopper pests, the predatory mirid bug, Cyrtorhinus lividipennis. Survival of adult males and females was increased by the presence of flowering Tagetes erecta, Trida procumbens, Emilia sonchifolia (Compositae, and Sesamum indicum (Pedaliaceae compared with water or nil controls. All flower treatments resulted in increased consumption of brown plant hopper, Nilaparvata lugens, and for female C. lividipennis, S. indicum was the most favorable. A separate study with a wider range of plant species and varying densities of prey eggs showed that S. indicum most strongly promoted predation by C. lividipennis. Reflecting this, S. indicum gave a relatively high rate of prey search and low prey handling time. On this basis, S. indicum was selected for more detailed studies to check if its potential incorporation into the farming system would not inadvertently benefit Cnaphalocrocis medinalis and Marasmia patnalis, serious Lepidoptera pests of rice. Adult longevity and fecundity of both pests was comparable for S. indicum and water treatments and significantly lower than the honey solution treatment. Findings indicate that S. indicumis well suited for use as an ecological engineering plant in the margins of rice crops. Sesame indicum can be a valuable crop as well as providing benefits to C. lividipennis whilst denying benefit to key pests.

OsMPK3 positively regulates the JA signaling pathway and plant resistance to a chewing herbivore in rice.

Science.gov (United States)

Wang, Qi; Li, Jiancai; Hu, Lingfei; Zhang, Tongfang; Zhang, Guren; Lou, Yonggen

2013-07-01

KEY MESSAGE : Silencing OsMPK3 decreased elicited JA levels, which subsequently reduced levels of herbivore-induced trypsin protease inhibitors (TrypPIs) and improved the performance of SSB larvae, but did not influence BPH. Mitogen-activated protein kinases (MPKs) are known to play an important role in plant defense by transferring biotic and abiotic signals into programmed cellular responses. However, their functions in the herbivore-induced defense response in rice remain largely unknown. Here, we identified a MPK3 gene from rice, OsMPK3, and found that its expression levels were up-regulated in response to infestation by the larvae of the striped stem borer (SSB) (Chilo suppressalis), to mechanical wounding and to treatment with jasmonic acid (JA), but not to infestation by the brown planthopper (BPH) Nilaparvata lugens or to treatment with salicylic acid. Moreover, mechanical wounding and SSB infestation induced the expression of OsMPK3 strongly and quickly, whereas JA treatment induced the gene more weakly and slowly. Silencing OsMPK3 (ir-mpk3) reduced the expression of the gene by 50-70 %, decreased elicited levels of JA and diminished the expression of a lipoxygenase gene OsHI-LOX and an allene oxide synthase gene OsAOS1. The reduced JA signaling in ir-mpk3 plants decreased the levels of herbivore-induced trypsin protease inhibitors (TrypPIs) and improved the performance of SSB larvae, but did not influence BPH. Our findings suggest that the gene OsMPK3 responds early in herbivore-induced defense and can be regulated by rice plants to activate a specific and appropriate defense response to different herbivores.

Brown adipocyte function

DEFF Research Database (Denmark)

Winther, Sally

. The first part of this thesis explores this by identifying and investigating two novel kinase regulators of brown adipocyte function. Study 1 demonstrates that spleen tyrosine kinase is a hitherto undescribed regulator of brown adipocyte differentiation and activation. Study 2 identifies glycogen synthase...

Brown dwarfs as dark galactic halos

International Nuclear Information System (INIS)

Adams, F.C.; Walker, T.P.

1990-01-01

The possibility that the dark matter in galactic halos can consist of brown dwarf stars is considered. The radiative signature for such halos consisting solely of brown dwarfs is calculated, and the allowed range of brown dwarf masses, the initial mass function (IMF), the stellar properties, and the density distribution of the galactic halo are discussed. The prediction emission from the halo is compared with existing observations. It is found that, for any IMF of brown dwarfs below the deuterium burning limit, brown dwarf halos are consistent with observations. Brown dwarf halos cannot, however, explain the recently observed near-IR background. It is shown that future satellite missions will either detect brown dwarf halos or place tight constraints on the allowed range of the IMF. 30 refs

Benchmarking Brown Dwarf Models With a Non-irradiated Transiting Brown Dwarf in Praesepe

Science.gov (United States)

Beatty, Thomas; Marley, Mark; Line, Michael; Gizis, John

2018-05-01

We wish to use 9.4 hours of Spitzer time to observe two eclipses, one each at 3.6um and 4.5um, of the transiting brown dwarf AD 3116b. AD 3116b is a 54.2+/-4.3 MJ, 1.08+/-0.07 RJ object on a 1.98 day orbit about a 3200K M-dwarf. Uniquely, AD 3116 and its host star are both members of Praesepe, a 690+/-60 Myr old open cluster. AD 3116b is thus one of two transiting brown dwarfs for which we have a robust isochronal age that is not dependent upon brown dwarf evolutionary models, and the youngest brown dwarf for which this is the case. Importantly, the flux AD 3116b receives from its host star is only 0.7% of its predicted internal luminosity (Saumon & Marley 2008). This makes AD 3116b the first known transiting brown dwarf that simultaneously has a well-defined age, and that receives a negligible amount of external irradiation, and a unique laboratory to test radius and luminosity predictions from brown dwarf evolutionary models. Our goal is to measure the emission from the brown dwarf. AD 3116b should have large, 25 mmag, eclipse depths in the Spitzer bandpasses, and we expect to measure them with a precision of +/-0.50 mmag at 3.6um and +/-0.54 mmag at 4.5um. This will allow us to make measure AD 3116b?s internal effective temperature to +/-40K. We will also use the upcoming Gaia DR2 parallaxes to measure AD 3116b's absolute IRAC magnitudes and color, and hence determine the cloud properties of the atmosphere. As the only known brown dwarf with an independently measured mass, radius, and age, Spitzer measurements of AD 3116b's luminosity and clouds will provide a critical benchmark for brown dwarf observation and theory.

Genetic divergence is decoupled from ecological diversification in the Hawaiian Nesosydne planthoppers.

Science.gov (United States)

Roesch Goodman, Kari; Welter, Stephen C; Roderick, George K

2012-09-01

Adaptive radiation involves ecological shifts coupled with isolation of gene pools. However, we know little about what drives the initial stages of divergence. We study a system in which ecological diversification is found within a chronologically well-defined geological matrix to provide insight into this enigmatic phase of radiation. We tested the hypothesis that a period of geographic isolation precedes ecological specialization in an adaptive radiation of host-specialized Hawaiian planthoppers. We examined population structure and history using mitochondrial and multiple independent microsatellite loci in a species whose geographic distribution on the island of Hawaii enabled us to observe the chronology of divergence in its very earliest stages. We found that genetic divergence is associated with geographic features but not different plant hosts and that divergence times are very recent and on the same timescales as the dynamic geology of the island. Our results suggest an important role for geography in the dynamics of the early stages of divergence. © 2012 The Author(s). Evolution© 2012 The Society for the Study of Evolution.

European brown hare syndrome virus in free-ranging European brown hares from Argentina

DEFF Research Database (Denmark)

Frolich, K.; Kujawski, G.E.J.G.; Rudolph, M.

2003-01-01

From 1998 to 2000, serum samples of 80 shot European brown hares (Lepus europaeus) from Argentina were examined for antibodies against European brown hare syndrome virus (EBHSV) and 80 spleen samples were tested for EBHSV-antigen by enzyme linked immunosorbent assay (ELISA). Nine hares were posit...... in these hares. This is the first report of antibodies to EBHSV, EBHSV-antigen, and electron microscopy findings in free-ranging European brown hares from South America....

7 CFR 29.3505 - Brown colors.

Science.gov (United States)

2010-01-01

... 7 Agriculture 2 2010-01-01 2010-01-01 false Brown colors. 29.3505 Section 29.3505 Agriculture... Type 95) § 29.3505 Brown colors. A group of colors ranging from a light brown to a dark brown. These colors vary from medium to low saturation and from medium to very low brillance. As used in these...

7 CFR 29.2504 - Brown colors.

Science.gov (United States)

2010-01-01

... 7 Agriculture 2 2010-01-01 2010-01-01 false Brown colors. 29.2504 Section 29.2504 Agriculture...-Cured Tobacco (u.s. Types 22, 23, and Foreign Type 96) § 29.2504 Brown colors. A group of colors ranging from a reddish brown to yellowish brown. These colors vary from low to medium saturation and from very...

Resistance of rice to insect pests mediated by suppression of serotonin biosynthesis.

Science.gov (United States)

Lu, Hai-Ping; Luo, Ting; Fu, Hao-Wei; Wang, Long; Tan, Yuan-Yuan; Huang, Jian-Zhong; Wang, Qing; Ye, Gong-Yin; Gatehouse, Angharad M R; Lou, Yong-Gen; Shu, Qing-Yao

2018-05-07

Rice is one of the world's most important foods, but its production suffers from insect pests, causing losses of billions of dollars, and extensive use of environmentally damaging pesticides for their control 1,2 . However, the molecular mechanisms of insect resistance remain elusive. Although a few resistance genes for planthopper have been cloned, no rice germplasm is resistant to stem borers. Here, we report that biosynthesis of serotonin, a neurotransmitter in mammals 3 , is induced by insect infestation in rice, and its suppression confers resistance to planthoppers and stem borers, the two most destructive pests of rice 2 . Serotonin and salicylic acid derive from chorismate 4 . In rice, the cytochrome P450 gene CYP71A1 encodes tryptamine 5-hydroxylase, which catalyses conversion of tryptamine to serotonin 5 . In susceptible wild-type rice, planthopper feeding induces biosynthesis of serotonin and salicylic acid, whereas in mutants with an inactivated CYP71A1 gene, no serotonin is produced, salicylic acid levels are higher and plants are more insect resistant. The addition of serotonin to the resistant rice mutant and other brown planthopper-resistant genotypes results in a loss of insect resistance. Similarly, serotonin supplementation in artificial diet enhances the performance of both insects. These insights demonstrate that regulation of serotonin biosynthesis plays an important role in defence, and may prove valuable for breeding insect-resistant cultivars of rice and other cereal crops.

Novel nuances of human brown fat

DEFF Research Database (Denmark)

Scheele, Camilla; Larsen, Therese Juhlin; Nielsen, Søren

2014-01-01

the types of thermogenic adipocytes in humans. We recently published a contradictory mRNA expression signature of human supraclavicular fat defined by an upregulation of the brite marker TBX1 along with the classical brown markers ZIC1 and LHX8, as well as genes indicating brown fat activity including UCP1......, there was no difference in UCP1, PGC-1α, PRDM16, suggesting both depots had equal brown fat potency. Taken together, supraclavicular brown fat derived from adult humans seems to represent a type of brown fat with distinct features from both subcutaneous white/brite and interscapular brown fat. Therefore......There is a current debate in the literature on whether human fat derived from the supraclavicular region should be classified as brown, or as the white fat-derived less potent, brite/beige. This commentary addresses whether the existing classification defined in mice is sufficient to describe...

Insect Analogue to the Lotus Leaf: A Planthopper Wing Membrane Incorporating a Low-Adhesion, Nonwetting, Superhydrophobic, Bactericidal, and Biocompatible Surface.

Science.gov (United States)

Watson, Gregory S; Green, David W; Cribb, Bronwen W; Brown, Christopher L; Meritt, Christopher R; Tobin, Mark J; Vongsvivut, Jitraporn; Sun, Mingxia; Liang, Ai-Ping; Watson, Jolanta A

2017-07-19

Nature has produced many intriguing and spectacular surfaces at the micro- and nanoscales. These small surface decorations act for a singular or, in most cases, a range of functions. The minute landscape found on the lotus leaf is one such example, displaying antiwetting behavior and low adhesion with foreign particulate matter. Indeed the lotus leaf has often been considered the "benchmark" for such properties. One could expect that there are animal counterparts of this self-drying and self-cleaning surface system. In this study, we show that the planthopper insect wing (Desudaba danae) exhibits a remarkable architectural similarity to the lotus leaf surface. Not only does the wing demonstrate a topographical likeness, but some surface properties are also expressed, such as nonwetting behavior and low adhering forces with contaminants. In addition, the insect-wing cuticle exhibits an antibacterial property in which Gram-negative bacteria (Porphyromonas gingivalis) are killed over many consecutive waves of attacks over 7 days. In contrast, eukaryote cell associations, upon contact with the insect membrane, lead to a formation of integrated cell sheets (e.g., among human stem cells (SHED-MSC) and human dermal fibroblasts (HDF)). The multifunctional features of the insect membrane provide a potential natural template for man-made applications in which specific control of liquid, solid, and biological contacts is desired and required. Moreover, the planthopper wing cuticle provides a "new" natural surface with which numerous interfacial properties can be explored for a range of comparative studies with both natural and man-made materials.

The insect ecdysone receptor is a good potential target for RNAi-based pest control.

Science.gov (United States)

Yu, Rong; Xu, Xinping; Liang, Yongkang; Tian, Honggang; Pan, Zhanqing; Jin, Shouheng; Wang, Na; Zhang, Wenqing

2014-01-01

RNA interference (RNAi) has great potential for use in insect pest control. However, some significant challenges must be overcome before RNAi-based pest control can become a reality. One challenge is the proper selection of a good target gene for RNAi. Here, we report that the insect ecdysone receptor (EcR) is a good potential target for RNAi-based pest control in the brown planthopper Nilaparvata lugens, a serious insect pest of rice plants. We demonstrated that the use of a 360 bp fragment (NlEcR-c) that is common between NlEcR-A and NlEcR-B for feeding RNAi experiments significantly decreased the relative mRNA expression levels of NlEcR compared with those in the dsGFP control. Feeding RNAi also resulted in a significant reduction in the number of offspring per pair of N. lugens. Consequently, a transgenic rice line expressing NlEcR dsRNA was constructed by Agrobacterium- mediated transformation. The results of qRT-PCR showed that the total copy number of the target gene in all transgenic rice lines was 2. Northern blot analysis showed that the small RNA of the hairpin dsNlEcR-c was successfully expressed in the transgenic rice lines. After newly hatched nymphs of N. lugens fed on the transgenic rice lines, effective RNAi was observed. The NlEcR expression levels in all lines examined were decreased significantly compared with the control. In all lines, the survival rate of the nymphs was nearly 90%, and the average number of offspring per pair in the treated groups was significantly less than that observed in the control, with a decrease of 44.18-66.27%. These findings support an RNAi-based pest control strategy and are also important for the management of rice insect pests.

The 9-lipoxygenase Osr9-LOX1 interacts with the 13-lipoxygenase-mediated pathway to regulate resistance to chewing and piercing-sucking herbivores in rice.

Science.gov (United States)

Zhou, Guoxin; Ren, Nan; Qi, Jingfeng; Lu, Jing; Xiang, Caiyu; Ju, Hongping; Cheng, Jiaan; Lou, Yonggen

2014-09-01

Oxylipins produced by the 13-lipoxygenase (LOX) have been reported to play an important role in plant defense responses to herbivores. Yet, the role of oxylipins produced by the 9-LOX pathway in this process remains largely unknown. Here we cloned a gene encoding a chloroplast-localized 9-LOX, Osr9-LOX1, from rice. Transcriptional analysis revealed that herbivore infestation, mechanical wounding and jasmonic acid (JA) treatment either repressed or did not enhance the level of Osr9-LOX1 transcripts at early stages but did at later stages, whereas salicylic acid (SA) treatment quickly increased the transcript level of Osr9-LOX1. Antisense expression of Osr9-lox1 (as-r9lox1) decreased the amount of wound-induced (Z)-3-hexenal but increased levels of striped stem borer (SSB)-induced linolenic acid, JA, SA and trypsin protease inhibitors. These changes were associated with increased resistance in rice to the larvae of the SSB Chilo suppressalis. In contrast, although no significant differences were observed in the duration of the nymph stage or the number of eggs laid by female adults between the brown planthopper (BPH) Nilaparvata lugens that fed on as-r9lox1 lines and BPH that fed on wild-type (WT) rice plants, the survival rate of BPH nymphs that fed on as-r9lox1 lines was higher than that of nymphs that fed on WT plants, possibly because of a higher JA level. The results demonstrate that Osr9-LOX1 plays an important role in regulating an herbivore-induced JA burst and cross-talk between JA and SA, and in controlling resistance in rice to chewing and phloem-feeding herbivores. © 2014 Scandinavian Plant Physiology Society.

Fucoidans from brown seaweeds

DEFF Research Database (Denmark)

Ale, Marcel Tutor; Meyer, Anne S.

2013-01-01

-proliferative effects on cancer cells. Recent work has revealed distinct structural features of fucoidans obtained from different brown seaweed sources. Fucoidans are classically obtained from brown seaweeds by multi-step, hot acid extraction, but the structural and compositional traits, and possibly the bioactivity......Fucoidan or fucoidans cover a family of sulfated fucose-rich polysaccharides, built of a backbone of L-fucose units, and characteristically found in brown seaweeds. Fucoidans have potential therapeutic properties, including anti-inflammatory and anti-coagulant activities, as well as anti...

Understanding Brown Dwarf Variability

Science.gov (United States)

Marley, Mark S.

2013-01-01

Surveys of brown dwarf variability continue to find that roughly half of all brown dwarfs are variable. While variability is observed amongst all types of brown dwarfs, amplitudes are typically greatest for L-T transition objects. In my talk I will discuss the possible physical mechanisms that are responsible for the observed variability. I will particularly focus on comparing and contrasting the effects of changes in atmospheric thermal profile and cloud opacity. The two different mechanisms will produce different variability signatures and I will discuss the extent to which the current datasets constrain both mechanisms. By combining constraints from studies of variability with existing spectral and photometric datasets we can begin to construct and test self-consistent models of brown dwarf atmospheres. These models not only aid in the interpretation of existing objects but also inform studies of directly imaged giant planets.

Influence of environment and climate on occurrence of the cixiid planthopper Hyalesthes obsoletus, the vector of the grapevine disease 'bois noir'.

Science.gov (United States)

Panassiti, Bernd; Breuer, Michael; Marquardt, Stacey; Biedermann, Robert

2013-12-01

Species distribution models (SDMs), which are well established in many fields of biological research, are still uncommon in the agricultural risk analysis of pest insects. To exemplify the use of SDMs, we investigated the influence of environmental factors on the occurrence of Hyalesthes obsoletus Signoret (Hemiptera: Cixiidae). The planthopper is the only known vector of the grapevine yellows disease 'bois noir'. The study was conducted in 145 locations in the Baden region of southwest Germany. The planthopper was surveyed on host plant patches, consisting of stinging nettle and/or bindweeds. We used a stratified modelling framework where (1) species presence-absence data were related to an extensive environmental dataset using logistic regressions; and (2) different types of average models were developed based on an information theoretic method. The results show that the incidence of H. obsoletus is associated to above- as well as below-ground environmental factors, particularly to the amount of fine soil and average annual precipitation. This result was consistent across all average models. The relative importance of other environmental variables was dependent upon the average model under consideration and thus may vary according to their intended use, either the explanation of habitat requirements or the prediction and mapping of occurrence risks. The study showed that SDMs offer a quantification of species' habitat requirements and thus, could represent a valuable tool for pest management purposes. By providing examples of current issues of grapevine pests in viticulture, we discuss the use of SDMs in agricultural risk analysis and highlight their advantages and caveats.

Resistance monitoring and cross-resistance role of CYP6CW1 between buprofezin and pymetrozine in field populations of Laodelphax striatellus (Fallén)

OpenAIRE

Zhang, Yueliang; Han, Yangchun; Liu, Baosheng; Yang, Qiong; Guo, Huifang; Liu, Zewen; Wang, Lihua; Fang, Jichao

2017-01-01

Monitoring resistance and investigating insecticide resistance mechanisms are necessary for controlling the small brown planthopper, Laodelphax striatellus. The susceptibility to four common insecticides of L. striatellus collected from Jiangsu, Anhui, Zhejiang and Jilin provinces of China in 2015 was monitored. The results showed that all field populations remained susceptible to chlorpyrifos and thiamethoxam with resistance ratios (RRs) of 2.3- to 9.5 and 1.6- to 3.3, respectively, while th...

Marker assisted pyramiding of Bph6 and Bph9 into elite restorer line 93–11 and development of functional marker for Bph9

OpenAIRE

Wang, Yang; Jiang, Weihua; Liu, Hongmei; Zeng, Ya; Du, Bo; Zhu, Lili; He, Guangcun; Chen, Rongzhi

2017-01-01

Background The brown planthopper (BPH) has become the most destructive and a serious threat to the rice production in Asia. Breeding the resistant varieties with improved host resistance is the most effective and ecosystem-friendly strategy of BPH biological management. As host resistance was always broken down by the presence of the upgrading BPH biotype, the more resistant varieties with novel resistance genes or pyramiding known identified BPH resistance genes would be needed urgently for ...

Brown colour in natural diamond and interaction between the brown related and other colour-inducing defects

International Nuclear Information System (INIS)

Fisher, D; Sibley, S J; Kelly, C J

2009-01-01

Absorption spectroscopy results on a range of type II diamonds are presented which enable the electronic states associated with them to be mapped out. High pressure, high temperature treatment of brown type IIa diamonds has enabled an activation energy for the removal of the brown colour of 8.0 ± 0.3 eV to be determined and this is consistent with expectations associated with the currently accepted vacancy cluster model for the defect. Theoretical calculations suggest that this defect will generate partially filled gap states about 1 eV above the valence band. Data on the photochromic behaviour of bands producing pink colour and their relation to brown colour are presented; these suggest that the pink bands are produced from two independent transitions with ground states close to each other just below the middle of the band gap. Compensation of neutral boron by charge transfer from states associated with brown colour is demonstrated via the correlated increase in neutral boron and decrease in brown colour on high pressure, high temperature treatment to remove the defects causing the brown colour.

Storage stability of flour-blasted brown rice

Science.gov (United States)

Brown rice was blasted with rice flour rather than sand in a sand blaster to make microscopic nicks and cuts so that water can easily penetrate into the brown rice endosperm and cook the rice in a shorter time. The flour-blasted American Basmati brown rice, long grain brown rice, and parboiled long...

7 CFR 29.2254 - Brown colors.

Science.gov (United States)

2010-01-01

... 7 Agriculture 2 2010-01-01 2010-01-01 false Brown colors. 29.2254 Section 29.2254 Agriculture Regulations of the Department of Agriculture AGRICULTURAL MARKETING SERVICE (Standards, Inspections, Marketing... colors. A group of colors ranging from a reddish brown to yellowish brown. These colors vary from low to...

Natural Inhibitors of Maillard Browning

Science.gov (United States)

2013-12-01

BREAD COLORING CHEESE SPREAD CHEMICAL REACTIONS FLAVOR OXIDATION DAIRY PRODUCTS...nutritional intake, and decrease waste due to non-consumption of sensory degraded ration components. 1.1 Maillard Browning Maillard browning, also

The browning kinetics of the non-enzymatic browning reaction in L-ascorbic acid/basic amino acid systems

Directory of Open Access Journals (Sweden)

Ai-Nong YU

Full Text Available Abstract Under the conditions of weak basis and the reaction temperature range of 110-150 °C, lysine, arginine and histidine were reacted with L-ascorbic acid at equal amount for 30-150 min, respectively and the formation of browning products was monitored with UV–vis spectrometry. The kinetic characteristics of their non-enzymatic browning reaction were investigated. The study results indicated that the non-enzymatic browning reaction of these three amino acids with L-ascorbic acid to form browning products was zero-order reaction. The apparent activation energies for the formation of browning products from L-ascorbic acid/lysine, L-ascorbic acid/arginine and L-ascorbic acid/histidine systems were 54.94, 50.08 and 35.31kJ/mol. The activation energy data indicated the degree of effects of reaction temperature on non-enzymatic browning reaction. Within the temperature range of 110-150 °C, the reaction rate of L-ascorbic acid/lysine system was the fastest one, followed by that of the L-ascorbic acid/arginine system. The reaction rate of L-ascorbic acid/histidine system was the slowest one. Based on the observed kinetic data, the formation mechanisms of browning products were proposed.

A preliminary molecular phylogeny of planthoppers (Hemiptera: Fulgoroidea based on nuclear and mitochondrial DNA sequences.

Directory of Open Access Journals (Sweden)

Nan Song

Full Text Available The planthopper superfamily Fulgoroidea (Insecta: Hemiptera is one of the most dominant groups of phytophagous insects. It comprises about 20 families, containing a total of 9000 species worldwide. Despite several recent studies, the phylogeny of Fulgoroidea is not yet satisfactorily resolved and the phylogenetic positions of several key families, especially Cixiidae, Delphacidae, Tettigometridae, Nogodinidae, Acanaloniidae and Issidae, are contentious. Here, we expand upon recent phylogenetic work using additional nuclear (18S and 28S and novel mitochondrial (16S and cytb markers. Maximum likelihood and Bayesian analyses yielded robust phylogenetic trees. In these topologies, a group containing Cixiidae and Delphacidae is recovered as the sister group to the remaining taxa. Tettigometridae is placed in a more nested position and is grouped with Caliscelidae. Sister relationships are found between Flatidae and Ricaniidae, and between Dictyopharidae and Fulgoridae. Nogodinidae and Issidae are confirmed to be non-monophyletic families. For major nodes of interest, divergence date estimates are generally older than those from the fossil record.

Symbiotic cornucopia of the monophagous planthopper Ommatidiotus dissimilis (Fallén, 1806) (Hemiptera: Fulgoromorpha: Caliscelidae).

Science.gov (United States)

Michalik, Anna; Szwedo, Jacek; Stroiński, Adam; Świerczewski, Dariusz; Szklarzewicz, Teresa

2018-03-07

In contrast to Cicadomorpha, in which numerous symbiotic bacteria have been identified and characterized, the symbionts of fulgoromorphans are poorly known. Here, we present the results of histological, ultrastructural, and molecular analyses of the symbiotic system of the planthopper Ommatidiotus dissimilis. Amplification, cloning, and sequencing of bacterial 16S RNA genes have revealed that O. dissimilis is host to five types of bacteria. Apart from bacteria Sulcia and Vidania, which are regarded as ancestral symbionts of Fulgoromorpha, three additional types of bacteria belonging to the genera Sodalis, Wolbachia, and Rickettsia have been detected. Histological and ultrastructural investigations have shown that bacteria Sulcia, Vidania, and Sodalis house separate bacteriocytes, whereas bacteria Wolbachia and Rickettsia are dispersed within various insect tissue. Additionally, bacteria belonging to the genus Vidania occupy the bacteriome localized in the lumen of the hindgut. Both molecular and microscopic analyses have revealed that all the symbionts are transovarially transmitted between generations.

Thyroid hormones induce browning of white fat

Science.gov (United States)

Martínez-Sánchez, Noelia; Moreno-Navarrete, José M; Contreras, Cristina; Rial-Pensado, Eva; Fernø, Johan; Nogueiras, Rubén; Diéguez, Carlos

2016-01-01

The canonical view about the effect of thyroid hormones (THs) on thermogenesis assumes that the hypothalamus acts merely as a modulator of the sympathetic outflow on brown adipose tissue (BAT). Recent data have challenged that vision by demonstrating that THs act on the ventromedial nucleus of the hypothalamus (VMH) to inhibit AMP-activated protein kinase (AMPK), which regulates the thermogenic program in BAT, leading to increased thermogenesis and weight loss. Current data have shown that in addition to activation of brown fat, the browning of white adipose tissue (WAT) might also be an important thermogenic mechanism. However, the possible central effects of THs on the browning of white fat remain unclear. Here, we show that 3,3′,5,5′ tetraiodothyroxyne (T4)-induced hyperthyroidism promotes a marked browning of WAT. Of note, central or VMH-specific administration of 3,3′,5-triiodothyronine (T3) recapitulates that effect. The specific genetic activation of hypothalamic AMPK in the VMH reversed the central effect of T3 on browning. Finally, we also showed that the expression of browning genes in human WAT correlates with serum T4. Overall, these data indicate that THs induce browning of WAT and that this mechanism is mediated via the central effects of THs on energy balance. PMID:27913573

Tune Your Brown Clustering, Please

DEFF Research Database (Denmark)

Derczynski, Leon; Chester, Sean; Bøgh, Kenneth Sejdenfaden

2015-01-01

Brown clustering, an unsupervised hierarchical clustering technique based on ngram mutual information, has proven useful in many NLP applications. However, most uses of Brown clustering employ the same default configuration; the appropriateness of this configuration has gone predominantly...

Influence of selected factors on browning of Camembert cheese.

Science.gov (United States)

Carreira, Alexandra; Dillinger, Klaus; Eliskases-Lechner, Frieda; Loureiro, Virgílio; Ginzinger, Wolfgang; Rohm, Harald

2002-05-01

Experimental Camembert cheeses were made to investigate the effects on browning of the following factors: inoculation with Yarrowia lipolytica, the use of Penicillium candidum strains with different proteolytic activity, the addition of tyrosine, and the addition of Mn2+ thus leading to 16 different variants of cheese. Two physical colour parameters were used to describe browning, depending on the location in the cheeses: a whiteness index for the outside browning (mould mycelium), and a brownness index for the inside browning (surface of the cheese body). Mn2+ promoted a significant increase of browning at both locations, whereas Yar. lipolytica had the opposite effect. Outside browning was significantly more intense when using the Pen. candidum strain with higher proteolytic activity. A significant interaction was found between Yar. lipolytica and Pen. candidum. The yeast had no effect in combination with a low proteolytic strain of Pen. candidum, but significantly reduced proteolysis and browning in combination with a high proteolytic strain of Pen. candidum. We further confirmed that both strains of Pen. candidum were able to produce brown pigments from tyrosine and thus both are presumably responsible for the browning activity in this type of cheese.

Brown coal gasification made easy

International Nuclear Information System (INIS)

Hamilton, Chris

2006-01-01

Few Victorians will be aware that gas derived from coal was first used in 1849 to provide lighting in a baker's shop in Swanston Street, long before electric lighting came to the State. The first commercial 'gas works' came on stream in 1856 and Melbourne then had street lighting run on gas. By 1892 there were 50 such gas works across the State. Virtually all were fed with black coal imported from New South Wales. Brown coal was first discovered west of Melbourne in 1857, and the Latrobe Valley deposits were identified in the early 1870s. Unfortunately, such wet brown coal did not suit the gas works. Various attempts to commercialise Victorian brown coal met with mixed success as it struggled to compete with imported New South Wales black coal. In June 1924 Yallourn A transmitted the first electric power to Melbourne, and thus began the Latrobe Valley's long association with generating electric power from brown coal. Around 1950, the Metropolitan Gas Company applied for financial assistance to build a towns gas plant using imported German gasification technology which had been originally designed for a brown coal briquette feed. The State Government promptly acquired the company and formed the Gas and Fuel Corporation. The Morwell Gasification Plant was opened on 9 December 1956 and began supplying Melbourne with medium heating value towns gas

Cry64Ba and Cry64Ca, Two ETX/MTX2-Type Bacillus thuringiensis Insecticidal Proteins Active against Hemipteran Pests.

Science.gov (United States)

Liu, Yonglei; Wang, Yinglong; Shu, Changlong; Lin, Kejian; Song, Fuping; Bravo, Alejandra; Soberón, Mario; Zhang, Jie

2018-02-01

Genetically modified crops that express insecticidal Bacillus thuringiensis (Bt) proteins have become a primary approach for control of lepidopteran (moth) and coleopteran (beetle) pests that feed by chewing the plants. However, the sap-sucking insects (Hemiptera) are not particularly susceptible to Bt toxins. In this study, we describe two Cry toxins (Cry64Ba and Cry64Ca) from Bt strain 1012 that showed toxicity against two important hemipteran rice pests, Laodelphax striatellus and Sogatella furcifera Both of these proteins contain an ETX/MTX2 domain and share common sequence features with the β-pore-forming toxins. Coexpression of cry64Ba and cry64Ca genes in the acrystalliferous Bt strain HD73 - resulted in high insecticidal activity against both hemipteran pests. No toxicity was observed on other pests such as Ostrinia furnacalis , Plutella xylostella , or Colaphellus bowringi Also, no hemolytic activity or toxicity against cancer cells was detected. Binding assays showed specific binding of the Cry64Ba/Cry64Ca toxin complex to brush border membrane vesicles isolated from L. striatellus Cry64Ba and Cry64Ca are Bt Cry toxins highly effective against hemipteran pests and could provide a novel strategy for the environmentally friendly biological control of rice planthoppers in transgenic plants. IMPORTANCE In Asia, rice is an important staple food, whose production is threatened by rice planthoppers. To date, no effective Bacillus thuringiensis (Bt) protein has been shown to have activity against rice planthoppers. We cloned two Bt toxin genes from Bt strain 1012 that showed toxicity against small brown planthoppers ( Laodelphax striatellus ) and white-backed planthoppers ( Sogatella furcifera ). To our knowledge, the proteins encoded by the cry64Ba and cry64Ca genes are the most efficient insecticidal Bt Cry proteins with activity against hemipteran insects reported so far. Cry64Ba and Cry64Ca showed no toxicity against some lepidopteran or coleopteran pests

Lethal mutation of internal irradiation brown planthopper (Nilaparvita lugens Stal)

International Nuclear Information System (INIS)

Wahid, R.A.

1988-01-01

The moulting IVth of BPH nympha were irradiated internally with radiophosphorous 32-P 1 uCi/ml, 10 uCi/ml, 50 uCi/ml, 100 uCi/ml, and 500 uCi/ml concentrations respectivelly. An observation was carried out to determines heredity of hopper sterilities from the mating groups of R male x N female, R male x R female, and N male x R female. The 32-P concentration below of 50 uCi/ml seemed to be the substerile dose, however, the dominant lethal mutation has been visually shown by R male x R female F1 mating group. The hereditary lines of F1, F2, F3, and F4 of the hopper sterilities wich were indicated by the nympha hatch ability have some significant correlations (r1= -0.77, r2= -0.92, r3= -0.93 and r4= -0.85). Thus, the resesif lethal mutations visually showed by F3 and F4 from all of the 100 uCi/ml and 50 uCi/ml treated groups. (author). 10 refs, 2 figs, 2 tabs

Generalised Brown Clustering and Roll-up Feature Generation

DEFF Research Database (Denmark)

Derczynski, Leon; Chester, Sean

2016-01-01

active set size. Moreover, the generalisation permits a novel approach to feature selection from Brown clusters: We show that the standard approach of shearing the Brown clustering output tree at arbitrary bitlengths is lossy and that features should be chosen instead by rolling up Generalised Brown...

Searching for chemical signatures of brown dwarf formation

Science.gov (United States)

Maldonado, J.; Villaver, E.

2017-06-01

Context. Recent studies have shown that close-in brown dwarfs in the mass range 35-55 MJup are almost depleted as companions to stars, suggesting that objects with masses above and below this gap might have different formation mechanisms. Aims: We aim to test whether stars harbouring massive brown dwarfs and stars with low-mass brown dwarfs show any chemical peculiarity that could be related to different formation processes. Methods: Our methodology is based on the analysis of high-resolution échelle spectra (R 57 000) from 2-3 m class telescopes. We determine the fundamental stellar parameters, as well as individual abundances of C, O, Na, Mg, Al, Si, S, Ca, Sc, Ti, V, Cr, Mn, Co, Ni, and Zn for a large sample of stars known to have a substellar companion in the brown dwarf regime. The sample is divided into stars hosting massive and low-mass brown dwarfs. Following previous works, a threshold of 42.5 MJup was considered. The metallicity and abundance trends of the two subsamples are compared and set in the context of current models of planetary and brown dwarf formation. Results: Our results confirm that stars with brown dwarf companions do not follow the well-established gas-giant planet metallicity correlation seen in main-sequence planet hosts. Stars harbouring massive brown dwarfs show similar metallicity and abundance distribution as stars without known planets or with low-mass planets. We find a tendency of stars harbouring less-massive brown dwarfs of having slightly higher metallicity, [XFe/Fe] values, and abundances of Sc II, Mn I, and Ni I than the stars having the massive brown dwarfs. The data suggest, as previously reported, that massive and low-mass brown dwarfs might present differences in period and eccentricity. Conclusions: We find evidence of a non-metallicity dependent mechanism for the formation of massive brown dwarfs. Our results agree with a scenario in which massive brown dwarfs are formed as stars. At high metallicities, the core

L-rhamnose induces browning in 3T3-L1 white adipocytes and activates HIB1B brown adipocytes.

Science.gov (United States)

Choi, Minji; Mukherjee, Sulagna; Kang, Nam Hyeon; Barkat, Jameel Lone; Parray, Hilal Ahmad; Yun, Jong Won

2018-04-11

Induction of the brown adipocyte-like phenotype in white adipocytes (browning) is considered as a novel strategy to fight obesity due to the ability of brown adipocytes to increase energy expenditure. Here, we report that L-rhamnose induced browning by elevating expression levels of beige-specific marker genes, including Cd137, Cited1, Tbx1, Prdm16, Tmem26, and Ucp1, in 3T3-L1 adipocytes. Moreover, L-rhamnose markedly elevated expression levels of proteins involved in thermogenesis both in 3T3-L1 white and HIB1B brown adipocytes. L-rhamnose treatment in 3T3-L1 adipocytes also significantly elevated protein levels of p-HSL, p-AMPK, ACOX, and CPT1 as well as reduced levels of ACC, FAS, C/EBPα, and PPARγ, suggesting its possible role in enhancement of lipolysis and lipid catabolism as well as reduced adipogenesis and lipogenesis, respectively. The quick technique of efficient molecular docking provided insight into the strong binding of L-rhamnose to the fat-digesting glycine residue of β 3 -adrenergic receptor (AR), indicating strong involvement of L-rhamnose in fat metabolism. Further examination of the molecular mechanism of L-rhamnose revealed that it induced browning of 3T3-L1 adipocytes via coordination of multiple signaling pathways through β 3 -AR, SIRT1, PKA, and p-38. To the best of our knowledge, this is the first study to demonstrate that L-rhamnose plays multiple modulatory roles in the induction of white fat browning, activation of brown adipocytes, as well as promotion of lipid metabolism, thereby demonstrating its therapeutic potential for treatment of obesity. © 2018 IUBMB Life, 2018. © 2018 International Union of Biochemistry and Molecular Biology.

Isolation of glycoproteins from brown algae

DEFF Research Database (Denmark)

2015-01-01

The present invention relates to a novel process for the isolation of unique anti-oxidative glycoproteins from the pH precipitated fractions of enzymatic extracts of brown algae. Two brown seaweeds viz, Fucus serratus and Fucus vesiculosus were hydrolysed by using 3 enzymes viz, Alcalase, Viscozyme...

Trustworthy-looking face meets brown eyes.

Directory of Open Access Journals (Sweden)

Karel Kleisner

Full Text Available We tested whether eye color influences perception of trustworthiness. Facial photographs of 40 female and 40 male students were rated for perceived trustworthiness. Eye color had a significant effect, the brown-eyed faces being perceived as more trustworthy than the blue-eyed ones. Geometric morphometrics, however, revealed significant correlations between eye color and face shape. Thus, face shape likewise had a significant effect on perceived trustworthiness but only for male faces, the effect for female faces not being significant. To determine whether perception of trustworthiness was being influenced primarily by eye color or by face shape, we recolored the eyes on the same male facial photos and repeated the test procedure. Eye color now had no effect on perceived trustworthiness. We concluded that although the brown-eyed faces were perceived as more trustworthy than the blue-eyed ones, it was not brown eye color per se that caused the stronger perception of trustworthiness but rather the facial features associated with brown eyes.

Síndrome de Brown inflamatória: relato de caso Inflammatory Brown syndrome: case report

Directory of Open Access Journals (Sweden)

Leonardo Guedes Candido Marculino

2010-08-01

Full Text Available A síndrome de Brown enquadra-se no grupo de estrabismos restritivos e é causada pela limitação de movimento do tendão do oblíquo superior através da tróclea. Caracteriza-se por ortotropia ou hipotropia na primária do olhar, limitação ou ausência de elevação em adução, frequente depressão do olho em adução com anisotropia em V e dução passiva positiva na elevação em adução. Denomina-se síndrome de Brown inflamatória, o distúrbio secundário, que tem como principais causas inflamações locais na órbita e doenças inflamatórias como artrite reumatóide e tenossinovite. Apresentamos o caso de um paciente de 44 anos, do sexo masculino, com queixa de diplopia binocular vertical à dextroversão recorrente. Diagnosticado como síndrome de Brown inflamatória sem etiologia definida, confirmada por ressonância nuclear magnética e com resolução espontânea.Brown syndrome fits the group of restrictive strabismus and is caused by a movement limitation of the superior oblique tendon through the trochlea. It is characterized by parallelism in the primary gaze position, limitation or absence of elevation in adduction, frequent depression of the eye in adduction with anisotropy in V-pattern and positive passive duction in the elevation in adduction. It is called inflammatory Brown syndrome, a secondary disorder, which main causes are local inflammation in the orbit and inflammatory diseases such as rheumatoid arthritis and tenosynovitis. A case of a 44 year-old patient, male, complaining of binocular vertical diplopia due to recurring dextroversion is reported. It was diagnosed as inflammatory Brown syndrome of uncertain etiology, confirmed by magnetic nuclear resonance, and with spontaneous resolution.

Thermochemical modelling of brown dwarf discs

NARCIS (Netherlands)

Greenwood, A. J.; Kamp, I.; Waters, L. B. F. M.; Woitke, P.; Thi, W.-F.; Rab, Ch.; Aresu, G.; Spaans, M.

The physical properties of brown dwarf discs, in terms of their shapes and sizes, are still largely unexplored by observations. ALMA has by far the best capabilities to observe these discs in sub-mm CO lines and dust continuum, while also spatially resolving some discs. To what extent brown dwarf

Buprofezin susceptibility survey, resistance selection and preliminary determination of the resistance mechanism in Nilaparvata lugens (Homoptera: Delphacidae).

Science.gov (United States)

Wang, Yanhua; Gao, Congfen; Xu, Zhiping; Zhu, Yu Cheng; Zhang, Jiushuang; Li, Wenhong; Dai, Dejiang; Lin, Youwei; Zhou, Weijun; Shen, Jinliang

2008-10-01

Buprofezin has been used for many years to control Nilaparvata lugens (Stål). Assessment of susceptibility change in the insect is essential for maintaining control efficiency and resistance management. Eleven-year surveys showed that most field populations were susceptible before 2004. However, substantially higher levels of resistance (up to 28-fold) were found in most of the rice fields in China after 2004. A field population was collected and periodically selected for buprofezin resistance in the laboratory. After 65 generations (56 were selected), the colony successfully obtained 3599-fold resistance to buprofezin. Synergism tests showed that O,O-diethyl-O-phenyl phosphorothioate (SV1), piperonyl butoxide (PBO) and diethyl maleate (DEM) increased buprofezin toxicity in the resistant strain by only 1.5-1.6 fold, suggesting that esterases, P450-monooxygenases and glutathione S-transferases had no substantial effect on buprofezin resistance development. The results from this study indicate that N. lugens has the potential to develop high resistance to buprofezin. A resistance management program with rotation of buprofezin and other pesticides may efficiently delay or slow down resistance development in the insect. Further investigation is also necessary to understand the resistance mechanisms in N. lugens.

Production of blast furnace coke from soft brown coal

Energy Technology Data Exchange (ETDEWEB)

Scholz, G.; Wundes, H.; Schkommodau, F.; Zinke, H.-G. (VEB Gaskombinat Schwarze Pumpe (German Democratic Republic))

1988-01-01

Reviews experimental production and utilization of high quality brown coal coke in the GDR during 1985 and 1986. The technology of briquetting and coking brown coal dust is described; the superior parameters of produced coke quality are listed in comparison to those of regular industrial coke made from brown and black coal. Dust emission from high quality brown coal coke was suppressed by coke surface treatment with dispersion foam. About 4,200 t of this coke were employed in black coal coke substitution tests in a blast furnace. Substitution rate was 11%, blast furnace operation was positive, a substitution factor of 0.7 t black coal coke per 1 t of brown coal coke was calculated. Technology development of high quality brown coal coke production is regarded as complete; blast furnace coke utilization, however, requires further study. 8 refs.

Significance of the tropical fire ant Solenopsis geminata (hymenoptera: formicidae) as part of the natural enemy complex responsible for successful biological control of many tropical irrigated rice pests.

Science.gov (United States)

Way, M J; Heong, K L

2009-10-01

The tropical fire ant Solenopsis geminata (Fabricius) often nests very abundantly in the earthen banks (bunds) around irrigated rice fields in the tropics. Where some farmers habitually drain fields to the mud for about 3-4 days, the ants can quickly spread up to about 20 m into the fields where they collect food, including pest prey such as the eggs and young of the apple snail Pomacea caniculata (Lamarck) and insects such as lepidopterous larvae and hoppers, notably Nilaparvata lugens (Stäl) the brown planthopper (Bph) and green leafhoppers Nephotettix spp. Even in drained fields, the activity of S. geminata is restricted by rainfall in the wet season. The relatively few ant workers that forage characteristically into drained fields and on to the transplanted clumps of rice plants (hills) kill the normally few immigrant Bph adults but are initially slower acting than other species of the natural enemy complex. However, larger populations of Bph are fiercely attacked and effectively controlled by rapidly recruited ant workers; whereas, in the absence of the ant, the other natural enemies are inadequate. In normal circumstances, there is no ant recruitment in response to initially small populations of immigrant Bph and no evidence of incompatibility between ant foragers and other natural enemies such as spiders. However, when many ants are quickly and aggressively recruited to attack large populations of Bph, they temporarily displace some spiders from infested hills. It is concluded that, in suitable weather conditions and even when insecticides kill natural enemies within the rice field, periodic drainage that enables S. geminata to join the predator complex is valuable for ant-based control of pests such as snails and Lepidoptera, and especially against relatively large populations of Bph. Drainage practices to benefit ants are fully compatible with recent research, which shows that periodic drainage combats problems of 'yield decline' in intensively irrigated

The brown coal. Present state and development perspectives

International Nuclear Information System (INIS)

Wagenknecht, J.

1994-01-01

A present state of Polish power plants fueled by brown coal is presented. Their economic results are compared with the achievements of power stations fueled by black coal. The basic data concerning brown coal reserves, production and consumption are given. The problems of environmental protection are discussed. The different applications of brown coal are mentioned. Its importance for energy balance is stressed. 6 tabs

The brown dwarf kinematics project

Science.gov (United States)

Faherty, Jackie K.

2010-10-01

Brown dwarfs are a recent addition to the plethora of objects studied in Astronomy. With theoretical masses between 13 and 75 MJupiter , they lack sustained stable Hydrogen burning so they never join the stellar main sequence. They have physical properties similar to both planets and low-mass stars so studies of their population inform on both. The distances and kinematics of brown dwarfs provide key statistical constraints on their ages, moving group membership, absolute brightnesses, evolutionary trends, and multiplicity. Yet, until my thesis, fundamental measurements of parallax and proper motion were made for only a relatively small fraction of the known population. To address this deficiency, I initiated the Brown Dwarf Kinematics (BDKP). Over the past four years I have re-imaged the majority of spectroscopically confirmed field brown dwarfs (or ultracool dwarfs---UCDs) and created the largest proper motion catalog for ultracool dwarfs to date. Using new astrometric information I examined population characteristics such as ages calculated from velocity dispersions and correlations between kinematics and colors. Using proper motions, I identified several new wide co-moving companions and investigated binding energy (and hence formation) limitations as well as the frequency of hierarchical companions. Concurrently over the past four years I have been conducting a parallax survey of 84 UCDs including those showing spectral signatures of youth, metal-poor brown dwarfs, and those within 20 pc of the Sun. Using absolute magnitude relations in J,H, and K, I identified overluminous binary candidates and investigated known flux-reversal binaries. Using current evolutionary models, I compared the MK vs J-K color magnitude diagram to model predictions and found that the low-surface gravity dwarfs are significantly red-ward and underluminous of predictions and a handful of late-type T dwarfs may require thicker clouds to account for their scatter.

Estrogenic effects of phytoestrogens in brown trout (Salmo trutta)

DEFF Research Database (Denmark)

Nielsen, Louise Marie; Holbech, Henrik; Bjerregaard, Poul

2010-01-01

, the potential effect of the waterborne phytoestrogens on endemic fish species is largely unknown. In the present investigation, the estrogenic effect of biochanin A was tested in brown trout through water exposure experiments. Juvenile brown trout of both sexes were exposed to different concentrations...... of biochanin A. In a ten day exposure experiments, NOEC and LOEC for plasma vitellogenin induction in brown trout were found to be 0.8µg biochanin A/L and 1.2µg biochanin A/L, respectively. A six hour pulse experiment resulted in NOEC and LOEC for induction of plasma vitellogenin in brown trout of 48µg...... biochanin A/L and 186µg biochanin A/L, respectively. Investigations of the ability of genistein to induce vitellogenin synthesis in brown trout are ongoing....

Phylogeography of mitochondrial DNA variation in brown bears and polar bears.

Science.gov (United States)

Shields, G F; Adams, D; Garner, G; Labelle, M; Pietsch, J; Ramsay, M; Schwartz, C; Titus, K; Williamson, S

2000-05-01

We analyzed 286 nucleotides of the middle portion of the mitochondrial cytochrome b gene of 61 brown bears from three locations in Alaska and 55 polar bears from Arctic Canada and Arctic Siberia to test our earlier observations of paraphyly between polar bears and brown bears as well as to test the extreme uniqueness of mitochondrial DNA types of brown bears on Admiralty, Baranof, and Chichagof (ABC) islands of southeastern Alaska. We also investigated the phylogeography of brown bears of Alaska's Kenai Peninsula in relation to other Alaskan brown bears because the former are being threatened by increased human development. We predicted that: (1) mtDNA paraphyly between brown bears and polar bears would be upheld, (2) the mtDNA uniqueness of brown bears of the ABC islands would be upheld, and (3) brown bears of the Kenai Peninsula would belong to either clade II or clade III of brown bears of our earlier studies of mtDNA. All of our predictions were upheld through the analysis of these additional samples. Copyright 2000 Academic Press.

Phylogeography of mitochondrial DNA variation in brown bears and polar bears

Science.gov (United States)

Shields, Gerald F.; Adams, Deborah; Garner, Gerald W.; Labelle, Martine; Pietsch, Jacy; Ramsay, Malcolm; Schwartz, Charles; Titus, Kimberly; Williamson, Scott

2000-01-01

We analyzed 286 nucleotides of the middle portion of the mitochondrial cytochrome b gene of 61 brown bears from three locations in Alaska and 55 polar bears from Arctic Canada and Arctic Siberia to test our earlier observations of paraphyly between polar bears and brown bears as well as to test the extreme uniqueness of mitochondrial DNA types of brown bears on Admiralty, Baranof, and Chichagof (ABC) islands of southeastern Alaska. We also investigated the phylogeography of brown bears of Alaska's Kenai Peninsula in relation to other Alaskan brown bears because the former are being threatened by increased human development. We predicted that: (1) mtDNA paraphyly between brown bears and polar bears would be upheld, (2) the mtDNA uniqueness of brown bears of the ABC islands would be upheld, and (3) brown bears of the Kenai Peninsula would belong to either clade II or clade III of brown bears of our earlier studies of mtDNA. All of our predictions were upheld through the analysis of these additional samples.

Browning phenomenon of medieval stained glass windows.

Science.gov (United States)

Ferrand, Jessica; Rossano, Stéphanie; Loisel, Claudine; Trcera, Nicolas; van Hullebusch, Eric D; Bousta, Faisl; Pallot-Frossard, Isabelle

2015-04-07

In this work, three pieces of historical on-site glass windows dated from the 13th to 16th century and one archeological sample (8th century) showing Mn-rich brown spots at their surface or subsurface have been characterized by optical microscopy and Scanning Electron Microscopy coupled with Energy Dispersive X-ray spectroscopy. The oxidation state of Mn as well as the Mn environment in the alteration phase have been characterized by X-ray absorption spectroscopy at the Mn K-edge. Results show that the oxidation state of Mn and therefore the nature of the alteration phase varies according to the sample considered and is correlated with the extent of the brown alteration. The larger the brown areas the more oxidized the Mn. However, by contrast with literature, the samples presenting the more extended brown areas are not similar to pyrolusite and contain Mn mainly under a (+III) oxidation state.

Brown Recluse Spider

Science.gov (United States)

... to a group of spiders commonly known as violin spiders or fiddlebacks. The characteristic fiddle-shaped pattern ... 4-19.1mm) • Color: Golden brown • A dark violin/fiddle shape (see top photo) is located on ...

Browns Ferry

International Nuclear Information System (INIS)

Wood, J.

1996-01-01

In 1986, the US Nuclear Regulatory Commission (NRC) established a ''watch list'' of power reactors requiring special attention which included the three BWR units at Brown's Ferry owned by the Tennessee Valley Authority (TVA). The reactors has been closed down voluntarily by the TVA in 1985 in order to deal with a backlog of maintenance and regulatory issues. Intended as short-term, the shutdown was indefinitely extended when the nature and extent of the design changes, accompanying documentation and retrofitting required to satisfy the NRC became apparent. The recovery programme for Unit 2 was completed by 1991 and the reactor returned to service under a dedicated operating staff. Meanwhile, a separate, dedicated, recovery team was set up to manage Unit 3 which was returned to service in December 1995. Browns Ferry 2 was removed from the NRC watch list in June 1992 and Units 1 and 3 in June 1996. Units 2 and 3 have both operated successfully since restart but Unit 1 is currently mothballed and TVA has no plans to bring it back into service. (UK)

Phytochemical Profile of Brown Rice and Its Nutrigenomic Implications

Directory of Open Access Journals (Sweden)

Keneswary Ravichanthiran

2018-05-01

Full Text Available Whole grain foods have been promoted to be included as one of the important components of a healthy diet because of the relationship between the regular consumption of whole-grain foods and reduced risk of chronic diseases. Rice is a staple food, which has been widely consumed for centuries by many Asian countries. Studies have suggested that brown rice is associated with a wide spectrum of nutrigenomic implications such as anti-diabetic, anti-cholesterol, cardioprotective and antioxidant. This is because of the presence of various phytochemicals that are mainly located in bran layers of brown rice. Therefore, this paper is a review of publications that focuses on the bioactive compounds and nutrigenomic implications of brown rice. Although current evidence supports the fact that the consumption of brown rice is beneficial for health, these studies are heterogeneous in terms of their brown rice samples used and population groups, which cause the evaluation to be difficult. Future clinical studies should focus on the screening of individual bioactive compounds in brown rice with reference to their nutrigenomic implications.

Search for brown dwarfs in the IRAS data bases

International Nuclear Information System (INIS)

Low, F.J.

1986-01-01

A report is given on the initial searches for brown dwarf stars in the IRAS data bases. The paper was presented to the workshop on 'Astrophysics of brown dwarfs', Virginia, USA, 1985. To date no brown dwarfs have been discovered in the solar neighbourhood. Opportunities for future searches with greater sensitivity and different wavelengths are outlined. (U.K.)

Mesoionic Pyrido[1,2-a]pyrimidinone Insecticides: From Discovery to Triflumezopyrim and Dicloromezotiaz.

Science.gov (United States)

Zhang, Wenming

2017-09-19

One of the greatest global challenges is to feed the ever-increasing world population. The agrochemical tools growers currently utilize are also under continuous pressure, due to a number of factors that contribute to the loss of existing products. Mesoionic pyrido[1,2-a]pyrimidinones are an unusual yet very intriguing class of compounds. Known for several decades, this class of compounds had not been systemically studied until we started our insecticide discovery program. This Account provides an overview of the efforts on mesoionic pyrido[1,2-a]pyridinone insecticide discovery, beginning from the initial high throughput screen (HTS) discovery to ultimate identification of triflumezopyrim (4, DuPont Pyraxalt) and dicloromezotiaz (5) for commercialization as novel insecticides. Mesoionic pyrido[1,2-a]pyrimidinones with a n-propyl group at the 1-position, such as compound 1, were initially isolated as undesired byproducts from reactions for a fungicide discovery program at DuPont Crop Protection. Such compounds showed interesting insecticidal activity in a follow-up screen and against an expanded insect species list. The area became an insecticide hit for exploration and then a lead area for optimization. At the lead optimization stage, variations at three regions of compound 1, i.e., side-chain (n-propyl group), substituents on the 3-phenyl group, and substitutions on the pyrido- moiety, were explored with many analogues prepared and evaluated. Breakthrough discoveries included replacing the n-propyl group with a 2,2,2-trifluoroethyl group to generate compound 2, and then with a 2-chlorothiazol-5-ylmethyl group to form compound 3. 3 possesses potent insecticidal activity not only against a group of hopper species, including corn planthopper (Peregrinus maidis (Ashmead), CPH) and potato leafhopper (Empoasca fabae (Harris), PLH), as well as two key rice hopper species, namely, brown planthopper (Nilaparvata lugens (Stål), BPH) and rice green leafhopper (Nephotettix

Exposure of Brown Recluse and Brown Widow Spiders (Araneae: Sicariidae, Theridiidae) to a Commercial Sulfuryl Fluoride Fumigation.

Science.gov (United States)

Vetter, Richard S; Hoddle, Mark S; Choe, Dong-Hwan; Thoms, Ellen

2014-10-01

The body of pesticide research on spiders is sparse with most studies using topical or residual applications to assess efficacy. Data on the effects of fumigation on spider survivorship are scarce in the scientific literature. In this study, we exposed adult male and female brown recluse spiders, Loxosceles reclusa Gertsch & Mulaik, and female brown widow spiders, Latrodectus geometricus C. L. Koch, to a commercial fumigation event using sulfuryl fluoride directed at termite control. General consensus from the pest control industry is that fumigation is not always effective for control of spiders for a variety of reasons, including insufficient fumigant dosage, particularly, for contents of egg sacs that require a higher fumigant dosage for control. We demonstrated that a sulfuryl fluoride fumigation with an accumulated dosage of 162 oz-h per 1,000 ft(3) at 21°C over 25 h (≈1.7 × the drywood termite dosage) directed at termites was sufficient to kill adult brown recluse and brown widow spiders. The effectiveness of commercial fumigation practices to control spiders, and particularly their egg sacs, warrants further study. © 2014 Entomological Society of America.

Mink predation on brown trout in a Black Hills stream

Science.gov (United States)

Davis, Jacob L.; Wilhite, Jerry W.; Chipps, Steven R.

2016-01-01

In the early 2000’s, declines in the brown trout (Salmo trutta) fishery in Rapid Creek, South Dakota, caused concern for anglers and fisheries managers. We conducted a radio telemetry study in 2010 and 2011 to identify predation mortality associated with mink, using hatchery-reared (2010) or wild (2011) brown trout. Estimated predation rates by mink (Mustela vison) on radio-tagged brown trout were 30% for hatchery fish and 32% for wild fish. Size frequency analysis revealed that the size distribution of brown trout lost to predation was similar to that of other, radio-tagged brown trout. In both years, a higher proportion of predation mortality (83–92%) occurred during spring, consistent with seasonal fish consumption by mink. Predation by mink appeared to be a significant source of brown trout mortality in our study.

Properties of sorbents from brown coal

Energy Technology Data Exchange (ETDEWEB)

Straka, P.; Buchtele, J. [Academy of Sciences of the Czech Republic, Prague (Czech Republic)

2000-07-01

The surface and sorptional properties of carbonaceous materials prepared from brown coal and their relation to minerals content and coal bulk density as technologically important parameters of starting coal were described. Chars were prepared from brown coal of North Bohemian Brown Coal District and activated with CO{sub 2} in a large-scale laboratory unit. Their surface and sorptive properties were investigated. It was found that mineral matter/ash content favourably affects the mesoporosity development in chars/activated chars as the sorption capacity increased with increasing ash content in chars. No influence of ash content on the macroporosity was observed. With the activated chars, both the inner surface and sorption capacity showed the maximum in the burn-off range of 41-64%. Optimization of the process is discussed.

EVIDENCE FOR ACCRETION IN A NEARBY, YOUNG BROWN DWARF

International Nuclear Information System (INIS)

Reiners, Ansgar

2009-01-01

We report on the discovery of the young, nearby, brown dwarf 2MASS J0041353-562112. The object has a spectral type of M7.5; it shows Li absorption and signatures of accretion, which implies that it still has a disk and suggests an age below 10 Myr. The space motion vector and position on the sky indicate that the brown dwarf is probably a member of the ∼20 Myr old Tuc-Hor association, or that it may be an ejected member of the ∼12 Myr old β Pic association; both would imply that 2MASS J0041353-562112 may in fact be older than 10 Myr. No accreting star or brown dwarf was previously known in these associations. Assuming an age of 10 Myr, the brown dwarf has a mass of about 30 M Jup and is located at 35 pc distance. The newly discovered object is the closest accreting brown dwarf known. Its membership to an association older than 10 Myr implies that either disks in brown dwarfs can survive as long as in more massive stars, perhaps even longer, or that star formation in Tuc-Hor or β Pic occurred more recently than previously thought. The history and evolution of this object can provide new fundamental insight into the formation process of stars, brown dwarfs, and planets.

Fermented Brown Rice Flour as Functional Food Ingredient

OpenAIRE

Ilowefah, Muna; Chinma, Chiemela; Bakar, Jamilah; Ghazali, Hasanah; Muhammad, Kharidah; Makeri, Mohammad

2014-01-01

As fermentation could reduce the negative effects of bran on final cereal products, the utilization of whole-cereal flour is recommended, such as brown rice flour as a functional food ingredient. Therefore, this study aimed to investigate the effect of fermented brown rice flour on white rice flour, white rice batter and its steamed bread qualities. Brown rice batter was fermented using commercial baker?s yeast (Eagle brand) according to the optimum conditions for moderate acidity (pH 5.5) to...

SURPRISINGLY WEAK MAGNETISM ON YOUNG ACCRETING BROWN DWARFS

International Nuclear Information System (INIS)

Reiners, A.; Basri, G.; Christensen, U. R.

2009-01-01

We have measured the surface magnetic flux on four accreting young brown dwarfs and one nonaccreting young very low mass (VLM) star utilizing high-resolution spectra of absorption lines of the FeH molecule. A magnetic field of 1-2 kG had been proposed for one of the brown dwarfs, Two Micron All Sky Survey (2MASS) J1207334-393254, because of its similarities to higher mass T Tauri stars as manifested in accretion and the presence of a jet. We do not find clear evidence for a kilogauss field in any of our young brown dwarfs but do find a 2 kG field on the young VLM star. Our 3σ upper limit for the magnetic flux in 2MASS J1207334-393254 just reaches 1 kG. We estimate the magnetic field required for accretion in young brown dwarfs given the observed rotations, and find that fields of only a few hundred gauss are sufficient for magnetospheric accretion. This predicted value is less than our observed upper limit. We conclude that magnetic fields in young brown dwarfs are a factor of 5 or more lower than in young stars of about one solar mass, and in older stars with spectral types similar to our young brown dwarfs. It is interesting that, during the first few million years, the fields scale down with mass in line with what is needed for magnetospheric accretion, yet no such scaling is observed at later ages within the same effective temperature range. This scaling is opposite to the trend in rotation, with shorter rotation periods for very young accreting brown dwarfs compared with accreting solar-mass objects (and very low Rossby numbers in all cases). We speculate that in young objects a deeper intrinsic connection may exist between magnetospheric accretion and magnetic field strength, or that magnetic field generation in brown dwarfs may be less efficient than in stars. Neither of these currently has an easy physical explanation.

TOR Pathway-Mediated Juvenile Hormone Synthesis Regulates Nutrient-Dependent Female Reproduction in Nilaparvata lugens (Stål).

Science.gov (United States)

Lu, Kai; Chen, Xia; Liu, Wen-Ting; Zhou, Qiang

2016-03-28

The "target of rapamycin" (TOR) nutritional signaling pathway and juvenile hormone (JH) regulation of vitellogenesis has been known for a long time. However, the interplay between these two pathways regulating vitellogenin (Vg) expression remains obscure. Here, we first demonstrated the key role of amino acids (AAs) in activation of Vg synthesis and egg development in Nilaparvata lugens using chemically defined artificial diets. AAs induced the expression of TOR and S6K (S6 kinase), whereas RNAi-mediated silencing of these two TOR pathway genes and rapamycin application strongly inhibited the AAs-induced Vg synthesis. Furthermore, knockdown of Rheb (Ras homologue enriched in brain), TOR, S6K and application of rapamycin resulted in a dramatic reduction in the mRNA levels of jmtN (juvenile hormone acid methyltransferase, JHAMT). Application of JH III on the RNAi (Rheb and TOR) and rapamycin-treated females partially rescued the Vg expression. Conversely, knockdown of either jmtN or met (methoprene-tolerant, JH receptor) and application of JH III had no effects on mRNA levels of Rheb, TOR and S6K and phosphorylation of S6K. In summary, our results demonstrate that the TOR pathway induces JH biosynthesis that in turn regulates AAs-mediated Vg synthesis in N. lugens.

Browns Ferry fire

International Nuclear Information System (INIS)

Harkleroad, J.R.

1983-01-01

A synopsis of the March 22, 1975 fire at Browns Ferry Nuclear Plant is discussed. Emphasis is placed on events prior to and during the fire. How the fire started, fire fighting activities, fire and smoke development, and restoration activities are discussed

Unusual Slowly Rotating Brown Dwarfs Discovered through Precision Spitzer Photometry

Science.gov (United States)

Heinze, Aren; Metchev, S.

2014-01-01

Many brown dwarfs exhibit low-amplitude rotationally modulated variability due to photospheric inhomogeneities caused by condensate clouds in their atmospheres. The Spitzer Space Telescope 'Weather on Other Worlds' (WoW) project has monitored 44 brown dwarfs at unprecedented photometric precision from space. We present one of several important new results from WoW: the discovery of brown dwarfs with unexpectedly slow rotation periods. While most brown dwarfs have periods of 2-12 hours, we have identified two with well-constrained periods of 13±1 and >20 hours, respectively, and 2 others that show more tentative evidence of longer than 20-hour periods. By serving as almost non-rotating standards, these objects will allow more accurate calibration of spectroscopic measurements of brown dwarfs' projected rotational velocities. The existence of such slowly-rotating objects also constrains models of brown dwarf formation and angular momentum evolution.

Platform construction of molecular breeding for utilization of brown macroalgae.

Science.gov (United States)

Takagi, Toshiyuki; Kuroda, Kouichi; Ueda, Mitsuyoshi

2018-01-01

Brown macroalgae are characterized by a large size and high productivity without requiring arable land, fresh water, and fertilizer. Furthermore, since brown macroalgae contain little or no lignin, simple biorefinery processing can efficiently produce sugars from this material. Therefore, brown macroalgae have attracted attention as an alternative feedstock for bioethanol production. However, the utilization of biotechnologies previously developed for terrestrial biomass processing results in difficulties in the bioconversion of brown macroalgae. Recently, several studies have developed biotechnologies for using major carbohydrates of brown macroalgae, such as laminarin, mannitol, and alginate. This review focuses on these fermentation biotechnologies using natural or engineered microorganisms. Copyright © 2017 The Society for Biotechnology, Japan. Published by Elsevier B.V. All rights reserved.

How Glassy States Affect Brown Carbon Production?

Science.gov (United States)

Liu, P.; Li, Y.; Wang, Y.; Bateman, A. P.; Zhang, Y.; Gong, Z.; Gilles, M. K.; Martin, S. T.

2015-12-01

Secondary organic material (SOM) can become light-absorbing (i.e. brown carbon) via multiphase reactions with nitrogen-containing species such as ammonia and amines. The physical states of SOM, however, potentially slow the diffusion of reactant molecules in organic matrix under conditions that semisolids or solids prevail, thus inhibiting the browning reaction pathways. In this study, the physical states and the in-particle diffusivity were investigated by measuring the evaporation kinetics of both water and organics from aromatic-derived SOMs using a quartz-crystal-microbalance (QCM). The results indicate that the SOMs derived from aromatic precursors toluene and m-xylene became solid (glassy) and the in particle diffusion was significantly impeded for sufficiently low relative humidity ( toluene-derived SOM after ammonia exposure at varied RHs. The results suggest that the production of light-absorbing nitrogen-containing compounds from multiphase reactions with ammonia was kinetically limited in the glassy organic matrix, which otherwise produce brown carbon. The results of this study have significant implications for production and optical properties of brown carbon in urban atmospheres that ultimately influence the climate and tropospheric photochemistry.

Movement and mortality of stocked brown trout in a stream

DEFF Research Database (Denmark)

Aarestrup, Kim; Jepsen, Niels; Koed, Anders

2005-01-01

The movement and mortality of stocked brown trout Salmo trutta were investigated using radio telemetry. Four brown trout left the study area whereas the remaining fish were stationary. After 5 weeks, 13 out of 50 tagged brown trout were still alive in the stream. Surviving fish had a significantly...

Restricting glycolysis impairs brown adipocyte glucose and oxygen consumption

DEFF Research Database (Denmark)

Winther, Sally; Isidor, Marie Sophie; Basse, Astrid Linde

2018-01-01

During thermogenic activation, brown adipocytes take up large amounts of glucose. In addition, cold stimulation leads to an upregulation of glycolytic enzymes. Here we have investigated the importance of glycolysis for brown adipocyte glucose consumption and thermogenesis. Using siRNA-mediated kn......During thermogenic activation, brown adipocytes take up large amounts of glucose. In addition, cold stimulation leads to an upregulation of glycolytic enzymes. Here we have investigated the importance of glycolysis for brown adipocyte glucose consumption and thermogenesis. Using si...... of glycolysis, i.e., hexokinase 2 (HK2) and pyruvate kinase M (PKM), respectively, decreased glucose uptake and ISO-stimulated oxygen consumption. HK2 knockdown had a more severe effect, which, in contrast to PKM knockdown, could not be rescued by supplementation with pyruvate. Hence, brown adipocytes rely...... on glucose consumption and glycolytic flux to achieve maximum thermogenic output, with glycolysis likely supporting thermogenesis not only by pyruvate formation but also by supplying intermediates for efferent metabolic pathways....

Browns Ferry charcoal adsorber incident

International Nuclear Information System (INIS)

Mays, G.T.

1979-01-01

The article reviews the temperature excursion in the charcoal adsorber beds of the Browns Ferry Unit 3 off-gas system that occurred on July 17, 1977. Significant temperature increases were experienced in the charcoal adsorber beds when charcoal fines were ignited by the ignition of a combustible mixture of hydrogen and oxygen in the off-gas system. The Browns Ferry off-gas system is described, and events leading up to and surrounding the incident are discussed. The follow-up investigation by Tennessee Valley Authority and General Electric Company personnel and their recommendations for system and operational modifications are summarized

Microlensing Binaries with Candidate Brown Dwarf Companions

DEFF Research Database (Denmark)

Shin, I.-G; Han, C.; Gould, A.

2012-01-01

masses of the brown dwarf companions are 0.02 ± 0.01 M⊙ and 0.019 ± 0.002 M⊙ for MOA-2011-BLG-104/OGLE-2011-BLG-0172 and MOA-2011-BLG-149, respectively, and both companions are orbiting low-mass M dwarf host stars. More microlensing brown dwarfs are expected to be detected as the number of lensing events...

Development of brown coal mining in the Federal Republic of Germany

Energy Technology Data Exchange (ETDEWEB)

Tilmann, W

1985-01-01

The significance of brown coal mining in the Federal Republic of Germany for the development of opencast technology and the power industry is discussed with emphasis on mining in the Rhineland Area. In 1984, 126.7 mt of brown coal were produced in the Federal Republic of Germany. In the development of high-performance equipment it is essential that the efficiency of the bucket-wheel excavator is increased. Trains and conveyors are mainly used for mine transport in the Federal Republic of Germany. A high moral commitment is linked to land claims, recultivation and environmental issues on the part of brown coal mining. In 1984 the percentage share of brown coal supplied to the public power stations was 83.6%, corresponding to 105.9 mt. The installed capacity of all brown coal power stations amounted to 12,764 MW at the end of 1984, providing around one quarter of overall public power output. Charge coal for coal refining has become more important and the production of brown coal dust and brown coal coke has also increased. The share of brown coal in domestic primary energy production is currently around 24% of 151 mt hard-coal units or around 10% of 376.5 mt hard-coal units in terms of energy consumption. 12 references.

The emergence of cold-induced brown adipocytes in mouse white fat depots is determined predominantly by white to brown adipocyte transdifferentiation

DEFF Research Database (Denmark)

Barbatelli, G.; Murano, I.; Madsen, Lise

2010-01-01

The origin of brown adipocytes arising in white adipose tissue (WAT) after cold acclimatization is unclear. Here, we demonstrate that several UCP1-immunoreactive brown adipocytes occurring in WAT after cold acclimatization have a mixed morphology (paucilocular adipocytes). These cells also had a ...

Explaining millimeter-sized particles in brown dwarf disks

NARCIS (Netherlands)

Pinilla, P.; Birnstiel, T.; Benisty, M.; Ricci, L.; Natta, A.; Dullemond, C.P.; Dominik, C.; Testi, L.

2013-01-01

Context. Planets have been detected around a variety of stars, including low-mass objects, such as brown dwarfs. However, such extreme cases are challenging for planet formation models. Recent sub-millimeter observations of disks around brown dwarf measured low spectral indices of the continuum

CASE REPORT PET/CT-positive brown tumour – a potentially ...

African Journals Online (AJOL)

Brown tumor of bone: a potential source of false-positive Thallium-201 localization. J Nucl Med 1989; 30: 1264-1267. 4. Nassar GM, Ayus JC. Images in clinical medicine. Brown tumor in end stage renal disease. N Engl J Med. 1999; 341: 1652. 5. Keyser JS, Postma GN. Brown tumor of the mandible. Am J Otolaryngol 1996; ...

After Brown U.'s Report on Slavery, Silence (So Far)

Science.gov (United States)

Bartlett, Thomas

2006-01-01

This article, discusses Brown University's slavery report, a 106-page narrative examination of the early connections between Brown University and slavery, that has been greeted--so far--with silence. The report, done at the behest of Ruth J. Simmons, Brown's president and herself a descendant of slaves, is an unsparing look at a shameful side of…

The membrane may be an important factor in browning of fresh-cut pear.

Science.gov (United States)

Li, Zhenghong; Zhang, Yuxing; Ge, Huibo

2017-09-01

Surface browning is an important cause of deterioration of fresh-cut fruit during postharvest handling. In this paper, four pear cultivars with different extents of natural browning were selected to analyse the factors involved in browning. The main results are as follows: the lipoxygenase (LOX) activity of 'Mantianhong' and 'Yali' pears was higher accompanied by a stronger degree of browning, while the LOX activity in 'Xueqing' and 'Xinli 7' pears was lower, with less browning. A higher unsaturated fatty acid ratio of pear resulted in reduced browning. The cell membranes disappeared 30min after being cut in 'Mantianhong' pear, which browns easily; however, the cell membranes were still intact 30min after being cut in 'Xueqing' pear, which does not brown easily. Therefore, it can be assumed that the stability of the cell membrane plays an important role in inhibiting browning of fresh-cut pears. Copyright © 2017. Published by Elsevier Ltd.

Browning and graying: novel transcriptional regulators of brown and beige fat tissues and aging

Directory of Open Access Journals (Sweden)

Elisabetta eMueller

2016-03-01

Full Text Available Obesity represents a major risk factor for the development of a number of metabolic disorders, including cardiovascular disease and type 2 diabetes. Since the discovery that brown and beige fat cells exist in adult humans and contribute to energy expenditure, increasing interest has been devoted to the understanding of the molecular switches turning on calorie utilization. It has been reported that the ability of thermogenic tissues to burn energy declines during aging, possibly contributing to the development of metabolic dysfunction late in life. This review will focus on the recently identified transcriptional modulators of brown and beige cells and will discuss the potential impact of some of these thermogenic factors on age-associated metabolic disorders.

Phospholipids of New Zealand Edible Brown Algae.

Science.gov (United States)

Vyssotski, Mikhail; Lagutin, Kirill; MacKenzie, Andrew; Mitchell, Kevin; Scott, Dawn

2017-07-01

Edible brown algae have attracted interest as a source of beneficial allenic carotenoid fucoxanthin, and glyco- and phospholipids enriched in polyunsaturated fatty acids. Unlike green algae, brown algae contain no or little phosphatidylserine, possessing an unusual aminophospholipid, phosphatidyl-O-[N-(2-hydroxyethyl) glycine], PHEG, instead. When our routinely used technique of 31 P-NMR analysis of phospholipids was applied to the samples of edible New Zealand brown algae, a number of signals corresponding to unidentified phosphorus-containing compounds were observed in total lipids. NI (negative ion) ESI QToF MS spectra confirmed the presence of more familiar phospholipids, and also suggested the presence of PHEG or its isomers. The structure of PHEG was confirmed by comparison with a synthetic standard. An unusual MS fragmentation pattern that was also observed prompted us to synthesise a number of possible candidates, and was found to follow that of phosphatidylhydroxyethyl methylcarbamate, likely an extraction artefact. An unexpected outcome was the finding of ceramidephosphoinositol that has not been reported previously as occurring in brown algae. An uncommon arsenic-containing phospholipid has also been observed and quantified, and its TLC behaviour studied, along with that of the newly synthesised lipids.

Investigation of metal ions sorption of brown peat moss powder

Science.gov (United States)

Kelus, Nadezhda; Blokhina, Elena; Novikov, Dmitry; Novikova, Yaroslavna; Chuchalin, Vladimir

2017-11-01

For regularities research of sorptive extraction of heavy metal ions by cellulose and its derivates from aquatic solution of electrolytes it is necessary to find possible mechanism of sorption process and to choice a model describing this process. The present article investigates the regularities of aliovalent metals sorption on brown peat moss powder. The results show that sorption isotherm of Al3+ ions is described by Freundlich isotherm and sorption isotherms of Na+ i Ni2+ are described by Langmuir isotherm. To identify the mechanisms of brown peat moss powder sorption the IR-spectra of the initial brown peat moss powder samples and brown peat moss powder samples after Ni (II) sorption were studied. Metal ion binding mechanisms by brown peat moss powder points to ion exchange, physical adsorption, and complex formation with hydroxyl and carboxyl groups.

Pengaruh cendawan endofit terhadap biologi dan statistik demografi wereng batang cokelat Nilaparvata lugens Stál (Hemiptera: Delphacidae

Directory of Open Access Journals (Sweden)

Amanda Mawan

2015-09-01

Full Text Available Endophytic fungi is an endosymbiont that lives within host plant tissues and does not necessary cause any harm to plants. This type of fungus are important as mediators in plant-herbivore interactions. One of the endophytic fungi in rice is Nigrospora sp. The effects of Nigrospora sp. on the biology and demographic statistic of Nilaparvata lugens Stál (Hemiptera: Delphacidae were studied in the laboratory. We used Nigrospora sp. culture powder was used to inoculate the fungi to rice seeds by mixing 10 g of flour endophytic per 1 kg rice seeds. The mixture was then stored in damp and dark storage. Results showed that the rice seeds treated with endophytic fungi showed some resistance to N. lugens. Eggs and early stages of nymph mortality was increased, higher than the control. Endophytic fungi also affect the nymphs growth rates by slowing it down, prolonging N. lugens life cycle, preoviposition period as well as delayed the age at first reproduction. N. lugens population growth is effected by Nigrospora sp. in laboratory scale. Thus, it has the potential as an alternative way to control N. lugens population. In addition, inoculation of endophytic fungi could be a useful method for protecting rice plants from N. lugens.

NFIA co-localizes with PPARγ and transcriptionally controls the brown fat gene program

DEFF Research Database (Denmark)

Hiraike, Yuta; Waki, Hironori; Yu, Jing

2017-01-01

. NFIA and the master transcriptional regulator of adipogenesis, PPARγ, co-localize at the brown-fat-specific enhancers. Moreover, the binding of NFIA precedes and facilitates the binding of PPARγ, leading to increased chromatin accessibility and active transcription. Introduction of NFIA into myoblasts...... results in brown adipocyte differentiation. Conversely, the brown fat of NFIA-knockout mice displays impaired expression of the brown-fat-specific genes and reciprocal elevation of muscle genes. Finally, expression of NFIA and the brown-fat-specific genes is positively correlated in human brown fat...

Inhibition of Enzymatic Browning of Chlorogenic Acid by Sulfur-Containing Compounds

NARCIS (Netherlands)

Kuijpers, T.F.M.; Narvaez Cuenca, C.E.; Vincken, J.P.; Verloop, J.W.; Berkel, van W.J.H.; Gruppen, H.

2012-01-01

The antibrowning activity of sodium hydrogen sulfite (NaHSO3) was compared to that of other sulfur-containing compounds. Inhibition of enzymatic browning was investigated using a model browning system consisting of mushroom tyrosinase and chlorogenic acid (5-CQA). Development of brown color

Maxillary brown tumor as initial presentation of parathyroid adenoma: A case report

Directory of Open Access Journals (Sweden)

Hon-Ke Sia

2012-07-01

Full Text Available Brown tumor is a rare late-stage skeletal change caused by long-term stimulation of excess parathyroid hormone. It is not neoplastic, but a reparative cellular process. Common sites of brown tumor are the ribs, clavicle, long bones and pelvic girdle. Solitary maxillary brown tumor as initial presentation of primary hyperparathyroidism is rare; it is often accompanied by brown tumors of the other facial bones. Here, we present the first case of solitary maxillary brown tumor in a 29-year-old ethnic Chinese woman with initial presentation of a large tumor filling the left maxillary sinus. Underlying long-standing primary hyperparathyroidism caused by a large parathyroid adenoma was finally diagnosed. Brown tumor tends to be misdiagnosed as malignancy, and delayed diagnosis of the underlying hyperparathyroidism is common. Our case validates the suggestion that young women have a higher probability of brown tumor. Biopsy of the suspicious bone tumor and blood tests for calcium and parathyroid hormone level are crucial and essential to reach the correct diagnosis. Most brown tumors show spontaneous regression after parathyroidectomy. However, direct excision of the brown tumor may be indicated to avoid the risk of facial deformity and orbital compression at a special anatomical site, as in our case.

Obituary: Beth Brown (1969-2008)

Science.gov (United States)

Bregman, Joel

2011-12-01

The astronomical community lost one of its most buoyant and caring individuals when Beth Brown died, unexpectedly, at the age of 39 from a pulmonary embolism. Beth Brown was born in Roanoke, Virginia where she developed a deep interest in astronomy, science, and science fiction (Star Trek). After graduating as the valedictorian of William Fleming High School's Class of 1987, she attended Howard University, where she graduated summa cum laude in 1991 with a bachelor's degree in astrophysics. Following a year in the graduate physics program at Howard, she entered the graduate program in the Department of Astronomy at the University of Michigan, the first African-American woman in the program. She received her PhD in 1998, working with X-ray observations of elliptical galaxies from the Röntgen Satellite (ROSAT; Joel Bregman was her advisor). She compiled and analyzed the first large complete sample of such galaxies with ROSAT and her papers in this area made an impact in the field. Following her PhD, Beth Brown held a National Academy of Science & National Research Council Postdoctoral Research Fellowship at NASA's Goddard Space Flight Center. Subsequently, she became a civil servant at the National Space Science Data Center at GSFC, where she was involved in data archival activities as well as education and outreach, a continuing passion in her life. In 2006, Brown became an Astrophysics Fellow at GSFC, during which time she worked as a visiting Assistant Professor at Howard University, where she taught and worked with students and faculty to improve the teaching observatory. At the time of her death, she was eagerly looking forward to a new position at GSFC as the Assistant Director for Science Communications and Higher Education. Beth Brown was a joyous individual who loved to work with people, especially in educating them about our remarkable field. Her warmth and openness was a great aid in making accessible explanations of otherwise daunting astrophysical

Optical visualisation of thermogenesis in stimulated single-cell brown adipocytes.

Science.gov (United States)

Kriszt, Rókus; Arai, Satoshi; Itoh, Hideki; Lee, Michelle H; Goralczyk, Anna G; Ang, Xiu Min; Cypess, Aaron M; White, Andrew P; Shamsi, Farnaz; Xue, Ruidan; Lee, Jung Yeol; Lee, Sung-Chan; Hou, Yanyan; Kitaguchi, Tetsuya; Sudhaharan, Thankiah; Ishiwata, Shin'ichi; Lane, E Birgitte; Chang, Young-Tae; Tseng, Yu-Hua; Suzuki, Madoka; Raghunath, Michael

2017-05-03

The identification of brown adipose deposits in adults has led to significant interest in targeting this metabolically active tissue for treatment of obesity and diabetes. Improved methods for the direct measurement of heat production as the signature function of brown adipocytes (BAs), particularly at the single cell level, would be of substantial benefit to these ongoing efforts. Here, we report the first application of a small molecule-type thermosensitive fluorescent dye, ERthermAC, to monitor thermogenesis in BAs derived from murine brown fat precursors and in human brown fat cells differentiated from human neck brown preadipocytes. ERthermAC accumulated in the endoplasmic reticulum of BAs and displayed a marked change in fluorescence intensity in response to adrenergic stimulation of cells, which corresponded to temperature change. ERthermAC fluorescence intensity profiles were congruent with mitochondrial depolarisation events visualised by the JC-1 probe. Moreover, the averaged fluorescence intensity changes across a population of cells correlated well with dynamic changes such as thermal power, oxygen consumption, and extracellular acidification rates. These findings suggest ERthermAC as a promising new tool for studying thermogenic function in brown adipocytes of both murine and human origins.

Molecular Selectivity of Brown Carbon Chromophores

Energy Technology Data Exchange (ETDEWEB)

Laskin, Julia; Laskin, Alexander; Nizkorodov, Sergey; Roach, Patrick J.; Eckert, Peter A.; Gilles, Mary K.; Wang, Bingbing; Lee, Hyun Ji; Hu, Qichi

2014-10-21

Complementary methods of high-resolution mass spectrometry and micro-spectroscopy were utilized for molecular analysis of secondary organic aerosol (SOA) generated from ozonolysis of two structural monoterpene isomers: D-limonene (LSOA) and a-pinene (PSOA). Laboratory simulated aging of LSOA and PSOA, through conversion of carbonyls into imines mediated by NH3 vapors in humid air, resulted in selective browning of the LSOA sample, while the PSOA sample remained white. Comparative analysis of the reaction products in the aged LSOA and PSOA samples provided insights into chemistry relevant to formation of brown carbon chromophores. A significant fraction of carbonyl-imine conversion products with identical molecular formulas were detected in both samples. This reflects the high level of similarity in the molecular composition of these two closely related SOA materials. Several highly conjugated products were detected exclusively in the brown LSOA sample and were identified as potential chromophores responsible for the observed color change. The majority of the unique products in the aged LSOA sample with the highest number of double bonds contain two nitrogen atoms. We conclude that chromophores characteristic of the carbonyl- imine chemistry in LSOA are highly conjugated oligomers of secondary imines (Schiff bases) present at relatively low concentrations. Formation of this type of conjugated compounds in PSOA is hindered by the structural rigidity of the a-pinene oxidation products. Our results suggest that the overall light-absorbing properties of SOA may be determined by trace amounts of strong brown carbon chromophores.

Briquetting of Coke-Brown Coal Mixture

Directory of Open Access Journals (Sweden)

Ïurove Juraj

1998-09-01

Full Text Available The paper presents the results of the research of briquetting a coke-brown coal composite The operation consists of the feeding crushed coal and coke to moulds and pressing into briquettes which have been made in the Laboratories at the Mining Faculty of Technical University of Košice (Slovakia. In this research, all demands will be analyzed including the different aspects of the mechanical quality of briquettes, the proportion of fine pulverulent coal and coke in bricks, the requirements for briquetting the coke-brown coal materials.

Top-of-atmosphere radiative forcing affected by brown carbon in the upper troposphere

Science.gov (United States)

Zhang, Yuzhong; Forrister, Haviland; Liu, Jiumeng; Dibb, Jack; Anderson, Bruce; Schwarz, Joshua P.; Perring, Anne E.; Jimenez, Jose L.; Campuzano-Jost, Pedro; Wang, Yuhang; Nenes, Athanasios; Weber, Rodney J.

2017-07-01

Carbonaceous aerosols affect the global radiative balance by absorbing and scattering radiation, which leads to warming or cooling of the atmosphere, respectively. Black carbon is the main light-absorbing component. A portion of the organic aerosol known as brown carbon also absorbs light. The climate sensitivity to absorbing aerosols rapidly increases with altitude, but brown carbon measurements are limited in the upper troposphere. Here we present aircraft observations of vertical aerosol distributions over the continental United States in May and June 2012 to show that light-absorbing brown carbon is prevalent in the troposphere, and absorbs more short-wavelength radiation than black carbon at altitudes between 5 and 12 km. We find that brown carbon is transported to these altitudes by deep convection, and that in-cloud heterogeneous processing may produce brown carbon. Radiative transfer calculations suggest that brown carbon accounts for about 24% of combined black and brown carbon warming effect at the tropopause. Roughly two-thirds of the estimated brown carbon forcing occurs above 5 km, although most brown carbon is found below 5 km. The highest radiative absorption occurred during an event that ingested a wildfire plume. We conclude that high-altitude brown carbon from biomass burning is an unappreciated component of climate forcing.

Effects of White Rice, Brown Rice and Germinated Brown Rice on Antioxidant Status of Type 2 Diabetic Rats

OpenAIRE

Imam, Mustapha Umar; Musa, Siti Nor Asma; Azmi, Nur Hanisah; Ismail, Maznah

2012-01-01

Oxidative stress is implicated in the pathogenesis of diabetic complications, and can be increased by diet like white rice (WR). Though brown rice (BR) and germinated brown rice (GBR) have high antioxidant potentials as a result of their bioactive compounds, reports of their effects on oxidative stress-related conditions such as type 2 diabetes are lacking. We hypothesized therefore that if BR and GBR were to improve antioxidant status, they would be better for rice consuming populations inst...

MEASURING TINY MASS ACCRETION RATES ONTO YOUNG BROWN DWARFS

International Nuclear Information System (INIS)

Herczeg, Gregory J.; Cruz, Kelle L.; Hillenbrand, Lynne A.

2009-01-01

We present low-resolution Keck I/LRIS spectra spanning from 3200 to 9000 A of nine young brown dwarfs and three low-mass stars in the TW Hya Association and in Upper Sco. The optical spectral types of the brown dwarfs range from M5.5 to M8.75, though two have near-IR spectral types of early L dwarfs. We report new accretion rates derived from excess Balmer continuum emission for the low-mass stars TW Hya and Hen 3-600A and the brown dwarfs 2MASS J12073347-3932540, UScoCTIO 128, SSSPM J1102-3431, USco J160606.29-233513.3, DENIS-P J160603.9-205644, and Oph J162225-240515B, and upper limits on accretion for the low-mass star Hen 3-600B and the brown dwarfs UScoCTIO 112, Oph J162225-240515A, and USco J160723.82-221102.0. For the six brown dwarfs in our sample that are faintest at short wavelengths, the accretion luminosity or upper limit is measurable only when the image is binned over large wavelength intervals. This method extends our sensitivity to accretion rate down to ∼10 -13 M sun yr -1 for brown dwarfs. Since the ability to measure an accretion rate from excess Balmer continuum emission depends on the contrast between excess continuum emission and the underlying photosphere, for objects with earlier spectral types the upper limit on accretion rate is much higher. Absolute uncertainties in our accretion rate measurements of ∼3-5 include uncertainty in accretion models, brown dwarf masses, and distance. The accretion rate of 2 x 10 -12 M sun yr -1 onto 2MASS J12073347-3932540 is within 15% of two previous measurements, despite large changes in the Hα flux.

A Panchromatic View of Brown Dwarf Aurorae

Energy Technology Data Exchange (ETDEWEB)

Pineda, J. Sebastian [University of Colorado Boulder, Laboratory for Atmospheric and Space Physics, 3665 Discovery Drive, Boulder CO, 80303 (United States); Hallinan, Gregg; Kao, Melodie M. [California Institute of Technology, Department of Astronomy, 1200 E. California Avenue, Pasadena CA, 91125 (United States)

2017-09-01

Stellar coronal activity has been shown to persist into the low-mass star regime, down to late M-dwarf spectral types. However, there is now an accumulation of evidence suggesting that at the end of the main sequence, there is a transition in the nature of the magnetic activity from chromospheric and coronal to planet-like and auroral, from local impulsive heating via flares and MHD wave dissipation to energy dissipation from strong large-scale magnetospheric current systems. We examine this transition and the prevalence of auroral activity in brown dwarfs through a compilation of multiwavelength surveys of magnetic activity, including radio, X-ray, and optical. We compile the results of those surveys and place their conclusions in the context of auroral emission as a consequence of large-scale magnetospheric current systems that accelerate energetic electron beams and drive the particles to impact the cool atmospheric gas. We explore the different manifestations of auroral phenomena, like H α , in brown dwarf atmospheres and define their distinguishing characteristics. We conclude that large-amplitude photometric variability in the near-infrared is most likely a consequence of clouds in brown dwarf atmospheres, but that auroral activity may be responsible for long-lived stable surface features. We report a connection between auroral H α emission and quiescent radio emission in electron cyclotron maser instability pulsing brown dwarfs, suggesting a potential underlying physical connection between quiescent and auroral emissions. We also discuss the electrodynamic engines powering brown dwarf aurorae and the possible role of satellites around these systems both to power the aurorae and seed the magnetosphere with plasma.

Reduction of Exudates (Browning) in Sugarcane Micro Propagation ...

African Journals Online (AJOL)

... of this variety, ascorbic acid and citric acid was added as constituent of the media using MS and stock at different concentrations. The browning was reduced drastically at the addition of 0.1g/litre ascorbic acid and 0.15g/litre citric acid. Keywords: reduction, exudates browning, micro propagation, sugarcane. Nig J. Biotech.

Direct Evidence of Brown Adipocytes in Different Fat Depots in Children

Science.gov (United States)

Rockstroh, Denise; Landgraf, Kathrin; Wagner, Isabel Viola; Gesing, Julia; Tauscher, Roy; Lakowa, Nicole; Kiess, Wieland; Bühligen, Ulf; Wojan, Magdalena; Till, Holger; Blüher, Matthias; Körner, Antje

2015-01-01

Recent studies suggested the persistence of brown adipocytes in adult humans, as opposed to being exclusively present in infancy. In this study, we investigated the presence of brown-like adipocytes in adipose tissue (AT) samples of children and adolescents aged 0 to 18 years and evaluated the association with age, location, and obesity. For this, we analysed AT samples from 131 children and 23 adults by histological, immunohistochemical and expression analyses. We detected brown-like and UCP1 positive adipocytes in 10.3% of 87 lean children (aged 0.3 to 10.7 years) and in one overweight infant, whereas we did not find brown adipocytes in obese children or adults. In our samples, the brown-like adipocytes were interspersed within white AT of perirenal, visceral and also subcutaneous depots. Samples with brown-like adipocytes showed an increased expression of UCP1 (>200fold), PRDM16 (2.8fold), PGC1α and CIDEA while other brown/beige selective markers, such as PAT2, P2RX5, ZIC1, LHX8, TMEM26, HOXC9 and TBX1 were not significantly different between UCP1 positive and negative samples. We identified a positive correlation between UCP1 and PRDM16 within UCP1 positive samples, but not with any other brown/beige marker. In addition, we observed significantly increased PRDM16 and PAT2 expression in subcutaneous and visceral AT samples with high UCP1 expression in adults. Our data indicate that brown-like adipocytes are present well beyond infancy in subcutaneous depots of non-obese children. The presence was not restricted to typical perirenal locations, but they were also interspersed within WAT of visceral and subcutaneous depots. PMID:25706927

Regulation of glycolysis in brown adipocytes by HIF-1α

DEFF Research Database (Denmark)

Basse, Astrid L; Isidor, Marie S; Winther, Sally

2017-01-01

Brown adipose tissue takes up large amounts of glucose during cold exposure in mice and humans. Here we report an induction of glucose transporter 1 expression and increased expression of several glycolytic enzymes in brown adipose tissue from cold-exposed mice. Accordingly, these genes were also...... with glucose as the only exogenously added fuel. These data suggest that HIF-1α-dependent regulation of glycolysis is necessary for maximum glucose metabolism in brown adipocytes....

New Brown Dwarf Discs in Upper Scorpius Observed with WISE

Science.gov (United States)

Dawson, P.; Scholz, A.; Ray, T. P.; Natta, A.; Marsh, K. A.; Padgett, D.; Ressler, M. E.

2013-01-01

We present a census of the disc population for UKIDSS selected brown dwarfs in the 5-10 Myr old Upper Scorpius OB association. For 116 objects originally identified in UKIDSS, the majority of them not studied in previous publications, we obtain photometry from the Wide-Field Infrared Survey Explorer data base. The resulting colour magnitude and colour colour plots clearly show two separate populations of objects, interpreted as brown dwarfs with discs (class II) and without discs (class III). We identify 27 class II brown dwarfs, 14 of them not previously known. This disc fraction (27 out of 116, or 23%) among brown dwarfs was found to be similar to results for K/M stars in Upper Scorpius, suggesting that the lifetimes of discs are independent of the mass of the central object for low-mass stars and brown dwarfs. 5 out of 27 discs (19 per cent) lack excess at 3.4 and 4.6 microns and are potential transition discs (i.e. are in transition from class II to class III). The transition disc fraction is comparable to low-mass stars.We estimate that the time-scale for a typical transition from class II to class III is less than 0.4 Myr for brown dwarfs. These results suggest that the evolution of brown dwarf discs mirrors the behaviour of discs around low-mass stars, with disc lifetimes of the order of 5 10 Myr and a disc clearing time-scale significantly shorter than 1 Myr.

Cellular origins of cold-induced brown adipocytes in adult mice.

Science.gov (United States)

Lee, Yun-Hee; Petkova, Anelia P; Konkar, Anish A; Granneman, James G

2015-01-01

This work investigated how cold stress induces the appearance of brown adipocytes (BAs) in brown and white adipose tissues (WATs) of adult mice. In interscapular brown adipose tissue (iBAT), cold exposure increased proliferation of endothelial cells and interstitial cells expressing platelet-derived growth factor receptor, α polypeptide (PDGFRα) by 3- to 4-fold. Surprisingly, brown adipogenesis and angiogenesis were largely restricted to the dorsal edge of iBAT. Although cold stress did not increase proliferation in inguinal white adipose tissue (ingWAT), the percentage of BAs, defined as multilocular adipocytes that express uncoupling protein 1, rose from undetectable to 30% of total adipocytes. To trace the origins of cold-induced BAs, we genetically tagged PDGFRα(+) cells and adipocytes prior to cold exposure, using Pdgfra-Cre recombinase estrogen receptor T2 fusion protein (CreER(T2)) and adiponectin-CreER(T2), respectively. In iBAT, cold stress triggered the proliferation and differentiation of PDGFRα(+) cells into BAs. In contrast, all newly observed BAs in ingWAT (5207 out of 5207) were derived from unilocular adipocytes tagged by adiponectin-CreER(T2)-mediated recombination. Surgical denervation of iBAT reduced cold-induced brown adipogenesis by >85%, whereas infusion of norepinephrine (NE) mimicked the effects of cold in warm-adapted mice. NE-induced de novo brown adipogenesis in iBAT was eliminated in mice lacking β1-adrenergic receptors. These observations identify a novel tissue niche for brown adipogenesis in iBAT and further define depot-specific mechanisms of BA recruitment. © FASEB.

The "brown" environmental agenda and the constitutional duties of ...

African Journals Online (AJOL)

This note explores the interrelationship between ecologically sustainable development (the green environmental agenda) and pro-poor urban development and environmental health (the brown environmental agenda) in relation to local government in South Africa. The meaning and relevance of the brown agenda versus ...

Interactive Effects of Southern Rice Black-Streaked Dwarf Virus Infection of Host Plant and Vector on Performance of the Vector, Sogatella furcifera (Homoptera: Delphacidae).

Science.gov (United States)

Lei, Wenbin; Liu, Danfeng; Li, Pei; Hou, Maolin

2014-10-01

Performance of insect vectors can be influenced by the viruses they transmit, either directly by infection of the vectors or indirectly via infection of the host plants. Southern rice black-streaked dwarf virus (SRBSDV) is a propagative virus transmitted by the white-backed planthopper, Sogatella furcifera (Hovath). To elucidate the influence of SRBSDV on the performance of white-backed planthopper, life parameters of viruliferous and nonviruliferous white-backed planthopper fed rice seedlings infected or noninfected with SRBSDV were measured using a factorial design. Regardless of the infection status of the rice plant host, viruliferous white-backed planthopper nymphs took longer to develop from nymph to adult than did nonviruliferous nymphs. Viruliferous white-backed planthopper females deposited fewer eggs than nonviruliferous females and both viruliferous and nonviruliferous white-backed planthopper females laid fewer eggs on infected than on noninfected plants. Longevity of white-backed planthopper females was also affected by the infection status of the rice plant and white-backed planthopper. Nonviruliferous white-backed planthopper females that fed on infected rice plants lived longer than the other three treatment groups. These results indicate that the performance of white-backed planthopper is affected by SRBSDV either directly (by infection of white-backed planthopper) or indirectly (by infection of rice plant). The extended development of viruliferous nymphs and the prolonged life span of nonviruliferous adults on infected plants may increase their likelihood of transmitting virus, which would increase virus spread. © 2014 Entomological Society of America.

Black, White, and Brown: The Transformation of Public Education in America

Science.gov (United States)

Willie, Charles Vert; Willie, Sarah Susannah

2005-01-01

This article reflects upon changes in U.S. education since the U.S. Supreme Court's 1954 decision in Brown v. the Board of Education of Topeka, Kansas. The authors reject both the naively hopeful and the bitterly cynical interpretations of the efficacy of Brown in favor of a more moderate assessment: Brown has had many positive effects, they…

Molecular cloning and expression profile of an ATP-binding cassette (ABC) transporter gene from the hemipteran insect Nilaparvata lugens.

Science.gov (United States)

Zha, W J; Li, S H; Zhou, L; Chen, Z J; Liu, K; Yang, G C; Hu, G; He, G C; You, A Q

2015-03-30

The ATP-binding cassette (ABC) transporters belong to a large superfamily of proteins that have important physiological functions in all living organisms. In insects, ABC transporters have important functions in the transport of molecules, and are also involved in insecticide resistance, metabolism, and development. In this study, the Nilaparvata lugens Stal (Hemiptera: Delphacidae) ABCG (NlABCG) gene was identified and characterized. The complete mRNA sequence of NlABCG was 2608-bp long, with an open reading frame of 2064 bp encoding a protein comprised of 687 amino acids. The conserved regions include three N-glycosylation and 34 phosphorylation sites, as well as seven transmembrane domains. The amino acid identity with the closely related species Acyrthosiphon pisum was 42.8%. Developmental expression analysis using quantitative real-time reverse transcriptase PCR suggested that the NlABCG transcript was expressed at all developmental stages of N. lugens. The lowest expression of NlABCG was in the 1st instar, and levels increased with larval growth. The transcript profiles of NlABCG were analyzed in various tissues from a 5th instar nymph, and the highest expression was observed in the midgut. These results suggest that the sequence, characteristics, and expression of NlABCG are highly conserved, and basic information is provided for its functional analysis.

What happened to the Kuo-Brown interaction?

International Nuclear Information System (INIS)

Osnes, E.

1987-01-01

Twenty years of efforts to calculate the shell-model effective interaction, starting from the free nucleon-nucleon (NN) interaction and using many-body perturbation theory, are briefly reviewed. A description is given of the pioneering work of Kuo and Brown, in which the effective interaction was approximated by the Bethe-Brueckner-Goldstone G-matrix and the lowest order core-polarization correction. Subsequent developments which cast doubt upon the simple Kuo-Brown approximation are reviewed. Some of these problems have been shown to arise from inadequate treatment of various higher order contributions, whereas other problems are related to the strong tensor component of the NN interaction used. In fact, modern meson-exchange potentials have much weaker tensor forces and give rise to effective interactions which are similar to the original Kuo-Brown interaction. Applications of these new effective forces to shell-model calculations in the sd-shell are discussed

Brown dwarfs forming in discs: Where to look for them?

Directory of Open Access Journals (Sweden)

Stamatellos D.

2011-07-01

Full Text Available A large fraction of the observed brown dwarfs may form by gravitational fragmentation of unstable discs. This model reproduces the brown dwarf desert, and provides an explanation for the existence of planetary-mass objects and for the binary properties of low-mass objects. We have performed an ensemble of radiative hydrodynamic simulations and determined the statistical properties of the low-mass objects produced by gravitational fragmentation of discs. We suggest that there is a population of brown dwarfs loosely bound on wide orbits (100–5000 AU around Sun-like stars that surveys of brown dwarf companions should target. Our simulations also indicate that planetary-mass companions to Sun-like stars are unlikely to form by disc fragmentation.

Startup operation of Browns Ferry's 1152-MW nuclear units

International Nuclear Information System (INIS)

Calhoun, J.R.; Green, H.J.; Beers, R.B.

1975-01-01

An overview is presented of startup operation for the Browns Ferry-1 reactor, and comparisons are made with the startup of Browns Ferry-2. Included are comments on the selection of the BWR type steam supply system, reactor fueling, problems encountered, and plant availability

Phytase activity in brown rice during steeping and sprouting

NARCIS (Netherlands)

Ou, K.; Cheng, Y.; Xing, Y.; Lin, L.; Nout, M.J.R.; Liang, J.

2011-01-01

Phytase in brown rice will be activated and accumulated during seed germination. Changes of phytase activity in brown rice during two stages of germination (steeping and sprouting) affected by process conditions were studied. It was shown that steeping led to significant decrease of phytase activity

Being Black and Brown in the 21st Century

Directory of Open Access Journals (Sweden)

Pierre W. Orelus

2012-11-01

Full Text Available Depending on one’s level of understanding and awareness about the plight of Black and Brown people, one might argue that they are better off today than they were 50 years ago or so, especially when one remembers the Jim Crow era during which Black and Brown people were ruthlessly brutalized, particularly by White supremacist groups such as the Klu Klux Kan. However, if one critically analyzed the achievement gap between students of color and their White counterparts, the decline in incomes, and other forms of educational and socioeconomic inequality that Black and Brown people, particularly poor students of color, have been experiencing for the last several decades or so, one would realize that substantially nothing has changed for them. In light of this view, this article explores the educational and socioeconomic conditions of People of Color, including those of linguistically and culturally diverse students. Specifically, it examines the ways and the degree to which lack of resources combined with institutional racism and the legacy of slavery continue to limit the life chances of Black and Brown people in the 21st century. The author ends this article making recommendations to counter inequality in schools and society at large that Black and Brown people have been facing.

Description of the immature stages of the planthopper Lacertinella australis (Hemiptera: Delphacidae)

Science.gov (United States)

Batiz, M. F. Rossi; Marino de Remes Lenicov, A. M.; Hagedorn, Henry

2014-01-01

Abstract The five immature stages of the planthopper Lacertinella australis (Remes Lenicov and Rossi Batiz) (Hemiptera: Delphacidae: Saccharosydnini) are described and illustrated. The main characters that allowed us to distinguish the various stages were body size, number of tarsomeres and metatibial spines, and number of teeth on the spur. New biological data based on laboratory rearing and field observations showed that L. australis can carry out its biological cycle successfully on the graminaceous pampas grass ( Cortaderia spp. Stapf (Poales: Poaceae)). In addition, the efficient rearing in captivity, the high survivorship registered, and overwintering only on this host plant suggests that L. australis is a potential biocontrol agent of this invasive graminaceous weed. This study provides information about the immature stages , including a key for their identification, based on laboratory reared specimens and field observations. Resumen Se describen e ilustran las cinco etapas inmaduras de la especie de Saccharisydnini Lacertinella australis (Remes Lenicov and Rossi Batiz) (Hemiptera: Delphacidae). Los principales caracteres que permitieron distinguir las diferentes etapas fueron: tamaño corporal, número de espinas en los tarsómeros y metatibia y número de dientes en el espolón tibial. Nuevos datos biológicos, basados en la cría de laboratorio y observaciones de campo, mostraron que L. australis puede realizar su ciclo biológico exitosamente en la graminácea cortadera ( Cortaderia spp. Stapf (Poales: Poaceae)). Además, la eficiente crianza en cautive-rio y la alta supervivencia registrada en esta planta hospedera, sugieren que L. australis podría ser usada como un potencial agente de control biológico de esta maleza invasora. Este estudio proporciona informa-ción sobre las etapas inmaduras, incluyendo una clave para su identificación, basada en individuos provenientes de la cría de laboratorio y de campo. PMID:25199992

Linkage and association mapping reveals the genetic basis of brown fibre (Gossypium hirsutum).

Science.gov (United States)

Wen, Tianwang; Wu, Mi; Shen, Chao; Gao, Bin; Zhu, De; Zhang, Xianlong; You, Chunyuan; Lin, Zhongxu

2018-02-24

Brown fibre cotton is an environmental-friendly resource that plays a key role in the textile industry. However, the fibre quality and yield of natural brown cotton are poor, and fundamental research on brown cotton is relatively scarce. To understand the genetic basis of brown fibre cotton, we constructed linkage and association populations to systematically examine brown fibre accessions. We fine-mapped the brown fibre region, Lc 1 , and dissected it into 2 loci, qBF-A07-1 and qBF-A07-2. The qBF-A07-1 locus mediates the initiation of brown fibre production, whereas the shade of the brown fibre is affected by the interaction between qBF-A07-1 and qBF-A07-2. Gh_A07G2341 and Gh_A07G0100 were identified as candidate genes for qBF-A07-1 and qBF-A07-2, respectively. Haploid analysis of the signals significantly associated with these two loci showed that most tetraploid modern brown cotton accessions exhibit the introgression signature of Gossypium barbadense. We identified 10 quantitative trait loci (QTLs) for fibre yield and 19 QTLs for fibre quality through a genome-wide association study (GWAS) and found that qBF-A07-2 negatively affects fibre yield and quality through an epistatic interaction with qBF-A07-1. This study sheds light on the genetics of fibre colour and lint-related traits in brown fibre cotton, which will guide the elite cultivars breeding of brown fibre cotton. © 2018 The Authors. Plant Biotechnology Journal published by Society for Experimental Biology and The Association of Applied Biologists and John Wiley & Sons Ltd.

Effective production of fermentable sugars from brown macroalgae biomass.

Science.gov (United States)

Wang, Damao; Kim, Do Hyoung; Kim, Kyoung Heon

2016-11-01

Brown macroalgae are renewable and sustainable biomass resources for the production of biofuels and chemicals, owing to their high levels of carbohydrates and low levels of lignin. To increase the biological usage of brown macroalgae, it is necessary to depolymerize the polysaccharides that generate macroalgal monomeric sugars or sugar derivatives and to convert them into fermentable sugars for the production of biofuels and chemicals. In this review, we discuss the chemical and enzymatic saccharification of the major carbohydrates found in brown macroalgae and the use of the resulting constituents in the production of biofuels and chemicals, as well as high-value health-benefiting functional oligosaccharides and sugars. We also discuss recently reported experimental results, novel enzymes, and technological breakthroughs that are related to polysaccharide depolymerization, fermentable sugar production, and the biological conversion of non-favorable sugars for fermentation using industrial microorganisms. This review provides a comprehensive perspective of the efficient utilization of brown macroalgae as renewable resources for the production of biofuels and chemicals.

A case of multiple brown tumors with primary hyperparathyroidism.

Science.gov (United States)

Mori, Hiroko; Okada, Yosuke; Arao, Tadashi; Shimaziri, Shohei; Tanaka, Yoshiya

2013-01-01

We report a case of large multiple brown tumors in a patient with primary hyperparathyroidism. A 52-year-old woman suffered from pain in the ribs and developed left facial swelling and deformity. CT showed a large destructive osteolytic lesion in the left maxillary sinus. Biopsy showed a lesion with newly formed bone tissue, diffuse giant cells and deposits of hemosiderin. In addition, similar lesions were also observed in the ribs, iliac bones and pelvis. The laboratory data showed hypercalcemia and hyperparathyroidism. Cervical echo and (201)Tl-(99m)TcO(4-) scintigraphy demonstrated a right lower swollen parathyroid adenoma. The diagnosis was multiple brown tumors with primary hyperparathyroidism and parathyroidectomy was performed. Follow-up CT showed marked decreases in the size of osteolytic lesions with calcification in the brown tumors compared to pre-treatment findings. These changes were associated with marked improvement in pain and facial deformity. We described a rare case of multiple brown tumors appeared in the maxilla associated with primary hyperparathyroidism.

Introgressive hybridization: brown bears as vectors for polar bear alleles.

Science.gov (United States)

Hailer, Frank

2015-03-01

The dynamics and consequences of introgression can inform about numerous evolutionary processes. Biologists have therefore long been interested in hybridization. One challenge, however, lies in the identification of nonadmixed genotypes that can serve as a baseline for accurate quantification of admixture. In this issue of Molecular Ecology, Cahill et al. (2015) analyse a genomic data set of 28 polar bears, eight brown bears and one American black bear. Polar bear alleles are found to be introgressed into brown bears not only near a previously identified admixture zone on the Alaskan Admiralty, Baranof and Chichagof (ABC) Islands, but also far into the North American mainland. Elegantly contrasting admixture levels at autosomal and X chromosomal markers, Cahill and colleagues infer that male-biased dispersal has spread these introgressed alleles away from the Late Pleistocene contact zone. Compared to a previous study on the ABC Island population in which an Alaskan brown bear served as a putatively admixture-free reference, Cahill et al. (2015) utilize a newly sequenced Swedish brown bear as admixture baseline. This approach reveals that brown bears have been impacted by introgression from polar bears to a larger extent (up to 8.8% of their genome), than previously known, including the bear that had previously served as admixture baseline. No evidence for introgression of brown bear into polar bear is found, which the authors argue could be a consequence of selection. Besides adding new exciting pieces to the puzzle of polar/brown bear evolutionary history, the study by Cahill and colleagues highlights that wildlife genomics is moving from analysing single genomes towards a landscape genomics approach. © 2015 John Wiley & Sons Ltd.

The Mechanism of White and Brown Adipocyte Differentiation

Directory of Open Access Journals (Sweden)

Hironori Nakagami

2013-04-01

Full Text Available Obesity gives vent to many diseases such as type 2 diabetes, hypertension, and hyperlipidemia, being considered as the main causes of mortality and morbidity worldwide. The pathogenesis and pathophysiology of metabolic syndrome can well be understood by studying the molecular mechanisms that control the development and function of adipose tissue. In human body, exist two types of adipose tissue, the white and the brown one, which are reported to play various roles in energy homeostasis. The major and most efficient storage of energy occurs in the form of triglycerides in white adipose tissue while brown adipose tissue actively participates in both basal and inducible energy consumption in the form of thermogenesis. Recent years have observed a rapid and greater interest towards developmental plasticity and therapeutic potential of stromal cells those isolated from adipose tissue. The adipocyte differentiation involves a couple of regulators in the white or brown adipogenesis. Peroxisome proliferators-activated receptor-γ actively participates in regulating carbohydrate and lipid metabolism, and also acts as main regulator of both white and brown adipogenesis. This review based on our recent research, seeks to highlight the adipocyte differentiation.

50 years of brown dwarfs from prediction to discovery to forefront of research

CERN Document Server

2014-01-01

The years 2012/2013 mark the 50th anniversary of the theoretical prediction that Brown Dwarfs, i.e. degenerate objects which are just not massive enough to sustain stable hydrogen fusion, exist. Some 20 years after their discovery, how Brown Dwarfs form is still one of the main open questions in the theory of star formation. In this volume, the pioneers of Brown Dwarf research review the history of the theoretical prediction and the subsequent discovery of Brown Dwarfs. After an introduction, written by Viki Joergens, reviewing Shiv Kumar's theoretical prediction of the existence of brown dwarfs, Takenori Nakano reviews his and Hayashi's calculation of the Hydrogen Burning Minimum Mass. Both predictions happened in the early 1960s. Jill Tarter then writes on the introduction of the term 'Brown Dwarf', before Ben Oppenheimer, Rafael Rebolo and Gibor Basri describe their first discovery of Brown Dwarfs in the 1990s. Lastly, Michael Cushing and Isabelle Baraffe describe the development of the field to the curren...

Widespread introgression of mountain hare genes into Fennoscandian brown hare populations.

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Riikka Levänen

Full Text Available In Fennoscandia, mountain hare (Lepus timidus and brown hare (Lepus europaeus hybridize and produce fertile offspring, resulting in gene flow across the species barrier. Analyses of maternally inherited mitochondrial DNA (mtDNA show that introgression occur frequently, but unavailability of appropriate nuclear DNA markers has made it difficult to evaluate the scale- and significance for the species. The extent of introgression has become important as the brown hare is continuously expanding its range northward, at the apparent expense of the mountain hare, raising concerns about possible competition. We report here, based on analysis of 6833 SNP markers, that the introgression is highly asymmetrical in the direction of gene flow from mountain hare to brown hare, and that the levels of nuclear gene introgression are independent of mtDNA introgression. While it is possible that brown hares obtain locally adapted alleles from the resident mountain hares, the low levels of mountain hare alleles among allopatric brown hares suggest that hybridization is driven by stochastic processes. Interspecific geneflow with the brown hare is unlikely to have major impacts on mountain hare in Fennoscandia, but direct competition may.

Approaches to diagnosis and detection of cassava brown streak ...

African Journals Online (AJOL)

Cassava brown streak disease (CBSD) has been a problem in the East African coastal cassava growing areas for more than 70 years. The disease is caused by successful infection with Cassava Brown Streak Virus (CBSV) (Family, Potyviridae: Genus, Ipomovirus). Diagnosis of CBSD has for long been primarily leaf ...

Fermented Brown Rice Flour as Functional Food Ingredient.

Science.gov (United States)

Ilowefah, Muna; Chinma, Chiemela; Bakar, Jamilah; Ghazali, Hasanah M; Muhammad, Kharidah; Makeri, Mohammad

2014-02-12

As fermentation could reduce the negative effects of bran on final cereal products, the utilization of whole-cereal flour is recommended, such as brown rice flour as a functional food ingredient. Therefore, this study aimed to investigate the effect of fermented brown rice flour on white rice flour, white rice batter and its steamed bread qualities. Brown rice batter was fermented using commercial baker's yeast (Eagle brand) according to the optimum conditions for moderate acidity (pH 5.5) to obtain fermented brown rice flour (FBRF). The FBRF was added to white rice flour at 0%, 10%, 20%, 30%, 40% and 50% levels to prepare steamed rice bread. Based on the sensory evaluation test, steamed rice bread containing 40% FBRF had the highest overall acceptability score. Thus, pasting properties of the composite rice flour, rheological properties of its batter, volume and texture properties of its steamed bread were determined. The results showed that peak viscosity of the rice flour containing 40% FBRF was significantly increased, whereas its breakdown, final viscosity and setback significantly decreased. Viscous, elastic and complex moduli of the batter having 40% FBRF were also significantly reduced. However, volume, specific volume, chewiness, resilience and cohesiveness of its steamed bread were significantly increased, while hardness and springiness significantly reduced in comparison to the control. These results established the effectiveness of yeast fermentation in reducing the detrimental effects of bran on the sensory properties of steamed white rice bread and encourage the usage of brown rice flour to enhance the quality of rice products.

Regulation of brown adipocyte metabolism by myostatin/follistatin signaling

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Rajan eSingh

2014-10-01

Full Text Available Obesity develops from perturbations of cellular bioenergetics, when energy uptake exceeds energy expenditure, and represents a major risk factor for the development of type 2 diabetes, dyslipidemia, cardiovascular disease, cancer, and other conditions. Brown adipose tissue (BAT has long been known to dissipate energy as heat and contribute to energy expenditure, but its presence and physiological role in adult human physiology has been questioned for years. Recent demonstrations of metabolically active brown fat depots in adult humans have revolutionized current therapeutic approaches for obesity-related diseases. The balance between white adipose tissue (WAT and BAT affects the systemic energy balance and is widely believed to be the key determinant in the development of obesity and related metabolic diseases. Members of the transforming growth factor-beta (TGF-β superfamily play an important role in regulating overall energy homeostasis by modulation of brown adipocyte characteristics. Inactivation of TGF-β/Smad3/myostatin (Mst signaling promotes browning of white adipocytes, increases mitochondrial biogenesis and protects mice from diet-induced obesity, suggesting the need for development of a novel class of TGF-β/Mst antagonists for the treatment of obesity and related metabolic diseases. We recently described an important role of follistatin (Fst, a soluble glycoprotein that is known to bind and antagonize Mst actions, during brown fat differentiation and the regulation of cellular metabolism. Here we highlight various investigations performed using different in vitro and in vivo models to support the contention that targeting TGF-β/Mst signaling enhances brown adipocyte functions and regulates energy balance, reducing insulin resistance and curbing the development of obesity and diabetes.

SILICATE EVOLUTION IN BROWN DWARF DISKS

International Nuclear Information System (INIS)

Riaz, B.

2009-01-01

We present a compositional analysis of the 10 μm silicate spectra for brown dwarf disks in the Taurus and Upper Scorpius (UppSco) star-forming regions, using archival Spitzer/Infrared Spectrograph observations. A variety in the silicate features is observed, ranging from a narrow profile with a peak at 9.8 μm, to nearly flat, low-contrast features. For most objects, we find nearly equal fractions for the large-grain and crystalline mass fractions, indicating both processes to be active in these disks. The median crystalline mass fraction for the Taurus brown dwarfs is found to be 20%, a factor of ∼2 higher than the median reported for the higher mass stars in Taurus. The large-grain mass fractions are found to increase with an increasing strength in the X-ray emission, while the opposite trend is observed for the crystalline mass fractions. A small 5% of the Taurus brown dwarfs are still found to be dominated by pristine interstellar medium-like dust, with an amorphous submicron grain mass fraction of ∼87%. For 15% of the objects, we find a negligible large-grain mass fraction, but a >60% small amorphous silicate fraction. These may be the cases where substantial grain growth and dust sedimentation have occurred in the disks, resulting in a high fraction of amorphous submicron grains in the disk surface. Among the UppSco brown dwarfs, only usd161939 has a signal-to-noise ratio high enough to properly model its silicate spectrum. We find a 74% small amorphous grain and a ∼26% crystalline mass fraction for this object.

The brown adipocyte differentiation pathway in birds: An evolutionary road not taken

Science.gov (United States)

Mezentseva, Nadejda V; Kumaratilake, Jaliya S; Newman, Stuart A

2008-01-01

Background Thermogenic brown adipose tissue has never been described in birds or other non-mammalian vertebrates. Brown adipocytes in mammals are distinguished from the more common white fat adipocytes by having numerous small lipid droplets rather than a single large one, elevated numbers of mitochondria, and mitochondrial expression of the nuclear gene UCP1, the uncoupler of oxidative phosphorylation responsible for non-shivering thermogenesis. Results We have identified in vitro inductive conditions in which mesenchymal cells isolated from the embryonic chicken limb bud differentiate into avian brown adipocyte-like cells (ABALCs) with the morphological and many of the biochemical properties of terminally differentiated brown adipocytes. Avian, and as we show here, lizard species lack the gene for UCP1, although it is present in amphibian and fish species. While ABALCs are therefore not functional brown adipocytes, they are generated by a developmental pathway virtually identical to brown fat differentiation in mammals: both the common adipogenic transcription factor peroxisome proliferator-activated receptor-γ (PPARγ), and a coactivator of that factor specific to brown fat differentiation in mammals, PGC1α, are elevated in expression, as are mitochondrial volume and DNA. Furthermore, ABALCs induction resulted in strong transcription from a transfected mouse UCP1 promoter. Conclusion These findings strongly suggest that the brown fat differentiation pathway evolved in a common ancestor of birds and mammals and its thermogenicity was lost in the avian lineage, with the degradation of UCP1, after it separated from the mammalian lineage. Since this event occurred no later than the saurian ancestor of birds and lizards, an implication of this is that dinosaurs had neither UCP1 nor canonically thermogenic brown fat. PMID:18426587

37 NEW T-TYPE BROWN DWARFS IN THE CANADA-FRANCE BROWN DWARFS SURVEY

International Nuclear Information System (INIS)

Albert, Loic; Artigau, Etienne; Delorme, Philippe; Reyle, Celine; Forveille, Thierry; Delfosse, Xavier; Willott, Chris J.

2011-01-01

The Canada-France Brown Dwarfs Survey is an i'- and z'-band survey realized with MegaCam at the Canada-France-Hawaii Telescope that covers a surface area of 780 deg 2 . Image analysis is now completed while J-band follow-up campaigns are ∼90% done. The survey identified about 70 T dwarf candidates, of which 43 now have near-infrared spectra obtained with NIRI and GNIRS at Gemini and ISAAC at the Very Large Telescope. Six of these were previously published and we present here the 37 new discoveries, all T dwarfs. They range from T0 to T8.5 with four being of type T7 or later. Both newly identified T8 dwarfs are possibly high log (g) massive brown dwarfs of thin disk age. One T4.5 dwarf shows signs of sub-metallicity. We present proper motions and near-infrared photometry, and discuss about the most peculiar/interesting objects in some details.

Integrated Circuitry: Catharine Brown across Gender, Race, and Religion

Science.gov (United States)

Nelson, Joshua B.

2006-01-01

This article talks about a Cherokee woman named Catharine Brown who was converted to Christianity by missionaries, as well as historical and theoretical contexts regarding the Cherokee. The author presents views from critics, such as Theda Perdue, Carolyn Ross Johnston, and Arnold Krupat, on Catharine Brown's experiences across spheres such as…

Molecular Characterization and Differential Expression of an Olfactory Receptor Gene Family in the White-Backed Planthopper Sogatella furcifera Based on Transcriptome Analysis.

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Ming He

Full Text Available The white-backed planthopper, Sogatella furcifera, a notorious rice pest in Asia, employs host plant volatiles as cues for host location. In insects, odor detection is mediated by two types of olfactory receptors: odorant receptors (ORs and ionotropic receptors (IRs. In this study, we identified 63 SfurORs and 14 SfurIRs in S. furcifera based on sequences obtained from the head transcriptome and bioinformatics analysis. The motif-pattern of 130 hemiptera ORs indicated an apparent differentiation in this order. Phylogenetic trees of the ORs and IRs were constructed using neighbor-joining estimates. Most of the ORs had orthologous genes, but a specific OR clade was identified in S. furcifera, which suggests that these ORs may have specific olfactory functions in this species. Our results provide a basis for further investigations of how S. furcifera coordinates its olfactory receptor genes with its plant hosts, thereby providing a foundation for novel pest management approaches based on these genes.

Chandra Captures Flare From Brown Dwarf

Science.gov (United States)

2000-07-01

The first flare ever seen from a brown dwarf, or failed star, was detected by NASA's Chandra X-ray Observatory. The bright X-ray flare has implications for understanding the explosive activity and origin of magnetic fields of extremely low mass stars. Chandra detected no X-rays at all from LP 944-20 for the first nine hours of a twelve hour observation, then the source flared dramatically before it faded away over the next two hours. "We were shocked," said Dr. Robert Rutledge of the California Institute of Technology in Pasadena, the lead author on the discovery paper to appear in the July 20 issue of Astrophysical Journal Letters. "We didn't expect to see flaring from such a lightweight object. This is really the 'mouse that roared.'" Chandra LP 944-20 X-ray Image Press Image and Caption The energy emitted in the brown dwarf flare was comparable to a small solar flare, and was a billion times greater than observed X-ray flares from Jupiter. The flaring energy is believed to come from a twisted magnetic field. "This is the strongest evidence yet that brown dwarfs and possibly young giant planets have magnetic fields, and that a large amount of energy can be released in a flare," said Dr. Eduardo Martin, also of Caltech and a member of the team. Professor Gibor Basri of the University of California, Berkeley, the principal investigator for this observation, speculated that the flare "could have its origin in the turbulent magnetized hot material beneath the surface of the brown dwarf. A sub-surface flare could heat the atmosphere, allowing currents to flow and give rise to the X-ray flare -- like a stroke of lightning." LP 944-20 is about 500 million years old and has a mass that is about 60 times that of Jupiter, or 6 percent that of the Sun. Its diameter is about one-tenth that of the Sun and it has a rotation period of less than five hours. Located in the constellation Fornax in the southern skies, LP 944-20 is one of the best studied brown dwarfs because it is

Systemic control of brown fat thermogenesis: integration of peripheral and central signals.

Science.gov (United States)

Schulz, Tim J; Tseng, Yu-Hua

2013-10-01

Brown adipose tissue (BAT) is of great scientific interest as a potential target to treat obesity. The development of novel strategies to quantify brown fat thermogenesis in adult humans now enables minimally invasive assessment of novel pharmacotherapeutics. Input from the central nervous system via sympathetic efferents is widely regarded as the key controller of BAT-mediated thermogenesis in response to changes in body temperature or nutrient availability. More recently, however, it has become clear that locally secreted signals and endocrine factors originating from multiple organs can control the recruitment of brown adipocytes and, more importantly, induce thermogenesis in brown fat. Thus, they provide an attractive strategy to fine-tune brown fat thermogenesis independent of classical temperature sensing. Here, we summarize recent findings on bone morphogenetic protein signaling as an example of secreted factors in the regulation of brown adipocyte formation and systemic control of energy metabolism. We further highlight endocrine communication routes between the different types of brown adipocytes and other organs that contribute to regulation of thermogenesis. Thus, emerging evidence suggests that the classical mechanisms of central temperature sensing and sympathetic nervous system-driven thermogenesis are complemented by local and endocrine signals to determine systemic energy homeostasis. © 2013 New York Academy of Sciences.

Improvement Effect of Dewaxed Brown Rice on Constipation in Antibiotic-treated Mice.

Science.gov (United States)

Inagawa, Hiroyuki; Saika, Toshiyuki; Nishiyama, Naoki; Nisizawa, Takashi; Kohchi, Chie; Uenobe, Maya; Soma, Gen-Ichiro

2017-01-01

A decrease in gastrointestinal motility causing weakened lipopolysaccharide (LPS) - toll-like receptor (TLR)4 signaling along with a decline in the number of enteric bacteria is known to be a cause of constipation due to the administration of antibiotics. A new type of brown rice with its wax layer removed, resulting in quick-cooking and tasty product, contains 100-times more LPS than polished white rice. In this study, the improvement effect on constipation due to intake of dewaxed brown rice was examined. Dewaxed brown rice was prepared at Toyo Rice from brown rice. Mice were given powdered feed to which powdered rice containing 0-50% of dewaxed brown rice was added. Antibiotics were administered for 10 or 27 days in drinking water containing vancomycin, metronidazole and neomycin. LPS, used as a control, was freely provided in drinking water. The defecation frequency, stool weight per hour and body weight were determined on the last day. Although the 10-day administration of antibiotics reduced the stool weight per hour to half, the dewaxed brown rice and LPS groups showed a trend towards improvement at a level comparable to the group receiving no antibiotics. The body weight significantly decreased after the 27-day administration of antibiotics but was improved in the 50% dewaxed brown rice group at a level comparable to the group receiving no antibiotics. Though the defecation frequency and wet and dry stool weights per hour were reduced by as much as 50% in the group receiving antibiotics, a significant improvement in constipation was observed in the 50% dewaxed brown rice group. As the improvement effect of dewaxed brown rice on body weight loss and constipation caused by the long-term administration of antibiotics has been confirmed in animal experimentation, the introduction of dewaxed brown rice as a staple food to patients under long-term antibiotic treatment may improve constipation. Copyright© 2017, International Institute of Anticancer Research (Dr

Improvement Effect of Dewaxed Brown Rice on Constipation in Antibiotic-treated Mice

Science.gov (United States)

INAGAWA, HIROYUKI; SAIKA, TOSHIYUKI; NISHIYAMA, NAOKI; NISIZAWA, TAKASHI; KOHCHI, CHIE; UENOBE, MAYA; SOMA, GEN-ICHIRO

2017-01-01

Background/Aim: A decrease in gastrointestinal motility causing weakened lipopolysaccharide (LPS) – toll-like receptor (TLR)4 signaling along with a decline in the number of enteric bacteria is known to be a cause of constipation due to the administration of antibiotics. A new type of brown rice with its wax layer removed, resulting in quick-cooking and tasty product, contains 100-times more LPS than polished white rice. In this study, the improvement effect on constipation due to intake of dewaxed brown rice was examined. Materials and Methods: Dewaxed brown rice was prepared at Toyo Rice from brown rice. Mice were given powdered feed to which powdered rice containing 0-50% of dewaxed brown rice was added. Antibiotics were administered for 10 or 27 days in drinking water containing vancomycin, metronidazole and neomycin. LPS, used as a control, was freely provided in drinking water. The defecation frequency, stool weight per hour and body weight were determined on the last day. Results: Although the 10-day administration of antibiotics reduced the stool weight per hour to half, the dewaxed brown rice and LPS groups showed a trend towards improvement at a level comparable to the group receiving no antibiotics. The body weight significantly decreased after the 27-day administration of antibiotics but was improved in the 50% dewaxed brown rice group at a level comparable to the group receiving no antibiotics. Though the defecation frequency and wet and dry stool weights per hour were reduced by as much as 50% in the group receiving antibiotics, a significant improvement in constipation was observed in the 50% dewaxed brown rice group. Conclusion: As the improvement effect of dewaxed brown rice on body weight loss and constipation caused by the long-term administration of antibiotics has been confirmed in animal experimentation, the introduction of dewaxed brown rice as a staple food to patients under long-term antibiotic treatment may improve constipation. PMID

Management of brown bears (Ursus arctos) in Europe.

OpenAIRE

Klenzendorf, Sybille A.

1997-01-01

Management of Brown Bears (Ursus arctos) in Europe. Sybille A. Klenzendorf (Abstract) Successful conservation of brown bears (Ursus arctos) in Europe is associated with public acceptance of damages caused by bears. Recent increases in sheep depredation and beehive damage in central Austria resulted in the deaths of two bears there. Since bear numbers are low in most European populations, alternatives to the elimination of problem bears associated with dam...

Highly Viscous States Affect the Browning of Atmospheric Organic Particulate Matter.

Science.gov (United States)

Liu, Pengfei; Li, Yong Jie; Wang, Yan; Bateman, Adam P; Zhang, Yue; Gong, Zhaoheng; Bertram, Allan K; Martin, Scot T

2018-02-28

Initially transparent organic particulate matter (PM) can become shades of light-absorbing brown via atmospheric particle-phase chemical reactions. The production of nitrogen-containing compounds is one important pathway for browning. Semisolid or solid physical states of organic PM might, however, have sufficiently slow diffusion of reactant molecules to inhibit browning reactions. Herein, organic PM of secondary organic material (SOM) derived from toluene, a common SOM precursor in anthropogenically affected environments, was exposed to ammonia at different values of relative humidity (RH). The production of light-absorbing organonitrogen imines from ammonia exposure, detected by mass spectrometry and ultraviolet-visible spectrophotometry, was kinetically inhibited for RH atmospheric brown carbon production and associated influences on energy balance.

Chewing lice Trichodectes pinguis pinguis in Scandinavian brown bears (Ursus arctos

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Núria Fandos Esteruelas

2016-08-01

Full Text Available In April 2014 and 2015, we noted localized alopecia (neck, forelimbs, and chest and hyperpigmentation on two adult brown bears (Ursus arctos captured in central-south Sweden for ecological studies under the Scandinavian Brown Bear Research Project. In spring 2015, a brown bear was shot because of human-wildlife conflict in the same region. This bear also had extensive alopecia and hyperpigmentation. Ectoparasites were collected from the affected skin areas in all three individuals and preserved in ethanol for identification. Based on morphological characteristics, the lice were identified as Trichodectes spp. and Trichodectes pinguis pinguis. To our knowledge, these are the first reported cases of chewing lice in free-ranging brown bears in Scandinavia.

Brown dwarf accretion: Nonconventional star formation over very long timescales

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Ćirković Milan M.

2005-01-01

Full Text Available We investigate the process of accretion of interstellar gas by the Galactic population of brown dwarfs over very long timescales typical for physical eschatology. In particular, we use the classical Hoyle-Lyttleton-Bondi accretion model to investigate the rate at which brown dwarfs collect enough additional mass to become red dwarfs, accretion-induced changes in the mass function of the low- mass objects, and the corresponding accretion heating of brown dwarfs. In addition, we show how we can make the definition of the final mass function for stellar objects more precise.

Degradation of brown adipocyte purine nucleotides regulates uncoupling protein 1 activity

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Tobias Fromme

2018-02-01

Full Text Available Objective: Non-shivering thermogenesis in mammalian brown adipose tissue depends on thermogenic uncoupling protein 1. Its activity is triggered by free fatty acids while purine nucleotides mediate inhibition. During activation, it is thought that free fatty acids overcome purine-mediated inhibition. We measured the cellular concentration and the release of purine nucleotide metabolites to uncover a possible role of purine nucleotide degradation in uncoupling protein 1 activation. Methods: With mass spectrometry, purine nucleotide metabolites were quantified in cellular homogenates and supernatants of cultured primary brown adipocytes. We also determined oxygen consumption in response to a β-adrenergic agonist. Results: Upon adrenergic activation, brown adipocytes decreased the intracellular concentration of inhibitory nucleotides (ATP, ADP, GTP and GDP and released the respective degradation products. At the same time, an increase in cellular calcium occurred. None of these phenomena occurred in white adipocytes or myotubes. The brown adipocyte expression of enzymes implicated in purine metabolic remodeling is altered upon cold exposure. Pharmacological and genetic interference of purine metabolism altered uncoupling protein 1 mediated uncoupled respiration. Conclusion: Adrenergic stimulation of brown adipocytes lowers the intracellular concentration of purine nucleotides, thereby contributing to uncoupling protein 1 activation. Keywords: Purine nucleotides, Uncoupling protein 1, Brown adipose tissue, Non-shivering thermogenesis, HILIC-MS/MS, Guanosine monophosphate reductase

Intravitreally Injected Anti-VEGF Antibody Reduces Brown Fat in Neonatal Mice.

Science.gov (United States)

Jo, Dong Hyun; Park, Sung Wook; Cho, Chang Sik; Powner, Michael B; Kim, Jin Hyoung; Fruttiger, Marcus; Kim, Jeong Hun

2015-01-01

Anti-vascular endothelial growth factor (VEGF) agents are the mainstay treatment for various angiogenesis-related retinal diseases. Currently, bevacizumab, a recombinant humanized anti-VEGF antibody, is trailed in retinopathy of prematurity, a vasoproliferative retinal disorder in premature infants. However, the risks of systemic complications after intravitreal injection of anti-VEGF antibody in infants are not well understood. In this study, we show that intravitreally injected anti-VEGF antibody is transported into the systemic circulation into the periphery where it reduces brown fat in neonatal C57BL/6 mice. A considerable amount of anti-VEGF antibody was detected in serum after intravitreal injection. Furthermore, in interscapular brown adipose tissue, we found lipid droplet accumulation, decreased VEGF levels, loss of vascular network, and decreased expression of mitochondria-related genes, Ppargc1a and Ucp1, all of which are characteristics of "whitening" of brown fat. With increasing age and body weight, brown fat restored its morphology and vascularity. Our results show that there is a transient, but significant impact of intravitreally administered anti-VEGF antibody on brown adipose tissue in neonatal mice. We suggest that more attention should be focused on the metabolic and developmental significance of brown adipose tissue in bevacizumab treated retinopathy of prematurity infants.

Intravitreally Injected Anti-VEGF Antibody Reduces Brown Fat in Neonatal Mice.

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Dong Hyun Jo

Full Text Available Anti-vascular endothelial growth factor (VEGF agents are the mainstay treatment for various angiogenesis-related retinal diseases. Currently, bevacizumab, a recombinant humanized anti-VEGF antibody, is trailed in retinopathy of prematurity, a vasoproliferative retinal disorder in premature infants. However, the risks of systemic complications after intravitreal injection of anti-VEGF antibody in infants are not well understood. In this study, we show that intravitreally injected anti-VEGF antibody is transported into the systemic circulation into the periphery where it reduces brown fat in neonatal C57BL/6 mice. A considerable amount of anti-VEGF antibody was detected in serum after intravitreal injection. Furthermore, in interscapular brown adipose tissue, we found lipid droplet accumulation, decreased VEGF levels, loss of vascular network, and decreased expression of mitochondria-related genes, Ppargc1a and Ucp1, all of which are characteristics of "whitening" of brown fat. With increasing age and body weight, brown fat restored its morphology and vascularity. Our results show that there is a transient, but significant impact of intravitreally administered anti-VEGF antibody on brown adipose tissue in neonatal mice. We suggest that more attention should be focused on the metabolic and developmental significance of brown adipose tissue in bevacizumab treated retinopathy of prematurity infants.

Fuel briquettes from brown coals of Yakutia

Energy Technology Data Exchange (ETDEWEB)

L.A. Nikolaeva; V.G. Latyshev; O.N. Burenina [Russian Academy of Sciences, Yakutsk (Russian Federation). Institute of Oil and Gas Problems

2009-04-15

Experimental data on the development of technology for the manufacture of briquetted fuel from brown coals with the use of various petroleum binders are presented. The influence of the moisture content, the coal particle-size composition, the binder type and concentration, the compacting pressure, and heat treatment regimes on the mechanical properties of the materials was studied. The optimal compositions and optimal values of the engineering parameters for the production of graded briquetted fuel from brown coals of the Kangalassy deposit in the Republic of Sakha (Yakutia) were established.

Brown dwarfs in retrogradely precessing cataclysmic variables?

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Martin E.L.

2011-07-01

Full Text Available We compare Smoothed Particle Hydrodynamic simulations of retrogradely precessing accretion disks that have a white dwarf primary and a main sequence secondary with observational data and with theory on retrograde precession via tidal torques like those by the Moon and the Sun on the Earth [1, 2]. Assuming the primary does not accrete much of the mass lost from the secondary, we identify the theoretical low mass star/brown dwarf boundary. We find no observational candidates in our study that could qualify as brown dwarfs.

Cellulose Degradation by Cellulose-Clearing and Non-Cellulose-Clearing Brown-Rot Fungi

OpenAIRE

Highley, Terry L.

1980-01-01

Cellulose degradation by four cellulose-clearing brown-rot fungi in the Coniophoraceae—Coniophora prasinoides, C. puteana, Leucogyrophana arizonica, and L. olivascens—is compared with that of a non-cellulose-clearing brown-rot fungus, Poria placenta. The cellulose- and the non-cellulose-clearing brown-rot fungi apparently employ similar mechanisms to depolymerize cellulose; most likely a nonenzymatic mechanism is involved.

Constraints on the brown dwarf mass function from optical and infrared searches

International Nuclear Information System (INIS)

Probst, R.G.

1986-01-01

Photometric surveys of faint proper motion stars and searches for infrared binary companions have identified a few very low luminosity objects. The author considers how these searches may constrain the brown dwarf mass function. An astrophysically plausible brown dwarf population is defined which yields a dark mass density = 0.5 x the observed density. Using the sensitivity and other limits of various surveys, the expected numbers of observable brown dwarfs are obtained from the model population for comparison with actual results. Reasonable improvement in search protocol could yield statistically significant tests of the brown dwarf mass function. (author)

Brown and Beige Fat: Molecular Parts of a Thermogenic Machine.

Science.gov (United States)

Cohen, Paul; Spiegelman, Bruce M

2015-07-01

The epidemic of obesity and type 2 diabetes has increased interest in pathways that affect energy balance in mammalian systems. Brown fat, in all of its dimensions, can increase energy expenditure through the dissipation of chemical energy in the form of heat, using mitochondrial uncoupling and perhaps other pathways. We discuss here some of the thermodynamic and cellular aspects of recent progress in brown fat research. This includes studies of developmental lineages of UCP1(+) adipocytes, including the discovery of beige fat cells, a new thermogenic cell type. We also discuss the physiology and transcriptional control of brown and beige cells in rodents and the state of current knowledge about human brown fat. © 2015 by the American Diabetes Association. Readers may use this article as long as the work is properly cited, the use is educational and not for profit, and the work is not altered.

Students Use VLA to Make Startling Brown-Dwarf Discovery

Science.gov (United States)

2001-03-01

A group of summer students making a long-shot astronomical gamble with the National Science Foundation's (NSF) Very Large Array (VLA) have found the first radio emission ever detected from a brown dwarf, an enigmatic object that is neither a star nor a planet, but something in between. Their surprising discovery is forcing experts to re-think their theories about how brown dwarfs work. The Very Large Array "Many astronomers are surprised at this discovery, because they didn't expect such strong radio emission from this object," said Shri Kulkarni, a Caltech professor who was on the team that first discovered a brown dwarf in 1995, and advisor to one of the students. "What is so cool is that this is research that probably nobody else would have tried to do because of its low chance of success. That made it ideal for summer students -- we had almost nothing to lose," said Kate Becker, a student at Oberlin College in Ohio. "The radio emission these students discovered coming from this brown dwarf is 10,000 times stronger than anyone expected," said Dale Frail, an astronomer at the National Radio Astronomy Observatory (NRAO) in Socorro, NM. "This student project is going to open up a whole new area of research for the VLA," Frail added. The students, in addition to Becker, are: Edo Berger from Caltech; Steven Ball from New Mexico Tech in Socorro, NM; Melanie Clarke from Carleton College in Northfield, MN; Therese Fukuda from the University of Denver; Ian Hoffman from the University of New Mexico in Albuquerque; Richard Mellon from The Pennsylvania State University; Emmanuel Momjian from the University of Kentucky; Nathanial Murphy from Amherst College in Amherst, MA; Stacey Teng from the University of Maryland; Timothy Woodruff from Southwestern University in Georgetown, TX; Ashley Zauderer from Agnes Scott College in Decatur, GA; and Robert Zavala from New Mexico State University in Las Cruces, NM. Frail also is an author of the research paper, published in the March

A fusion protein containing a lepidopteran-specific toxin from the South Indian red scorpion (Mesobuthus tamulus and snowdrop lectin shows oral toxicity to target insects

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Fitches Elaine

2006-03-01

Full Text Available Abstract Background Despite evidence suggesting a role in plant defence, the use of plant lectins in crop protection has been hindered by their low and species-specific insecticidal activity. Snowdrop lectin (Galanthus nivalis agglutinin; GNA is transported to the haemolymph of insects after oral ingestion, and can be used as a basis for novel insecticides. Recombinant proteins containing GNA expressed as a fusion with a peptide or protein, normally only toxic when injected into the insect haemolymph, have the potential to show oral toxicity as a result of GNA-mediated uptake. Results A gene encoding a toxin, ButaIT, from the red scorpion (Mesobuthus tamulus was synthesised and assembled into expression constructs. One construct contained ButaIT alone, whereas the other contained ButaIT fused N-terminally to a GNA polypeptide (ButaIT/GNA. Both recombinant proteins were produced using the yeast Pichia pastoris as an expression host, and purified. Recombinant ButaIT and ButaIT/GNA were acutely toxic when injected into larvae of tomato moth (Lacanobia oleracea, causing slow paralysis, leading to mortality or decreased growth. ButaIT/GNA was chronically toxic when fed to L. oleracea larvae, causing decreased survival and weight gain under conditions where GNA alone was effectively non-toxic. Intact ButaIT/GNA was detected in larval haemolymph from insects fed the fusion protein orally, demonstrating transport of the linked polypeptide across the gut. Proteolysis of the fusion protein was also observed. ButaIT/GNA was significantly more toxic that GNA alone when fed to the homopteran Nilaparvata lugens (rice brown planthopper in liquid artificial diet. Conclusion The ButaIT/GNA recombinant fusion protein is toxic to lepidopteran larvae both when injected and when fed orally, showing the utility of GNA as a carrier to transport potentially toxic peptides and proteins across the insect gut. Although ButaIT has been claimed to be lepidopteran

A Very Cool Pair of Brown Dwarfs

Science.gov (United States)

2011-03-01

Observations with the European Southern Observatory's Very Large Telescope, along with two other telescopes, have shown that there is a new candidate for the coldest known star: a brown dwarf in a double system with about the same temperature as a freshly made cup of tea - hot in human terms, but extraordinarily cold for the surface of a star. This object is cool enough to begin crossing the blurred line dividing small cold stars from big hot planets. Brown dwarfs are essentially failed stars: they lack enough mass for gravity to trigger the nuclear reactions that make stars shine. The newly discovered brown dwarf, identified as CFBDSIR 1458+10B, is the dimmer member of a binary brown dwarf system located just 75 light-years from Earth [1]. The powerful X-shooter spectrograph on ESO's Very Large Telescope (VLT) was used to show that the composite object was very cool by brown dwarf standards. "We were very excited to see that this object had such a low temperature, but we couldn't have guessed that it would turn out to be a double system and have an even more interesting, even colder component," said Philippe Delorme of the Institut de planétologie et d'astrophysique de Grenoble (CNRS/Université Joseph Fourier), a co-author of the paper. CFBDSIR 1458+10 is the coolest brown dwarf binary found to date. The dimmer of the two dwarfs has now been found to have a temperature of about 100 degrees Celsius - the boiling point of water, and not much different from the temperature inside a sauna [2]. "At such temperatures we expect the brown dwarf to have properties that are different from previously known brown dwarfs and much closer to those of giant exoplanets - it could even have water clouds in its atmosphere," said Michael Liu of the University of Hawaii's Institute for Astronomy, who is lead author of the paper describing this new work. "In fact, once we start taking images of gas-giant planets around Sun-like stars in the near future, I expect that many of them

Platelet function in brown bear (Ursus arctos compared to man

Directory of Open Access Journals (Sweden)

Särndahl Eva

2010-06-01

Full Text Available Abstract Background Information on hemostasis and platelet function in brown bear (Ursus arctos is of importance for understanding the physiological, protective changes during hibernation. Objective The study objective was to document platelet activity values in brown bears shortly after leaving the den and compare them to platelet function in healthy humans. Methods Blood was drawn from immobilized wild brown bears 7-10 days after leaving the den in mid April. Blood samples from healthy human adults before and after clopidogrel and acetylsalicylic acid administration served as control. We analyzed blood samples by standard blood testing and platelet aggregation was quantified after stimulation with various agonists using multiple electrode aggregometry within 3 hours of sampling. Results Blood samples were collected from 6 bears (3 females between 1 and 16 years old and from 10 healthy humans. Results of adenosine diphosphate, aspirin, and thrombin receptor activating peptide tests in bears were all half or less of those in humans. Platelet and white blood cell counts did not differ between species but brown bears had more and smaller red blood cells compared with humans. Conclusion Using three different tests, we conclude that platelet function is lower in brown bears compared to humans. Our findings represent the first descriptive study on platelet function in brown bears and may contribute to explain how bears can endure denning without obvious thrombus building. However, the possibility that our findings reflect test-dependent and not true biological variations in platelet reactivity needs further studies.

Transcriptomic events associated with internal browning of apple during postharvest storage

OpenAIRE

Mellidou, Ifigeneia; Buts, Kim; Hatoum, Darwish; Ho, Quang Tri; Johnston, Jason W; Watkins, Christopher B; Schaffer, Robert J; Gapper, Nigel E; Giovannoni, Jim J; Rudell, David R; Hertog, Maarten LATM; Nicolai, Bart M

2014-01-01

Background Postharvest ripening of apple (Malus x domestica) can be slowed down by low temperatures, and a combination of low O2 and high CO2 levels. While this maintains the quality of most fruit, occasionally storage disorders such as flesh browning can occur. This study aimed to explore changes in the apple transcriptome associated with a flesh browning disorder related to controlled atmosphere storage using RNA-sequencing techniques. Samples from a browning-susceptible cultivar (‘Braeburn...

Sorghum Brown Midrib Mutants, Tools to Improve Biomass for Biofuels

Science.gov (United States)

To improve sorghum for cellulosic bioenergy uses, brown midrib mutants are being investigated for their ability to increase the conversion efficiency of biomass. brown midrib 6 and 12 (bmr6 and 12) mutants affect monolignol biosynthesis resulting in reduced lignin content and altered lignin composi...

Agaricus bisporus browning: a review

NARCIS (Netherlands)

Jolivet, S.; Arpin, N.; Wichers, H.J.; Pellon, G.

1998-01-01

Agaricus bisporus browning is a common and economically detrimental phenomenon, in which melanogenic phenols are enzymically processed into quinones, which evolve eventually to melanins. This review deals with the two fundamental sides of this process, enzyme(s) and phenolic substrates. Mushroom

Cold-Inducible SIRT6 Regulates Thermogenesis of Brown and Beige Fat

Directory of Open Access Journals (Sweden)

Lu Yao

2017-07-01

Full Text Available Promoting development and function of brown and beige fat may reduce obesity. Here, we show that fat SIRT6 expression is markedly induced by cold exposure and a β-adrenergic agonist. Deletion of SIRT6 in adipose tissue impairs the thermogenic function of brown adipocytes, causing a morphological “whitening” of brown fat, reduced oxygen (O2 consumption, obesity, decreased core body temperature, and cold sensitivity. Fat SIRT6-deleted mice exhibit increased blood glucose levels, severe insulin resistance, and hepatic steatosis. Moreover, SIRT6 deficiency inhibits the browning of white adipose tissue (WAT following cold exposure or β3-agonist treatment. Depletion of SIRT6 expression in brown adipocytes reduces expression of thermogenic genes, causing a reduction in cellular respiration. Conversely, SIRT6 overexpression in primary fat cells stimulates the thermogenic program. Mechanistically, SIRT6 interacts with and promotes phospho-ATF2 binding to the PGC-1α gene promoter to activate its expression. The present study reveals a critical role for SIRT6 in regulating thermogenesis of fat.

SERUM ACETYLCHOLINESTERASE LEVEL IN THE PATIENTS OF OPIOID (BROWN SUGAR) DEPENDENCE

OpenAIRE

Shah, Nilesh; Dave, Kirti

1992-01-01

The authors compared the serum acetylcholinesterase level in the patients of brown sugar dependence and the normal volunteers. Significantly lower level of serum acetylcholinesterase was found in patients of brown sugar dependence.

Central Fibroblast Growth Factor 21 Browns White Fat via Sympathetic Action in Male Mice.

Science.gov (United States)

Douris, Nicholas; Stevanovic, Darko M; Fisher, Ffolliott M; Cisu, Theodore I; Chee, Melissa J; Nguyen, Ngoc L; Zarebidaki, Eleen; Adams, Andrew C; Kharitonenkov, Alexei; Flier, Jeffrey S; Bartness, Timothy J; Maratos-Flier, Eleftheria

2015-07-01

Fibroblast growth factor 21 (FGF21) has multiple metabolic actions, including the induction of browning in white adipose tissue. Although FGF21 stimulated browning results from a direct interaction between FGF21 and the adipocyte, browning is typically associated with activation of the sympathetic nervous system through cold exposure. We tested the hypothesis that FGF21 can act via the brain, to increase sympathetic activity and induce browning, independent of cell-autonomous actions. We administered FGF21 into the central nervous system via lateral ventricle infusion into male mice and found that the central treatment increased norepinephrine turnover in target tissues that include the inguinal white adipose tissue and brown adipose tissue. Central FGF21 stimulated browning as assessed by histology, expression of uncoupling protein 1, and the induction of gene expression associated with browning. These effects were markedly attenuated when mice were treated with a β-blocker. Additionally, neither centrally nor peripherally administered FGF21 initiated browning in mice lacking β-adrenoceptors, demonstrating that an intact adrenergic system is necessary for FGF21 action. These data indicate that FGF21 can signal in the brain to activate the sympathetic nervous system and induce adipose tissue thermogenesis.

Speciation and Localization of Arsenic in White and Brown Rice Grains

Energy Technology Data Exchange (ETDEWEB)

Meharg, Andrew A.; Lombi, Enzo; Williams, Paul N.; Scheckel, Kirk G.; Feldmann, Joerg; Raab, Andrea; Zhu, Yongguan; Islam, Rafiql (EPA); (Bangladesh); (UCopenhagen); (Aberdeen); (Chinese Aca. Sci.)

2008-06-30

Synchrotron-based X-ray fluorescence (S-XRF) was utilized to locate arsenic (As) in polished (white) and unpolished (brown) rice grains from the United States, China, and Bangladesh. In white rice As was generally dispersed throughout the grain, the bulk of which constitutes the endosperm. In brown rice As was found to be preferentially localized at the surface, in the region corresponding to the pericarp and aleurone layer. Copper, iron, manganese, and zinc localization followed that of arsenic in brown rice, while the location for cadmium and nickel was distinctly different, showing relatively even distribution throughout the endosperm. The localization of As in the outer grain of brown rice was confirmed by laser ablation ICP?MS. Arsenic speciation of all grains using spatially resolved X-ray absorption near edge structure (?-XANES) and bulk extraction followed by anion exchange HPLC?ICP?MS revealed the presence of mainly inorganic As and dimethylarsinic acid (DMA). However, the two techniques indicated different proportions of inorganic:organic As species. A wider survey of whole grain speciation of white (n = 39) and brown (n = 45) rice samples from numerous sources (field collected, supermarket survey, and pot trials) showed that brown rice had a higher proportion of inorganic arsenic present than white rice. Furthermore, the percentage of DMA present in the grain increased along with total grain arsenic.

Insect resistance to Nilaparvata lugens and Cnaphalocrocis medinalis in transgenic indica rice and the inheritance of gna+sbti transgenes.

Science.gov (United States)

Li, Guiying; Xu, Xinping; Xing, Hengtai; Zhu, Huachen; Fan, Qin

2005-04-01

Molecular genetic analysis and insect bioassay of transgenic indica rice 'Zhuxian B' plants carrying snowdrop lectin gene (gna) and soybean trypsin inhibitor gene (sbti) were investigated in detail. PCR, 'dot' blot and PCR-Southern blot analysis showed that both transgenes had been incorporated into the rice genome and transmitted up to R3 progeny in most lines tested. Some transgenic lines exhibited Mendelian segregation, but the other showed either 1:1 (positive: negative for the transgenes) or other aberrant segregation patterns. The segregation patterns of gna gene crossed between R2 and R3 progeny. In half of transgenic R3 lines, gna and sbti transgenes co-segregated. Two independent homozygous lines expressing double transgenes were identified in R3 progeny. Southern blot analysis demonstrated that the copy numbers of integrated gna and sbti transgenes varied from one to ten in different lines. Insect bioassay data showed that most transgenic plants had better resistance to both Nilaparvata lugens (Stahl) and Cnaphalocrocis medinalis (Guenee) than wild-type plants. The insect resistance of transgenic lines increased with the increase in transgene positive ratio in most of the transgenic lines. In all, we obtained nine lines of R3 transgenic plants, including one pure line, which had better resistance to both N lugens and C medinalis than wild-type plants. Copyright 2005 Society of Chemical Industry.

Browning of Subcutaneous White Adipose Tissue in Humans

OpenAIRE

Sidossis, Labros S.; Porter, Craig; Saraf, Manish K.; Børsheim, Elisabet; Radhakrishnan, Ravi S.; Chao, Tony; Ali, Arham; Chondronikola, Maria; Mlcak, Ronald; Finnerty, Celeste C.; Hawkins, Hal K.; Toliver-Kinsky, Tracy; Herndon, David N.

2015-01-01

Since the presence of brown adipose tissue (BAT) was confirmed in adult humans, BAT has become a therapeutic target for obesity and insulin resistance. We examined whether human subcutaneous white adipose tissue (sWAT) can adopt a BAT-like phenotype using a clinical model of prolonged and severe adrenergic stress. sWAT samples were collected from severely burned and healthy individuals. A subset of burn victims were prospectively followed during their acute hospitalization. Browning of sWAT w...

Broad-scale patterns of Brook Trout responses to introduced Brown Trout in New York

Science.gov (United States)

McKenna, James E.; Slattery, Michael T.; Kean M. Clifford,

2013-01-01

Brook Trout Salvelinus fontinalis and Brown Trout Salmo trutta are valuable sport fish that coexist in many parts of the world due to stocking introductions. Causes for the decline of Brook Trout within their native range are not clear but include competition with Brown Trout, habitat alteration, and repetitive stocking practices. New York State contains a large portion of the Brook Trout's native range, where both species are maintained by stocking and other management actions. We used artificial neural network models, regression, principal components analysis, and simulation to evaluate the effects of Brown Trout, environmental conditions, and stocking on the distribution of Brook Trout in the center of their native range. We found evidence for the decline of Brook Trout in the presence of Brown Trout across many watersheds; 22% of sampled reaches where both species were expected to occur contained only Brown Trout. However, a model of the direct relationship between Brook Trout and Brown Trout abundance explained less than 1% of data variation. Ordination showed extensive overlap of Brook Trout and Brown Trout habitat conditions, with only small components of the hypervolume (multidimensional space) being distinctive. Subsequent analysis indicated higher abundances of Brook Trout in highly forested areas, while Brown Trout were more abundant in areas with relatively high proportions of agriculture. Simulation results indicated that direct interactions and habitat conditions were relatively minor factors compared with the effects of repeated stocking of Brown Trout into Brook Trout habitat. Intensive annual stocking of Brown Trout could eliminate resident Brook Trout in less than a decade. Ecological differences, harvest behavior, and other habitat changes can exacerbate Brook Trout losses. Custom stocking scenarios with Brown Trout introductions at relatively low proportions of resident Brook Trout populations may be able to sustain healthy populations of both

Plume trajectory validation study: Brown cloud support project overview

International Nuclear Information System (INIS)

Brown-Strattan, M.A.; Smith, M.L.

1991-01-01

The brown cloud is an air pollution phenomenon of great concern to the Denver metropolitan area. Regulatory agencies, academia, and research organizations are involved in characterizing the development and transport of the brown cloud and identifying mitigation approaches. In support of this effort, NOAA conducted releases of small (one cubic meter) constant density balloons from sites in Denver and along the South Platte Valley. These balloons, called ''tetroons'' because of their tetrahedral shape, carried five-ounce transponders and were tracked by radar as they rose to predetermined altitudes and followed airflow patterns at those altitudes. The data gathered from these releases included the geographic position and altitude of each tetroon over time. These data will aid efforts to understand brown cloud development, structure, and transport

Brown tumor mimicking maxillary sinus mucocele as the first manifestation of primary hyperparathyroidism

DEFF Research Database (Denmark)

Guldfred, Liviu-Adelin; Daugaard, Søren; von Buchwald, Christian

2012-01-01

We describe the first case of brown tumor mimicking a maxillary sinus mucocele as the first manifestation of the patient's primary hyperparathyroidism. A 34-year old woman presented with a 14 days history of elevation of the right orbit, retrobulbar pain and cheek anesthesia. The CT and MR evalua...... either giant cell granuloma or brown tumor. The finding of hyperparathyroidism confirmed the diagnosis of brown tumor. To our knowledge, this is the first report of cystic brown tumor mimicking a mucocele of the maxillary sinus....

Connecting Young Brown Dwarfs and Directly Imaged Gas-Giant Planets

Science.gov (United States)

Liu, Michael; Dupuy, Trent; Allers, Katelyn; Aller, Kimberly; Best, William; Magnier, Eugene

2015-12-01

Direct detections of gas-giant exoplanets and discoveries of young (~10-100 Myr) field brown dwarfs from all-sky surveys are strengthening the link between the exoplanet and brown dwarf populations, given the overlapping ages, masses, temperatures, and surface gravities. In light of the relatively small number of directly imaged planets and the modest associated datasets, the large census of young field brown dwarfsprovides a compelling laboratory for enriching our understanding of both classes of objects. However, work to date on young field objects has typically focused on individual discoveries.We present a large comprehensive study of the youngest field brown dwarfs, comprising both previously known objects and our new discoveries from the latest wide-field surveys (Pan-STARRS-1 and WISE). With masses now extending down to ~5 Jupiter masses, these objects have physical properties that largely overlap young gas-giant planets and thus are promising analogs for studying exoplanet atmospheres at unparalleled S/N, spectral resolution, and wavelength coverage. We combine high-quality spectra and parallaxes to determine spectral energy distributions, luminosities, temperatures, and ages for young field objects. We demonstrate that this population spans a continuum in the color-magnitude diagram, thereby forming a bridge between the hot and cool extremes of directly imaged planets. We find that the extremely dusty properties of the planets around 2MASS J1207-39 and HR 8799 do occur in some young brown dwarfs, but these properties do not have a simple correspondence with age, perhaps contrary to expectations. We find young field brown dwarfs can have unusually low temperatures and suggest a new spectral type-temperature scale appropriate for directly imaged planets.To help provide a reference for extreme-contrast imaging surveys, we establish a grid of spectral standards and benchmarks, based on membership in nearby young moving groups, in order to calibrate gravity

Utilization of brown coal in FRG power plants

Energy Technology Data Exchange (ETDEWEB)

Kotler, V.R.

1985-07-01

FRG methods are studied for utilizing brown coal in view of the development of Kansk-Achinsk brown coal deposits. The use of brown coal in FRG power plants has increased from 15% in 1950- 1960 to 85% (total output) in 1982, providing 79.4 TWh of electrical energy. The remainder was used for briquetting, pulverization and breeze coke. In 1982 nearly 100 million tons of brown coal were burned by six large power stations (rated capacity 11,400 MW) to produce nearly 80 billion kWh of energy. Measures are discussed taken to reduce slagging and to remove excessive moisture content. Problems are analyzed associated with increased contamination of the atmosphere in areas with high population density (412/km/sup 2/) and cost of suppression is reviewed. According to available data, the cost of preventive measures taken by FRG, USA, Japan and the Netherlands is equal to 30% of the total cost of the energy. The most critical problem is suppression of sulfur dioxide, either by dry or wet scrubbers or by the addition of dry dolomite or lime to the furnace (75% of all SO/sub 2/ emissions in FRG comes from power stations). A method is described developed by RWE based on a series of distribution headers in the upper part of combustion chambers. At best, 70-80% reduction can be achieved. 14 references.

Playing with Father: Anthony Browne's Picture Books and the Masculine.

Science.gov (United States)

Bradford, Clare

1998-01-01

Concentrates on the father figures in Anthony Browne's books and on the ways in which gender ideologies are encoded in works dealing with family relationships, concentrating on "Zoo" and "The Big Baby," but also looking at "Gorilla" and "Piggybook." Finds that the diversity of Browne's work provides children…

Clozapine modifies the differentiation program of human adipocytes inducing browning.

Science.gov (United States)

Kristóf, E; Doan-Xuan, Q-M; Sárvári, A K; Klusóczki, Á; Fischer-Posovszky, P; Wabitsch, M; Bacso, Z; Bai, P; Balajthy, Z; Fésüs, L

2016-11-29

Administration of second-generation antipsychotic drugs (SGAs) often leads to weight gain and consequent cardio-metabolic side effects. We observed that clozapine but not six other antipsychotic drugs reprogrammed the gene expression pattern of differentiating human adipocytes ex vivo, leading to an elevated expression of the browning marker gene UCP1, more and smaller lipid droplets and more mitochondrial DNA than in the untreated white adipocytes. Laser scanning cytometry showed that up to 40% of the differentiating single primary and Simpson-Golabi-Behmel syndrome (SGBS) adipocytes had the characteristic morphological features of browning cells. Furthermore, clozapine significantly upregulated ELOVL3, CIDEA, CYC1, PGC1A and TBX1 genes but not ZIC1 suggesting induction of the beige-like and not the classical brown phenotype. When we tested whether browning induced by clozapine can be explained by its known pharmacological effect of antagonizing serotonin (5HT) receptors, it was found that browning cells expressed 5HT receptors 2A, 1D, 7 and the upregulation of browning markers was diminished in the presence of exogenous 5HT. Undifferentiated progenitors or completely differentiated beige or white adipocytes did not respond to clozapine administration. The clozapine-induced beige cells displayed increased basal and oligomycin-inhibited (proton leak) oxygen consumption, but these cells showed a lower response to cAMP stimulus as compared with control beige adipocytes indicating that they are less capable to respond to natural thermogenic anti-obesity cues. Our data altogether suggest that novel pharmacological stimulation of these masked beige adipocytes can be a future therapeutic target for the treatment of SGA-induced weight gain.

Effect of hydrothermal dewatering on the slurryability of brown coals

International Nuclear Information System (INIS)

Yu Yujie; Liu Jianzhong; Wang Ruikun; Zhou Junhu; Cen Kefa

2012-01-01

Highlights: ► Brown coals are upgraded by hydrothermal dewatering. ► The moisture content and oxygen functional groups decrease during the process. ► The point of zero charge and the contact angle rise as the temperature increases. ► The products were highly hydrophobic. ► The improvement on slurryability of solid products were examined. - Abstract: Two brown coals from China were dewatered under hydrothermal dewatering (HTD) conditions at 250–320 °C for 1 h in a 2 L autoclave. The hydrothermally dewatered products were used to prepare coal water slurry (CWS) with a lower viscosity than brown raw coal slurry. Moreover, the coal rank and heat value of the brown coal increased as the inherent moisture and oxygen content decreased during the HTD process. The maximum solid concentration of CWS prepared from XiMeng coal increased from 45.7% to 59.3%, whereas that of CWS prepared from BaoTou coal increased from 53.7% to 62.1%, after being dewatered at 320 °C. The improvement in the slurryability of brown coal significantly depended on the final temperature of the HTD process, the mechanism of which can be explained by the chemical analysis of oxygen functional groups, zeta potential, and the contact angle of the surface between coal and water. The oxygen functional groups, the oxygen/carbon ratio and hydrogen/carbon ratio in brown coal decreased, indicating that the coal rank was upgraded during the HTD process. As a result, both the point of zero charge and the contact angle increased, implying that the HTD products were highly hydrophobic.

The feeding habits of brown hyaenas ( Hyaena brunnea ) on a game ...

African Journals Online (AJOL)

The feeding habits of brown hyaenas ( Hyaena brunnea ) on a game ranch in Limpopo Province, South Africa. ... brown hyaena Hyaena brunnea scats from a game ranch in the Limpopo Province, South Africa. ... AJOL African Journals Online.

Genomic evidence of geographically widespread effect of gene flow from polar bears into brown bears.

Science.gov (United States)

Cahill, James A; Stirling, Ian; Kistler, Logan; Salamzade, Rauf; Ersmark, Erik; Fulton, Tara L; Stiller, Mathias; Green, Richard E; Shapiro, Beth

2015-03-01

Polar bears are an arctic, marine adapted species that is closely related to brown bears. Genome analyses have shown that polar bears are distinct and genetically homogeneous in comparison to brown bears. However, these analyses have also revealed a remarkable episode of polar bear gene flow into the population of brown bears that colonized the Admiralty, Baranof and Chichagof islands (ABC islands) of Alaska. Here, we present an analysis of data from a large panel of polar bear and brown bear genomes that includes brown bears from the ABC islands, the Alaskan mainland and Europe. Our results provide clear evidence that gene flow between the two species had a geographically wide impact, with polar bear DNA found within the genomes of brown bears living both on the ABC islands and in the Alaskan mainland. Intriguingly, while brown bear genomes contain up to 8.8% polar bear ancestry, polar bear genomes appear to be devoid of brown bear ancestry, suggesting the presence of a barrier to gene flow in that direction. © 2014 The Authors. Molecular Ecology Published by John Wiley & Sons Ltd.

Organic contaminants in thermal plume resident brown trout

International Nuclear Information System (INIS)

Romberg, G.P.; Bourne, S.

1978-01-01

A pilot study was conducted to identify possible contaminants accumulated by thermal plume-resident fish in Lake Michigan. Brown trout were maintained in tanks receiving intake and discharge (less than or equal to 21 0 C) water from a power plant and were fed a diet of frozen alewife. Fish were sampled over a period of 127 days in order to estimate uptake rates and equilibrium levels for toxic organic and inorganic materials occurring in Lake Michigan fish and water. Experimental fish and natural samples were analyzed to determine the distribution of contaminants in various tissues and the corresponding pollutant levels in similar size brown trout from Lake Michigan. The quantitative analyses for the major organic contaminants are summarized. Without exception, the pyloric caecum of brown trout contained the highest concentration of lipids, PCB's, and chlorinated pesticides. Gill and kidney samples contained lower concentrations of contaminants than the caecum, while liver and muscle values were lowest

An unsuccessful search for brown dwarf companions to white dwarf stars

Science.gov (United States)

Shipman, Harry L.

1986-01-01

The results of a survey to detect excess infrared emission from white dwarf stars which would be attributable to a low mass companion are reviewed. Neither a simple comparison of spectroscopically identified white dwarf stars with the IRAS Point Source Catalog nor the coadding of IRAS survey data resulted in a detection of a brown dwarf. The seven nearest stars where the most stringent limits to the presence of a brown dwarf were obtained are listed, and an effort to detect brown dwarfs in the solar neighborhood is discussed.

LC-MS Untargeted Metabolomics To Explain the Signal Metabolites Inducing Browning in Fresh-Cut Lettuce.

Science.gov (United States)

García, Carlos J; García-Villalba, Rocío; Gil, María I; Tomas-Barberan, Francisco A

2017-06-07

Enzymatic browning is one of the main causes of quality loss in lettuce as a prepared and ready-to-eat cut salad. An untargeted metabolomics approach using UPLC-ESI-QTOF-MS was performed to explain the wound response of lettuce after cutting and to identify the metabolites responsible of browning. Two cultivars of Romaine lettuce with different browning susceptibilities were studied at short time intervals after cutting. From the total 5975 entities obtained from the raw data after alignment, filtration reduced the number of features to 2959, and the statistical analysis found that only 1132 entities were significantly different. Principal component analysis (PCA) clearly showed that these samples grouped according to cultivar and time after cutting. From those, only 15 metabolites belonging to lysophospholipids, oxylipin/jasmonate metabolites, and phenolic compounds were able to explain the browning process. These selected metabolites showed different trends after cutting; some decreased rapidly, others increased but decreased thereafter, whereas others increased during the whole period of storage. In general, the fast-browning cultivar showed a faster wound response and a higher raw intensity of some key metabolites than the slow-browning one. Just after cutting, the fast-browning cultivar contained 11 of the 15 browning-associated metabolites, whereas the slow-browning cultivar only had 5 of them. These metabolites could be used as biomarkers in breeding programs for the selection of lettuce cultivars with lower browning potential for fresh-cut applications.

Cleanup at Browns Ferry 3

International Nuclear Information System (INIS)

Mitchell, Brad; Janvrin, R.W.

1995-01-01

When major work had to be done in the drywell of Browns Ferry 3, the utility, Tennessee Valley Authority (TVA), decided that it made sense to make it ''street clothes clean'' for workers. This not only made work easier, it saved time and millions of dollars. (author)

Histone deacetylase 3 prepares brown adipose tissue for acute thermogenic challenge

DEFF Research Database (Denmark)

Emmett, Matthew J.; Lim, Hee-Woong; Jager, Jennifer

2017-01-01

Brown adipose tissue is a thermogenic organ that dissipates chemical energy as heat to protect animals against hypothermia and to counteract metabolic disease1. However, the transcriptional mechanisms that determine the thermogenic capacity of brown adipose tissue before environmental cold...

Apple phenolics and their contribution to enzymatic browning reactions

Directory of Open Access Journals (Sweden)

Wiesław Oleszek

2014-01-01

Full Text Available Chlorogenic acid, epicatechin, procyanidin B2 and C1 were isolated from apple skin. These compounds as well as quercetine and phloretine glycosides isolated from apples were studied individually and as mixtures for their participation in the enzymatic browning reactions. The importance of quercetine glycosides and the synergistic effect of phloridzin and phloretine xyloglucoside with chlorogenic acid and flavans in the browning reaction are reported.

Brown tumor of mandible with primary hyperparathyroidism

International Nuclear Information System (INIS)

Ali, S.K.; Khan, F.A.; Siddiq, A.; Hanif, M.S.

2011-01-01

Parathyroid hormone (PTH) is secreted and released by the parathyroid glands, the activity of which is controlled by the ionized serum calcium level. Increased PTH secretion results in hyperparathyroidism. Hyperparathyroidism is classified as primary, secondary and tertiary types. Primary hyperparathyroidism is characterized by increased parathyroid hormone secretion occurring as a result of abnormality in one or more of the parathyroid glands. Brown tumors are non-neoplastic lesions as a result of abnormal bone metabolism in cases of hyperparathyroidism, creating a local destructive phenomenon. A rare case of a young female patient with brown tumors in her mandible associated with primary hyperparathyroidism, is reported. (author)

Consortial brown tide - picocyanobacteria blooms in Guantánamo Bay, Cuba.

Science.gov (United States)

Hall, Nathan S; Litaker, R Wayne; Kenworthy, W Judson; Vandersea, Mark W; Sunda, William G; Reid, James P; Slone, Daniel H; Butler, Susan

2018-03-01

A brown tide bloom of Aureoumbra lagunensis developed in Guantánamo Bay, Cuba during a period of drought in 2013 that followed heavy winds and rainfall from Hurricane Sandy in late October 2012. Based on satellite images and water turbidity measurements, the bloom appeared to initiate in January 2013. The causative species (A. lagunensis) was confirmed by microscopic observation, and pigment and genetic analyses of bloom samples collected on May 28 of that year. During that time, A. lagunensis reached concentrations of 900,000 cells ml -1 (28 ppm by biovolume) in the middle portion of the Bay. Samples could not be collected from the northern (Cuban) half of the Bay because of political considerations. Subsequent sampling of the southern half of the Bay in November 2013, April 2014, and October 2014 showed persistent lower concentrations of A. lagunensis, with dominance shifting to the cyanobacterium Synechococcus (up to 33 ppm in April), an algal group that comprised a minor bloom component on May 28. Thus, unlike the brown tide bloom in Laguna Madre, which lasted 8 years, the bloom in Guantánamo Bay was short-lived, much like recent blooms in the Indian River, Florida. Although hypersaline conditions have been linked to brown tide development in the lagoons of Texas and Florida, observed euhaline conditions in Guantánamo Bay (salinity 35-36) indicate that strong hypersalinity is not a requirement for A. lagunensis bloom formation. Microzooplankton biomass dominated by ciliates was high during the observed peak of the brown tide, and ciliate abundance was high compared to other systems not impacted by brown tide. Preferential grazing by zooplankton on non-brown tide species, as shown in A. lagunensis blooms in Texas and Florida, may have been a factor in the development of the Cuban brown tide bloom. However, subsequent selection of microzooplankton capable of utilizing A. lagunensis as a primary food source may have contributed to the short-lived duration

Exploration of the brown dwarf regime around solar-like stars by CoRoT

OpenAIRE

Csizmadia, Szilárd

2016-01-01

Aims. A summary of the CoRoT brown dwarf investigations are presented. Methods. Transiting brown dwarfs around solar like stars were studied by using the photometric time-series of CoRoT, and ground based radial velocity measurements. Results. CoRoT detected three transiting brown dwarfs around F and G dwarf stars. The occurence rate of brown dwarfs was found to be 0.20 +/- 0.15% around solar-like stars which is compatible with the value obtained by Kepler-data.

Enzymatic oxalic acid regulation correlated with wood degradation in four brown-rot fungi

Science.gov (United States)

Anne Christine Steenkjær Hastrup; Frederick Green III; Patricia K. Lebow; Bo Jensen

2012-01-01

Oxalic acid is a key component in the initiation of brown-rot decay and it has been suggested that it plays multiple roles during the degradation process. Oxalic acid is accumulated to varying degrees among brown-rot fungi; however, details on active regulation are scarce. The accumulation of oxalic acid was measured in this study from wood degraded by the four brown-...

Role of ascorbic acid in the inhibition of polyphenol oxidase and the prevention of browning in different browning-sensitive Lactuca sativa var. capitata (L.) and Eruca sativa (Mill.) stored as fresh-cut produce.

Science.gov (United States)

Landi, Marco; Degl'Innocenti, Elena; Guglielminetti, Lorenzo; Guidi, Lucia

2013-06-01

Polyphenol oxidase (PPO) and, to a minor extent, peroxidase (POD) represent the key enzymes involved in enzymatic browning, a negative process induced by cutting fresh-cut produce such as lettuce (Lactuca sativa) and rocket salad (Eruca sativa). Although ascorbic acid is frequently utilised as an anti-browning agent, its mechanism in the prevention of the browning phenomenon is not clearly understood. The activity of PPO and POD and their isoforms in lettuce (a high-browning and low-ascorbic acid species) and rocket salad (a low-browning and high-ascorbic species) was characterised. The kinetic parameters of PPO and in vitro ascorbic acid-PPO inhibition were also investigated. In rocket salad, PPO activity was much lower than that in lettuce and cutting induced an increase in PPO activity only in lettuce. Exogenous ascorbic acid (5 mmol L(-1)) reduced PPO activity by about 90% in lettuce. POD did not appear to be closely related to browning in lettuce. PPO is the main enzyme involved in the browning phenomenon; POD appears to play a minor role. The concentration of endogenous ascorbic acid in rocket salad was related to its low-browning sensitivity after cutting. In lettuce, the addition of ascorbic acid directly inhibited PPO activity. The results suggest that the high ascorbic acid content found in rocket salad plays an effective role in reducing PPO activity. © 2012 Society of Chemical Industry.

Arctic Tundra Greening and Browning at Circumpolar and Regional Scales

Science.gov (United States)

Epstein, H. E.; Bhatt, U. S.; Walker, D. A.; Raynolds, M. K.; Yang, X.

2017-12-01

Remote sensing data have historically been used to assess the dynamics of arctic tundra vegetation. Until recently the scientific literature has largely described the "greening" of the Arctic; from a remote sensing perspective, an increase in the Normalized Difference Vegetation Index (NDVI), or a similar satellite-based vegetation index. Vegetation increases have been heterogeneous throughout the Arctic, and were reported to be up to 25% in certain areas over a 30-year timespan. However, more recently, arctic tundra vegetation dynamics have gotten more complex, with observations of more widespread tundra "browning" being reported. We used a combination of remote sensing data, including the Global Inventory Monitoring and Modeling System (GIMMS), as well as higher spatial resolution Landsat data, to evaluate the spatio-temporal patterns of arctic tundra vegetation dynamics (greening and browning) at circumpolar and regional scales over the past 3-4 decades. At the circumpolar scale, we focus on the spatial heterogeneity (by tundra subzone and continent) of tundra browning over the past 5-15 years, followed by a more recent recovery (greening since 2015). Landsat time series allow us to evaluate the landscape-scale heterogeneity of tundra greening and browning for northern Alaska and the Yamal Peninsula in northwestern Siberia, Russia. Multi-dataset analyses reveal that tundra greening and browning (i.e. increases or decreases in the NDVI respectively) are generated by different sets of processes. Tundra greening is largely a result of either climate warming, lengthening of the growing season, or responses to disturbances, such as fires, landslides, and freeze-thaw processes. Browning on the other hand tends to be more event-driven, such as the shorter-term decline in vegetation due to fire, insect defoliation, consumption by larger herbivores, or extreme weather events (e.g. winter warming or early summer frost damage). Browning can also be caused by local or

Controlled cellular energy conversion in brown adipose tissue thermogenesis

Science.gov (United States)

Horowitz, J. M.; Plant, R. E.

1978-01-01

Brown adipose tissue serves as a model system for nonshivering thermogenesis (NST) since a) it has as a primary physiological function the conversion of chemical energy to heat; and b) preliminary data from other tissues involved in NST (e.g., muscle) indicate that parallel mechanisms may be involved. Now that biochemical pathways have been proposed for brown fat thermogenesis, cellular models consistent with a thermodynamic representation can be formulated. Stated concisely, the thermogenic mechanism in a brown fat cell can be considered as an energy converter involving a sequence of cellular events controlled by signals over the autonomic nervous system. A thermodynamic description for NST is developed in terms of a nonisothermal system under steady-state conditions using network thermodynamics. Pathways simulated include mitochondrial ATP synthesis, a Na+/K+ membrane pump, and ionic diffusion through the adipocyte membrane.

Blood glucose lowering effects of brown rice in normal and diabetic subjects.

Science.gov (United States)

Panlasigui, Leonora N; Thompson, Lilian U

2006-01-01

Carbohydrate foods, which produce low glycemic responses, have been shown to be beneficial in the dietary management of chronic diseases such as diabetes and hyperlipidemia. This study determined the starch digestion rate in vitro and, in a randomised crossover design, the postprandial blood glucose response of 10 healthy and nine type 2 diabetic volunteers to brown rice compared to milled rice from the same batch and variety. The total sugar released in vitro was 23.7% lower in brown rice than in milled rice. In healthy volunteers, the glycemic area and glycemic index were, respectively, 19.8% and 12.1% lower (p brown rice than milled rice, while in diabetics, the respective values were 35.2% and 35.6% lower. The effect was partly due to the higher amounts of phytic acid, polyphenols, dietary fiber and oil in brown compared to milled rice and the difference in some physicochemical properties of the rice samples such as minimum cooking time and degree of gelatinisation. In conclusion, brown rice is a more health beneficial food for diabetics and hyperglycemic individuals than milled rice.

Utilization of a major brown rust resistance gene in sugarcane breeding

Science.gov (United States)

Brown rust, caused by Puccinia melanocephala has had devastating effects on sugarcane (Saccharum spp.) breeding programs and on commercial production. The discovery of Bru1, a major gene conferring resistance to brown rust represented a substantial breakthrough and markers for the detection of Bru1 ...

Brown Coal Dewatering Using Poly (Acrylamide-Co-Potassium Acrylic Based Super Absorbent Polymers

Directory of Open Access Journals (Sweden)

Sheila Devasahayam

2015-09-01

Full Text Available With the rising cost of energy and fuel oils, clean coal technologies will continue to play an important role during the transition to a clean energy future. Victorian brown coals have high oxygen and moisture contents and hence low calorific value. This paper presents an alternative non evaporative drying technology for high moisture brown coals based on osmotic dewatering. This involves contacting and mixing brown coal with anionic super absorbent polymers (SAP which are highly crossed linked synthetic co-polymers based on a cross-linked copolymer of acryl amide and potassium acrylate. The paper focuses on evaluating the water absorption potential of SAP in contact with 61% moisture Loy Yang brown coal, under varying SAP dosages for different contact times and conditions. The amount of water present in Loy Yang coal was reduced by approximately 57% during four hours of SAP contact. The extent of SAP brown coal drying is directly proportional to the SAP/coal weight ratio. It is observed that moisture content of fine brown coal can readily be reduced from about 59% to 38% in four hours at a 20% SAP/coal ratio.

The role of innate immunity in the regulation of brown and beige adipogenesis.

Science.gov (United States)

Alexaki, Vasileia Ismini; Chavakis, Triantafyllos

2016-03-01

The adipose tissue (AT) is multifunctional, acting as an endocrine tissue and participating in the regulation of the organism's homeostasis. Metabolic, endocrine and inflammatory mechanisms are tightly intertwined within the AT, regulating its function. Disruption of the equilibrium among these mechanisms leads to pathologies, the most common being obesity-related insulin resistance. Two types of AT exist, the white and the brown AT. Traditionally the white AT (WAT) was thought to store energy in the form of lipids, while the brown AT (BAT) was known to mediate heat generation. Recently, the 'brite' or 'beige' AT was identified, which is localized predominantly in subcutaneous WAT, but shares functional features with the BAT and is capable of heat production. The major stimulus triggering beige and brown adipogenesis is cold exposure and catecholamine signalling. However, several further signals and mechanisms exist, which can orchestrate and fine-tune beige and brown AT function. Immune cells and inflammation have emerged as regulators of beige and brown AT function. The present review will focus on the recently identified crosstalk between innate immunity and the regulation of beige and brown adipogenesis.

Genetic-industrial classification of brown coals in Serbia

Energy Technology Data Exchange (ETDEWEB)

Ercegovac, Marko [Serbian Academy of Sciences and Arts, Knez Mihailova 35, 11000 Belgrade (Serbia and Montenegro); ?ivotic, Dragana; Kostic, Aleksandar [University of Belgrade, Faculty of Mining and Geology, Djusina 7, 11000 Belgrade (Serbia and Montenegro)

2006-08-01

The petrologic, chemical and technological features of low-rank coals from nineteen of the most important basins in Serbia have been studied as part of the research project of genetic-industrial classification of low-rank coals of Serbia. Most of these features have been included as parameters of the codification system for low-rank coals. The paper discusses the main genetic, technological and supplementary parameters of the Serbian brown coals such as rank, petrographic composition, gelification degree, total moisture, ash content, sulphur content, calorific value, tar yield, the chemical composition and the thermotechnical properties of ash. The rank of brown coals from Serbia has been defined on the basis of the following parameters: random reflectance of huminite/vitrinite (R{sub r}=0.26-0.50%), total moisture (W{sup ar}=13.18-49.11%), gross calorific value (Q{sup daf}=22.3-29.2MJ/kg, dry, ash-free basis), net calorific value (Q{sup daf}=21.2-28.1MJ/kg, dry, ash-free basis). The results from the maceral analysis confirm that the humic coals, in general, are characterized by high huminite content (76.0-97.9vol.%, mineral matter free), low inertinite amount (0.7-6.3vol.%, mineral matter free), and a variable amount of liptinite (0.8-15.5vol.%, mineral matter free). It is possible to define three groups of Serbian brown coals on the basis of the primary, or genetic parameters, technological, or chemical parameters, and supplementary parameters: soft (Low-Rank C; [Economic Commission for Europe, Committee on Sustainable Energy- United Nations (ECE-UN), 1998. International Classification of in-Seam Coals. Energy 19, 41 pp.; Economic Commission for Europe, Committee on Sustainable Energy- United Nations (ECE-UN), 1999. International Codification System for Low-Rank Coals. Energy 9, 19 pp.; Economic Commission for Europe, Committee on Sustainable Energy- United Nations (ECE-UN), 2000. International Classification for Low-Rank Coals. Energy 12, 21 pp.]), dull (Low

Regulation of white and brown adipocyte differentiation by RhoGAP DLC1.

Directory of Open Access Journals (Sweden)

Choon Kiat Sim

Full Text Available Adipose tissues constitute an important component of metabolism, the dysfunction of which can cause obesity and type II diabetes. Here we show that differentiation of white and brown adipocytes requires Deleted in Liver Cancer 1 (DLC1, a Rho GTPase Activating Protein (RhoGAP previously studied for its function in liver cancer. We identified Dlc1 as a super-enhancer associated gene in both white and brown adipocytes through analyzing the genome-wide binding profiles of PPARγ, the master regulator of adipogenesis. We further observed that Dlc1 expression increases during differentiation, and knockdown of Dlc1 by siRNA in white adipocytes reduces the formation of lipid droplets and the expression of fat marker genes. Moreover, knockdown of Dlc1 in brown adipocytes reduces expression of brown fat-specific genes and diminishes mitochondrial respiration. Dlc1-/- knockout mouse embryonic fibroblasts show a complete inability to differentiate into adipocytes, but this phenotype can be rescued by inhibitors of Rho-associated kinase (ROCK and filamentous actin (F-actin, suggesting the involvement of Rho pathway in DLC1-regulated adipocyte differentiation. Furthermore, PPARγ binds to the promoter of Dlc1 gene to regulate its expression during both white and brown adipocyte differentiation. These results identify DLC1 as an activator of white and brown adipocyte differentiation, and provide a molecular link between PPARγ and Rho pathways.

Direct bioconversion of brown algae into ethanol by thermophilic bacterium Defluviitalea phaphyphila.

Science.gov (United States)

Ji, Shi-Qi; Wang, Bing; Lu, Ming; Li, Fu-Li

2016-01-01

Brown algae are promising feedstocks for biofuel production with inherent advantages of no structural lignin, high growth rate, and no competition for land and fresh water. However, it is difficult for one microorganism to convert all components of brown algae with different oxidoreduction potentials to ethanol. Defluviitalea phaphyphila Alg1 is the first characterized thermophilic bacterium capable of direct utilization of brown algae. Defluviitalea phaphyphila Alg1 can simultaneously utilize mannitol, glucose, and alginate to produce ethanol, and high ethanol yields of 0.47 g/g-mannitol, 0.44 g/g-glucose, and 0.3 g/g-alginate were obtained. A rational redox balance system under obligate anaerobic condition in fermenting brown algae was revealed in D. phaphyphila Alg1 through genome and redox analysis. The excess reducing equivalents produced from mannitol metabolism were equilibrated by oxidizing forces from alginate assimilation. Furthermore, D. phaphyphila Alg1 can directly utilize unpretreated kelp powder, and 10 g/L of ethanol was accumulated within 72 h with an ethanol yield of 0.25 g/g-kelp. Microscopic observation further demonstrated the deconstruction process of brown algae cell by D. phaphyphila Alg1. The integrated biomass deconstruction system of D. phaphyphila Alg1, as well as its high ethanol yield, provided us an excellent alternative for brown algae bioconversion at elevated temperature.

Production of the blood pressure lowing peptides from brown alga ( Undaria pinnatifida)

Science.gov (United States)

Minoru, Sato; Takashi, Oba; Takao, Hosokawa; Toshiyasu, Yamaguchi; Toshiki, Nakano; Tadao, Saito; Koji, Muramoto; Takashi, Kahara; Katsura, Funayama; Akio, Kobayashi; Takahisa, Nakano

2005-07-01

Brown alga ( Undaria pinnatifida) was treated with alginate lyase and hydrolyzed using 17 kinds of proteases and the inhibitory activity of the hydrolysates for the angiotensin-I-converting enzyme (ACE) was measured. Four hydrolysates with potent ACE-inhibitory activity were administered singly and orally to spontaneously hypertensive rats (SHRs). The systolic blood pressure of SHRs decreases significantly after single oral administration of the brown alga hydrolysates by protease S ‘Amano’ (from Bacillus stearothermophilus) at the concentration of 10 (mg protein) (kg body weight)-1. In the 17 weeks of feeding experiment, 7-week-old SHRs were fed standard diet supplemented with the brown alga hydrolysates for 10 weeks. In SHRs fed 1.0 and 0.1% brown alga hydrolysates, elevating of systolic bloodpressure was significantly suppressed for 7 weeks. To elucidate the active components, the brown alga hydrolysates were fractionated by 1-butanol extraction and HPLC on a reverse-phase column. Seven kinds of ACE-inhibitory peptides were isolated and identified by amino acid composition analysis, sequence analysis, and LC-MS with the results Val-Tyr, Ile-Tyr, Ala-Trp, Phe-Tyr, Val-Trp, Ile-Trp, and Leu-Trp. Each peptide was determined to have an antihypertensive effect after a single oral administration in SHRs. The brown alga hydrolysates were also confirmed to decrease the blood pressure in humans.

Black-Brown Relations and Stereotypes.

Science.gov (United States)

Mindiola, Tatcho Jr.; Niemann, Yolanda Flores; Rodriguez, Nestor

This book analyzes how African and Hispanic Americans perceive and interact with one another, highlighting black-brown relations in Houston, Texas, one of the largest cities with a majority ethnic population and one in which Hispanic Americans outnumber African Americans. Using results from several sociological studies, the book examines: how each…

Inhibition of tyrosinase-mediated enzymatic browning by sulfite and natural alternatives

NARCIS (Netherlands)

Kuijpers, T.F.M.; Vincken, J.P.

2013-01-01

Although sulfite is widely used to counteract enzymatic browning, its mechanism has remained largely unknown. We describe a double inhibitory mechanism of sulfite on enzymatic browning, affecting both the enzymatic oxidation of phenols into o‑quinones, as well as the non‑enzymatic

Monoterpene limonene induces brown fat-like phenotype in 3T3-L1 white adipocytes.

Science.gov (United States)

Lone, Jameel; Yun, Jong Won

2016-05-15

Several dietary compounds that are able to induce the brown fat-like phenotype in white adipocytes have been considered for treatment of obesity due to their ability to increase energy expenditure. Here, we report that limonene induces the brown fat-like phenotype in 3T3-L1 adipocytes by increasing expression of brown adipocyte-specific genes and proteins. Limonene-induced browning in white adipocytes was investigated by determining expression levels of brown fat-specific genes and proteins by real-time RT-PCR, immunoblot analysis, and immunocytochemical staining. Limonene enhanced mitochondrial biogenesis, as evidenced by increased mitochondrial content and immunofluorescent intensity. Limonene also significantly elevated protein levels of HSL, PLIN, p-AMPK, p-ACC, ACO, COX4, CPT1, and CYT C, suggesting its possible role in enhancement of lipolysis and lipid catabolism. Increased expression of PRDM16, UCP1, C/EBPβ, and other brown fat-specific markers by limonene was possibly mediated by activation of β3-adnergenic receptor (β3-AR), as inhibition of β3-AR inhibited up-regulation of brown fat-specific markers. Similarly, limonene-mediated activation of ERK and up-regulation of key brown adipocyte specific markers were eliminated by treatment with ERK antagonist. Taken together, these results suggest that limonene induces browning of 3T3-L1 adipocytes via activation of β3-AR and the ERK signaling pathway. In conclusion, our findings suggest that limonene plays a dual modulatory role in induction of the brown adipocyte-like phenotype as well as promotion of lipid metabolism and thus may have potential therapeutic implications for treatment of obesity. Copyright © 2016 Elsevier Inc. All rights reserved.

Population II brown dwarfs and dark haloes

International Nuclear Information System (INIS)

Zinnecker, H.

1986-01-01

Opacity-limited fragmentation is investigated as a function of the dust-to-gas ratio and it is found that the characteristic protostellar mass Msub(*) is metallicity-dependent. This dependence is such that, for the low metallicity gas out of which the stars of Population II formed in the halo, Msub(*) is less than 0.1 M solar mass. If applicable, these theoretical considerations would predict that substellar masses have formed more frequently under the metal-poor conditions in the early Galaxy (Population II brown dwarfs). Thus the missing mass in the Galactic halo and in the dark haloes around other spirals may well reside in these metal-poor Population II brown dwarfs. (author)

Utilization in rats of 14C-L-lysine-labeled casein browned by amino-carbonyl reaction

International Nuclear Information System (INIS)

Mori, Bunpei; Nakatsuji, Hirotaka.

1977-01-01

The investigation was carried out in order to elucidate the reason for the reduction in nutritive value of browned protein, by using labeled casein as a model protein. Goat casein preparation in which lysine residues had been labeled with 14 C was browned by amino-carbonyl reaction with glucose at 37 0 C. Browned or non-browned casein was ingested by growing rats by spaced feeding. When the rats ingested the browned casein the experimental group, higher radioactivity was found in TCA-soluble fraction in the small intestine as compared with that in the control group, while radioactivity was scarecely found in feces for 22 hr. Along with absorption delay, considerably high radioactivity was found in urine. The recovery of radioactivity in expired air of rats fed the labeled casein (browned and non-browned) was measured. In the experimental group, expired 14 CO 2 came out slower than the control group. From these results, it is suggested that the main reason for the reduction in nutritive value by browning reaction may be the formation of a lysine derivative in a protein, which remains in the small intestinal lumen as an absorption-delayed material and is finally excreted in urine. (auth.)

Multi-party quantum key agreement with five-qubit brown states

Science.gov (United States)

Cai, Tao; Jiang, Min; Cao, Gang

2018-05-01

In this paper, we propose a multi-party quantum key agreement protocol with five-qubit brown states and single-qubit measurements. Our multi-party protocol ensures each participant to contribute equally to the agreement key. Each party performs three single-qubit unitary operations on three qubits of each brown state. Finally, by measuring brown states and decoding the measurement results, all participants can negotiate a shared secret key without classical bits exchange between them. With the analysis of security, our protocol demonstrates that it can resist against both outsider and participant attacks. Compared with other schemes, it also possesses a higher information efficiency. In terms of physical operation, it requires single-qubit measurements only which weakens the hardware requirements of participant and has a better operating flexibility.

Development trends in the Lusatian brown coal mining industry

International Nuclear Information System (INIS)

Schwirten, D.

1994-01-01

Lusatia has lived on and with brown coal for over 200 years. Brown coal changed what was once a region in which forestry and agriculture predominated into an industrial region. Thanks to its good combustion properties and high energy yield brown coal very soon became known and popular. It was always the driving force for a rapid development which resulted in an economically sound and technically up-to-date industry in Lusatia. This powerful status of brown coal was however soon exploited for aims which were bound to lead to the downfall of two social structures (during the years from 1933 to 1990) by reason of a regime of unconditional autarchy. The economic and technical development thus initiated certainly brought many advantages, but it also had serious diadvantages. Constant increases in production, as a result of which planned rated outputs were intentionally disregarded, were the rule because production targets had to be met or exceeded. Economic inefficiency led to a scarcity of labour and a shortage of finances. Environmental aims had no priority since production was the absolute, primary objective. Consequently, this regime of economic autarchy ended in an one-way street as far as industry was concerned, a situation which was accompanied by an unexampled destruction of the natural basic living conditions and direct, threatening health hazards to man and nature. The year 1990 saw the beginning of the transition from planned controlled economy to free market economy. The reorganization of the former large combines as corporations was not however merely a formal change, but internally also represented a transformation. The brown coal mining industry manifested its new intention and determination to be economically competitive and unsubsidized in future, to operate in such a way as to be compatible with the environment and to exploit reserves carefully, as well as to render its activities socially compatible. (orig.) [de

Database for content of mercury in Polish brown coal

Science.gov (United States)

Jastrząb, Krzysztof

2018-01-01

Poland is rated among the countries with largest level of mercury emission in Europe. According to information provided by the National Centre for Balancing and Management of Emissions (KOBiZE) more than 10.5 tons of mercury and its compounds were emitted into the atmosphere in 2015 from the area of Poland. Within the scope of the BazaHg project lasting from 2014 to 2015 and co-financed from the National Centre of Research and Development (NCBiR) a database was set up with specification of mercury content in Polish hard steam coal, coking coal and brown coal (lignite) grades. With regard to domestic brown coal the database comprises information on coal grades from Brown Coal Mines of `Bełchatów', `Adamów', `Turów' and `Sieniawa'. Currently the database contains 130 records with parameters of brown coal, where each record stands for technical analysis (content of moisture, ash and volatile particles), elemental analysis (CHNS), content of chlorine and mercury as well as net calorific value and combustion heat. Content of mercury in samples of brown coal grades under test ranged from 44 to 985 μg of Hg/kg with the average level of 345 μg of Hg/kg. The established database makes up a reliable and trustworthy source of information about content of mercury in Polish fossils. The foregoing details completed with information about consumption of coal by individual electric power stations and multiplied by appropriate emission coefficients may serve as the background to establish loads of mercury emitted into atmosphere from individual stations and by the entire sector of power engineering in total. It will also enable Polish central organizations and individual business entities to implement reasonable policy with respect of mercury emission into atmosphere.

Molecular phylogeography of the brown bear (Ursus arctos) in Northeastern Asia based on analyses of complete mitochondrial DNA sequences.

Science.gov (United States)

Hirata, Daisuke; Mano, Tsutomu; Abramov, Alexei V; Baryshnikov, Gennady F; Kosintsev, Pavel A; Vorobiev, Alexandr A; Raichev, Evgeny G; Tsunoda, Hiroshi; Kaneko, Yayoi; Murata, Koichi; Fukui, Daisuke; Masuda, Ryuichi

2013-07-01

To further elucidate the migration history of the brown bears (Ursus arctos) on Hokkaido Island, Japan, we analyzed the complete mitochondrial DNA (mtDNA) sequences of 35 brown bears from Hokkaido, the southern Kuril Islands (Etorofu and Kunashiri), Sakhalin Island, and the Eurasian Continent (continental Russia, Bulgaria, and Tibet), and those of four polar bears. Based on these sequences, we reconstructed the maternal phylogeny of the brown bear and estimated divergence times to investigate the timing of brown bear migrations, especially in northeastern Eurasia. Our gene tree showed the mtDNA haplotypes of all 73 brown and polar bears to be divided into eight divergent lineages. The brown bear on Hokkaido was divided into three lineages (central, eastern, and southern). The Sakhalin brown bear grouped with eastern European and western Alaskan brown bears. Etorofu and Kunashiri brown bears were closely related to eastern Hokkaido brown bears and could have diverged from the eastern Hokkaido lineage after formation of the channel between Hokkaido and the southern Kuril Islands. Tibetan brown bears diverged early in the eastern lineage. Southern Hokkaido brown bears were closely related to North American brown bears.

SMA and CARMA observations of young brown dwarfs in ρ Ophiuchi and Taurus

Directory of Open Access Journals (Sweden)

Lee C.-F.

2011-07-01

Full Text Available Molecular outflows provide vital information about the earliest stages in the birth of stars, studying the molecular outflow properties is therefore crucial for understanding how stars form. Brown dwarfs with masses between that of stars and planets are not massive enough to maintain stable hydrogen-burning fusion reactions during most of their lifetime. Their origins are subject to much debate in recent literature because their masses are far below the typical mass where core collapse is expected to occur. Based on Submillimeter Array (SMA and Combined Array for Research in Millimeter-wave Astronomy (CARMA observations, we present the first detections of bipolar molecular outflows from young brown dwarfs in ρ Ophiuchi and Taurus. Our results demonstrate that the bipolar molecular outflow operates down to brown dwarf masses, occurring in brown dwarfs as a scaled-down version of the universal process seen in young low-mass stars. This demonstrates that brown dwarfs and low-mass stars likely share the same formation mechanism.

The physiological basis of the migration continuum in brown trout ( Salmo trutta)

DEFF Research Database (Denmark)

Boel, Mikkel; Aarestrup, Kim; Baktoft, Henrik

2014-01-01

Partial migration is common in many animal taxa; however, the physiological variation underpinning migration strategies remains poorly understood. Among salmonid fishes, brown trout (Salmo trutta) is one of the species that exhibits the most complex variation in sympatric migration strategies......, expressed as a migration continuum, ranging from residency to anadromy. In looking at brown trout, our objective with this study was to test the hypothesis that variation in migration strategies is underpinned by physiological variation. Prior to migration, physiological samples were taken from fish...... in brown trout....

An historical perspective - Brown is not a color. [astrophysics of infrared dwarf stars

Science.gov (United States)

Tarter, J. C.

1986-01-01

Major shifts in theoretical understanding of the star formation process and the possible components of the local mass density are reviewed. Those aspects of brown dwarf structure and evolution that are still not well enough understood are outlined, and the types of observations that might force the modification of current theories to accommodate the existence of brown dwarfs are suggested. The appropriateness of the name 'brown dwarf' is defended.

Genetic characterization of Kenai brown bears (Ursus arctos): Microsatellite and mitochondrial DNA control region variation in brown bears of the Kenai Peninsula, south central Alaska

Science.gov (United States)

Jackson, J.V.; Talbot, S.L.; Farley, S.

2008-01-01

We collected data from 20 biparentally inherited microsatellite loci, and nucleotide sequence from the maternally inherited mitochondrial DNA (mtDNA) control region, to determine levels of genetic variation of the brown bears (Ursus arctos L., 1758) of the Kenai Peninsula, south central Alaska. Nuclear genetic variation was similar to that observed in other Alaskan peninsular populations. We detected no significant inbreeding and found no evidence of population substructuring on the Kenai Peninsula. We observed a genetic signature of a bottleneck under the infinite alleles model (IAM), but not under the stepwise mutation model (SMM) or the two-phase model (TPM) of microsatellite mutation. Kenai brown bears have lower levels of mtDNA haplotypic diversity relative to most other brown bear populations in Alaska. ?? 2008 NRC.

The Effect of Irradiation Treatment on the Non-Enzymatic Browning Reaction in Legume Seeds

International Nuclear Information System (INIS)

El-Niely, H.F.G.

2013-01-01

The present study was conducted to evaluate the effects of gamma irradiation treatment, at room temperature, on the non-enzymatic browning reaction (Millerd reaction products, MRPs) generated in soybeans, broad beans and dried peas seeds at dose levels of 10, 30 and 60 kGy and their effects on the chemical constituents, soluble protein, available lysine and in vitro protein digestibility. The formation of MRPs in the studied legumes was assayed by monitoring the formation of brown pigments (browning intensity) by spectrophotometric method. The results revealed that the chemical composition of irradiated legumes showed non-significant differences relative to the raw one. A dose dependent decrease in soluble proteins and available lysine in the three legumes were observed. The non-enzymatic browning reaction was significantly increased with increasing the radiation dose, which was proved by changes in browning index tests. At the same time, the in vitro protein digestibility was increased after irradiation up to 60 kGy. Irradiation of dried peas with 60 kGy produced higher browning index than the other legumes. A positive correlation was observed between the radiation dose and the browning index for soybeans (R2= 0.96), broad beans (R2 = 0.81) and dried peas (R2 = 0.97) which means that 96%, 81% and 97 of the variation in the incidence of non-enzymatic browning reaction in soybean, broad bean and dried peas, respectively, are due to the effect of irradiation treatments. The present study suggests that the formation of non-enzymatic browning reaction did not impair the nutritional quality of legumes, therefore, the process of irradiation was helpful in increasing the in vitro protein digestibility of studied legumes. These results clearly indicated that gamma irradiation processing at the studied doses can add valuable effects to the studied legumes

Maxillary brown tumor associated with chronic kidney failure: a case report

Directory of Open Access Journals (Sweden)

Stênio Medeiros Queiroz

2013-12-01

Full Text Available The brown tumor is a bone lesion that may affect the entire skeleton, including the maxillary bones. These tumors are characterized as focal giant cell lesions that may be associated with primary or secondary hyperparathyroidism (HPT. Brown tumors are invasive in some cases and an association with chronic renal failure (CRF has been reported. With the aim to facilitate the differential diagnosis of bone lesions that may affect dialysis patients, this paper describes a case of brown tumor in a 36- year old patient with CRF, secondary HPT carrier, who had a lesion on the right maxilla for approximately five months.

Brown-McLean Syndrome in a Pediatric Patient

Science.gov (United States)

Tourkmani, Abdo Karim; Martinez, Jaime D.; Berrones, David; Juárez-Domínguez, Brenda Y.; Beltrán, Francisco; Galor, Anat

2015-01-01

The purpose of this manuscript is to report the case of a 12-year-old patient who presented for routine ophthalmic examination after congenital cataract surgery performed at 2 months of age. The patient was diagnosed with bilateral Brown-McLean syndrome by slit lamp examination. No treatment was required because the patient was asymptomatic and had a clear central cornea. This is the first described case of Brown-McLean syndrome in a pediatric patient, representing the importance of clinical examination in the pediatric age group after cataract surgery because of the risk for patients of developing peripheral edema. PMID:26034485

Tribbles 3 inhibits brown adipocyte differentiation and function by suppressing insulin signaling

Energy Technology Data Exchange (ETDEWEB)

Jeong, Ha-Won; Choi, Ran Hee; McClellan, Jamie L. [Division of Applied Physiology, Department of Exercise Science, University of South Carolina, Columbia, SC 29208 (United States); Piroli, Gerardo G.; Frizzell, Norma [Department of Pharmacology, Physiology & Neuroscience, University of South Carolina School of Medicine, Columbia, SC 29208 (United States); Tseng, Yu-Hua; Goodyear, Laurie J. [Research Division, Joslin Diabetes Center and Department of Medicine, Harvard Medical School, Boston, MA 02215 (United States); Koh, Ho-Jin, E-mail: kohh@mailbox.sc.edu [Division of Applied Physiology, Department of Exercise Science, University of South Carolina, Columbia, SC 29208 (United States)

2016-02-19

Recent studies have demonstrated that adult humans have substantial amounts of functioning brown adipose tissue (BAT). Since BAT has been implicated as an anti-obese and anti-diabetic tissue, it is important to understand the signaling molecules that regulate BAT function. There has been a link between insulin signaling and BAT metabolism as deletion or pharmaceutical inhibition of insulin signaling impairs BAT differentiation and function. Tribbles 3 (TRB3) is a pseudo kinase that has been shown to regulate metabolism and insulin signaling in multiple tissues but the role of TRB3 in BAT has not been studied. In this study, we found that TRB3 expression was present in BAT and overexpression of TRB3 in brown preadipocytes impaired differentiation and decreased expression of BAT markers. Furthermore, TRB3 overexpression resulted in significantly lower oxygen consumption rates for basal and proton leakage, indicating decreased BAT activity. Based on previous studies showing that deletion or pharmaceutical inhibition of insulin signaling impairs BAT differentiation and function, we assessed insulin signaling in brown preadipocytes and BAT in vivo. Overexpression of TRB3 in cells impaired insulin-stimulated IRS1 and Akt phosphorylation, whereas TRB3KO mice displayed improved IRS1 and Akt phosphorylation. Finally, deletion of IRS1 abolished the function of TRB3 to regulate BAT differentiation and metabolism. These data demonstrate that TRB3 inhibits insulin signaling in BAT, resulting in impaired differentiation and function. - Highlights: • TRB3 is expressed in brown adipose tissue and its expression is increased during differentiation. • Overexpression of TRB3 inhibits differentiation and its activity. • Overexpression of TRB3 in brown preadipocytes inhibits insulin signaling. • TRB3KO mice displays improved insulin signaling in brown adipose tissue. • Insulin signaling is required for the effects of TRB3 to regulate brown adipose tissue differentiation and

Tribbles 3 inhibits brown adipocyte differentiation and function by suppressing insulin signaling

International Nuclear Information System (INIS)

Jeong, Ha-Won; Choi, Ran Hee; McClellan, Jamie L.; Piroli, Gerardo G.; Frizzell, Norma; Tseng, Yu-Hua; Goodyear, Laurie J.; Koh, Ho-Jin

2016-01-01

Recent studies have demonstrated that adult humans have substantial amounts of functioning brown adipose tissue (BAT). Since BAT has been implicated as an anti-obese and anti-diabetic tissue, it is important to understand the signaling molecules that regulate BAT function. There has been a link between insulin signaling and BAT metabolism as deletion or pharmaceutical inhibition of insulin signaling impairs BAT differentiation and function. Tribbles 3 (TRB3) is a pseudo kinase that has been shown to regulate metabolism and insulin signaling in multiple tissues but the role of TRB3 in BAT has not been studied. In this study, we found that TRB3 expression was present in BAT and overexpression of TRB3 in brown preadipocytes impaired differentiation and decreased expression of BAT markers. Furthermore, TRB3 overexpression resulted in significantly lower oxygen consumption rates for basal and proton leakage, indicating decreased BAT activity. Based on previous studies showing that deletion or pharmaceutical inhibition of insulin signaling impairs BAT differentiation and function, we assessed insulin signaling in brown preadipocytes and BAT in vivo. Overexpression of TRB3 in cells impaired insulin-stimulated IRS1 and Akt phosphorylation, whereas TRB3KO mice displayed improved IRS1 and Akt phosphorylation. Finally, deletion of IRS1 abolished the function of TRB3 to regulate BAT differentiation and metabolism. These data demonstrate that TRB3 inhibits insulin signaling in BAT, resulting in impaired differentiation and function. - Highlights: • TRB3 is expressed in brown adipose tissue and its expression is increased during differentiation. • Overexpression of TRB3 inhibits differentiation and its activity. • Overexpression of TRB3 in brown preadipocytes inhibits insulin signaling. • TRB3KO mice displays improved insulin signaling in brown adipose tissue. • Insulin signaling is required for the effects of TRB3 to regulate brown adipose tissue differentiation and

Conservation implications of brown hyaena (Parahyaena brunnea population densities and distribution across landscapes in Botswana

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Christiaan W. Winterbach

2017-05-01

Full Text Available The brown hyaena (Parahyaena brunnea is endemic to southern Africa. The largest population of this near-threatened species occurs in Botswana, but limited data were available to assess distribution and density. Our objectives were to use a stratified approach to collate available data and to collect more data to assess brown hyaena distribution and density across land uses in Botswana. We conducted surveys using track counts, camera traps and questionnaires and collated our results and available data to estimate the brown hyaena population based on the stratification of Botswana for large carnivores. Brown hyaenas occur over 533 050 km² (92% of Botswana. Our density estimates ranged from 0 brown hyaenas/100 km² in strata of northern Botswana to 2.94 (2.16–3.71 brown hyaenas/100 km² in the southern stratum of the Central Kalahari Game Reserve. We made assumptions regarding densities in strata that lacked data, using the best references available. We estimated the brown hyaena population in Botswana as 4642 (3133–5993 animals, with 6.8% of the population in the Northern Conservation Zone, 73.1% in the Southern Conservation Zone, 2.0% in the smaller conservation zones and 18.1% in the agricultural zones. The similar densities of brown hyaenas in the Central Kalahari Game Reserve and the Ghanzi farms highlight the potential of agricultural areas in Botswana to conserve this species. The conservation of brown hyaenas in the agricultural landscape of Botswana is critical for the long-term conservation of the species; these areas provide important links between populations in South Africa, Namibia and Zimbabwe. Conservation implications: Botswana contains the core of the brown hyaena population in southern Africa, and conflict mitigation on agricultural land is crucial to maintaining connectivity among the range countries.

iTRAQ-Based Quantitative Proteomics Identifies Potential Regulatory Proteins Involved in Chicken Eggshell Brownness.

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Guangqi Li

Full Text Available Brown eggs are popular in many countries and consumers regard eggshell brownness as an important indicator of egg quality. However, the potential regulatory proteins and detailed molecular mechanisms regulating eggshell brownness have yet to be clearly defined. In the present study, we performed quantitative proteomics analysis with iTRAQ technology in the shell gland epithelium of hens laying dark and light brown eggs to investigate the candidate proteins and molecular mechanisms underlying variation in chicken eggshell brownness. The results indicated 147 differentially expressed proteins between these two groups, among which 65 and 82 proteins were significantly up-regulated in the light and dark groups, respectively. Functional analysis indicated that in the light group, the down-regulated iron-sulfur cluster assembly protein (Iba57 would decrease the synthesis of protoporphyrin IX; furthermore, the up-regulated protein solute carrier family 25 (mitochondrial carrier; adenine nucleotide translocator, member 5 (SLC25A5 and down-regulated translocator protein (TSPO would lead to increased amounts of protoporphyrin IX transported into the mitochondria matrix to form heme with iron, which is supplied by ovotransferrin protein (TF. In other words, chickens from the light group produce less protoporphyrin IX, which is mainly used for heme synthesis. Therefore, the exported protoporphyrin IX available for eggshell deposition and brownness is reduced in the light group. The current study provides valuable information to elucidate variation of chicken eggshell brownness, and demonstrates the feasibility and sensitivity of iTRAQ-based quantitative proteomics analysis in providing useful insights into the molecular mechanisms underlying brown eggshell pigmentation.

Pre-migratory differentiation of wild brown trout into migrant and resident individuals

DEFF Research Database (Denmark)

Nielsen, C.; Aarestrup, Kim; Norum, U.

2003-01-01

In February to March, wild brown trout Salmo trutta were captured by electrofishing in a natural watercourse (tributaries of the River Lille Aa, Denmark), individually tagged (Passive Integrated Transponders), and released. Representatives of the tagged brown trout were recaptured on the release......+,K+-ATPase analysis. Based on repetitive gill enzyme analysis in individual fish, a retrospective analysis of the rate of development in individual brown trout ultimately classified as migrants or residents was performed. Two months prior to migration, a bimodal morphological and physiological (gill Na...... a smolt-like appearance before the onset of migration and had higher rate of change of gill Na+,K+-ATPase activity than fish remaining residents. The rate of change of gill Na+,K+-ATPase activity was independent of the distance migrated to the trap (3-28 km). Thus in bimodal wild brown trout populations...

Invasive Brown Treesnake movements at road edges indicate road-crossing avoidance

Science.gov (United States)

Siers, Shane R.; Savidge, Julie S; Reed, Robert N.

2014-01-01

Roads have significant impacts on the dispersal of wildlife. Although this poses a threat to the abundance and diversity of desirable flora and fauna, it also affords some opportunity for enhancing control of invasive species. Roads are the most common terrain features that may affect the rate of landscape-scale movements of invasive Brown Treesnakes (Boiga irregularis) throughout Guam. We radio tracked 45 free-ranging Brown Treesnakes in close proximity to two roads in Guam and recorded instances where daily relocations of snakes spanned roads. Then we reconstructed observed movement histories with randomized turning angles, which served as a useful null hypothesis for assessing the effect of roads or road edge habitat on Brown Treesnake movement patterns. Random walk simulations demonstrated that Brown Treesnakes crossed these roads at a rate far lower than would be expected if snake movement was random with respect to roads and road edge habitat. We discuss two alternative hypotheses for these results: 1) habitat gaps posed by roads physically or behaviorally restrict snake movement; or 2) road edges provide preferred foraging habitat from which snakes are reluctant to depart. Because roads often form the boundaries of jurisdictional and management units, the effects of roads on the movement of invasive Brown Treesnakes will influence the prospects for success of future landscape-level suppression efforts.

Influence of small hydropower plants on brown trout (Salmo trutta L. population in Mislinja River

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Blaž Cokan

2013-12-01

Full Text Available The brown trout (Salmo trutta L. in the Mislinja River has been endangered for years because of small hydroelectric power plants. To find out how they are affecting the population of the brown trout in the Mislinja River, we conducted a sampling of the brown trout, using a generating set. We measured the length and weight of all caught specimens and analysed the obtained data. The results are presented in this paper, e.g., biomass, estimations of abundance, average weight, average length and number of captured brown trout. We discovered that the population of the brown trout has decreased in all the sections where water has been taken away for small hydroelectric power plants.

Population-level resource selection by sympatric brown and American black bears in Alaska

Science.gov (United States)

Belant, Jerrold L.; Griffith, Brad; Zhang, Yingte; Follmann, Erich H.; Adams, Layne G.

2010-01-01

Distribution theory predicts that for two species living in sympatry, the subordinate species would be constrained from using the most suitable resources (e.g., habitat), resulting in its use of less suitable habitat and spatial segregation between species. We used negative binomial generalized linear mixed models with fixed effects to estimate seasonal population-level resource selection at two spatial resolutions for female brown bears (Ursus arctos) and female American black bears (U. americanus) in southcentral Alaska during May–September 2000. Black bears selected areas occupied by brown bears during spring which may be related to spatially restricted (i.e., restricted to low elevations) but dispersed or patchy availability of food. In contrast, black bears avoided areas occupied by brown bears during summer. Brown bears selected areas near salmon streams during summer, presumably to access spawning salmon. Use of areas with high berry production by black bears during summer appeared in response to avoidance of areas containing brown bears. Berries likely provided black bears a less nutritious, but adequate food source. We suggest that during summer, black bears were displaced by brown bears, which supports distribution theory in that black bears appeared to be partially constrained from areas containing salmon, resulting in their use of areas containing less nutritious forage. Spatial segregation of brown and American black bears apparently occurs when high-quality resources are spatially restricted and alternate resources are available to the subordinate species. This and previous work suggest that individual interactions between species can result in seasonal population-level responses.

Radiocaesium turnover in Arctic charr (Salvelinus alpinus) and brown trout (Salmo trutta) in a Norwegian lake

International Nuclear Information System (INIS)

Forseth, T.; Ugedal, O.; Jonsson, B.; Langeland, A.; Njaastad, O.

1991-01-01

The radioactivity of brown trout (Salmo trutta L.) and Arctic charr (Salvelinus alpinus (L.)) was monitored in a Norwegian lake from 1986 to 1989. A distinct difference was observed between brown trout and Arctic charr in the accumulation of radiocaesium ( 134 Cs and 137 Cs) from the Chernobyl fallout, and the study focused on the understanding of this difference. Brown trout had a large food consumption and a corresponding high intake of radiocaesium. Excretion was 20% faster in brown trout than Arctic charr as brown trout lived at high temperatures in epilimnic water. Arctic charr had a lower food consumption (less than one-third of trout) and lived in colder meta-and hypolimnic water. Arctic charr therefore had a lower intake and slower excretion of radiocaesium. Brown trout an Arctic charr had different diets. For brown trout zoobenthos was the dominant food item, whereas Artic charr mainly fed on zooplankton. The radioactivity in the stomach contents of the two species was different in 1986, but similar for the rest of the period. Higher levels of radiocaesium in brown trout than Arctic charr in 1986 were due to a higher food consumption and more radioactive food items in its diet. The parallel development in accumulated radiocaesium through summer 1987 was probably formed by brown trout balancing a higher intake with a faster excretion. The ecological half-lives of radiocaesium in brown trout (357 days) and Arctic charr (550 days) from Lake Hoeysjoeen indicated a slow removal of the isotopes from the food webs. (author)

An unusual presentation of Brown-Sequard syndrome.

Science.gov (United States)

Herr, R D; Barrett, J

1987-11-01

We report the case of a man with Brown-Sequard syndrome following a fall in which he sustained fractures of the thoracic and lumbosacral spine. Despite characteristic neurological findings, the diagnosis was delayed due to the absence of history of penetrating spinal trauma and incorrect attribution of unilateral-like weakness and numbness to lumbosacral trauma. A directed history and examination revealed that the patient was stabbed in the back with a penknife while leaving a bus and stepped down onto a paralyzed leg, which collapsed beneath him. The patient was given an antibiotic, underwent a negative peritoneal lavage, and had myelography and nerve conduction velocity confirmatory for Brown-Sequard syndrome. With rehabilitation he became ambulatory with a cane one month after the stabbing.

[Cancer cachexia and white adipose tissue browning].

Science.gov (United States)

Zhang, S T; Yang, H M

2016-08-01

Cancer cachexia occurs in a majority of advanced cancer patients. These patients with impaired physical function are unable to tolerance cancer treatment well and have a significantly reduced survival rate. Currently, there is no effective clinical treatment available for cancer cachexia, therefore, it is necessary to clarify the molecular mechanisms of cancer cachexia, moreover, new therapeutic targets for cancer cachexia treatment are urgently needed. Very recent studies suggest that, during cancer cachexia, white adipose tissue undergo a 'browning' process, resulting in increased lipid mobilization and energy expenditure, which may be necessary for the occurrence of cancer cachexia. In this article, we summarize the definition and characteristics of cancer cachexia and adipose tissue 'browning', then, we discuss the new study directions presented in latest research.

A rare complication of secondary hyperparathyroidism: Brown tumor of the maxilla and mandible

International Nuclear Information System (INIS)

Sumer, Pinar A.; Sumer, Mahmut; Arik, Nurol; Karogoz, Filiz

2004-01-01

Brown tumors are focal bone lesions caused by increased osteoclastic activity and fibroblastic proliferation encountered in primary or more rarely secondary hyperparathyroidism. Ninety-two percent of the patients undergoing dialysis develop secondary hyperparathyroidism. Of these, approximately 1.5% develops brown tumors. Brown tumors of hyperparathyroidism may appear in any bone but are frequently found in the facial bones and jaws, particularly in long-standing cases of the disease. As it becomes common for hyperparathyroidism to be detected earlier during the disease, the bony manifestations of the disease are rarely seen. The following report describes a case of brown tumor of the maxilla and mandible in a patient with renal insufficiency. This patient presented multiple skeletal lesions, which are uncommonly seen now a days. (author)

Consortial brown tide − picocyanobacteria blooms in Guantánamo Bay, Cuba

Science.gov (United States)

Hall, Nathan S; Litaker, R. Wayne; Kenworthy, W. Judson; Vandersea, Mark W.; Sunda, William G.; Reid, James P.; Slone, Daniel H.; Butler, Susan M.

2018-01-01

A brown tide bloom of Aureoumbra lagunensis developed in Guantánamo Bay, Cuba during a period of drought in 2013 that followed heavy winds and rainfall from Hurricane Sandy in late October 2012. Based on satellite images and water turbidity measurements, the bloom appeared to initiate in January 2013. The causative species (A. lagunensis) was confirmed by microscopic observation, and pigment and genetic analyses of bloom samples collected on May 28 of that year. During that time, A. lagunensis reached concentrations of 900,000 cells ml−1 (28 ppm by biovolume) in the middle portion of the Bay. Samples could not be collected from the northern (Cuban) half of the Bay because of political considerations. Subsequent sampling of the southern half of the Bay in November 2013, April 2014, and October 2014 showed persistent lower concentrations of A. lagunensis, with dominance shifting to the cyanobacterium Synechococcus (up to 33 ppm in April), an algal group that comprised a minor bloom component on May 28. Thus, unlike the brown tide bloom in Laguna Madre, which lasted 8 years, the bloom in Guantánamo Bay was short-lived, much like recent blooms in the Indian River, Florida. Although hypersaline conditions have been linked to brown tide development in the lagoons of Texas and Florida, observed euhaline conditions in Guantánamo Bay (salinity 35–36) indicate that strong hypersalinity is not a requirement for A. lagunensis bloom formation. Microzooplankton biomass dominated by ciliates was high during the observed peak of the brown tide, and ciliate abundance was high compared to other systems not impacted by brown tide. Preferential grazing by zooplankton on non-brown tide species, as shown in A. lagunensis blooms in Texas and Florida, may have been a factor in the development of the Cuban brown tide bloom. However, subsequent selection of microzooplankton capable of utilizing A. lagunensis as a primary food source may have contributed to the

"'Look More Closely,' Said Mum": Mothers in Anthony Browne's Picture Books

Science.gov (United States)

Joosen, Vanessa

2015-01-01

In this article, Vanessa Joosen explores Anthony Browne's construction of motherhood in four of his picture books that focus on family. She focuses on the use of narratological perspective, visual point of view, and intertextual references to explain how an ideology of motherhood is evoked. While Browne makes use of child narrators and focalizers…

An environmental DNA marker for detecting nonnative brown trout (Salmo trutta)

Science.gov (United States)

K. J. Carim; T. M. Wilcox; M. Anderson; D. Lawrence; Michael Young; Kevin McKelvey; Michael Schwartz

2016-01-01

Brown trout (Salmo trutta) are widely introduced in western North America where their presence has led to declines of several native species. To assist conservation efforts aimed at early detection and eradication of this species, we developed a quantitative PCR marker to detect the presence of brown trout DNA in environmental samples. The marker strongly...

Assessment of the radiation risk following from exploitation of Polish brown coals. Part 1. Brown coal in Polish industry; preparation of the method of determining the concentrations of main natural radioisotopes appearing in brown coal and its combustion products

International Nuclear Information System (INIS)

Jasinska, M.; Niewiadomski, T.; Schwabenthan, J.

1982-01-01

Poland is rich in deposits of brown coal applicable for large-scale industry. These deposits are estimated at about 13.5.10 9 tons. In the near future, one-half of the electric power produced in Poland will be generated by power plants using brown coal. As a result, the yearly burden of the environment in Poland will amount to about 15.10 6 tons of ashes and slag, and about 0.79.10 6 tons of fly ash emitted into the atmosphere. Concentrations of radioactive elements in wastes following from the use of brown coal may in some cases be as much as 12 times higher that occuring from combustion products of lignite coal. Distribution of these wastes to the environment affects the population, through inhalation of fly-ashes, consumption of radioactively contaminated products and through living in dwellings constructed of building materials produced using industrial wastes. In order to determine the concentrations of 226 Ra, 232 Th and 40 K in brown coal and in products of its combustion, the method of identifying these elements through gamma-spectrometry has been prepared. Concentrations of 210 Pb and 210 Po will be determined using the method of electrodeposition on metallic silver, which has been tested in the laboratory. (author)

Síndrome de Brown bilateral associada com hipermobilidade articular benigna: relato de caso Bilateral Brown's syndrome associated with benign joint hypermobility: a case report

Directory of Open Access Journals (Sweden)

David Kirsch

2007-03-01

Full Text Available A síndrome de Brown é caracterizada por grande limitação de elevação em adução, elevação ligeiramente diminuída ou normal na abdução, anisotropia em "Y" ou "V", intorção do olho em supraversão e ducção forçada positiva. Sua causa se deve à inelastibilidade do músculo oblíquo superior ou por sua contenção em sua própria bainha. A hipermobilidade articular benigna é doença hereditária do tecido conectivo caracterizada por aumento da mobilidade em diversas articulações. Sua prevalência é muito variável em relação à idade, sexo e etnia, variando de 2 a 35% em homens e de 5 a 57% e mulheres. Neste relato os autores descrevem um caso de síndrome de Brown associada com hipermobilidade articular benigna e atentam para a associação pouco referida na literatura. J.C.S, masculino, 6 anos de idade, pardo, estudante, foi encaminhado à Universidade de Santo Amaro com queixa de exotropia há dois anos que aumentava na supraversão. Paciente com o diagnóstico de síndrome de Brown bilateral teve o diagnóstico de hipermobilidade articular benigna pelo Reumatologista. O paciente com hipermobilidade articular benigna pode desenvolver sintomas articulares como artralgia devido a uma inflamação articular. Acreditamos na possibilidade de que síndrome de Brown possa ter ocorrido devido a processo inflamatório na tróclea que teve início devido a hipermobilidade articular benigna.Brown's syndrome is characterized by a limitation of elevation in adduction, slight or normal limitation of elevation in abduction, divergence in straight upgaze (V-pattern, intorsion in upgaze and positive forced duction. It is caused by a tight or inelastic superior oblique tendon. Benign joint hypermobility is a hereditary disease of the connective tissue characterized by an increase of mobility in diverse joints. Its prevalence is very changeable regarding age range, sex and ethnicity, varying from 2 to 35% in men and 5 to 57% in women. In

Brown carbon formation from ketoaldehydes of biogenic monoterpenes

Energy Technology Data Exchange (ETDEWEB)

Nguyen, Tran B.; Laskin, Alexander; Laskin, Julia; Nizkorodov, Sergey

2013-04-10

Sources and chemical composition of the brown carbon are poorly understood, and even less is known about the mechanisms of its atmospheric transformations. This work presents molecular level investigation of the reactive compound ketolimononaldehyde (KLA, C9H14O3), a second generation ozonolysis product of limonene (C10H16), as a potent brown carbon precursor in secondary organic aerosol (SOA) through its reactions with reduced nitrogen compounds such as ammonium ion (NH4+), ammonia, and amino acids. The reactions of synthesized and purified KLA with NH4+ and glycine resulted in the formation of chromophores nearly identical in spectral properties and formation rates to those found in similarly-aged limonene/O3 SOA. Similar chemical reaction processes of limononaldehyde (LA, C10H16O2) and pinonaldehyde (PA, C10H16O2), the first-generation ozonolysis products in the oxidation of limonene and α-pinene, respectively, were also studied, but the resulting products did not exhibit light absorption properties of brown carbon, suggesting that the unique molecular structure of KLA produces visible-light-absorbing compounds. The KLA/NH4+ and KLA/GLY reactions produce water-soluble, hydrolysis-resilient chromophores with high mass absorption coefficients (MAC = 2000-4000 cm2 g-1) at λ ~ 500 nm, precisely at the maximum of the solar emission spectrum. Liquid chromatography was used to isolate the light-absorbing fraction, and UV-Vis, FTIR, NMR and high-resolution mass spectrometry (HR-MS) techniques were used to investigate the structures and chemical properties of the light-absorbing compounds. The KLA browning reaction generates a diverse mixture of light-absorbing compounds, with the majority of the observable products containing 1-4 units of KLA and 0-2 nitrogen atoms. Based on the HR-MS product distribution, conjugated aldol condensates, secondary imines (Schiff bases), and N-heterocycles like pyrroles may contribute in varying degree to the light-absorbing properties

Microwave-assisted co-pyrolysis of brown coal and corn stover for oil production.

Science.gov (United States)

Zhang, Yaning; Fan, Liangliang; Liu, Shiyu; Zhou, Nan; Ding, Kuan; Peng, Peng; Anderson, Erik; Addy, Min; Cheng, Yanling; Liu, Yuhuan; Li, Bingxi; Snyder, John; Chen, Paul; Ruan, Roger

2018-07-01

The controversial synergistic effect between brown coal and biomass during co-pyrolysis deserves further investigation. This study detailed the oil production from microwave-assisted co-pyrolysis of brown coal (BC) and corn stover (CS) at different CS/BC ratios (0, 0.33, 0.50, 0.67, and 1) and pyrolysis temperatures (500, 550, and 600 °C). The results showed that a higher CS/BC ratio resulted in higher oil yield, and a higher pyrolysis temperature increased oil yield for brown coal and coal/corn mixtures. Corn stover and brown coal showed different pyrolysis characteristics, and positive synergistic effect on oil yield was observed only at CS/BC ratio of 0.33 and pyrolysis temperature of 600 °C. Oils from brown coal mainly included hydrocarbons and phenols whereas oils from corn stover and coal/corn mixtures were dominated by ketones, phenols, and aldehydes. Positive synergistic effects were observed for ketones, aldehydes, acids, and esters whereas negative synergistic effects for hydrocarbons, phenols and alcohols. Copyright © 2018 Elsevier Ltd. All rights reserved.

The impact of germination on the characteristics of brown rice flour and starch.

Science.gov (United States)

Xu, Jie; Zhang, Hui; Guo, Xiaona; Qian, Haifeng

2012-01-30

In recent years, germinated brown rice as a functional food has received great attention with its improved sensory and nutritional properties. Particularly of interest are the high levels of γ-amino butyric acid (GABA) which can be obtained during germination. However, more studies are needed to fully understand the effect of germination on the physicochemical properties of brown rice. Germination altered the chemical composition of brown rice, resulting in an increase in reducing sugar and ash content, and a reduction in amylose. Solubility, paste viscosity, transition temperatures (T(o) , T(p) and T(c) ) and percentage of retrogradation (%Retrogradation) were decreased, while swelling power and turbidity were significantly increased. Scanning electron micrographs indicated that starch granules from germinated brown rice became smaller and less homogeneous. Moreover, germination shortened the chain length of amylopectin and amylose molecules. This investigation provides information on changes in the characteristics of rice flour and rice starch during germination, leading to a better understanding on the chemistry of brown rice germination. Copyright © 2011 Society of Chemical Industry.

Could brown bears (Ursus arctos) have survived in Ireland during the Last Glacial Maximum?

Science.gov (United States)

Leonard, Saoirse A; Risley, Claire L; Turvey, Samuel T

2013-08-23

Brown bears are recorded from Ireland during both the Late Pleistocene and early-mid Holocene. Although most of the Irish landmass was covered by an ice sheet during the Last Glacial Maximum (LGM), Irish brown bears are known to have hybridized with polar bears during the Late Pleistocene, and it is suggested that the Irish brown bear population did not become extinct but instead persisted in situ through the LGM in a southwestern ice-free refugium. We use historical population modelling to demonstrate that brown bears are highly unlikely to have survived through the LGM in Ireland under any combination of life-history parameters shown by living bear populations, but instead would have rapidly become extinct following advance of the British-Irish ice sheet, and probably recolonized Ireland during the end-Pleistocene Woodgrange Interstadial from a closely related nearby source population. The time available for brown bear-polar bear hybridization was therefore restricted to narrow periods at the beginning or end of the LGM. Brown bears would have been extremely vulnerable to extinction in Quaternary habitat refugia and required areas substantially larger than southwestern Ireland to survive adverse glacial conditions.

Early Overfeed-Induced Obesity Leads to Brown Adipose Tissue Hypoactivity in Rats

Directory of Open Access Journals (Sweden)

Douglas L. de Almeida

2013-12-01

Full Text Available Background/Aims: Brown adipose tissue activation has been considered a potential anti-obesity mechanism because it is able to expend energy through thermogenesis. In contrast, white adipose tissue stores energy, contributing to obesity. We investigated whether the early programming of obesity by overfeeding during lactation changes structure of interscapular brown adipose tissue in adulthood and its effects on thermogenesis. Methods: Birth of litters was considered day 0. On day 2, litter size was adjusted to normal (9 pups and small (3 pups litters. On day 21, the litters were weaned. A temperature transponder was implanted underneath interscapular brown adipose tissue pads of 81-day-old animals; local temperature was measured during light and dark periods between days 87 and 90. The animals were euthanized, and tissue and blood samples were collected for further analysis. The vagus and retroperitoneal sympathetic nerve activity was recorded. Results: Small litter rats presented significant lower interscapular brown adipose tissue temperature during the light (NL 37.6°C vs. SL 37.2°C and dark (NL 38°C vs. SL 37.6°C periods compared to controls. Morphology of small litter brown adipose tissue showed fewer lipid droplets in the tissue center and more and larger in the periphery. The activity of vagus nerve was 19,9% greater in the small litter than in control (pConclusion: Early overfeeding programming of obesity changes the interscapular brown adipose tissue structure in adulthood, leading to local thermogenesis hypoactivity, which may contribute to obesity in adults.

New approach to brown coal pricing using internal rate of return methodology

International Nuclear Information System (INIS)

Bejbl, Jan; Bemš, Julius; Králík, Tomáš; Starý, Oldřich; Vastl, Jaromír

2014-01-01

Highlights: • We showed that brown coal is the substitute for black coal only at the time of the investment decision. • We compiled the model used in a calculation of the economically justified price for the productive and extractive component. • The resulting economically justified price is on a par with the current black coal price. • The proposed methodological approach is applicable to solve similar tasks not only in the energy sector. - Abstract: Brown coal is one of the dominant local strategic raw materials in Europe, used, to a large extent, in the power-generating industry. The current situation, where the price of gas and electricity precludes the efficient use of gas sources, leads to the extraction of older sources, chiefly brown coal ones. In tandem with a turning away from nuclear power, brown coal is experiencing a renaissance and the issue of brown coal price setting is, and will be, relevant. This paper deals with a proposal of a new method for determining the base price, consisting of defining the reference fuel chain for electricity and heat production based on brown coal. It builds on the notion that the degree of risk of the involved parties should be reflected in the modified amount of revenue per capital invested. The resulting price is then an economically justified price which encourages a respect for the specific features of the market in question and set the base price of the commodity in a way that is acceptable for both the extractive and the productive components of the fuel chain

Phylogeographic structure and demographic patterns of brown trout in North-West Africa.

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Snoj, Aleš; Marić, Saša; Bajec, Simona Sušnik; Berrebi, Patrick; Janjani, Said; Schöffmann, Johannes

2011-10-01

The objectives of the study were to determine the phylogeographic structure of brown trout (Salmo trutta) in Morocco, elucidate their colonization patterns in North-West Africa and identify the mtDNA lineages involved in this process. We also aimed to resolve whether certain brown trout entities are also genetically distinct. Sixty-two brown trout from eleven locations across the Mediterranean and the Atlantic drainages in Morocco were surveyed using sequence analysis of the mtDNA control region and nuclear gene LDH, and by genotyping twelve microsatellite loci. Our study confirms that in Morocco both the Atlantic and Mediterranean basins are populated by Atlantic mtDNA lineage brown trout only, demonstrating that the Atlantic lineage (especially its southern clade) invaded initially not only the western part of the Mediterranean basin in Morocco but also expanded deep into the central area. Atlantic haplotypes identified here sort into three distinct groups suggesting Morocco was colonized in at least three successive waves (1.2, 0.4 and 0.2-0.1 MY ago). This notion becomes more pronounced with the finding of a distinct haplotype in the Dades river system, whose origin appears to coalesce with the nascent stage of the basal mtDNA evolutionary lineages of brown trout. According to our results, Salmo akairos, Salmo pellegrini and "green trout" from Lake Isli do not exhibited any character states that distinctively separate them from the other brown trout populations studied. Therefore, their status as distinct species was not confirmed. Copyright © 2011 Elsevier Inc. All rights reserved.

Chemical Properties of Brown Carbon Aerosol Generated at the Missoula Fire Sciences Laboratory

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Washenfelder, R. A.; Womack, C.; Franchin, A.; Middlebrook, A. M.; Wagner, N.; Manfred, K.

2017-12-01

Aerosol scattering and absorption are still among the largest uncertainties in quantifying radiative forcing. Biomass burning is a major source of light-absorbing carbonaceous aerosol in the United States. These aerosol are generally classified into two categories: black carbon (graphitic-like aerosol that absorbs broadly across the ultraviolet and visible spectral regions) and brown carbon (organic aerosol that absorbs strongly in the ultraviolet and near-visible spectral regions). The composition, volatility, and chemical aging of brown carbon are poorly known, but are important to understanding its radiative effects. We deployed three novel instruments to the Missoula Fire Sciences Laboratory in 2016 to measure brown carbon absorption: a photoacoustic spectrometer, broadband cavity enhanced spectrometer, and particle-into-liquid sampler coupled to a liquid waveguide capillary cell. The instruments sampled from a shared inlet with well-characterized dilution and thermal denuding. We sampled smoke from 32 controlled burns of fuels relevant to western U.S. wildfires. We use these measurements to determine the volatility of water-soluble brown carbon, and compare this to the volatility of water-soluble organic aerosol and total organic aerosol. We further examine the wavelength-dependence of the water-soluble brown carbon absorption as a function of denuder temperature. Together this gives new information about the solubility, volatility, and chemical composition of brown carbon.

CRITICAL SUCCESS FACTORS FOR BROWN-FIELD CAPITAL AND RENEWAL PROJECTS

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J. Warchol

2012-01-01

Full Text Available

ENGLISH ABSTRACT: Manufacturing companies operate in a business environment where incremental growth may be achieved through expansion and renewal of existing plant and facilities. Effective management of the critical success factors of such capital development projects may also provide competitive advantage. These projects tend to be of a brown-field nature, characterised by a significant level of risk arising from the interaction between the project implementation and concurrent operation of the existing physical asset base. So it is vital to understand the factors that influence the success of capital expansion and renewal projects in the brown-field context. Although each project has unique features, there are critical success factors that can be customised for successful outcomes in the brown-field environment. This study identifies five critical success factors applicable to brown-field capital expansion and renewal projects. Managerial focus on the critical factors, and the prospects for successful brown-field projects, are discussed in the paper.

AFRIKAANSE OPSOMMING: Vervaardigers funksioneer in ‘n sakeomgewing waar voortgesette groei bereik word via uitbreiding en hernuwing van bestaande fasiliteite. Die doeltreffende bestuur van kritiese suksesfaktore van sodanige kapitaalprojekte bied geleentheid vir mededingende voordeel. Projekte van hierdie aard neig om geklassifiseer te word as van herontwikkelingsaard, met betekenisvolle gepaardgaande risiko wat voortspruit uit die interaksie tussen projekimplementering en gelyktydige bedryf van bestaande fisiese bates. Derhalwe is dit belangrik om in die konteks van herontwikkeling aandag te gee aan die kritiese faktore wat ‘n rol speel in die bereiking van sukses. Die navorsing identifiseer vyf kritiese suksesfaktore van belang vir uitbreidings- en vernuwingsprojekte.

Prying the Gates Wide Open: Academic Freedom and Gender Equality at Brown University, 1974-1977

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Porwancher, Andrew

2013-01-01

In 1974, Brown University's Department of Anthropology denied tenure to assistant professor Louise Lamphere. Convinced that her dismissal was the product of sex discrimination, Lamphere filed suit against Brown. Lamphere and three other female scholars who joined her suit successfully pressed Brown into an out-of-court settlement in 1977.…

Brown tumor: clinical findings of secondary hyperparathyroidism in patients with renal osteodystrophy.

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Silva, Mairaira Teles Leão E; Cedraz, Juliana Silva Barros; Pontes, Caetano Guilherme Carvalho; Trento, Cleverson Luciano; Brasileiro, Bernardo Ferreira; Piva, Marta Rabello; Pereira, Fabiano Alvim

2017-01-01

A brown tumor, or osteoclastoma, is a nonneoplastic bony lesion associated with hyperparathyroidism and directly related to increased levels of parathyroid hormone. These tumors result from excessive osteoclastic activity. This article presents 3 cases of brown tumor localized in facial bones. The lesions were the result of secondary hyperparathyroidism associated with chronic renal failure. The patients were two 42-year-old men and a 39-year-old woman. All patients had been treated systemically by hemodialysis for more than 10 years. This article highlights the importance of proper diagnosis and management of dental patients presenting with a brown tumor.

Characterization of the central neural projections to brown, white, and beige adipose tissue.

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Wiedmann, Nicole M; Stefanidis, Aneta; Oldfield, Brian J

2017-11-01

The functional recruitment of classic brown adipose tissue (BAT) and inducible brown-like or beige fat is, to a large extent, dependent on intact sympathetic neural input. Whereas the central neural circuits directed specifically to BAT or white adipose tissue (WAT) are well established, there is only a developing insight into the nature of neural inputs common to both fat types. Moreover, there is no clear view of the specific central and peripheral innervation of the browned component of WAT: beige fat. The objective of the present study is to examine the neural input to both BAT and WAT in the same animal and, by exposing different cohorts of rats to either thermoneutral or cold conditions, define changes in central neural organization that will ensure that beige fat is appropriately recruited and modulated after browning of inguinal WAT (iWAT). At thermoneutrality, injection of the neurotropic (pseudorabies) viruses into BAT and WAT demonstrates that there are dedicated axonal projections, as well as collateral axonal branches of command neurons projecting to both types of fat. After cold exposure, central neural circuits directed to iWAT showed evidence of reorganization with a greater representation of command neurons projecting to both brown and beiged WAT in hypothalamic (paraventricular nucleus and lateral hypothalamus) and brainstem (raphe pallidus and locus coeruleus) sites. This shift was driven by a greater number of supraspinal neurons projecting to iWAT under cold conditions. These data provide evidence for a reorganization of the nervous system at the level of neural connectivity following browning of WAT.-Wiedmann, N. M., Stefanidis, A., Oldfield, B. J. Characterization of the central neural projections to brown, white, and beige adipose tissue. © FASEB.

Antimicrobials for reduction of Salmonella contamination in uncooked, surface-browned breaded chicken products.

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Moschonas, Galatios; Geornaras, Ifigenia; Stopforth, Jarret D; Wach, Damien; Woerner, Dale R; Belk, Keith E; Smith, Gary C; Sofos, John N

2012-06-01

Surface-browned but uncooked frozen breaded chicken products have been associated with salmonellosis outbreaks due to inadequate or no cooking of the products before consumption. This study was conducted to evaluate the effect of three antimicrobials against Salmonella during manufacture of a surface-browned, uncooked frozen breaded chicken meat product. Fresh chicken breast meat portions (5 by 5 by 5 cm) were inoculated (4 to 5 log CFU/g) with Salmonella and mixed with caprylic acid (CAA; 0.5 and 1.0%), carvacrol (CAR; 0.3 and 0.5%), ε-polylysine (POL; 0.125 and 0.25%), or distilled water (control). Sodium chloride (1.2%) and sodium tripolyphosphate (0.3%) were added to all treatments, and the mixtures were ground (5% total moisture enhancement level) and formed into portions (9 by 5 by 3 cm). The products were breaded and surface browned by baking in an oven (208°C for 15 min) or deep frying in vegetable oil (190°C for 15 s), packaged in polyethylene bags, and stored at -20°C for 7 days. Total reductions of inoculated Salmonella in untreated control oven- or fryer-browned products after frozen storage were 1.2 and 0.8 log CFU/g, respectively. In comparison, treatment with CAA, CAR, or POL reduced initial pathogen counts by 3.3 to >4.5, 4.1 to >4.7, and 1.1 to 1.6 log CFU/g, respectively, regardless of the antimicrobial concentration and browning method. Treatment with 1.0% CAA (oven browned) or 0.5% CAR (oven or fryer browned) reduced Salmonella to nondetectable levels (chicken products.

Survival of a brown dwarf after engulfment by a red giant star.

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Maxted, P F L; Napiwotzki, R; Dobbie, P D; Burleigh, M R

2006-08-03

Many sub-stellar companions (usually planets but also some brown dwarfs) orbit solar-type stars. These stars can engulf their sub-stellar companions when they become red giants. This interaction may explain several outstanding problems in astrophysics but it is unclear under what conditions a low mass companion will evaporate, survive the interaction unchanged or gain mass. Observational tests of models for this interaction have been hampered by a lack of positively identified remnants-that is, white dwarf stars with close, sub-stellar companions. The companion to the pre-white dwarf AA Doradus may be a brown dwarf, but the uncertain history of this star and the extreme luminosity difference between the components make it difficult to interpret the observations or to put strong constraints on the models. The magnetic white dwarf SDSS J121209.31 + 013627.7 may have a close brown dwarf companion but little is known about this binary at present. Here we report the discovery of a brown dwarf in a short period orbit around a white dwarf. The properties of both stars in this binary can be directly observed and show that the brown dwarf was engulfed by a red giant but that this had little effect on it.

The Influence of Fisheries Management on the Brown Trout Population in Moravice River

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Petr Chalupa

2016-01-01

Full Text Available In 2013, an ichthyological investigation with focus on the population of brown trout (Salmo trutta m. fario in Moravice River above Slezská Harta dam reservoir in 6 localities of two salmonid fisheries was conducted (3 locations in fishery Moravice 7 and 3 locations in fishery Moravice 8. Ichthyological investigation in 2013 found abundance of brown trout in fishery Moravice 7 1,621 pcs/ha, in fishery Moravice 8 668 pcs/ha. These results were compared with the results of ichthyological investigations from 2004 (Spurný et al. 2006 and 2012 (unpublished data that were conducted in the same locations of salmonid fisheries of Moravice 7 and Moravice 8. Over 10 years the size structure of brown trout population has changed, which was shown as higher proportion of juvenile fish in size (TL to 15 cm. The average abundance of brown trout with TL up to 15 cm reached in fishery Moravice 7 in 2004 15 pcs/ha (Spurný et al. 2006, in 2013 1,039 pcs/ha, in fishery Moravice 8 in 2004 719 pcs/ha and in 2012 2,234 pcs/ha. Change in size structure of population of brown trout in monitored localities between 2004, 2012 and 2013 was evaluated as statistically significant (d. f. 10; F = 12.8; P < 0.05. Ichthyologic investigations in 2004 (Spurný et al. 2006, 2012 (unpublished data and 2013 determined also abundance of brown trout in fishing size (TL over 25 cm: 54 pcs/ha in 2004 (Spurný et al. 2006, in 2012 (unpublished data 41 pcs/ha, and in 2013 56 pcs/ha. These values were compared with catches of anglers, and according to the results we can say that the fishing pressure had no effect on the abundance of brown trout in fishing size. Abundance of brown trout in salmonid fisheries Moravice 7 and Moravice 8 is probably affected by drought and occurrence of piscivorous predators.

Brown midrib sorghum deserves a look

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Forage sorghum varieties have been developed to allow them to thrive under low moisture and poor soil conditions while producing adequate amounts of forage. In addition, newer varieties, such as the brown midrib (BMR) hybrids, can be alternatives to conventional varieties as they contain less lignin...

Application of exogenous ethylene inhibits postharvest peel browning of ‘Huangguan’ pear

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Peel browning disorder has an enormous impact on the exterior quality of ‘Huangguan’ pear whereas the underlying mechanism is still unclear. In this study, the effect of exogenous ethylene on peel browning of pear fruits stored at 0' was evaluated. Results showed that ethylene effectively inhibited ...

Detection, breeding, and selection of durable resistance to brown rust in sugarcane

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Brown rust, caused by Puccinia melanocephala, is an important disease of sugarcane in Louisiana. The adaptability of the pathogen has repeatedly resulted in resistant cultivars becoming susceptible once they are widely grown. The frequency of the brown rust resistance gene Bru1 was low in the breedi...

Glyphosate Control of Orange and Brown Rusts in Glyphosate-Sensitive Sugarcane Cultivars

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Technical Abstract: Brown and orange rust diseases cause substantial yield reductions on sugarcane (Saccharum spp.) in Florida and other regions where sugarcane is grown. Brown rust caused by Puccinia melanocephala Syd. & P. Syd has been present in Florida since 1978 and orange rust caused by Pucci...

Global Expression in Sorghum Brown Midrib Mutants to Improve Biomass for Biofuels

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Brown midrib (bmr) mutants are being investigated for their ability to increase the conversion efficiency of sorghum biomass for lignocellulosic bioenergy. Brown midrib 6 and 12 (bmr6 and 12) are impaired the last two steps of monolignol biosynthesis resulting in reduced lignin content and altered ...

Image analysis to evaluate the browning degree of banana (Musa spp.) peel.

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Cho, Jeong-Seok; Lee, Hyeon-Jeong; Park, Jung-Hoon; Sung, Jun-Hyung; Choi, Ji-Young; Moon, Kwang-Deog

2016-03-01

Image analysis was applied to examine banana peel browning. The banana samples were divided into 3 treatment groups: no treatment and normal packaging (Cont); CO2 gas exchange packaging (CO); normal packaging with an ethylene generator (ET). We confirmed that the browning of banana peels developed more quickly in the CO group than the other groups based on sensory test and enzyme assay. The G (green) and CIE L(∗), a(∗), and b(∗) values obtained from the image analysis sharply increased or decreased in the CO group. And these colour values showed high correlation coefficients (>0.9) with the sensory test results. CIE L(∗)a(∗)b(∗) values using a colorimeter also showed high correlation coefficients but comparatively lower than those of image analysis. Based on this analysis, browning of the banana occurred more quickly for CO2 gas exchange packaging, and image analysis can be used to evaluate the browning of banana peels. Copyright © 2015 Elsevier Ltd. All rights reserved.

New Light on Dark Stars Red Dwarfs, Low-Mass Stars, Brown Dwarfs

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Reid, I. Neill

2005-01-01

There has been very considerable progress in research into low-mass stars, brown dwarfs and extrasolar planets during the past few years, particularly since the fist edtion of this book was published in 2000. In this new edtion the authors present a comprehensive review of both the astrophysical nature of individual red dwarf and brown dwarf stars and their collective statistical properties as an important Galactic stellar population. Chapters dealing with the observational properies of low-mass dwarfs, the stellar mass function and extrasolar planets have been completely revised. Other chapters have been significantly revised and updated as appropriate, including important new material on observational techniques, stellar acivity, the Galactic halo and field star surveys. The authors detail the many discoveries of new brown dwarfs and extrasolar planets made since publication of the first edition of the book and provide a state-of-the-art review of our current knowledge of very low-mass stars, brown dwarfs a...

Understanding of variability properties in very low mass stars and brown dwarfs

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Mondal, Soumen; Ghosh, Samrat; Khata, Dhrimadri; Joshi, Santosh; Das, Ramkrishna

2018-04-01

We report on photometric variability studies of a L3.5 brown dwarf 2MASS J00361617+1821104 (2M0036+18) in the field and of four young brown dwarfs in the star-forming region IC 348. From muti-epoch observations, we found significant periodic variability in 2M0036+18 with a period of 2.66 ± 0.55 hours on one occasion while it seemed to be non-variable on three other occasions. An evolving dust cloud might cause such a scenario. Among four young brown dwarfs of IC 348 in the spectral range M7.25 - M8, one brown dwarf 2MASS J03443921+3208138 shows significant variability. The K-band spectra (2.0-2.4 μm) of nine very low mass stars (M1 - M9 V) are used to characterize the water band index (H20-K2). We found that it is strongly correlated with the surface temperature of M dwarfs.

Brown and beige fat in humans: thermogenic adipocytes that control energy and glucose homeostasis.

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Sidossis, Labros; Kajimura, Shingo

2015-02-01

Brown adipose tissue (BAT), a specialized fat that dissipates energy to produce heat, plays an important role in the regulation of energy balance. Two types of thermogenic adipocytes with distinct developmental and anatomical features exist in rodents and humans: classical brown adipocytes and beige (also referred to as brite) adipocytes. While classical brown adipocytes are located mainly in dedicated BAT depots of rodents and infants, beige adipocytes sporadically reside with white adipocytes and emerge in response to certain environmental cues, such as chronic cold exposure, a process often referred to as "browning" of white adipose tissue. Recent studies indicate the existence of beige adipocytes in adult humans, making this cell type an attractive therapeutic target for obesity and obesity-related diseases, including type 2 diabetes. This Review aims to cover recent progress in our understanding of the anatomical, developmental, and functional characteristics of brown and beige adipocytes and discuss emerging questions, with a special emphasis on adult human BAT.

Relying on fin erosion to identify hatchery-reared brown trout in a Tennessee river

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Meerbeek, Jonathan R.; Bettoli, Phillip William

2012-01-01

Hatchery-induced fin erosion can be used to identify recently stocked catchable-size brown trout Salmo trutta during annual surveys to qualitatively estimate contributions to a fishery. However, little is known about the longevity of this mark and its effectiveness as a short-term (≤ 1 year) mass-marking technique. We evaluated hatchery-induced pectoral fin erosion as a mass-marking technique for short-term stocking evaluations by stocking microtagged brown trout in a tailwater and repeatedly sampling those fish to observe and measure their pectoral fins. At Dale Hollow National Fish Hatchery, 99.1% (228 of 230) of microtagged brown trout in outdoor concrete raceways had eroded pectoral fins 1 d prior to stocking. Between 34 and 68 microtagged and 26-35 wild brown trout were collected during eight subsequent electrofishing samples. In a blind test based on visual examination of pectoral fins at up to 322 d poststocking, one observer correctly identified 91.7% to 100.0% (mean of 96.9%) of microtagged brown trout prior to checking for microtags. In the laboratory, pectoral fin length and width measurements were recorded to statistically compare the fin measurements of wild and microtagged hatchery brown trout. With only one exception, all pectoral fin measurements on each date averaged significantly larger for wild trout than for microtagged brown trout. Based on the number of pectoral fin measurements falling below 95% prediction intervals, 93.7% (148 of 158) of microtagged trout were correctly identified as hatchery fish based on regression models up to 160 d poststocking. Only 72.2% (70 of 97) of microtagged trout were identified correctly after 160 d based on pectoral fin measurements and the regression models. We concluded that visual examination of pectoral fin erosion was a very effective way to identify stocked brown trout for up to 322 d poststocking.