Investigations on the Effects of Five Different Plant Extracts on the Two-Spotted Mite Tetranychus urticae Koch (Arachnida: Tetranychidae

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Pervin Erdogan

2012-01-01

Full Text Available Two-spotted mite, Tetranychus urticae Koch (Arac.: Tetranychidae, is an economic pest worldwide including Turkey, causing serious damage to vegetables, flowers, and fruit crops. In recent years, broad-spectrum insecticides/miticides have been used to control this pest in Turkey. Control is difficult mainly due to resistance to conventional pesticides. This study was conducted to determine efficacy of pesticides extracted from five different plants [i.e., Allium sativum L. (Amaryllidaceae, Rhododendron luteum S. (Ericaceae, Helichrysum arenarium L. (Asteraceae, Veratrum album L. (Liliaceae, and Tanacetum parthenium L. (Asteraceae] against this mite. Bioassays were tested by two different methods to determine the effects of varying concentrations. Experiments were performed using 3 cm diameter leaf disk from unsprayed bean plants (Phaseolus vulgaris L.. In addition, the effects of the extracts on reproduction and oviposition were investigated. The extract yielded high mortality. In the lowest-concentration bioassays, the adult mites laid lower numbers of eggs compared to the untreated control. No ovicidal effect was observed.

Tri-trophic level Impact of Host Plant Linamarin and Lotaustralin on Tetranychus urticae (Mesostigmata: Tetranychidae) and its predator Phytoseiulus persimilis (Prostigmata: Phytoseiidae)

Science.gov (United States)

The impact of linamarin and lotaustralin content in the leaves of Phaseolus lunatus L. on the second and third trophic levels was studied in Tetranychus urticae (Koch) and its predator Phytoseiulus persimilis Athias-Henriot. Chemical analyzes showed that the content of linamarin was higher in termin...

Interaction between two predator mites of Tetranychus urticae koch (Acariformes: Tetranychidae) in laboratory

International Nuclear Information System (INIS)

Arguelles R, Angelica; Plazas, Natali; Bustos R, Alexander; Cantor R, Fernando; Rodriguez, Daniel; Hilarion, Alejandra

2013-01-01

Tetranychus urticae (Acari: Tetranychidae) is an important pest of ornamental crops. A species of predatory mite used for its control is Neoseiulus californicus and Phytoseiulus persimilis (Acari: Phytoseiidae). This research proposes the use of joint releases of the two cited predators for the control of the pest. Several situations leading to interaction were evaluated: high density of one predator and low density of the other one, being the prey present or absent. The scenario with predators in equal densities and in presence of the prey was also evaluated. When a predator is in higher density and the prey present, the predator with the lower density increases the interference with the consumption of preys by the predator with higher density. On the other hand, when the consumption of T. urticae reduces, intraguild predation increases. P. persimilis shows intraguild predation behavior when t. urticae is absent and N. californicus is present, consuming all developmental stages of its conspecific. Instead, N. californicus only feed on conspecific larvae, when the fitofagous was absent and P. persimilis was present. When the two predators were present in the same assemblage and with the same population density, the quantity of T. urticae consumed by both of them was not higher than the consumed one when each predator was present in separate way.

Aberrations of holokinetic chromosomes and associated lethality after X-irradiation of meiotic stages in Tetranychus urticae Koch (acari, tetranychidae)

International Nuclear Information System (INIS)

Tempelaar, M.J.

1979-01-01

Chromosomes of the holokinetic organization type were irradiated with X-rays in various stages of meiosis in unfertillized eggs of Tetranychus urticae Koch. Visible cytological aberrations, lethality and sterility were investigated in subsequent generations. Chromosome fragments are the most frequently occuring light-microscopically visible chromosome aberrations; bridges are not formed. Contrary to expectations, the presence of fragments appears to be positively correlated with the occurrence of lethality; loss of fragments, missegregation and the measure of damage of the broken chromosome parts are involved. In contrast with monokinetic chromosomes the earliest lethality occurs only after about 10 divisions. The ratios between different embryonic lethality types (early vs. late) differ depending on the stage irradiated: in more compact chromatin, more serious damage (i.e. more early lethality syndromes) is induced than in less compact chromatin. In the progeny of the surviving males, neither translocations nor independent fragments are found; indirect evidence indicated the occasional presence of inversions. The presumtive inversions are induced more frequently in a chromatin-compact stage (metaphase I) than in a less compact one (telophase I). (Auth.)

Binomial and enumerative sampling of Tetranychus urticae (Acari: Tetranychidae) on peppermint in California.

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Tollerup, Kris E; Marcum, Daniel; Wilson, Rob; Godfrey, Larry

2013-08-01

The two-spotted spider mite, Tetranychus urticae Koch, is an economic pest on peppermint [Mentha x piperita (L.), 'Black Mitcham'] grown in California. A sampling plan for T. urticae was developed under Pacific Northwest conditions in the early 1980s and has been used by California growers since approximately 1998. This sampling plan, however, is cumbersome and a poor predictor of T. urticae densities in California. Between June and August, the numbers of immature and adult T. urticae were counted on leaves at three commercial peppermint fields (sites) in 2010 and a single field in 2011. In each of seven locations per site, 45 leaves were sampled, that is, 9 leaves per five stems. Leaf samples were stratified by collecting three leaves from the top, middle, and bottom strata per stem. The on-plant distribution of T. urticae did not significantly differ among the stem strata through the growing season. Binomial and enumerative sampling plans were developed using generic Taylor's power law coefficient values. The best fit of our data for binomial sampling occurred using a tally threshold of T = 0. The optimum number of leaves required for T urticae at the critical density of five mites per leaf was 20 for the binomial and 23 for the enumerative sampling plans, respectively. Sampling models were validated using Resampling for Validation of Sampling Plan Software.

The Effect of Spiromesifen on the Reproductive Potential of Tetranychus urticae Koch (Acari: Tetranychidae

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Dejan Marčić

2009-01-01

Full Text Available Laboratory bioassays were conducted to evaluate the effects of spiromesifen on the fecundity, fertility and population growth of two-spotted spider mite (Tetranychus urticae Koch after treatment of pre-ovipositing females with five acaricide concentrations: 180mg/l (maximum recommended concentration for use in glasshouses against spider mites, 18 mg/l, 1.8 mg/l and 0.18 mg/l (the last one was discriminative for eggs and immatures in preliminary studies, i.e. produced 100% mortality of those stages and 0.018 mg/l. After24h exposure, the percentages of females surviving treatment without visible symptoms of poisoning were 50% (180 mg/l, 45% (18 mg/l, 51% (1.8 mg/l, 74% (0.18 mg/l, 96% (0.018 mg/l and 98% (0 mg/l. Over the first four days after treatment, the females that survived180 mg/l and 18 mg/l laid no eggs. The total number of eggs laid after treatment with these two concentrations was reduced to less than 2% against the control by the end of the trial. The females that survived 1.8 mg/l laid 50% less eggs, compared to the control, while the number of eggs laid by the females treated with 0.18 mg/l and 0.018 mg/l were 19% and 4% lower, respectively. Over the initial four days, egg hatch rates in treatments were 73-87%, and 92-93% in the control. Significant statistical differences between gross fecundity (FCg and gross fertility (FTg values in the control and treatments were detected for females surviving 180 mg/l, 18 mg/l and 1.8 mg/l. On the other hand, only the net fertility (FTn value of females treated with 0.018 mg/l showed no statistically significant difference from the control value. Treatments with 180 mg/l and 18 mg/l significantly reduced the instantaneous rate of increase (ri 6, 8 and 10 days after treatment, compared to the control. The negative ri values in those treatments indicated a declining population. Sublethal effects of spiromesifen and its impact on T. urticae management are discussed.

Effect of acaricidal activity of Solanum nigrum on Tetranychus ...

African Journals Online (AJOL)

Effect of acaricidal activity of Solanum nigrum on Tetranychus urticae Koch under laboratory conditions. Stephanie Johana Numa Vergel, Lorena Rodríguez Coy, Daniel Rodríguez Caicedo, Ericsson Coy-Barrera ...

Phenotypic- and Genotypic-Resistance Detection for Adaptive Resistance Management in Tetranychus urticae Koch.

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Deok Ho Kwon

Full Text Available Rapid resistance detection is necessary for the adaptive management of acaricide-resistant populations of Tetranychus urticae. Detection of phenotypic and genotypic resistance was conducted by employing residual contact vial bioassay (RCV and quantitative sequencing (QS methods, respectively. RCV was useful for detecting the acaricide resistance levels of T. urticae, particularly for on-site resistance detection; however, it was only applicable for rapid-acting acaricides (12 out of 19 tested acaricides. QS was effective for determining the frequencies of resistance alleles on a population basis, which corresponded to 12 nonsynonymous point mutations associated with target-site resistance to five types of acaricides [organophosphates (monocrotophos, pirimiphos-methyl, dimethoate and chlorpyrifos, pyrethroids (fenpropathrin and bifenthrin, abamectin, bifenazate and etoxazole]. Most field-collected mites exhibited high levels of multiple resistance, as determined by RCV and QS data, suggesting the seriousness of their current acaricide resistance status in rose cultivation areas in Korea. The correlation analyses revealed moderate to high levels of positive relationships between the resistance allele frequencies and the actual resistance levels in only five of the acaricides evaluated, which limits the general application of allele frequency as a direct indicator for estimating actual resistance levels. Nevertheless, the resistance allele frequency data alone allowed for the evaluation of the genetic resistance potential and background of test mite populations. The combined use of RCV and QS provides basic information on resistance levels, which is essential for choosing appropriate acaricides for the management of resistant T. urticae.

TOXICIDADE DE ÓLEOS ESSENCIAIS PARA O CONTROLE DE Tetranychus urticae KOCH, 1836 (ACARI: TETRANYCHIDAE)

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Camila Santos Teixeira; Camila Costabeber Nunes; Romário Vargas; José Romário de Carvalho; Hugo Bolsoni Zago

2017-01-01

O ácaro rajado é considerado uma importante praga agrícola, causando danos em diferentes cultivos. O controle à base de acaricidas químicos pode vir a causar problemas ambientais e à saúde do homem. Desta forma o uso de óleos essenciais obtidos de produtos botânicos é uma alternativa no controle de pragas por apresentar baixo efeito residual, sendo objetivo deste trabalho avaliar a mortalidade e o efeito na fertilidade de fêmeas adultas de Tetranychus urticae submetidas a tratamentos com óleo...

Ethanol extract of Cymbopogon winterianus on mortality and number of eggs of Tetranychus urticae

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Victor Bernardo Vicentini

2015-07-01

Full Text Available Plant extracts have been studied as a promising source of natural insecticides. This study assessed the effect of the ethanol extract of Cymbopogon winterianus Jowitt (citronella grass in comparison with an insecticide containing azadirachtin (ICA on mortality and number of eggs of Tetranychus urticae Koch (Acari: Tetranychidae in laboratory conditions. For the tests, the mites were sprayed with the aid of a Potter spray tower. To assess the mortality of females, LC50 value for extract of citronella grass and ICA was, respectively, 2.63 and 2.83%. With respect to the number of eggs, the greatest reduction was observed at a concentration of 5% for the evaluation period of 120h, both for the extract of citronella grass (86% and for ICA (81%. These results suggest the potential of the ethanol extract of citronella grass to control of T. urticae. However, experiments, under field conditions, involving other populations of T. urticae should be performed to verify the efficacy of this extract as an alternative to be used in pest management programs

Comparison and Characterization of Garlic (Allium sativum L. Bulbs Extracts and Their Effect on Mortality and Repellency of Tetranychus urticae Koch (Acari: Tetranychidae Comparación y Caracterización de Extractos de Bulbos de Ajo (Allium sativum L. y su Efecto en a Mortalidad y Repelencia de Tetranychus urticae Koch (Acari: Tetranychidae

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Carlos Augusto Hincapié Ll

2008-12-01

Full Text Available Tetranychus urticae Koch is a pest that causes great economic losses because it attacks a wide range of host plants. Also, some populations have developed resistance against commercial acaricides. This work compares different extracts from garlic (Allium sativum L. bulbs measuring their toxicity and repellency effects on T. urticae. Extracts were obtained using as solvents CO2 in supercritical conditions (CSC, ethanol and petroleum ether using soxhlet and soaking methods and soaking in water. The supercritical fluid extraction technique allows for obtaining extracts at low temperature using high pressures, avoiding compound degradation and making possible solvent separation by exposing the extract at room temperature. Mites were bred on bean plants (Phaseolus vulgaris L. in a laboratory environment in Laureles Campus, Universidad Pontificia Bolivariana, Medellín, Colombia. Mortality was evaluated putting 10 mites in P. vulgaris 3 cm diameter leaf discs previously submersed in the extract. The lowest mean lethal concentrations (LC50 were obtained with the CSC method (8.1188, 5.4105, 2.8206 mg g-1 at 24, 48 and 72 h, respectively. Extracts were characterized using gas chromatography/mass spectrometry (GC/MS, finding vinyl dithiins (63.11%, diallyl disulfide (10.88% and diallyl trisulfide (10.4% as the main compounds in the CSC extract. The main conclusion is that, in comparison with other techniques of extraction from garlic bulbs used in this study, supercritical fluids allow for obtaining extracts with a higher concentration of biologically active compounds against T. urticae.Tetranychus urticae Koch es una plaga que causa grandes pérdidas económicas porque ataca un numeroso grupo de cultivos. Además, algunas poblaciones han desarrollado resistencia a acaricidas comerciales. Este trabajo compara diferentes extractos a partir de bulbos de ajo (Allium sativum L. a través de su toxicidad y repelencia sobre T. urticae. Los extractos se

The predatory mite Neoseiulus womersleyi (Acari: Phytoseiidae) follows extracts of trails left by the two-spotted spider mite Tetranychus urticae (Acari: Tetranychidae).

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Shinmen, Tsubasa; Yano, Shuichi; Osakabe, Mh

2010-10-01

As it walks, the two-spotted spider mite Tetranychus urticae Koch (Acari: Tetranychidae) spins a trail of silk threads, that is followed by the predatory mite, Neoseiulus womersleyi Schicha (Acari: Phytoseiidae). Starved adult female N. womersleyi followed T. urticae trails laid down by five T. urticae females but did not follow a trail of one T. urticae female, suggesting that the amount of spun threads and their chemical components should correlate positively with the number of T. urticae individuals. To examine whether chemical components of T. urticae trails are responsible for the predatory mite's trail following, we collected separate T. urticae threads from the exuviae and eggs, and then washed the threads with methanol to separate chemical components from physical attributes of the threads. Female N. womersleyi did not follow T. urticae trails that had been washed with methanol but contained physical residues, but they did follow the direction to which the methanol extracts of the T. urticae trails was applied. These results suggest that the predatory mite follows chemical, not physical, attributes of T. urticae trails.

TOXICIDADE DE ÓLEOS ESSENCIAIS PARA O CONTROLE DE Tetranychus urticae KOCH, 1836 (ACARI: TETRANYCHIDAE

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Camila Santos Teixeira

2017-04-01

Full Text Available O ácaro rajado é considerado uma importante praga agrícola, causando danos em diferentes cultivos. O controle à base de acaricidas químicos pode vir a causar problemas ambientais e à saúde do homem. Desta forma o uso de óleos essenciais obtidos de produtos botânicos é uma alternativa no controle de pragas por apresentar baixo efeito residual, sendo objetivo deste trabalho avaliar a mortalidade e o efeito na fertilidade de fêmeas adultas de Tetranychus urticae submetidas a tratamentos com óleos essenciais de laranja doce e limoneno, fornecidos pela empresa Ferquima Indústria e Comércio LTDA., e pela empresa Pack Indústria e Comércio de Produtos Agropecuários LTDA., respectivamente. Para avaliar a ação fumigante do óleo essencial sobre os ácaros foram realizados testes submetendo fêmeas adultas de T. urticae à dose pura do óleo essencial utilizando as dosagens de 5, 15 e 25 µL em câmaras de fumigação. Após o período de exposição ao óleo foi contabilizado o número de ácaros mortos e a quantidade de ovos depositados. Os resultados não foram significativos para mortalidade e para fertilidade de fêmeas adultas de T. urticae.

Prey Preference of the Predatory Mite, Amblyseius swirskii between First Instar Western Flower Thrips Frankliniella occidentalis and Nymphs of the Twospotted Spider Mite Tetranychus urticae

OpenAIRE

Xu, Xuenong; Enkegaard, Annie

2010-01-01

The prey preference of polyphagous predators plays an important role in suppressing different species of pest insects. In this study the prey preference of the predatory mite, Amblyseius swirskii (Athias-Henriot) (Acari: Phytoseiidae) was examined between nymphs of the twospotted spider mite, Tetranychus urticae Koch (Acari: Tetranychidae) and first instar larvae of the western flower thrips, Frankliniella occidentalis (Pergande) (Thysanoptera: Thripidae), as well as between active and chrysa...

Biological control of Eotetranychus lewisi and Tetranychus urticae (Acari: Tetranychidae) on strawberry by four phytoseiids (Acari: Phytoseiidae).

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Howell, Anna D; Daugovish, Oleg

2013-02-01

The spider mite, Eotetranychus lewisi (McGregor) (Acari: Tetranychidae), is a new emerging pest in California commercial strawberries. The predatory mite Phytoseiulus persimilis (Athias-Henriot) (Acari: Phytoseiidae), typically used for biocontrol of Tetranychus urticae (Koch) (Acari: Tetranychidae), provided growers little to no control of E. lewisi. Four commonly used phytoseiid predatory mites: P. persimilis, Neoseiulus californicus (McGregor), N. fallacis (Garman), and Amblyseius andersoni (Chant), were used in lab studies to investigate which is best at managing E. lewisi populations. We als o investigated t he interactions between T. urticae and E. lewisi and in relation to phytoseiid efficiency given the potential for indirect effects of biocontrol. When E. lewisi and T. urticae are present on the same leaf, T. urticae populations increase and begin displacing E. lewisi. P. persimilis did not feed on E. lewisi, but the other three predatory mites consumed the spider mites and lowered their populations. When both E. lewisi and T. urticae are present on the same leaf, N. fallacis and A. andersoni fed on both types of mites equally and were capable of decreasing both populations. N. californicus fed on E. lewisi first and decreased its population, but allowed T. urticae populations to increase. P. persimilis may be insufficient at controlling E. lewisi and its use may instead enhance E. lewisi populations.

Divergent methylation pattern in adult stage between two forms of Tetranychus urticae (Acari: Tetranychidae).

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Yang, Si-Xia; Guo, Chao; Zhao, Xiu-Ting; Sun, Jing-Tao; Hong, Xiao-Yue

2017-02-19

The two-spotted spider mite, Tetranychus urticae Koch has two forms: green form and red form. Understanding the molecular basis of how these two forms established without divergent genetic background is an intriguing area. As a well-known epigenetic process, DNA methylation has particularly important roles in gene regulation and developmental variation across diverse organisms that do not alter genetic background. Here, to investigate whether DNA methylation could be associated with different phenotypic consequences in the two forms of T. urticae, we surveyed the genome-wide cytosine methylation status and expression level of DNA methyltransferase 3 (Tudnmt3) throughout their entire life cycle. Methylation-sensitive amplification polymorphism (MSAP) analyses of 585 loci revealed variable methylation patterns in the different developmental stages. In particular, principal coordinates analysis (PCoA) indicates a significant epigenetic differentiation between female adults of the two forms. The gene expression of Tudnmt3 was detected in all examined developmental stages, which was significantly different in the adult stage of the two forms. Together, our results reveal the epigenetic distance between the two forms of T. urticae, suggesting that DNA methylation might be implicated in different developmental demands, and contribute to different phenotypes in the adult stage of these two forms. © 2017 Institute of Zoology, Chinese Academy of Sciences.

Can Plant Defence Mechanisms Provide New Approaches for the Sustainable Control of the Two-Spotted Spider Mite Tetranychus urticae?

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Blas Agut

2018-02-01

Full Text Available Tetranychus urticae (T. urticae Koch is a cosmopolitan, polyphagous mite which causes economic losses in both agricultural and ornamental plants. Some traits of T. urticae hamper its management, including a short life cycle, arrhenotokous parthenogenesis, its haplodiploid sex determination system, and its extraordinary ability to adapt to different hosts and environmental conditions. Currently, the use of chemical and biological control are the major control methods used against this mite. In recent years, some studies have focused on plant defence mechanisms against herbivores. Various families of plant compounds (such as flavonoids, glucosinolates, or acyl sugars have been shown to behave as acaricides. Plants can be induced upon appropriate stimuli to increase their resistance against spider mites. This knowledge, together with the understanding of mechanisms by which T. urticae detoxifies and adapts to pesticides, may complement the control of this pest. Herein, we describe plant volatile compounds (VOCs with repellent activity, and new findings about defence priming against spider mites, which interfere with the T. urticae performance. The use of VOCs and defence priming can be integrated into current management practices and reduce the damage caused by T. urticae in the field by implementing new, more sustainable crop management tools.

Toxicity of plant essential oils to Tetranychus urticae (Acari: Tetranychidae) and Phytoseiulus persimilis (Acari: Phytoseiidae).

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Choi, Won-Il; Lee, Sang-Geui; Park, Hyung-Man; Ahn, Young-Joon

2004-04-01

Fifty-three plant essential oils were tested for their toxicity against eggs and adults of Tetranychus urticae Koch as well as adults of Phytoseiulus persimilis Athias-Henriot, by using a filter paper diffusion bioassay without allowing direct contact. Responses varied according to oil type and dose, and mite species. In a plastic container (4.5 by 9.5 cm) bioassay at 14 x 10(-3) microl/ml air, caraway seed, citronella java, lemon eucalyptus, pennyroyal, and peppermint oils gave > 90% mortality against adult T. urticae, whereas 82 and 81% mortality was observed with sage and spearmint oils, respectively. With the exception of sage oil, the other six essential oils were highly effective against T. urticae eggs at 9.3 x 10(-3) microl/ml air. Against adult P. persimilis, these six test oils caused > 90% mortality at 7.1 x 10(-3) microl/ml air. Particularly peppermint oil at 4.7 x 10(-3) microl/ml air was highly toxic. In an acrylic cage (30 by 30 by 40 cm ) test, lemon eucalyptus, pennyroyal, peppermint, and spearmint oils were highly effective against adult T. urticae at 1.4 x 10(-3) microl/ml air. These results indicate that the mode of delivery of these essential oils was largely a result of action in the vapor phase via the respiratory system. The essential oils described herein merit further study as potential fumigants for T. urticae control.

The genome of Tetranychus urticae reveals herbivorous pest adaptations

NARCIS (Netherlands)

Grbić, M.; Van Leeuwen, T.; Clark, R.M.; Rombauts, S.; Grbić, V.; Osborne, E.J.; Dermauw, W.; Phuong, C.T.N.; Ortego, F.; Hernández-Crespo, P.; Diaz, I.; Martinez, M.; Navajas, M.; Sucena, E.; Magalhães, S.; Nagy, L.; Pace, R.M.; Djuranović, S.; Smagghe, G.; Iga, M.; Christiaens, O.; Veenstra, J.A.; Ewer, J.; Villalobos, R.M.; Hutter, J.L.; Hudson, S.D.; Velez, M.; Yi, S.V.; Zeng, J.; Pires-dasilva, A.; Roch, F.; Cazaux, M.; Navarro, M.; Zhurov, V.; Acevedo, G.; Bjelica, A.; Fawcett, J.A.; Bonnet, E.; Martens, C.; Baele, G.; Wissler, L.; Sanchez-Rodriguez, A.; Tirry, L.; Blais, C.; Demeestere, K.; Henz, S.R.; Gregory, T.R.; Mathieu, J.; Verdon, L.; Farinelli, L.; Schmutz, J.; Lindquist, E.; Feyereisen, R.; Van de Peer, Y.

2011-01-01

The spider mite Tetranychus urticae is a cosmopolitan agricultural pest with an extensive host plant range and an extreme record of pesticide resistance. Here we present the completely sequenced and annotated spider mite genome, representing the first complete chelicerate genome. At 90 megabases T.

Effect of gamma radiation on the toxicity of milbemectin and chlorfenapyr in acaricide resistant and susceptible strains of Tetranychus urticae Koch (Acari: Tetranychidae)

Energy Technology Data Exchange (ETDEWEB)

Nicastro, Roberto L.; Arthur, Valter; Machi, Andre R., E-mail: rnicastro@cena.usp.br, E-mail: arthur@cena.usp.br [Laboratorio de Radiobiologia e Ambiente (CENA/USP), Piracicaba, SP (Brazil); Sato, Mario E., E-mail: mesato@biologico.sp.gov.br [Laboratorio de Acarologia, Instituto Biologico, Campinas, SP (Brazil)

2011-07-01

The spider mite Tetranychus urticae Koch is considered one of the most important phytophagous mites, causing considerable damage in several agricultural crops. The aim of this study was to evaluate the effect of gamma radiation on the toxicity of the acaricides milbemectin and chlorfenapyr in resistant and susceptible strains of T. urticae. The R and S strains for milbemectin and chlorfenapyr were irradiated with gamma radiation at Gamma cell-220 source at doses of 5, 10, 20, 40 e 80 Gy. Five concentrations of milbemectin and chlorfenapyr were evaluated, making applications 24 hours after irradiation. Mites of the controls were sprayed with the same acaricide concentrations used for the R and S strains but they were not exposed to gamma radiation. Experiments on the effects of gamma radiation on the growth rates of mites for acaricide resistant and susceptible strains of T. urticae were also carried out. Tests with the Milbemectin S strain showed an increased susceptibility to the acaricide milbemectin, when the mites were irradiated (20 Gy), in comparison with the control (non irradiated mites). For the Milbemectin R strain, there was no significant influence of gamma irradiation on the toxicity of milbemectin to the mites of this strain. For the Chlorfenapyr S strain, the effect of gamma radiation was similar to that observed for Milbemectin S strain, with increased toxicity of chlorfenapyr to the mites of this susceptible strain. In the case of the Chlorfenapyr R strain, the mites exposed to gamma radiation showed to be more tolerant to chlorfenapyr, considering the LC{sub 10} values. The same trend was observed for the LC{sub 50} values, however, there was no significant difference with the control. The experiments showed that doses of 200 and 300 Gy eliminated the mite populations of acaricide resistant and susceptible strains of T. urticae, in a period of ten days. The dose of 100 Gy did not lead to total elimination of the mite populations, but reduced

Effect of gamma radiation on the toxicity of milbemectin and chlorfenapyr in acaricide resistant and susceptible strains of Tetranychus urticae Koch (Acari: Tetranychidae)

International Nuclear Information System (INIS)

Nicastro, Roberto L.; Arthur, Valter; Machi, Andre R.; Sato, Mario E.

2011-01-01

The spider mite Tetranychus urticae Koch is considered one of the most important phytophagous mites, causing considerable damage in several agricultural crops. The aim of this study was to evaluate the effect of gamma radiation on the toxicity of the acaricides milbemectin and chlorfenapyr in resistant and susceptible strains of T. urticae. The R and S strains for milbemectin and chlorfenapyr were irradiated with gamma radiation at Gamma cell-220 source at doses of 5, 10, 20, 40 e 80 Gy. Five concentrations of milbemectin and chlorfenapyr were evaluated, making applications 24 hours after irradiation. Mites of the controls were sprayed with the same acaricide concentrations used for the R and S strains but they were not exposed to gamma radiation. Experiments on the effects of gamma radiation on the growth rates of mites for acaricide resistant and susceptible strains of T. urticae were also carried out. Tests with the Milbemectin S strain showed an increased susceptibility to the acaricide milbemectin, when the mites were irradiated (20 Gy), in comparison with the control (non irradiated mites). For the Milbemectin R strain, there was no significant influence of gamma irradiation on the toxicity of milbemectin to the mites of this strain. For the Chlorfenapyr S strain, the effect of gamma radiation was similar to that observed for Milbemectin S strain, with increased toxicity of chlorfenapyr to the mites of this susceptible strain. In the case of the Chlorfenapyr R strain, the mites exposed to gamma radiation showed to be more tolerant to chlorfenapyr, considering the LC 10 values. The same trend was observed for the LC 50 values, however, there was no significant difference with the control. The experiments showed that doses of 200 and 300 Gy eliminated the mite populations of acaricide resistant and susceptible strains of T. urticae, in a period of ten days. The dose of 100 Gy did not lead to total elimination of the mite populations, but reduced significantly

Biological and ecological characterization of two mites (Tetranychus Urticae and Phytoseiulus Persimilis) occurring in some agro-ecosystems; Caratterizzazione biologica ed ecologica di due acari (Tetranichus Urticae e Phytoseiulus Persimilis) interagenti in alcuni ecosistemi agrari

Energy Technology Data Exchange (ETDEWEB)

Calvitti, M [ENEA, Centro Ricerche Casaccia, Roma (Italy). Dip. Innovazione

1995-12-01

This work is a brief review of the actual knowledge about biological and ecological characteristics of two species of mites: Tetranychus urticae Koch (Acarina Tetranychidae) (two-spotted spider mite) and the predaceous mite Phytoseiulus persimilis Athias Henriot (Acarina Phytoseiidae). Success obtained in biological control of spider mite, by mass release of P. persimilis, has increased the interest in biological and ecological study of these mites. Particularly, the following biological and ecological aspects of both P. persimilis and T. urticae are hereby discussed: reproductive biology; population dynamics (spider mites outbreaks) and natural regulation of the trophic interaction; feeding behaviour; biological control of two-spotted spider mite by P. persimilis. In this report experimental data obtained in laboratory have been integrated with bibliographic information concerning studies produced in natural conditions.

Greenhouse and field-based studies on the distribution of dimethoate in cotton and its effect on Tetranychus urticae by drip irrigation.

Science.gov (United States)

He, Jiangtao; Zhou, Lijuan; Yao, Qiang; Liu, Bo; Xu, Hanhong; Huang, Jiguang

2018-01-01

The two-spotted spider mite, Tetranychus urticae Koch is an important pest of cotton. We investigated the efficacy of dimethoate in controlling T. urticae by drip irrigation. Greenhouse and field experiments were carried out to determine the efficacy of dimethoate to T. urticae and the absorption and distribution of dimethoate in cotton. Greenhouse results showed that cotton leaves received higher amounts of dimethoate compared with cotton roots and stems, with higher amounts in young leaves compared with old leaves and cotyledon having the lowest amounts among leaves. Field results showed the efficacy of dimethoate to T. urticae by drip irrigation varied by volume of dripping water, soil pH and dimethoate dosage. Dimethoate applied at 3.00 kg ha -1 with 200 m 3  ha -1 water at weak acidic soil pH (5.70-6.70) through drip irrigation can obtain satisfactory control efficacy (81.49%, 7 days) to T. urticae, without negatively impacting on its natural enemy Neoseiulus cucumeris. The residue of dimethoate in all cotton seed samples were not detectable. These results demonstrate the effectiveness of applying dimethoate by drip irrigation for control of T. urticae on cotton. This knowledge could aid in the applicability of dimethoate by drip irrigation for field management of T. urticae populations. © 2017 Society of Chemical Industry. © 2017 Society of Chemical Industry.

Bazı Pestisitlerin Tetranychus urticae Koch'nin Ergin Yaşam Süresi ve Yumurta Verimine Etkileri

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Mustafa Hakan BALCI

2018-03-01

Full Text Available Bu çalışmada deltamethrin, cypermethrin, imidacloprid ve thiacloprid etkili maddeye sahip insektisitlerin tarla uygulama dozu (T ve tarla uygulama dozunun yarısı (T/2'nın uygulandığı Tetranychus urticae (Acari: Tetranychidae erginlerinde üreme parametreleri ve yaşam süreleri incelenmiştir. İnsektisit dozları ve kontrol grubunda kullanılan saf su ilaçlama kulesi ile Petri kabındaki yaprak diskler üzerinde bulunan T. urticae'nin ergin bireylerine uygulanmıştır. Deltamethrin'in T/2 dozu uygulaması sonucunda, ergin bireylerinde ortalama yaşam süresi (5.35 gün ve ortalama ovipozisyon süresi (4.29 g kontrol grubuna (6.57 ve 5.44 g göre kısalmış, ayrıca yumurta sayısı/dişi oranıda azalmıştır. İmidacloprid, thiacloprid ve cypermethrin uygulanan her iki dozunda da T. urticae erginlerinde ortalama yaşam süresi ve ortalama preovipozisyon süresi kontrol grubu ile istatistiki olarak benzer bulunmuş ve dozlar arasında fark belirlenememiştir. İmidacloprid'in T/2 dozu uygulanan ergin bireylerin yumurta sayısı/dişi (64.03 oranının kontrol grubuna (39.96 göre arttığı belirlenmiştir. Sonuç olarak, imidacloprid ve deltamethrin’in T/2 dozlarının T. urticae ergin bireylerinde ortalama yaşam süresi, ortalama ovipozisyon süresi gibi bazı biyolojik özelikler üzerinde etkili olabileceği kanısına varılmıştır. 

Effects of a mixture of vegetable and essential oils and fatty acid potassium salts on Tetranychus urticae and Phytoseiulus persimilis.

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Tsolakis, H; Ragusa, S

2008-06-01

Laboratory trials were carried out to evaluate the toxicity and the influence of a commercial mixture of vegetal, essential oils, and potassium salts of fatty acids (Acaridoil 13SL) on the population growth rate (r(i)--instantaneous rate of increase) of two mite species, the phytophagous Tetranychus urticae Koch and the predator Phytoseiulus persimilis Athias-Henriot. A residue of 1.3 mg/cm(2) of pesticide solution was harmless for Ph. persimilis eggs, while a moderate mortality of eggs and of larvae from treated eggs of T. urticae, was observed (53.8%). The pesticide also caused a delay in the postembryonic development of the tetranychid. Moreover, 83.4% mortality was reported for treated females tetranychids and only 24.0% for Ph. persimilis females. The pesticide influenced negatively the population growth of T. urticae which showed a very low rate of increase (r(i)=0.07), compared to that obtained in the control (r(i)=0.68). The pesticide did not affect negatively the reproductive potential of Ph. persimilis (r(i)=0.54 and r(i)=0.57 for test and control, respectively). These results suggest a considerable acaricidal activity of potassium salts of fatty acids and caraway oil on T. urticae and a good selectivity on Ph. persimilis.

Interactions in a tritrophic acarine predator-prey metapopulation system V: Within-plant dynamics of Phytoseiulus persimilis and Tetranychus urticae (Acari: Phytoseiidae, Tetranychidae)

DEFF Research Database (Denmark)

Nachman, Gösta; Zemek, Rostislav

2003-01-01

Biological control, Bottom-up factor, Phytoseiulus persimilis, Plant condition, Predacious mites, Simulation model, Tetranychus urticae, Top-down factor, Two-spotted spider mites......Biological control, Bottom-up factor, Phytoseiulus persimilis, Plant condition, Predacious mites, Simulation model, Tetranychus urticae, Top-down factor, Two-spotted spider mites...

Sublethal effects of spirodiclofen, abamectin and pyridaben on life-history traits and life-table parameters of two-spotted spider mite, Tetranychus urticae (Acari: Tetranychidae).

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Saber, Moosa; Ahmadi, Zeinab; Mahdavinia, Gholamreza

2018-05-01

Two-spotted spider mite, Tetranychus urticae Koch, is one of the economically most important pests on a wide range of crops in greenhouses and orchards worldwide. Control of T. urticae has been largely based on the use of acaricides. Sublethal effects of spirodiclofen, pyridaben and abamectin were studied on life-table parameters of T. urticae females treated with the acaricides. LC 25 values of spirodiclofen, abamectin and pyridaben (3.84, 0.04 and 136.96 µg a.i./ml, respectively) were used for sublethal studies. All acaricides showed significant effects on T. urticae biological parameters including developmental time, survival rate, and fecundity. The females treated with spirodiclofen, abamectin and pyridaben at LC 25 exhibited significantly reduced net reproductive rate (R 0 ), finite rate of increase (λ) and intrinsic rate of increase (r). The intrinsic rate of increase in spirodiclofen, abamectin and pyridaben treated groups and control were 0.0138, 0.0273, 0.039 and 0.2481 female offspring per female per day, respectively. The results indicated that sublethal concentrations of tested pesticides strongly affected the life characteristics of spider mite and consequently may influence mite population growth in future generations.

Mating competitiveness and the effect of X-rays and aging on males of Tetranychus urticae (Acarina, Tetranychidae) in relation to genetic control

International Nuclear Information System (INIS)

Feldmann, A.M.

1977-01-01

Males of Tetranychus urticae Koch were irradiated with X-ray doses of 4, 8, 24 and 32 krad (which were applied to 0-1 day-old adult virgin males) and tested in mating competition with one-day-old non-irradiated males. A non-significant excess of parental females were mated to the unirradiated males. This consistent trend in favour of females, mated with unirradiated males was highly significant, when the results of all the experiments were bulked. This indicated that radiation impaired the mating competitiveness of males of T. urticae. Aging of irradiated males resulted in a significant decrease of male-mating competitiveness at least within 2 days after irradiation. When 24 krad X-rays irradiated males were tested in mating competition at different ages, with unirradiated males of equal age, it was demonstrated that the reduction in mating competitiveness of aging irradiated males is caused by accelerated aging due to the irradiation treatment

Nouvelle technique d'élevage de l'acarien phyllophage Tetranychus urticae Koch (Acari : Tetranychidae et son application à l'étude de l'efficacité de quelques acaricides sur pomme de terre (Solarium tuberosum L.

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Badegana, AM.

2000-01-01

Full Text Available A New Rearing Technique of Phytophagous Mite Tetranychus urticae Koch (Acari : Tetranychida and its Application in the Study of the Efficacy of some Acaricides on Potato [Solanum tuberosum L.. A 5 cm diameter leaf disc of potato or another host plant (or four on 2.5 cm diameter was used in a Petri dish of 9 cm diameter for the rearing technique. This leaf disc, pierced in its centre, slides along a rustproof pin and floats on a 1 mm thick lamina of demineralized fresh water. Water is a "strong barrier" which confines the tetranychid mites on the leaf disc, even if this one does not corne from a host plant (tetranychid mites deprived of food. This rearing technique was used as a bioassay to test the effectiveness of acaricides (pyrimiphos-methyl, bromopropylate, fenpropathrin, dienochlor on the developmental stages of Tetranychus urticae. The ovicidal activity against the eggs of one, three, seven days old (the eggs incubation duration being 8.1 ±0.15 days was also studied. The results obtained show that bromopropylate, fenpropathrin and dienochlor have an ovicidal activity against the eggs of the different ages, but dienochlor has the highest efficiency (90 % mortality. Pyrimiphos-methyl is only active against the seven-day old eggs and bromopropylate has a high efficiency only on the one-day old eggs. Concerning the other developmental stages such as chrysalis (protochrysalis, deu-tochrysalis, teleiochrysalis and mobile stages (larva, protonymph, deutonymph and adult female, pyrimiphos-methyl has de highest efficiency (90 % mortality ; dienochlor also, except mobile stages. Bromopropylate has no activity against the chrysalis and mobile stages and fenpropathrin has a remarkable repulsive effect.

Low temperature–scanning electron microscopy to evaluate morphology and predation of Scolothrips sexmaculatus Pergande (Thysanoptera: Thripidae) against spider mites (Acari: Tetranychidae: Tetranychus species)

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This paper evaluates the potential usefulness of low temperature-scanning electron microscopy (LT-SEM) to evaluate morphology and predation behavior of the six-spotted thrips (Scolothrips sexmaculatus Pergande) against the two-spotted spider mite (Tetranychus urticae (Koch)). Morphological features...

Primeiro registro de Tetranychus urticae (Acari: Tetranychidae em mudas de teca no Brasil

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Alexandre dos Santos

2014-07-01

Full Text Available O ácaro fitófago Tetranychus urticae (Kock, 1836 (Acari: Tetranychidae foi relatado e suas injúrias caracterizadas pela primeira vez em viveiro de produção mudas de teca (Tectona grandis no Brasil.

CONFIRMATION OF PRESENCE OF A PREDATORY GALL MIDGE, Feltiella acarisuga, (Vallot, 1827 AND STAPHYLINID PREDATOR Oligota oviformis Casey, 1893 OF A TWO SPOTTED SPIDER MITE (Tetranychus urticae, Koch, 1836 IN SLOVENIA

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Katarina KOS

2018-04-01

Full Text Available The two spotted spider mite, Tetranychus urticae C. L. Koch, 1836 is one of the most important pests of greenhouse crops worldwide. Due to its polyphagic range of hosts and rapid development it forms great populations and as such represents a suitable host/prey for lots of natural enemies usable in biological control. Most commonly used predators of Tetranychid mites are predatory mites (Phytoseiulus persimilis Athias-Henriot, 1957, Amblyseius swirskii Athias-Henriot, 1962 ,…, but among most voracious predators is the larva of a predatory gall midge, Feltiella acarisuga (Vallot, 1827 that was found also in greenhouses of the Biotechnical Faculty in Ljubljana on eggplant leaves in 2017. Besides the predatory gall midge also another predator, staphylinid Oligota oviformis Casey, 1893 beetles and larvae were found in great numbers. After positive identification of F. acarisuga found naturally in Slovenia, it can be added to the list of indigenous species of natural enemies and thus can be used in biological control programs in greenhouse crop protection against spider mites.

Bioactivity of Licaria puchury-major Essential Oil Against Aedes aegypti , Tetranychus urticae and Cerataphis lataniae

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Sidney G. Azevedo

2018-05-01

Full Text Available The present study was carried out to evaluate an alternative controlling agent for greenhouse pests and the yellow fever mosquito larvae. The potential bioactivity of Licaria puchury-major (Mart. Kosterm. (“puxuri” was evaluated here against three most common pests in tropical and subtropical countries: Aedes aegypti Linn. Larvae, Tetranychus urticae Koch. mites and Cerataphis lataniae Boisd. aphids. The essential oil from seeds was analyzed by GC-FID and GC-MS. The major compounds were safrole (38.8% and eucalyptol (21.7%. Phenylpropanes (51.7% was the main group of compounds and oxygenated monoterpenes represented 28.8% of the total oil. The essential oil has shown no inhibition of acetylcholinesterase (AChE in the tested concentrations. However, potential antioxidant activities were evaluated by different methods [DPPH: LD 50 = (27.8 ± 1.0 µg/.mL; ABTS: (977.3 ± 25.2 µM TEs/g (Trolox Equivalents; FRAP: (548.2 ± 29.0 µM Fe(II/g]. A significant larvicidal potential for 24 h of exposure was observed with LD 50 = 98.9 µg/mL, being an indicative that the larval mortality may occur by ingestion or contact due to the no inhibition against AChE. Volatile phase effects were evaluated against T. urticae Koch. and C. lataniae Boisd. and LD 50 were found about 30.8 and 13.5 µg/mL , respectively. These results are consistent with an octopaminergic effect , since some phenylpropanoids (such as Safrole, identified as the major compound in this work can block octopamine, a multi-functional, naturally occurring biogenic amine. Then, this study clearly illustrated the efficacy of the investigated seeds, which encourages the development of a new potential natural controlling agent against these common pests due to the abundance of these seeds in the Amazon region and to the high essential oil yield .

Functional characterization of glutathione S-transferases associated with insecticide resistance in Tetranychus urticae

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Pavlidi, N.; Tseliou, V.; Riga, M.; Nauen, R.; Van Leeuwen, T.; Labrou, N.E.; Vontas, J.

2015-01-01

The two-spotted spider mite Tetranychus urticae is one of the most important agricultural pests world-wide. It is extremely polyphagous and develops resistance to acaricides. The overexpression of several glutathione S-transferases (GSTs) has been associated with insecticide resistance. Here, we

An analysis of potential resistance of the phytophagous mite, Tetranychus urticae Koch (Acari: Tetranychidae to four botanical pesticides

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Attia, S.

2015-01-01

Full Text Available Description of the subject. Synthetic acaricides have been widely used to manage Tetranychus urticae. Due to the excessive use of biocide and the associated problems of pesticide resistance and environmental pollution, there is an increasing demand for sustainable, environmentally-friendly control methods. Among the current alternative strategies aimed at decreasing the pest populations, the pesticides based on plant extracts are currently one of the most promising methods. Essential oils with acaricidal properties have been categorized as green pesticides because they are biodegradable and predominantly non-toxic to vertebrates. Objectives. With an aim to reduce the use of synthetic pesticides, they represent a promising approach for eco-chemical control of mites. Method. The aim of the present work was to analyze the risk of resistance emergence of T. urticae to repeated treatments with four plant extracts: Deverra scoparia Coss. & Durieu (Araliales: Apiaceae, Hertia cheirifolia (L. Kuntze (Asterales: Ateraceae, Santolina africana Jord. & Fourr. (Asterales: Asteraceae essential oils and garlic distillate Allium sativum L. (Asparagales: Alliaceae after 20 generations. Results. Repeated treatments with S. africana essential oil during 20 generations did not provoke an emergence of resistance while a low development of resistance was observed with H. cheirifolia, A. sativum and D. scoparia extracts. Conclusions. The efficacy of these extracts against the two spotted spider mite and their low development of resistance make them a promising use for pest management.

Life table and male mating competitiveness of wild type and of a chromosome mutation strain of Tetranychus urticae in relation to genetic pest control

International Nuclear Information System (INIS)

Feldmann, A.M.

1981-01-01

Males of Tetranychus urticae Koch (Acarina: Tetranychidae) from a strain, homozygous for a structural chromosome mutation (T) were competed against males from a standard (wild-type) strain for mating of wild-type fermales. The T-males exhibited only a slight reduction in male mating competitiveness. The debilitating influence of ageing on male mating competitiveness was equal for males of both strains. Life-table studies on both strains showed that the net reproductive rate (R 0 ) of the T-strain was 53.3, which was higher than the R 0 -value of the standard strain (43.3). This difference was caused by the higher rate of age-dependent mortality of adult females of the standard strain. Also differences between both strains in the total sex-ratio were observed; the T-strain produced significantly fewer males and more females than the standard strain. The mean generation time of both strains was almost equal (14 days). The values of the intrinsic rate of increase (rsub(m)) for the T-strain and the standard strain were 0.286 and 0.273, respectively. The life-table data correspond well with those published elsewhere on Tetranychus urticae. The feasibility of T-strains for application in genetic pest control considering the use of structural chromosome mutations as a 'transport mechanism' for conditional lethals is discussed. (orig.)

Integrated pest management of two-spotted mite Tetranychus urticae on greenhouse roses using petroleum spray oil and the predatory mite Phytoseiulus persimilis.

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Nicetic; Watson, D M; Beattie, G A; Meats, A; Zheng, J

2001-01-01

From 1995 to 1999, four experiments were conducted on greenhouse roses to assess the effectiveness of the nC24 petroleum spray oil (PSO), D-C-Tron Plus, against two-spotted mite, Tetranychus urticae Koch (Acarina: Tetranychidae), and to determine how the oil could be most efficiently and effectively used in combination with the predatory mite Phytoseiulus persimilis Athias-Henriot (Acarina: Phytoseiidae) in an integrated pest management program. The results showed that 0.5% PSO applied fortnightly to roses gave excellent protection from T urticae infestation when the mite population was not already established. However, PSO applied after roses were infested with T. urticae above the economic threshold only stabilised populations without reducing them below that threshold. Populations of P. persimilis in the upper and lower canopies were unchanged after two sprays of PSO at 7-day intervals, and application of PSO to the upper canopy was as effective in controlling T. urticae in the presence of P persimilis as spraying the entire plant. Combining PSO with P. persimilis gave better control of T. urticae than using P. persimilis alone. The most cost-effective use of PSO in the presence of P. persimilis is, therefore, to apply spray only to the upper canopy. This will not affect control of powdery mildew with PSO. Comparison of a control program for T urticae based on the monitored use of synthetic miticides with that based on calendar application of PSO revealed that both gave equally effective control. The benefits of combining PSO and P. persimilis in an integrated pest management program for T. urticae on roses over a program based on synthetic fungicides are discussed.

The preliminary assessment and isolation of entomopathogenic fungi to be used in biological control with twospotted spider mite [Tetranychus urticae (acari, tetranychidae)] from East Anatolia

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Örtücü, Serkan; Algur, Ömer Faruk

2017-04-01

This study was conducted to isolation entomopathogenic fungi for possible use in biocontrol of two-spotted spider mite Tetranychus urticae Koch. and to determine their pathogenicity. For this purpose, plant leaves infected with T. urticae were collected from Erzurum, Kars and Ardahan. At laboratory, the internal and external mycoflora of T.urticae individuals on plant leaves were determined. As a result of isolation, twenty-five different fungi species belonging to the genera Acremonium, Alternaria, Aspergillus, Beauveria, Cladosporium, Gliocladium, Humicola, Penicillium, Trichoderma, Isaria, Ulocladium and Verticillium were obtained. Pathogenicity of this forty-five isolate belonging to twenty-five species were evaluated. As a test organism, T. urticae was used and suspensions (1 × 108conidia ml-1) were prepared in Tween 80. 2ml suspension of a single dose was sprayed onto down side of bean leaf discs using hand sprayer. Mortality was recorded daily for 7 days. A total of twelve isolates belonging to three species were determined to be pathogen against T.urticae. According to scale used: AT020 Isaria farinosa and AT025 Cladosporium cladosporioides were determined as least pathogen, AT037 and AT101 Beauveria bassiana, and AT019 and AT026 C. cladosporioides, and AT035 and AT036 I. farinosa as moderate pathogen, AT007, AT021, AT034 and AT076 B. bassiana as highly pathogen. The other thirty-three isolates found that not pathogenic against T.urticae.

Characterization of spatial distribution of Tetranychus urticae in peppermint in California and implication for improving sampling plan.

Science.gov (United States)

Rijal, Jhalendra P; Wilson, Rob; Godfrey, Larry D

2016-02-01

Twospotted spider mite, Tetranychus urticae Koch, is an important pest of peppermint in California, USA. Spider mite feeding on peppermint leaves causes physiological changes in the plant, which coupling with the favorable environmental condition can lead to increased mite infestations. Significant yield loss can occur in absence of pest monitoring and timely management. Understating the within-field spatial distribution of T. urticae is critical for the development of reliable sampling plan. The study reported here aims to characterize the spatial distribution of mite infestation in four commercial peppermint fields in northern California using spatial techniques, variogram and Spatial Analysis by Distance IndicEs (SADIE). Variogram analysis revealed that there was a strong evidence for spatially dependent (aggregated) mite population in 13 of 17 sampling dates and the physical distance of the aggregation reached maximum to 7 m in peppermint fields. Using SADIE, 11 of 17 sampling dates showed aggregated distribution pattern of mite infestation. Combining results from variogram and SADIE analysis, the spatial aggregation of T. urticae was evident in all four fields for all 17 sampling dates evaluated. Comparing spatial association using SADIE, ca. 62% of the total sampling pairs showed a positive association of mite spatial distribution patterns between two consecutive sampling dates, which indicates a strong spatial and temporal stability of mite infestation in peppermint fields. These results are discussed in relation to behavior of spider mite distribution within field, and its implications for improving sampling guidelines that are essential for effective pest monitoring and management.

Acaricide resistance and resistance mechanisms in Tetranychus urticae populations from rose greenhouses in the Netherlands

NARCIS (Netherlands)

Khajehali, J.; Van Nieuwenhuyse, P.; Demaeght, P.; Tirry, L.; Van Leeuwen, T.

2011-01-01

BACKGROUND: Spider mites are important crop pests that rapidly develop resistance to acaricides. To investigate whether acaricide resistance is a threat to greenhouse rose culture in the Netherlands, the susceptibility of 15 strains of Tetranychus urticae was tested to several currently used

Atividade acaricida dos óleos essencias de folhas e frutos de Xylopia sericea sobre o ácaro rajado (Tetranychus urticae Koch Acaricidal activity of the essential oils leaves and fruits of Xylopia sericea St. Hill. on the two spotted spide mite (Tetranychus urticae Koch

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Wendel José Teles Pontes

2007-08-01

Full Text Available The essential oils of the leaves and fruits obtained by hydrodistillation of Xylopia sericea, collected in the restinga area of Pernambuco, were analyzed by GC (HP 5890 SERIES II and GC/MS (HP 5890B SERIES II/ MSD 5971. A major part of the volatile components identified in the oils of fruits and leaves were monoterpenes and sesquiterpenes. Cubenol (57.43% and alpha-epi-muurolol (26.09% were the main compounds found in the leaves, whereas beta-pinene (45.59% and alpha-pinene (17.18% were the fruits major components. The acaricidal activity of the essential oils was evaluated for Tetranychus urticae. The oil of the leaves was more active than that of the fruits showing an LC50 value of 4.08 µL/L of air for a 72 h period.

Plant-herbivore interaction: dissection of the cellular pattern of Tetranychus urticae feeding on the host plant

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Nicolas Bensoussan

2016-07-01

Full Text Available The two-spotted spider mite, Tetranychus urticae Koch (Acari: Tetranychidae, is one of the most polyphagous herbivores feeding on cell contents of over 1,100 plant species including more than 150 crops. It is being established as a model for chelicerate herbivores with tools that enable tracking of reciprocal responses in plant-spider mite interactions. However, despite their important pest status and a growing understanding of the molecular basis of interactions with plant hosts, knowledge of the way mites interface with the plant while feeding and the plant damage directly inflicted by mites is lacking. Here, utilizing histology and microscopy methods, we uncovered several key features of T. urticae feeding. By following the stylet path within the plant tissue, we determined that the stylet penetrates the leaf either in between epidermal pavement cells or through a stomatal opening, without damaging the epidermal cellular layer. Our recordings of mite feeding established that duration of the feeding event ranges from several minutes to more than half an hour, during which time mites consume a single mesophyll cell in a pattern that is common to both bean and Arabidopsis plant hosts. In addition, this study determined that leaf chlorotic spots, a common symptom of mite herbivory, do not form as an immediate consequence of mite feeding. Our results establish a cellular context for the plant-spider mite interaction that will support our understanding of the molecular mechanisms and cell signaling associated with spider mite feeding.

Efeitos do nim sobre tetranychus urticae Koch (Acari: Tetranychidae e os predadores Phytoseiulus macropilis (Banks e Neoseiulus californicus (Mcgregor (Acari: Phytoseiidae Effects of neem on tetranychus urticae Koch (Acari: Tetranychidae and the predators Phytoseiulus macropilis (Banks and Neoseiulus Californicus (Mcgregor (Acari: phytoseiidae

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Daniele Cristine Hoffmann Schlesener

2013-03-01

Full Text Available O objetivo deste trabalho foi avaliar a eficiência de controle e os efeitos adversos de dois produtos à base de nim Azamax® (Azadiractina A/B 12g/L e Neemseto® (Azadiractina A/B, Nimbina e Salanina 2,389 g/L sobre o ácaro-rajado Tetranychus urticae e os predadores Phytoseiulus macropilis e Neoseiulus californicus em laboratório. Para o ácaro-rajado, foram consideradas as variáveis mortalidade, fecundidade, efeito ovicida e persistência biológica, enquanto para os fitoseídeos consideraram-se mortalidade e fecundidade. A mortalidade máxima observada para o ácaro-rajado foi de 89,7% e 91,5% para Azamax® e Neemseto®, respectivamente, na concentração de 0,5% após a reaplicação do produto no sétimo dia. Também foram observados efeitos adversos sobre a fecundidade e a viabilidade dos ovos quando tratados com os produtos comerciais (p.c.. A persistência biológica dos produtos foi de aproximadamente três dias após a pulverização. As formulações apresentaram seletividade em relação aos fitoseídeos, porém causaram redução da fecundidade dos mesmos.The aim of the present study was to evaluate the efficiency of control and adverse effects of two neem based products: Azamax TM (Azadirachtin A/B 12g/L and Neemseto TM (Azadirachtin A/B, Nimbin and Salanin 2,389 g/L over two-spotted spider mite Tetranychus urticae and the predators Phytoseiulus macropilis and Neoseiulus californicus in laboratory. Effects over the mortality, fecundity, eggs and biological persistence of the two-spotted spider mite when treated with neem based products were evaluated. For the phytoseiids the effects on mortality and fecundity were evaluated. The maximum mortality of two-spotted spider mites rates observed were 89.7% and 91.5% for Azamax TM and Neemseto TM respectively, on the 0.5% concentration after reapplying the product on the seventh day. Adverse effects were also observed over the fecundity and viability of the eggs when treated with

Egg hatching response to a range of ultraviolet-B (UV-B) radiation doses for four predatory mites and the herbivorous spider mite Tetranychus urticae.

Science.gov (United States)

Koveos, Dimitrios S; Suzuki, Takeshi; Terzidou, Anastasia; Kokkari, Anastasia; Floros, George; Damos, Petros; Kouloussis, Nikos A

2017-01-01

Egg hatchability of four predatory mites-Phytoseiulus persimilis Athias-Henriot, Iphiseius [Amblyseius] degenerans Berlese, Amblyseius swirskii Athias-Henriot, and Euseius finlandicus Oudemans (Acari: Phytoseiidae)-and the spider mite Tetranychus urticae Koch (Acari: Tetranychidae) was determined under various UV-B doses either in constant darkness (DD) or with simultaneous irradiation using white light. Under UV-B irradiation and DD or simultaneous irradiation with white light, the predator's eggs hatched in significantly lower percentages than in the control non-exposed eggs, which indicates deleterious effects of UV-B on embryonic development. In addition, higher hatchability percentages were observed under UV-B irradiation and DD in eggs of the predatory mites than in eggs of T. urticae. This might be caused by a higher involvement of an antioxidant system, shield effects by pigments or a mere shorter duration of embryonic development in predatory mites than in T. urticae, thus avoiding accumulative effects of UV-B. Although no eggs of T. urticae hatched under UV-B irradiation and DD, variable hatchability percentages were observed under simultaneous irradiation with white light, which suggests the involvement of a photoreactivation system that reduces UV-B damages. Under the same doses with simultaneous irradiation with white light, eggs of T. urticae displayed higher photoreactivation and were more tolerant to UV-B than eggs of the predatory mites. Among predators variation regarding the tolerance to UV-B effects was observed, with eggs of P. persimilis and I. degenerans being more tolerant to UV-B radiation than eggs of A. swirskii and E. finlandicus.

Toxicity of the herbicide glufosinate-ammonium to predatory insects and mites of Tetranychus urticae (Acari: Tetranychidae) under laboratory conditions.

Science.gov (United States)

Ahn, Y J; Kim, Y J; Yoo, J K

2001-02-01

The toxicities of the herbicide glufosinate-ammonium to three predatory insect and two predatory mite species of Tetranychus urticae Koch were determined in the laboratory by the direct contact application. At a concentration of 540 ppm (a field application rate for weed control in apple orchards), glufosinate-ammonium was almost nontoxic to eggs of Amblyseius womersleyi Schicha, Phytoseiulus persimilis Athias-Henriot, and T. urticae but highly toxic to nymphs and adults of these three mite species, indicating that a common mode of action between predatory and phytophagous mites might be involved. In tests with predatory insects using 540 ppm, glufosinate-ammonium revealed little or no harm to larvae and pupae of Chrysopa pallens Rambur but was slightly harmful to eggs (71.2% mortality), nymphs (65.0% mortality), and adults (57.7% mortality) of Orius strigicollis Poppius. The herbicide showed no direct effect on eggs and adults of Harmonia axyridis (Pallas) but was harmful, slightly harmful, and harmless to first instars (100% mortality), fourth instars (51.1% mortality), and pupae (24.5% mortality), respectively. The larvae and nymphs of predators died within 12 h after treatment, suggesting that the larvicidal and nymphicidal action may be attributable to a direct effect rather than an inhibitory action of chitin synthesis. On the basis of our data, glufosinate-ammonium caused smaller effects on test predators than on T. urticae with the exception of P. persimilis, although the mechanism or cause of selectivity remains unknown. Glufosinate-ammonium merits further study as a key component of integrated pest management.

The role of horizontally transferred genes in the xenobiotic adaptations of the spider mite Tetranychus urticae

NARCIS (Netherlands)

Wybouw, N.R.

2015-01-01

Plant feeding arthropods adapt in diverse ways to dietary plant toxins. The genetic basis of these adaptations is not well characterized, especially in non-insect lineages. Using the sequenced genome of the herbivorous spider mite Tetranychus urticae as a starting point, this work aimed at

Antipredator responses in Tetranychus urticae differ with predator specialization

DEFF Research Database (Denmark)

Jacobsen, Stine Kramer; Alexakis, I.; Sigsgaard, Lene

2016-01-01

The behavioural response of Tetranychus urticae to chemical cues from specialist predatory mites, Phytoseiulus persimilis, or generalist predatory bugs, Orius majusculus, on either bean or strawberry was studied in experimental arenas. Predators were placed on the leaf disc for 24 h and removed...... and control treatments. No interaction effect was found between plant species and prey fecundity, while significantly more eggs were laid on bean than on strawberry. Predator cues irrespective of predator specialization resulted in more prey dispersal than in the control. Findings emphasize the importance...

Acaricidal activity and repellency of essential oil from Piper aduncum and its components against Tetranychus urticae.

Science.gov (United States)

Araújo, Mário J C; Câmara, Cláudio A G; Born, Flávia S; Moraes, Marcílio M; Badji, César A

2012-06-01

The chemical composition of essential oil of leaves of Piper aduncum L., growing wild in a fragment of the Atlantic Rainforest biome in northeastern Brazil, was determined through gas chromatography-mass spectrometry. The acaricidal activity and repellency of the essential oil and its components [dillapiole (0.28 g/ml), α-humulene (0.016 g/ml), (E)-nerolidol (0.0007 g/ml) and β-caryophyllene (0.0021 g/ml)] were evaluated in the laboratory against adults of Tetranychus urticae Koch. The mites were more susceptible to the oil in fumigation tests (LC(50) = 0.01 μl/l of air) than in contact test with closed Petri dish (LC(50) = 7.17 μl/ml); mortality was reduced by approximately 50 % in the latter test. The repellent action of the oil and toxicity by fumigation and contact did not differ significantly from the positive control (eugenol). The repellent activity was attributed to the components (E)-nerolidol, α-humulene and β-caryophyllene, whereas toxicity by fumigation and contact was attributed to β-caryophyllene. The effect of Piper oil and the role of its components regarding host plant preference with a two-choice leaf disk test are also discussed.

Attraction of Phytoseiulus persimilis (Acari: Phytoseiidae) towards volatiles from various Tetranychus urticae-infested plant species.

Science.gov (United States)

van den Boom, C E M; van Beek, T A; Dicke, M

2002-12-01

Plants infested with the spider mite Tetranychus urticae Koch, may indirectly defend themselves by releasing volatiles that attract the predatory mite Phytoseiulus persimilis Athias-Henriot. Several plants from different plant families that varied in the level of spider mite acceptance were tested in an olfactometer. The predatory mites were significantly attracted to the spider mite-infested leaves of all test plant species. No differences in attractiveness of the infested plant leaves were found for predatory mites reared on spider mites on the different test plants or on lima bean. Thus, experience with the spider mite-induced plant volatiles did not affect the predatory mites. Jasmonic acid was applied to ginkgo leaves to induce a mimic of a spider mite-induced volatile blend, because the spider mites did not survive when incubated on ginkgo. The volatile blend induced in ginkgo by jasmonic acid was slightly attractive to predatory mites. Plants with a high degree of direct defence were thought to invest less in indirect defence than plants with a low degree of direct defence. However, plants that had a strong direct defence such as ginkgo and sweet pepper, did emit induced volatiles that attracted the predatory mite. This indicates that a combination of direct and indirect defence is to some extent compatible in plant species.

Plant species modifies the functional response of Phytoseiulus persimilis (Acari: Phytoseiidae) to Tetranychus urticae (Acari: Tetranychidae): implications for biological control.

Science.gov (United States)

Skirvin, D J; Fenlon, J S

2001-02-01

The functional response of the predatory mite Phytoseiulus persimilis Athias-Henriot to eggs of its prey, the spider mite Tetranychus urticae Koch was examined on three plant species. Experiments were done to determine whether differences in the functional response on the three plant species were due to the morphological features of the crop directly on the predator or through an effect of the plant species on the prey. The results show that crop morphology is the only factor influencing the predatory ability of P. persimilis on the three plant species. Fewer eggs were eaten on Ceanothus thyrsiflorus var. 'Autumnal Blue', the plant species with hairy leaves, and greater numbers of prey consumed on Choisya ternata, a species with smooth leaves. However, similarly few eggs were eaten on the smooth, but waxy leaved Euonymus japonicus as on Ceanothus thyrsiflorus, demonstrating that morphological characters of leaves other than the possession of hairs and trichomes may affect the rates of predation. The implications of these results for the tritrophic interactions between plant, predator and prey, and the development of suitable biological control strategies are discussed.

Tomato whole genome transcriptional response to Tetranychus urticae identifies divergence of spider mite-induced responses between tomato and Arabidopsis

NARCIS (Netherlands)

Martel, C.; Zhurov, V.; Navarro, M.; Martinez, M.; Cazaux, M.; Auger, P.; Migeon, A.; Santamaria, M.E.; Wybouw, N.; Diaz, I.; Van Leeuwen, T.; Navajas, M.; Grbic, M.; Grbic, V.

2015-01-01

The two-spotted spider mite Tetranychus urticae is one of the most significant mite pests in agriculture, feeding on more than 1,100 plant hosts, including model plants Arabidopsis thaliana and tomato, Solanum lycopersicum. Here, we describe timecourse tomato transcriptional responses to spider mite

Tetranychus urticae Koch.

African Journals Online (AJOL)

Samson Edoja

2016-07-27

Jul 27, 2016 ... Simas NK, Lima EC, Conceição SR, Kuster RM, Filho AMO (2004). Natural products for control of dengue transmission – larvicidal activity of Myrozylon balsamum (red oil) and terpenoids and phenylpropanoids. Quim. Nova 27:46-49. Siqueira FFS, Oliveira JV, Ferraz CS, Oliveira CRF, Matos CHC (2014).

Tetranychus urticae mites do not mount an induced immune response against bacteria.

Science.gov (United States)

Santos-Matos, Gonçalo; Wybouw, Nicky; Martins, Nelson E; Zélé, Flore; Riga, Maria; Leitão, Alexandre B; Vontas, John; Grbić, Miodrag; Van Leeuwen, Thomas; Magalhães, Sara; Sucena, Élio

2017-06-14

The genome of the spider mite Tetranychus urticae , a herbivore, is missing important elements of the canonical Drosophila immune pathways necessary to fight bacterial infections. However, it is not known whether spider mites can mount an immune response and survive bacterial infection. In other chelicerates, bacterial infection elicits a response mediated by immune effectors leading to the survival of infected organisms. In T. urticae , infection by either Escherichia coli or Bacillus megaterium did not elicit a response as assessed through genome-wide transcriptomic analysis. In line with this, spider mites died within days even upon injection with low doses of bacteria that are non-pathogenic to Drosophila Moreover, bacterial populations grew exponentially inside the infected spider mites. By contrast, Sancassania berlesei , a litter-dwelling mite, controlled bacterial proliferation and resisted infections with both Gram-negative and Gram-positive bacteria lethal to T. urticae This differential mortality between mite species was absent when mites were infected with heat-killed bacteria. Also, we found that spider mites harbour in their gut 1000-fold less bacteria than S. berlesei We show that T. urticae has lost the capacity to mount an induced immune response against bacteria, in contrast to other mites and chelicerates but similarly to the phloem feeding aphid Acyrthosiphon pisum Hence, our results reinforce the putative evolutionary link between ecological conditions regarding exposure to bacteria and the architecture of the immune response. © 2017 The Authors.

Vitamin A deficiency modifies response of predatory mite Amblyseius potentillae to volatile kairomone of two-spotted spider mite, Tetranychus urticae.

NARCIS (Netherlands)

Dicke, M.; Sabelis, M.W.; Groeneveld, A.

1986-01-01

volatile kairomone of the two-spotted spider mite,Tetranychus urticae, elicits a searching response of the phytoseiid predatorAmblyseius potentillae, only when the predator is reared on a carotenoid-free diet. However, after addition of crystalline betta-carotene or vitamin A acetate to the

Olfactory response of Phytoseiulus persimilis (Acari: Phytoseiidae) to untreated and Beauveria bassiana-treated Tetranychus urticae (Acari: Tetranychidae).

Science.gov (United States)

Seiedy, Marjan; Saboori, Alireza; Zahedi-Golpayegani, Azadeh

2013-06-01

Determination of attraction and avoidance behavior of predators is important in concomitant use of multiple natural enemies to control a pest. The olfactory response of the predatory mite Phytoseiulus persimilis was studied to odors related to Tetranychus urticae adults infected by Beauveria bassiana DEBI008 in 0, 24, 48 and 72 h intervals, both in absence and in presence of plants. In plant-present experiments, P. persimilis attraction was neither towards adults of T. urticae infected by 0.02 % Tween 80 (as control), nor to the ones infected by B. bassiana for 0 or 24 h, whereas significant attraction towards the control was observed when tested against T. urticae infected by B. bassiana for 48 or 72 h. In absence of plants, P. persimilis displayed significant avoidance of T. urticae infected by B. bassiana for 48 or 72 h, when their alternative option was 0.02 % Tween 80-infected T. urticae adults. These results indicate that P. persimilis can recognize the presence of B. bassiana and that the predator avoids the fungus. This suggests that the two natural enemy species can be used together in biological control programmes.

Efficacy of Neoseiulus californicus and Phytoseiulus persimilis in suppression of Tetranychus urticae in young clementine plants.

Science.gov (United States)

Abad-Moyano, Raquel; Pina, Tatiana; Pérez-Panadés, Jordi; Carbonell, Emilio A; Urbaneja, Alberto

2010-04-01

Tetranychus urticae is one of the most damaging tetranychid mites affecting clementine orchards in Spain, where natural control is insufficient. Furthermore, in clementine nurseries, tender foliage is highly susceptible to attack and natural enemies are almost always absent. Therefore, acaricides are often used indiscriminately. Alternative control measures are necessary, both in commercial orchards and clementine nurseries. In order to assess the efficacy of inoculative releases of N. californicus and P. persimilis to reduce T. urticae populations in young Spanish clementine plants, a semi-field experiment was conducted and repeated in three seasons (spring, summer and autumn). Phytoseiulus persimilis was highly effective in reducing both T. urticae infestations and the damage level inflicted on plants at both release rates evaluated (40 and 80 phytoseiids/plant) and all three periods considered. By contrast, N. californicus demonstrated low performance under certain conditions. The results of this study could be adapted and transferred to nurseries and young citrus plantations.

The effect of chrysanthemum leaf trichome density and prey spatial distribution on predation of Tetranychus urticae (Acari: Tetranychidae) by Phytoseiulus persimilis (Acari: Phytoseiidae).

Science.gov (United States)

Skirvin, D J; Stavrinides, M C; Skirvin, D J

2003-08-01

The effect of plant architecture, in terms of leaf hairiness, and prey spatial arrangement, on predation rate of eggs of the spider mite, Tetranychus urticae Koch, by the predatory mite Phytoseiulus persimilis Athias-Henriot was examined on cut stems of chrysanthemums. Three levels of leaf hairiness (trichome density) were obtained using two different chrysanthemum cultivars and two ages within one of the cultivars. The number of prey consumed by P. persimilis was inversely related to trichome density. At low prey densities (less than ten eggs per stem), prey consumption did not differ in a biologically meaningful way between treatments. The effect of prey spatial arrangement on the predation rate of P. persimilis was also examined. Predation rates were higher in prey patches on leaves adjacent to the release point of P. persimilis, but significantly greater numbers of prey were consumed in higher density prey patches compared to low density patches. The predators exhibited non-random searching behaviour, spending more time on leaves closest to the release point. The implications of these findings for biological control and predator-prey dynamics are discussed.

Population density and phenology of Tetranychus urticae (Acari: Tetranychidae) in hop is linked to the timing of sulfur applications.

Science.gov (United States)

Woods, J L; Dreves, A J; Fisher, G C; James, D G; Wright, L C; Gent, D H

2012-06-01

The twospotted spider mite, Tetranychus urticae Koch, is a worldwide pest of numerous agronomic and horticultural plants. Sulfur fungicides are known to induce outbreaks of this pest on several crops, although mechanisms associated with sulfur-induced mite outbreaks are largely unknown. Studies were conducted during 2007-2009 in Oregon and Washington hop yards to evaluate the effect of timing of sulfur applications on T. urticae and key predators. In both regions, applications of sulfur made relatively late in the growing season (mid-June to mid-July) were associated with the greatest exacerbation of spider mite outbreaks, particularly in the upper canopy of the crop. The severity of mite outbreaks was closely associated with sulfur applications made during a relatively narrow time period coincident with the early exponential phase of spider mite increase and rapid host growth. A nonlinear model relating mean cumulative mite days during the time of sulfur sprays to the percent increase in total cumulative mite days (standardized to a nontreated plot) explained 58% of the variability observed in increased spider mite severity related to sulfur spray timing. Spatial patterns of spider mites in the Oregon plots indicated similar dispersal of motile stages of spider mites among leaves treated with sulfur versus nontreated leaves; however, in two of three years, eggs were less aggregated on leaves of sulfur-treated plants, pointing to enhanced dispersal. Apart from one experiment in Washington, relatively few predatory mites were observed during the course of these studies, and sulfur-induced mite outbreaks generally occurred irrespective of predatory mite abundance. Collectively, these studies indicate sulfur induces mite outbreaks through direct or indirect effects on T. urticae, mostly independent of predatory mite abundance or toxicity to these predators. Avoidance of exacerbation of spider mite outbreaks by sulfur sprays was achieved by carefully timing

Effects of azadirachtin on Tetranychus urticae (Acari: Tetranychidae) and its compatibility with predatory mites (Acari: Phytoseiidae) on strawberry.

Science.gov (United States)

Bernardi, Daniel; Botton, Marcos; da Cunha, Uemerson Silva; Bernardi, Oderlei; Malausa, Thibaut; Garcia, Mauro Silveira; Nava, Dori Edson

2013-01-01

The spider mite, Tetranychus urticae, is the major strawberry pest in Brazil. The main strategies for its control comprise synthetic acaricides and predatory mites. The recent register of a commercial formula of azadirachtin (Azamax(®) 12 g L(-1) ) can be viable for control of T. urticae. In this work, the effects of azadirachtin on T. urticae and its compatibility with predatory mites Neoseiulus californicus and Phytoseiulus macropilis in the strawberry crop were evaluated. Azadirachtin was efficient against T. urticae, with a mortality rate similar to that of abamectin. In addition, the azadirachtin showed lower biological persistence (7 days) than abamectin (21 days). Azadirachtin did not cause significant mortality of adult predatory mites (N. californicus and P. macropilis), but it did reduce fecundity by 50%. However, egg viability of the azadirachtin treatments was similar to that of the control (>80% viability). The use of azadirachtin and predatory mites is a valuable tool for controlling T. urticae in strawberry crop. Azadirachtin provided effective control of T. urticae and is compatible with the predatory mites N. californicus and P. macropilis. It is an excellent tool to be incorporated into integrated pest management for strawberry crop in Brazil. Copyright © 2012 Society of Chemical Industry.

Functional responses and prey-stage preferences of a predatory gall midge and two predacious mites wtih twospotted spider mites, Tetranychus urticae as host

Science.gov (United States)

The twospotted spider mite, Tetranychus urticae (Acari: Tetranychidae), is an important pest of vegetables and other crops. This study was conducted to evaluate and compare the potential role of three commercially available predators, predatory gall midge, Feltiella acarisuga (Vallot) (Diptera: Ceci...

Abamectin is metabolized by CYP392A16, a cytochrome P450 associated with high levels of acaricide resistance in Tetranychus urticae

NARCIS (Netherlands)

Riga, M.; Tsakireli, D.; Ilias, A.; Morou, E.; Myridakis, A.; Stephanou, E.G.; Nauen, R.; Dermauw, W.; Van Leeuwen, T.; Paine, M.; Vontas, J.

2014-01-01

Abamectin is one of the most important insecticides worldwide. It is used against major agricultural pests and insects of public health importance, as well as against endoparasites in animal health. Abamectin has been used successfully for the control of the spider mite Tetranychus urticae, a major

The effects of prey patchiness, predator aggregation, and mutual interference on the functional response of Phytoseiulus persimilis feeding on Tetranychus urticae (Acari: Phytoseiidae, Tetranychidae)

DEFF Research Database (Denmark)

Nachman, Gösta

2006-01-01

The spatial distributions of two-spotted spider mites Tetranychus urticae and their natural enemy, the phytoseiid predator Phytoseiulus persimilis, were studied on six full-grown cucumber plants. Both mite species were very patchily distributed and P. persimilis tended to aggregate on leaves...

Pre-adult development of Phytoseiulus persimilis on diets of Tetranychus urticae and Tetranychus lintearius: implications for the biological control of Ulex europaeus.

Science.gov (United States)

Davies, Jamie T; Ireson, John E; Allen, Geoff R

2009-02-01

Predation by the phytoseiid mite, Phytoseiulus persimilis, is considered a major threat to the effectiveness of biological control of gorse, Ulex europaeus, using Tetranychus lintearius. To assess this threat and to determine if the impact of P. persimilis on T. lintearius populations is comparable to its impact on T. urticae populations, its development and predator : prey generation time ratios were assessed. The pre-adult mortality and development time of two populations of P. persimilis fed on two diets, T. urticae and T. lintearius, were determined at two temperatures, 14 and 24 degrees C. There were no significant differences in either mortality or development time between the two populations of P. persimilis at these temperatures. There is therefore no evidence that the two tested populations of P. persimilis are behaving as different strains. Similarly, diet had no significant effect on either mortality or development time at these temperatures. At 14 degrees C the mortality of P. persimilis was significantly higher and development was significantly longer than at 24 degrees C. Using pre-adult development as a surrogate for generation times, predator : prey generation time ratios were calculated between P. persimilis and both T. urticae and T. lintearius using data from this and other studies. The predator : prey generation time ratios between P. persimilis and T. lintearius were lower than those between P. persimilis and T. urticae. These results indicate that the impact of P. persimilis on T. lintearius populations is likely to be comparable to its impact on T. urticae populations. This provides further evidence that predation by P. persimilis is having a deleterious effect on T. lintearius populations and therefore reducing its effectiveness as a biological control agent for gorse.

A horizontally transferred cyanase gene in the spider mite Tetranychus urticae is involved in cyanate metabolism and is differentially expressed upon host plant chang

NARCIS (Netherlands)

Wybouw, N.; Balabanidou, V.; Ballhorn, D.J.; Dermauw, W.; Grbić, M.; Vontas, J.; Van Leeuwen, T.

2012-01-01

The genome of the phytophagous two-spotted spider mite Tetranychus urticae was recently sequenced, representing the first complete chelicerate genome, but also the first genome of a highly polyphagous agricultural pest. Genome analysis revealed the presence of an unexpected high number of cases of

Effect Of Agrotechnical Measures And Varieties On Seasonal Dynamics Of Tetranychus Urticae Koch (Acari, Trombidiformes, Tetranychidae On High Tunnel-Cultivated Garden Strawberries

Directory of Open Access Journals (Sweden)

Salmane Ineta

2015-04-01

Full Text Available The aim of the present study was to determine the seasonal pattern of two-spotted spider mite Tetranychus urticae on strawberries cultivated in polythene-covered high tunnels in temperate climatic conditions. Various cultivars were used and the effect of modification of plant covering indices on abundance and incidence of these mites was also tested. The number of two-spotted spider mites was relatively low at the beginning of the vegetation season and started to increase when average air temperature rose above 20 to 25 °C. In the experiment two types of tunnels differing in additional plant cover were used. The maximum mite abundance did not significantly vary between varieties in tunnel 1 conditions, but it was significantly lower for variety 'Sonata' in tunnel 2 conditions. Mite numbers significantly declined after strawberry foliage mowing and removal of polythene cover. Mite development was prolonged in tunnel 1, where additional cover of plants was used and higher early season air temperature was recorded in comparison to tunnel 2. It was concluded that increase in early season temperature can increase two-spotted spider mite abundance and have a more negative effect on strawberry plants in respect of foliage damage by mites.

Efeitos do nim sobre tetranychus urticae Koch (Acari: Tetranychidae e os predadores Phytoseiulus macropilis (Banks e Neoseiulus californicus (Mcgregor (Acari: Phytoseiidae

Directory of Open Access Journals (Sweden)

Daniele Cristine Hoffmann Schlesener

2013-03-01

Full Text Available O objetivo deste trabalho foi avaliar a eficiência de controle e os efeitos adversos de dois produtos à base de nim Azamax® (Azadiractina A/B 12g/L e Neemseto® (Azadiractina A/B, Nimbina e Salanina 2,389 g/L sobre o ácaro-rajado Tetranychus urticae e os predadores Phytoseiulus macropilis e Neoseiulus californicus em laboratório. Para o ácaro-rajado, foram consideradas as variáveis mortalidade, fecundidade, efeito ovicida e persistência biológica, enquanto para os fitoseídeos consideraram-se mortalidade e fecundidade. A mortalidade máxima observada para o ácaro-rajado foi de 89,7% e 91,5% para Azamax® e Neemseto®, respectivamente, na concentração de 0,5% após a reaplicação do produto no sétimo dia. Também foram observados efeitos adversos sobre a fecundidade e a viabilidade dos ovos quando tratados com os produtos comerciais (p.c.. A persistência biológica dos produtos foi de aproximadamente três dias após a pulverização. As formulações apresentaram seletividade em relação aos fitoseídeos, porém causaram redução da fecundidade dos mesmos.

Intraguild interactions between Euseius stipulatus and the candidate biocontrol agents of Tetranychus urticae in Spanish clementine orchards: Phytoseiulus persimilis and Neoseiulus californicus.

Science.gov (United States)

Abad-Moyano, Raquel; Urbaneja, Alberto; Schausberger, Peter

2010-01-01

Spanish clementine orchards are frequently infested by the two-spotted spider mte Tetranychus urticae. Natural control of T. urticae is insufficient despite the presence of Neoseiulus californicus and Phytoseiulus persimilis. The phytoseiid community is dominated by the generalist Euseius stipulatus which is poorly adapted to exploit T. urticae. Having the intention to promote biological control of T. urticae by augmentative releases we were interested whether P. persimilis and N. californicus are negatively affected by intraguild (IG) interactions with E. stipulatus. Two experiments were conducted. Firstly, we assessed female aggressiveness (quantified as combination of attack probability and latency) in IG predation on larvae. Secondly, we measured mortality, escaping rate and developmental time of immature IG prey in presence and absence of an adult IG predator female. Euseius stipulatus appeared the strongest IG opponent but microhabitat structure modulated the IG interactions and the advantage of E. stipulatus was partially offset when spider mite webbing was present. Implications of these IG interactions for natural and biological control of T. urticae in clementine orchards are discussed.

Toxicidade de compostos sintéticos e naturais sobre Tetranychus urticae e o predador Phytoseiulus macropilis

Directory of Open Access Journals (Sweden)

Bruce Veronez

2012-04-01

Full Text Available O objetivo deste trabalho foi avaliar a toxicidade de compostos sintéticos e naturais sobre Tetranychus urticae e o predador Phytoseiulus macropilis. A mortalidade e a taxa de crescimento de T. urticae e seu predador foram avaliadas após a aplicação de: abamectina, clofentezina, fenpropatrina, fenpiroximato, propargito, enxofre e espiromesifeno, nas concentrações recomendadas; óleos de nim (Natuneem e Sempre Verde Killer Neem a 1%; e extratos aquosos a 10% de Dieffenbachia brasiliensis, Annona squamosa, Ruta graveolens, Agave angustifolia, Melia azedarach, Sonchus oleraceus, Mentha spicata x M. suaveolens, Allium cepa, Laurus nobilis e Eucalyptus saligna. A toxicidade aguda e a influência dos compostos sobre a taxa de crescimento instantâneo dos ácaros foram avaliadas em laboratório. Extratos de A. cepa, A. angustifolia, produtos à base de óleo de nim, espiromesifeno, propargito, fenpiroximato, abamectina e fenpropatrina causaram mortalidade superior a 83% em T. urticae. Extrato de A. angustifolia, Natuneem e clofentezina não causaram mortalidade significativa em P. macropilis. Agave angustifolia e Natuneem não afetaram significativamente a taxa de crescimento deste predador. Propargito, fenpiroximato, abamectina, fenpropatrina, espiromesifeno e extrato de L. nobilis afetaram severamente a população de P. macropilis.

A burst of ABC genes in the genome of the polyphagous spider mite Tetranychus urticae.

Science.gov (United States)

Dermauw, Wannes; Osborne, Edward John; Clark, Richard M; Grbić, Miodrag; Tirry, Luc; Van Leeuwen, Thomas

2013-05-10

The ABC (ATP-binding cassette) gene superfamily is widespread across all living species. The majority of ABC genes encode ABC transporters, which are membrane-spanning proteins capable of transferring substrates across biological membranes by hydrolyzing ATP. Although ABC transporters have often been associated with resistance to drugs and toxic compounds, within the Arthropoda ABC gene families have only been characterized in detail in several insects and a crustacean. In this study, we report a genome-wide survey and expression analysis of the ABC gene superfamily in the spider mite, Tetranychus urticae, a chelicerate ~ 450 million years diverged from other Arthropod lineages. T. urticae is a major agricultural pest, and is among of the most polyphagous arthropod herbivores known. The species resists a staggering array of toxic plant secondary metabolites, and has developed resistance to all major classes of pesticides in use for its control. We identified 103 ABC genes in the T. urticae genome, the highest number discovered in a metazoan species to date. Within the T. urticae ABC gene set, all members of the eight currently described subfamilies (A to H) were detected. A phylogenetic analysis revealed that the high number of ABC genes in T. urticae is due primarily to lineage-specific expansions of ABC genes within the ABCC, ABCG and ABCH subfamilies. In particular, the ABCC subfamily harbors the highest number of T. urticae ABC genes (39). In a comparative genomic analysis, we found clear orthologous relationships between a subset of T. urticae ABC proteins and ABC proteins in both vertebrates and invertebrates known to be involved in fundamental cellular processes. These included members of the ABCB-half transporters, and the ABCD, ABCE and ABCF families. Furthermore, one-to-one orthologues could be distinguished between T. urticae proteins and human ABCC10, ABCG5 and ABCG8, the Drosophila melanogaster sulfonylurea receptor and ecdysone-regulated transporter E

Tabla de vida y parámetros poblacionales fundamentales de Tetranychus urticae koch (Acari: tetranychidae sobre rosa Sp. en condiciones de laboratorio

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Páramo Gabriel

1986-12-01

Full Text Available Uno de los ácaros más ampliamente distribuidos y que causan pérdidas en cultivos bajo Invernadero en la Sabana de Bogotá es T. urt/ca8 Koch. Utilizando la técnica del disco de hoja con follaje de rosa se determinó el ciclo de vida de esta especie y se elaboró la tabla de vida. El experimento se mantuvo en condiciones ambientales controladas con una temperatura de 23 ± 2°C y humedad relativa de 85 ± 5%. La duración de los diferentes estadios fue: Huevo 7.39 dlas, larva 1.87, nlnfocrlsállda 1.57, protonlnfa 1.53, deutocrlsállda 1.52, deutonlnfa 1.73 y tellocrlsállda 1.84 dlas. El periodo de ovlposición fue de 35 días con un promedio de 3.52
huevos/hembra/día. Se construyó la curva de supervlvlencla para todo el ciclo de vida y se calcularon algunos parámetros poblaclonales tales como tasa neta de reproducción (Ro' tiempo medio generacional (T, tasa Intrinseca de crecimiento natural (rrn, tasa finita de multiplicación (A y distribución estable de edades.The two spotted spider mite, tetrenychus urticae Koch is one of the most widely dlstributed mites in the world and one of the maln causes of losses in commercial greenhouses in Bogota. Using the leaf dlsc technique some basic biologlcal data were studied under laboratory conditions with a temperature of 23 ±2°C and a relative humidlly of 85 ± 5%. Life cycle was
determined uslng rose leaves as host plant. Ovlposition time for females was 35 days with an average of 3.52 eggs per female per day. Net reproductlve rate (Ro, mean length of a generation
(T, Intrinsic rate of natural increase (r..,.,, finite rate of reproduction ('A and stable age distribution were calculated.

Overexpression of HvIcy6 in Barley Enhances Resistance against Tetranychus urticae and Entails Partial Transcriptomic Reprogramming

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M. Estrella Santamaria

2018-03-01

Full Text Available Cystatins have been largely used for pest control against phytophagous species. However, cystatins have not been commonly overexpressed in its cognate plant species to test their pesticide capacity. Since the inhibitory role of barley HvCPI-6 cystatin against the phytophagous mite Tetranychus urticae has been previously demonstrated, the purpose of our study was to determine if barley transgenic lines overexpressing its own HvIcy6 gene were more resistant against this phytophagous infestation. Besides, a transcriptomic analysis was done to find differential expressed genes among wild-type and transformed barley plants. Barley plants overexpressing HvIcy6 cystatin gene remained less susceptible to T. urticae attack when compared to wild-type plants, with a significant lesser foliar damaged area and a lower presence of the mite. Transcriptomic analysis revealed a certain reprogramming of cellular metabolism and a lower expression of several genes related to photosynthetic activity. Therefore, although caution should be taken to discard potential deleterious pleiotropic effects, cystatins may be used as transgenes with impact on agricultural crops by conferring enhanced levels of resistance to phytophagous pests.

Assessment of the interactions between two predator mites of Tetranychus urticae (Acariformes: Tetranychidae in laboratory

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Angelica María Argüelles

2013-01-01

Full Text Available Tetranychus urticae (Acari: Tetranychidae is one of the most important pests in ornamental cultures. Between the species most used for its control are Neoseilus sp. and Phytoseiulus persimilis (Acari: Phytoseiidae. Knowing the effectivity and ages of the prefers prey of each species of predator. In this search purposed the management of the plague through the use of combined releases, is necessary to evaluate that could occur between them with the prey when they act together. With this aim, we evaluated any situations. For one side was evaluated when a predator with a second predator with more density for the first predator. This situation was analyzed in presence and with absence of its prey. For other side, was evaluated the interactions of both predators are presents at the same density and with the prey. In the fist situation in presence of the prey was observe that increase the age of predator in minor density also increase the interference over the consumption of the high population’s predator over the prey. Moreover when decreased the T. urticae’s consumption increased the intraguild consumption. P. persimilis in absence of T. urticae and in presence of N. californicus approve a behavior of intraguild predation over all the ages of its cospecifics, while that N. californicus only consumed coespecific’s larvae in the phytofagous absence and in presence of  P. persimilis.  When both predators were in the same test at the same population’s density, was not observe a higher consumption of T. urticae that when each predator act for its way.

Tri-trophic level impact of host plant linamarin and lotaustralin on Tetranychus urticae and its predator Phytoseiulus persimilis.

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Rojas, M Guadalupe; Morales-Ramos, Juan Alfredo

2010-12-01

The impact of linamarin and lotaustralin content in the leaves of lima beans, Phaseolus lunatus L., on the second and third trophic levels was studied in the two-spotted spider mite, Tetranychus urticae (Koch), and its predator Phytoseiulus persimilis Athias-Henriot. The content of linamarin was higher in terminal trifoliate leaves (435.5 ppm) than in primary leaves (142.1 ppm) of Henderson bush lima beans. However, linamarin concentrations were reversed at the second trophic level showing higher concentrations in spider mites feeding on primary leaves (429.8 ppm) than those feeding on terminal trifoliate leaves (298.2 ppm). Concentrations of linamarin in the predatory mites were 18.4 and 71.9 ppm when feeding on spider mites grown on primary and terminal leaves, respectively. The concentration of lotaustralin in primary lima bean leaves was 103.12 ppm, and in spider mites feeding on these leaves was 175.0 ppm. Lotaustralin was absent in lima bean terminal trifoliate leaves and in mites feeding on these leaves. Fecundity of spider mites feeding on lima bean leaves (primary or trifoliate) was not significantly different from mites feeding on red bean, Phaseolus vulgaris L., primary leaves. However, the progeny sex ratio (in females per male) of spider mites feeding on lima bean leaves was significantly lower than progeny of spider mites feeding on red bean leaves (control). Fecundity and progeny sex ratio of P. persimilis were both significantly affected by the concentration of linamarin present in the prey. Changes in concentration of linamarin in living tissue across the three trophic levels are discussed.

From repulsion to attraction: species- and spatial context-dependent threat sensitive response of the spider mite Tetranychus urticae to predatory mite cues

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Fernández Ferrari, M. Celeste; Schausberger, Peter

2013-06-01

Prey perceiving predation risk commonly change their behavior to avoid predation. However, antipredator strategies are costly. Therefore, according to the threat-sensitive predator avoidance hypothesis, prey should match the intensity of their antipredator behaviors to the degree of threat, which may depend on the predator species and the spatial context. We assessed threat sensitivity of the two-spotted spider mite, Tetranychus urticae, to the cues of three predatory mites, Phytoseiulus persimilis, Neoseiulus californicus, and Amblyseius andersoni, posing different degrees of risk in two spatial contexts. We first conducted a no-choice test measuring oviposition and activity of T. urticae exposed to chemical traces of predators or traces plus predator eggs. Then, we tested the site preference of T. urticae in choice tests, using artificial cages and leaves. In the no-choice test, T. urticae deposited their first egg later in the presence of cues of P. persimilis than of the other two predators and cue absence, indicating interspecific threat-sensitivity. T. urticae laid also fewer eggs in the presence of cues of P. persimilis and A. andersoni than of N. californicus and cue absence. In the artificial cage test, the spider mites preferred the site with predator traces, whereas in the leaf test, they preferentially resided on leaves without traces. We argue that in a nonplant environment, chemical predator traces do not indicate a risk for T. urticae, and instead, these traces function as indirect habitat cues. The spider mites were attracted to these cues because they associated them with the existence of a nearby host plant.

A massive incorporation of microbial genes into the genome of Tetranychus urticae, a polyphagous arthropod herbivore.

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Wybouw, N; Van Leeuwen, T; Dermauw, W

2018-06-01

A number of horizontal gene transfers (HGTs) have been identified in the spider mite Tetranychus urticae, a chelicerate herbivore. However, the genome of this mite species has at present not been thoroughly mined for the presence of HGT genes. Here, we performed a systematic screen for HGT genes in the T. urticae genome using the h-index metric. Our results not only validated previously identified HGT genes but also uncovered 25 novel HGT genes. In addition to HGT genes with a predicted biochemical function in carbohydrate, lipid and folate metabolism, we also identified the horizontal transfer of a ketopantoate hydroxymethyltransferase and a pantoate β-alanine ligase gene. In plants and bacteria, both genes are essential for vitamin B5 biosynthesis and their presence in the mite genome strongly suggests that spider mites, similar to Bemisia tabaci and nematodes, can synthesize their own vitamin B5. We further show that HGT genes were physically embedded within the mite genome and were expressed in different life stages. By screening chelicerate genomes and transcriptomes, we were able to estimate the evolutionary histories of these HGTs during chelicerate evolution. Our study suggests that HGT has made a significant and underestimated impact on the metabolic repertoire of plant-feeding spider mites. © 2018 The Royal Entomological Society.

African Journal of Biotechnology - Vol 15, No 30 (2016)

African Journals Online (AJOL)

Tetranychus urticae Koch.) in peanut · EMAIL FREE FULL TEXT EMAIL FREE FULL TEXT DOWNLOAD FULL TEXT DOWNLOAD FULL TEXT. Maria Isabel G. Martins, Antonio Euzébio G. Sant'Ana, Felipe Matheus T. Vasconcelos, Wbyratan L. Silva, ...

Fundamental aspects of genetic control of the two-spotted spider mite Tetranychus urticae (Acari: Tetranychidae)

International Nuclear Information System (INIS)

Feldmann, A.M.

1979-01-01

Radiobiological properties of Tetranychus urticae and other topics of genetic control have been evaluated. The induction by X-rays or fast neutrons of dominant lethals in mature sperm and of dominant lethals and recessive lethals in prophase-1 oocytes and the induction by both radiation types of chromosome mutations, recessive lethals and factors causing F 1 -infertility in sperm and oocytes, have been studied. From the results the optimal dose, radiation type and germ cell type could be chosen for obtaining either fully sterile males or substerile males, producing fully infertile F 1 -females. Also the most favourable conditions were determined for the induction of chromosome mutations with the lowest frequency of linked recessive lethals. The radiobiological properties of holokinetic chromosomes are extensively discussed. The successful displacement of the standard karyotype by a radiation arranged karyotype is presented and discussed in its relevance for practical application. (Auth./C.F.)

Protocols for the delivery of small molecules to the two-spotted spider mite, Tetranychus urticae.

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Takeshi Suzuki

Full Text Available The two-spotted spider mite, Tetranychus urticae, is a chelicerate herbivore with an extremely wide host range and an extraordinary ability to develop pesticide resistance. Due to its responsiveness to natural and synthetic xenobiotics, the spider mite is becoming a prime pest herbivore model for studies of the evolution of host range, plant-herbivore interactions and mechanisms of xenobiotic resistance. The spider mite genome has been sequenced and its transcriptional responses to developmental and various biotic and abiotic cues have been documented. However, to identify biological and evolutionary roles of T. urticae genes and proteins, it is necessary to develop methods for the efficient manipulation of mite gene function or protein activity. Here, we describe protocols developed for the delivery of small molecules into spider mites. Starting with mite maintenance and the preparation of the experimental mite populations of developmentally synchronized larvae and adults, we describe 3 methods for delivery of small molecules including artificial diet, leaf coating, and soaking. The presented results define critical steps in these methods and demonstrate that they can successfully deliver tracer dyes into mites. Described protocols provide guidelines for high-throughput setups for delivery of experimental compounds that could be used in reverse genetics platforms to modulate gene expression or protein activity, or for screens focused on discovery of new molecules for mite control. In addition, described protocols could be adapted for other Tetranychidae and related species of economic importance such as Varroa, dust and poultry mites.

Interactions in a tritrophic acarine predator-prey metapopulation system V: within-plant dynamics of Phytoseiulus persimilis and Tetranychus urticae (Acari: Phytoseiidae, Tetranychidae).

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Nachman, Gösta; Zemek, Rostislav

2003-01-01

To investigate the relative contributions of bottom-up (plant condition) and top-down (predatory mites) factors on the dynamics of the two-spotted spider mite (Tetranychus urticae), a series of experiments were conducted in which spider mites and predatory mites were released on bean plants. Plants inoculated with 2, 4, 8, 16, and 32 adult female T. urticae were either left untreated or were inoculated with 3 or 5 adult female predators (Phytoseiulus persimilis) one week after the introduction of spider mites. Plant area, densities of T. urticae and P. persimilis, and plant injury were assessed by weekly sampling. Data were analysed by a combination of statistical methods and a tri-trophic mechanistic simulation model partly parameterised from the current experiments and partly from previous data. The results showed a clear effect of predators on the density of spider mites and on the plant injury they cause. Plant injury increased with the initial number of spider mites and decreased with the initial number of predators. Extinction of T. urticae, followed by extinction of P. persimilis, was the most likely outcome for most initial combinations of prey and predators. Eggs constituted a relatively smaller part of the prey population as plant injury increased and of the predator population as prey density decreased. We did not find statistical evidence of P. persimilis having preference for feeding on T. urticae eggs. The simulation model demonstrated that bottom-up and top-down factors interact synergistically to reduce the density of spider mites. This may have important implications for biological control of spider mites by means of predatory mites.

Hot-spot application of biocontrol agents to replace pesticides in large scale commercial rose farms in Kenya

DEFF Research Database (Denmark)

Gacheri, Catherine; Kigen, Thomas; Sigsgaard, Lene

2015-01-01

Rose (Rosa hybrida L.) is the most important ornamental crop in Kenya, with huge investments in pest management. We provide the first full-scale, replicated experiment comparing cost and yield of conventional two-spotted spider mite (Tetranychus urticae Koch) control with hot-spot applications of...

A Gene Family Coding for Salivary Proteins (SHOT) of the Polyphagous Spider Mite Tetranychus urticae Exhibits Fast Host-Dependent Transcriptional Plasticity.

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Jonckheere, Wim; Dermauw, Wannes; Khalighi, Mousaalreza; Pavlidi, Nena; Reubens, Wim; Baggerman, Geert; Tirry, Luc; Menschaert, Gerben; Kant, Merijn R; Vanholme, Bartel; Van Leeuwen, Thomas

2018-01-01

The salivary protein repertoire released by the herbivorous pest Tetranychus urticae is assumed to hold keys to its success on diverse crops. We report on a spider mite-specific protein family that is expanded in T. urticae. The encoding genes have an expression pattern restricted to the anterior podocephalic glands, while peptide fragments were found in the T. urticae secretome, supporting the salivary nature of these proteins. As peptide fragments were identified in a host-dependent manner, we designated this family as the SHOT (secreted host-responsive protein of Tetranychidae) family. The proteins were divided in three groups based on sequence similarity. Unlike TuSHOT3 genes, TuSHOT1 and TuSHOT2 genes were highly expressed when feeding on a subset of family Fabaceae, while expression was depleted on other hosts. TuSHOT1 and TuSHOT2 expression was induced within 24 h after certain host transfers, pointing toward transcriptional plasticity rather than selection as the cause. Transfer from an 'inducer' to a 'noninducer' plant was associated with slow yet strong downregulation of TuSHOT1 and TuSHOT2, occurring over generations rather than hours. This asymmetric on and off regulation points toward host-specific effects of SHOT proteins, which is further supported by the diversity of SHOT genes identified in Tetranychidae with a distinct host repertoire.

Prey preference of the phytoseiid mite Typhlodromus pyri. 1. Response to volatile kairomones.

NARCIS (Netherlands)

Dicke, M.

1988-01-01

Using a Y-tube olfactometer, a study has been made of the response of females of the predatory miteTyphlodromus pyri Scheuten (Acarina: Phytoseiidae) to volatile kairomones of three prey species: the European red spider mite (Panonychus ulmi (Koch)), the two-spotted spider mite (Tetranychus urticae

Evaluation of selected acaricides against two-spotted spider mite (Acari: Tetranychidae) on greenhouse cotton using multispectral data

Science.gov (United States)

Two-spotted spider mite (TSSM), Tetranychus urticae (Koch), is an early season pest of cotton in the mid-southern United States and causes reduction in yield, fiber quality and impaired seed germination. Objectives of this study were to investigate the efficacy of abamectin and spiromesifen with two...

Voluntary Falling in Spider Mites in Response to Different Ecological Conditions at Landing Points

OpenAIRE

Ohzora, Yousuke; Yano, Shuichi

2011-01-01

We examined voluntary-falling behaviour by adult females of the two-spotted spider mite Tetranychus urticae Koch (Acari: Tetranychidae) and one of its major predators Neoseiulus californicus McGregor (Acari: Phytoseiidae). Experiments were conducted using a setup in which mites could only move onto one of two landing points by falling. Significantly more T. urticae females fell onto available food leaves compared to non-food or heavily infested leaves, whereas significantly fewer females fell...

Metabolite profiling reveals a specific response in tomato to predaceous Chrysoperla carnea larvae and herbivore(s-predator interactions with the generalist pests Tetranychus urticae and Myzus persicae

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Audrey Errard

2016-08-01

Full Text Available The spider mite Tetranychus urticae Koch and the aphid Myzus persicae (Sulzer both infest a number of economically significant crops, including tomato (Solanum lycopersicum. Although used for decades to control pests, the impact of green lacewing larvae Chrysoperla carnea (Stephens on plant biochemistry was not investigated. Here we used profiling methods and targeted analyses to explore the impact of the predator and herbivore(s-predator interactions on tomato biochemistry. Each pest and pest-predator combination induced a characteristic metabolite signature in the leaf and the fruit thus, the plant exhibited a systemic response. The treatments had a stronger impact on non-volatile metabolites including abscisic acid and amino acids in the leaves in comparison with the fruits. In contrast, the various biotic factors had a greater impact on the carotenoids in the fruits. We identified volatiles such as myrcene and α-terpinene which were induced by pest-predator interactions but not by single species, and we demonstrated the involvement of the phytohormone abscisic acid in tritrophic interactions for the first time. More importantly, C. carnea larvae alone impacted the plant metabolome, but the predator did not appear to elicit particular defense pathways on its own. Since the presence of both C. carnea larvae and pest individuals elicited volatiles which were shown to contribute to plant defense, C. carnea larvae could therefore contribute to the reduction of pest infestation, not only by its preying activity, but also by priming responses to generalist herbivores such as T. urticae and M. persicae. On the other hand, the use of C. carnea larvae alone did not impact carotenoids thus, was not prejudicial to the fruit quality. The present piece of research highlights the specific impact of predator and tritrophic interactions with green lacewing larvae, spider mites and aphids on different components of the tomato primary and secondary metabolism

Compatibility of the entomopathogenic fungus Beauveria bassiana with flufenoxuron and azadirachtin against Tetranychus urticae.

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Hernández, M M; Martínez-Villar, E; Peace, C; Pérez-Moreno, I; Marco, V

2012-12-01

Laboratory studies were developed to evaluate the compatibility of flufenoxuron and azadirachtin with Beauveria bassiana against Tetranychus urticae larvae along with the required Probit analysis of the involved chemicals on all of the life stages of this mite. Flufenoxuron displayed parallel regression lines for the mortality of eggs, deutonymphs and adults. Larvae and protonymphs were the most susceptible life stages. Protonymphs were 35 times more sensitive than eggs and adults. Azadirachtin gave equal mortality on proto- and deutonymphs. The response of eggs and adults was equivalent when treated with azadirachtin. The regression lines for proto- and deutonymphs were parallel to those of adults and eggs yet three times more sensitive. The effects of separate combinations of the entomopathogenic fungus Beauveria bassiana at its LC(20) with flufenoxuron and azadirachtin at their corresponding LC(40) were evaluated on mite larvae. The application of flufenoxuron with B. bassiana revealed a clear synergy. While the combination of azadirachtin and B. bassiana had an additive effect. These combinations with B. bassiana could improve mite control by contributing to a decline in the likelihood of resistance so often described in the literature.

Active optical sensor assessment of spider mite damage on greenhouse beans and cotton

Science.gov (United States)

The two-spotted spider mite, Tetranychus urticae Koch is an important pest of cotton in mid-southern United States and causes yield reduction, and deprivation in fiber fitness. A greenhouse colony of the spider mite was used to infest cotton and pinto beans at the three-leaf and trifoliate stages, r...

Chlorophyll and its degradation products in the two-spotted spider mite, Tetranychus urticae: observations using epifluorescence and confocal laser scanning microscopy.

Science.gov (United States)

Occhipinti, Andrea; Maffei, Massimo E

2013-10-01

Chlorophyll and chlorophyll degradation products were observed in the two-spotted spider mite (Tetranychus urticae) using epifluorescence microscopy (EFM) and confocal laser scanning microscopy (CLSM). A clear red fluorescence (EFM) and a fluorescence induced by a laser wavelength of 650 nm (CLSM) were observed. In the lateral caeca, in the ventriculus and in the excretory organ, a bright light blue fluorescence was observed in close association with chlorophyll by using EFM. The same material can be localized with CLSM by using a laser with a wavelength of 488 nm. By comparison with synthetic guanine, this bright fluorescence is supposed to be guanine. The presence of guanine fluorescence in the mite pellets confirms this hypothesis. A possible mechanism for guanine formation is discussed.

The residual and direct effects of reduced-risk and conventional miticides on twospotted spider mites, Tetranychus urticae (Acari: Tetranychidae) and predatory mites (Acari: Phytoseiidae)

International Nuclear Information System (INIS)

Liburd, O.E.; White, J.C.; Rhodes, E.M.; Browdy, A.A.

2007-01-01

The residual effects of several reduced-risk and conventional miticides were evaluated in strawberries (Fragaria × ananassa Duchesne) on the twospotted spider mite (TSSM), Tetranychus urticae Koch (Acari: Tetranychidae) and on 2 predatory mites, Neoseiulus californicus McGregor and Phytoseiulus persimilis Athias-Henriot (Acari: Phytoseiidae). Experiments were conducted in the laboratory and greenhouse. The greenhouse experiments also tested the direct effects of the miticides on TSSM. The efficacy of conventional and reduced-risk miticides was evaluated on strawberry leaf discs and on whole plants for control of TSSM. Furthermore, the residual effects of these miticides were evaluated on whole strawberry plants against selective predatory mites. For TSSM, 5 treatments were evaluated: a conventional miticide; fenbutatin-oxide (Vendex[reg]) and 3 reduced-risk miticides; binfenazate (Acramite 50WP[reg]), activated garlic extract (Repel[reg]), sesame seed and castor oil (Wipeout[reg]), and a water-treated control. For predatory mites, the residual effects of only Acramite[reg] and Vendex[reg] were evaluated. Acramite[reg] was the most effective acaricide in reducing TSSM populations in both the laboratory and greenhouse experiments. Vendex[reg] and Wipeout[reg] were also effective in the laboratory, but did not cause significant reduction of TSSM in the greenhouse. Repel[reg] was the least effective of the 4 pesticides evaluated. Neither Acramite[reg] nor Vendex[reg] had a significant effect on either predatory mite species. However, there appeared to be more predatory mites on the Vendex[reg]-treated plants than on the Acramite[reg]-treated plants. There were significantly more predatory mites of both species on the cue plants, which were inoculated with TSSM versus the non-cue plants, which were not inoculated. (author) [es

Efficacy of Nanoencapsulated Thymus eriocalyx and Thymus kotschyanus Essential Oils by a Mesoporous Material MCM-41 Against Tetranychus urticae (Acari: Tetranychidae).

Science.gov (United States)

Ebadollahi, Asgar; Sendi, Jalal Jalali; Aliakbar, Alireza

2017-12-05

Inspite of well-established potentiality of plant essential oils as biopesticides, their environmentally low persistence is considered as a hindering obstacle for its commercialization. In the present study, chemical composition and toxicity of essential oils isolated from leaves of Thymus eriocalyx and Thymus kotschyanus were evaluated against two-spotted spider mite, Tetranychus urticae. The chemicals present in the crude oil were found to be thymol (28.83%), oleic acid (11.51%), palmitic acid (8.60%), borneol (5.72%), ρ-cymene (3.60%), and 1,8-cineole (3.57%) in the essential oil of T. eriocalyx, and camphene (35.59%), linalyl acetate (20.47%), linalool (14.75%), α-terpineol (13.87%), and geranyl acetate (3.07%) in the essential oil of T. kotschyanus. The essential oils had strong fumigant toxicity on the adult females of Te. urticae and their fumigation persistence was prolonged until 6 and 5 d, respectively, for T. eriocalyx and T. kotschyanus. Loading of essential oils in MCM-41 increased their stability and persistence was extended up to 20 and 18 d for T. eriocalyx and T. kotschyanus. Further, mite mortality increased from 80 to 203 mites by T. eriocalyx and from 58 to 186 mites by T. kotschyanus nanoencapsulated essential oils. Based on these results, nanoencapsulation of T. eriocalyx and T. kotschyanus essential oils in MCM-41 may be a useful method for their application in the management of Te. urticae. © The Author(s) 2017. Published by Oxford University Press on behalf of Entomological Society of America. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.

Development of food preservation and processing techniques by radiation - Quarantine treatment of agricultural products for export and import by gamma irradiation

Energy Technology Data Exchange (ETDEWEB)

Kwon, Joong Ho; Kang, H. J.; Chung, H. W.; Roh, M. J. [Kyungbuk National University, Taegu (Korea)

2000-04-01

To pre-establish an alternative technique to the toxic fumigant, methyl bromide which is the current quarantine measure of agricultural products for export, some selected agricultural products, such as apple and pear, were subjected to a preliminary study to confirm the comparative effects of gamma irradiation and MeBr fumigant on their disinfestation and quality, thereby preparing the basic data for the practical approach. Current quarantine activities were examined and the related limitations were investigated. Quarantine-related pests were investigated on their radiosensitivity and disinfestation effects by both treatments. The pests in apple and pear, Tetranychus urticae Koch, Panonychus ulmis Koch revealed a 100% mortality at around 17 days after irradiation of 3 kGy but it was too high dose for apple and pear. Tetranychus urticae Koch, Panonychus ulmi Koch from both apple and pear showed an increased mortality when exposed to 1 {approx} 2 kGy irradiation, resulting in apparent mortality 1 month later. 1 {approx} 2 kGy irradiation could be recommended for apple and pear. Current fumigation was perfect in its disinfesting capability, but it caused the detrimental effects on physical quality of agricultural produce. Whereas, irradiation doses suitable for controlling the pests did not induce any significant changes in the quality of the samples. 40 refs., 64 figs., 160 tabs. (Author)

Influence de l'usage préventif des pesticides sur les acariens Tetranychus urticae et Phytoseiulus persimilis (Acari : Tetranychidae, Phytoseiidae présents en cultures de fraisiers du Nord du Maroc

Directory of Open Access Journals (Sweden)

Lagziri, M.

2015-01-01

Full Text Available Influence of previous pesticide use on Tetranychus urticae and Phytoseiulus persimilis (Acari: Tetranychidae, Phytoseiidae from strawberry crops in the north of Morocco. Description of the subject. Effects of recommended doses of five common pesticides in the strawberries of Loukkos area (Morocco were tested on the two-spotted spider mite Tetranychus urticae and its predatory mite Phytoseiulus persimilis. Laboratory study assessed the contact toxicity of one avermectin miticide (abamectin, two pyrethrinoid insecticide-acaricides (bifenthrin and lambda-cyalothrin, and two fungicides: firstly, mancozeb, which belongs to the dithiocarbamates family of chemicals and secondly, hexaconazole, of the triazole family. Objectives. The aim of the present study was to test in laboratory conditions the effect of five pesticides on the two-spotted spider mite, T. urticae and its predatory mite, P. persimilis. The five pesticides tested were those most frequently applied for at least two years on strawberries at the experimental site. Method. Bioassays were performed with populations of mites originating from different plots with various crop protection backgrounds. The first group of plots had been repeatedly treated with the five tested pesticides during a two-year period, the second group had been moderately treated, and the third had been treated once with the tested pesticides. Results. Our results showed that the tested pesticides provided effective control of T. urticae but that they were not compatible with use on the predatory mite P. persimilis, as these particular mites did not usually come into contact with these products. On the other hand, in plots where pesticides had been used for a long time, the susceptibility of P. persimilis populations to these products was significantly reduced. Conclusions. If the tested pesticides are to be considered for integrated pest control programs in plots where they have been used for a long time and where P

DNA-content in isolated nuclei of postembryonic stages of progeny from normal and irradiated males of Tetranychus urticae (Acari Tetranychidoe)

International Nuclear Information System (INIS)

Tempelaar, M.J.

1980-01-01

The lC DNA-content of isolated nuclei of postembryonic stages of Tetranychus urticae stained with the classic and a modified Schiff's reagent was cytophotometrically estimated as 0.1 pg, a low value in animals. For many tissues of this arrhenotokus species the ploidy ratio between males and females is 1:2, indicating the absence of sex-related differences in ploidy. In addition, DNA measurements were performed to evaluate irradiation-experiments, starting with X-irradiation of mature sperm in males with doses known from previous work to induce chromosomal fragments that are subject to loss and missegregation in the embryonic mitotic stages of the female progeny despite the presumed holokinetic nature of the chromosomes. The DNA-content of the nuclei of the surviving postembryonic preadult stages did not indicate the occurrence of nuclei with in-between male/female values, ruling out loss and missegregation of fragments as important factors in postembryonic lethality. Abnormally low DNA-values in some adult females could be attributed to development of embryos before oviposition caused by radiation-induced effects. (orig.) [de

Alternating temperatures affect life table parameters of Phytoseiulus persimilis, Neoseiulus californicus (Acari: Phytoseiidae) and their prey Tetranychus urticae (Acari: Tetranychidae).

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Vangansbeke, Dominiek; De Schrijver, Lien; Spranghers, Thomas; Audenaert, Joachim; Verhoeven, Ruth; Nguyen, Duc Tung; Gobin, Bruno; Tirry, Luc; De Clercq, Patrick

2013-11-01

Increasing energy costs force glasshouse growers to switch to energy saving strategies. In the temperature integration approach, considerable daily temperature variations are allowed, which not only have an important influence on plant growth but also on the development rate of arthropods in the crop. Therefore, we examined the influence of two constant temperature regimes (15 °C/15 °C and 20 °C/20 °C) and one alternating temperature regime (20 °C/5 °C, with an average of 15 °C) on life table parameters of Phytoseiulus persimilis and Neoseiulus californicus and their target pest, the two-spotted spider mite Tetranychus urticae at a 16:8 (L:D) h photoperiod and 65 ± 5 % RH. For females of both predatory mites the alternating temperature regime resulted in a 25-30 % shorter developmental time as compared to the corresponding mean constant temperature regime of 15 °C/15 °C. The immature development of female spider mites was prolonged for 7 days at 15 °C/15 °C as compared to 20 °C/5 °C. With a daytime temperature of 20 °C, no differences in lifetime fecundity were observed between a nighttime temperature of 20 and 5 °C for P. persimilis and T. urticae. The two latter species did show a higher lifetime fecundity at 20 °C/5 °C than at 15 °C/15 °C, and their daily fecundity at the alternating regime was about 30 % higher than at the corresponding mean constant temperature. P. persimilis and T. urticae showed no differences in sex ratio between the three temperature regimes, whereas the proportion of N. californicus females at 15 °C/15 °C (54.2 %) was significantly lower than that at 20 °C/5 °C (69.4 %) and 20 °C/20 °C (67.2 %). Intrinsic rates of increase were higher at the alternating temperature than at the corresponding mean constant temperature for both pest and predators. Our results indicate that thermal responses of the studied phytoseiid predators to alternating temperature regimes used in energy saving strategies in glasshouse crops may

The responses of cucumber plants subjected to different salinity or fertilizer concentrations and reproductive success of Tetranychus urticae mites on these plants.

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Khodayari, Samira; Abedini, Fatemeh; Renault, David

2018-05-01

The plant stress hypothesis posits that a herbivore's reproductive success increases when it feeds on stressed plants, while the plant vigor hypothesis predicts that a herbivore preferentially feeds on more vigorous plants. We examined these opposing hypotheses by growing spider mites (Tetranychus urticae) on the leaves of stressed and healthy (vigorous) cucumber plants. Host plants were grown under controlled conditions at low, moderate, and high concentrations of NaCl (to induce salinity stress), at low, moderate, and high fertilizer concentrations (to support growth), and without these additions (control). The effects of these treatments were evaluated by measuring fresh and dry plant biomass, carotenoid and chlorophyll content, antioxidant enzyme activity, and concentrations of PO 4 3- , K + , and Na + in plant tissues. The addition of low concentrations of fertilizer increased dry mass, protein, and carotenoid content relative to controls, suggesting a beneficial effect on plants. The highest NaCl treatment (2560 mg L -1 ) resulted in increased Na + and protein content relative to control plants, as well as reduced PO 4 3- , K + , and chlorophyll levels and reduced catalase and ascorbate peroxidase enzyme activity levels. Analysis of life table data of T. urticae mites raised on leaves from the aforementioned plant groups showed the intrinsic rate of increase (r) for mites was 0.167 day -1 in control specimens, 0.125 day -1 for mites reared on plants treated with a moderate concentration of fertilizer (10 mL L -1 ), and was highest (0.241 day -1 ) on plants grown under moderate salinity conditions (1920 mg L -1 NaCl). Reproductive success of T. urticae did not differ on plants watered with a moderate concentration of NaCl or a high concentration of fertilizer. The moderately-stressed plants formed a favorable environment for the development and reproduction of spider mites, supporting the plant stress hypothesis.

New developments in insecticide resistance in the glasshouse whitefly (Trialeurodes vaporariorum) and the two-spotted spider mite (Tetranychus urticae) in the UK.

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Gorman, Kevin; Hewitt, Fiona; Denholm, Ian; Devine, Gregor J

2002-02-01

A recent survey of insecticide resistance in two of the most problematic pests in UK glasshouses revealed some new developments. At least some individuals in all UK samples of Trialeurodes vaporariorum that were tested resisted the insect growth regulator (IGR) buprofezin. The most strongly resistant strains were unaffected by the field application rate of this compound, and even samples from populations that had never been exposed to buprofezin contained individuals that survived the highest concentration applied (10,000 mg litre-1). The field rate of buprofezin was shown to select for resistance through vapour action alone. The benzophenylurea teflubenzuron, an unrelated IGR, was cross-resisted by buprofezin-resistant individuals. There was no evidence of resistance to imidacloprid, but all T vaporariorum strains tested, regardless of origin, exhibited a high innate tolerance to nicotine, when compared with another whitefly species, Bemisia tabaci. Marked resistance to fenbutatin oxide and tebufenpyrad was found in single glasshouse populations of Tetranychus urticae, but these compounds and abamectin appeared to remain highly effective against all other strains collected.

Toxicity of bifenazate and its principal active metabolite, diazene, to Tetranychus urticae and Panonychus citri and their relative toxicity to the predaceous mites, Phytoseiulus persimilis and Neoseiulus californicus.

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Ochiai, Noriaki; Mizuno, Masayuki; Mimori, Norihiko; Miyake, Toshihiko; Dekeyser, Mark; Canlas, Liza Jara; Takeda, Makio

2007-01-01

Bifenazate is a novel carbazate acaricide discovered by Uniroyal Chemical (now Chemtura Corporation) for the control of phytophagous mites infesting agricultural and ornamental crops. Its acaricidal activity and that of its principal active metabolite, diazene, were characterized. Bifenazate and diazene had high toxicity and specificity both orally and topically to all life stages of Tetranychus urticae and Panonychus citri. Acute poisoning was observed with no temperature dependency. No cross-resistance was found to mites resistant to several other classes of acaricides, such as tebufenpyrad, etoxazole, fenbutatin oxide and dicofol. Bifenazate remained effective for a long time with only about a 10% loss of efficacy on T. urticae after 1 month of application in the field. All stages of development of the predatory mites, Phytoseiulus persimilis and Neoseiulus californicus, survived treatment by both bifenazate and diazene. When adult females of the two predatory mite species were treated with either bifenazate or diazene, they showed a normal level of fecundity and predatory activity in the laboratory, effectively suppressing spider mite population growth. Even when the predators were fed spider mite eggs that had been treated previously with bifenazate, they survived. These findings indicate that bifenazate is a very useful acaricide giving high efficacy, long-lasting activity and excellent selectivity for spider mites. It is, therefore, concluded that bifenazate is an ideal compound for controlling these pest mites.

Controle biológico do ácaro rajado com ácaros predadores fitoseídeos (Acari: Tetranychidae, Phytoseiidae em culturas de pepino e morango Biological control of the two-spotted spider mite (Acari: Tetranychidae, Phytoseiidae in cucumber and strawberry crops

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M.A. Watanabe

1994-04-01

Full Text Available O ácaro rajado, Tetranychus urticae Koch, é considerado uma das principais pragas de hortaliças e várias outras culturas no Brasil, em áreas onde um considerável volume de acaricidas é anualmente empregado no seu controle. O objetivo deste trabalho foi testar a viabilidade técnica do emprego dos fitoseídeos Amblyseius idaeus (Denmark & Muma e Phytoseudus macropilis (Banks, comum ente encontrados no Brasil, no controle de T. urticae em pepino e morangueiro em Jaguaríúna,SP. Utilizou-se o delineamento experimental em blocos casualizados, com 4 repetições e 4 tratamentos (T1-T4 para o pepino e 5 tratamentos para o morangueiro (T1-T5: T1, testemunha; T2, pulverizações semanais de Malation para a exclusão de predadores nativos; T3, liberações periódicas de A.idaeus; T4, liberações periódicas de P.macropilis; T5, pulverizações semanais de avermectina para a exclusão de ácaros fitófagos e predadores nativos. Apenas A.idaeus se estabeleceu na cultura de pepino, reduzindo significativamente a população de T. urticae. Ambas espécies de predadores se estabeleceram na cultura do morango e reduziram significativamente a população de T.urticae.The two-spotted spider mite, Tetranychus urticae Koch, is considered one of the main pests of horticultural and other crops in Brazil, in areas where a considerable volume of acaricides is annually used for its control. The objective of this work was to test the technical viability of using phytoseiids Amblyseius idaeus (Denmark & Muma and Phytoseudus macropilis (Banks, commonly found in Brazil, to control T .urticae in cucumber and strawberry crops in Jaguaríúna,SP. A randomized complete block design was used, with 4 replicates and 4 treatments for cucumber (T1-T4 and 5 treatments for strawberry crops (T1-T5: T1, control; T2, weekly sprays of malathion for exclusion of native predators; T3, periodical releases of A.idaeus; T4, periodical releases of P. macropilis; T5, weekly sprays of

Analysis of insecticide resistance-related genes of the Carmine spider mite Tetranychus cinnabarinus based on a de novo assembled transcriptome.

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Zhifeng Xu

Full Text Available The carmine spider mite (CSM, Tetranychus cinnabarinus, is an important pest mite in agriculture, because it can develop insecticide resistance easily. To gain valuable gene information and molecular basis for the future insecticide resistance study of CSM, the first transcriptome analysis of CSM was conducted. A total of 45,016 contigs and 25,519 unigenes were generated from the de novo transcriptome assembly, and 15,167 unigenes were annotated via BLAST querying against current databases, including nr, SwissProt, the Clusters of Orthologous Groups (COGs, Kyoto Encyclopedia of Genes and Genomes (KEGG and Gene Ontology (GO. Aligning the transcript to Tetranychus urticae genome, the 19255 (75.45% of the transcripts had significant (e-value <10-5 matches to T. urticae DNA genome, 19111 sequences matched to T. urticae proteome with an average protein length coverage of 42.55%. Core Eukaryotic Genes Mapping Approach (CEGMA analysis identified 435 core eukaryotic genes (CEGs in the CSM dataset corresponding to 95% coverage. Ten gene categories that relate to insecticide resistance in arthropod were generated from CSM transcriptome, including 53 P450-, 22 GSTs-, 23 CarEs-, 1 AChE-, 7 GluCls-, 9 nAChRs-, 8 GABA receptor-, 1 sodium channel-, 6 ATPase- and 12 Cyt b genes. We developed significant molecular resources for T. cinnabarinus putatively involved in insecticide resistance. The transcriptome assembly analysis will significantly facilitate our study on the mechanism of adapting environmental stress (including insecticide in CSM at the molecular level, and will be very important for developing new control strategies against this pest mite.

Active optical sensor assessment of spider mite damage on greenhouse beans and cotton.

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Martin, Daniel E; Latheef, Mohamed A

2018-02-01

The two-spotted spider mite, Tetranychus urticae Koch, is an important pest of cotton in mid-southern USA and causes yield reduction and deprivation in fiber fitness. Cotton and pinto beans grown in the greenhouse were infested with spider mites at the three-leaf and trifoliate stages, respectively. Spider mite damage on cotton and bean canopies expressed as normalized difference vegetation index indicative of changes in plant health was measured for 27 consecutive days. Plant health decreased incrementally for cotton until day 21 when complete destruction occurred. Thereafter, regrowth reversed decline in plant health. On spider mite treated beans, plant vigor plateaued until day 11 when plant health declined incrementally. Results indicate that pinto beans were better suited as a host plant than cotton for rearing T. urticae in the laboratory.

Comparison of thermal activity thresholds of the spider mite predators Phytoseiulus macropilis and Phytoseiulus persimilis (Acari: Phytoseiidae).

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Coombs, Megan R; Bale, Jeffrey S

2013-04-01

The lower and upper thermal activity thresholds of the predatory mite Phytoseiulus macropilis Banks (Acari: Phytoseiidae) were compared with those of its prey Tetranychus urticae Koch (Acari: Tetranychidae) and one of the alternative commercially available control agents for T. urticae, Phytoseiulus persimilis Athias-Henriot. Adult female P. macropilis retained ambulatory function (CTmin) and movement of appendages (chill coma) at significantly lower temperatures (8.2 and 0.4 °C, respectively) than that of P. persimilis (11.1 and 3.3 °C) and T. urticae (10.6 and 10.3 °C). As the temperature was raised, P. macropilis ceased walking (CTmax) and entered heat coma (42.7 and 43.6 °C), beyond the upper locomotory limits of P. persimilis (40.0 and 41.1 °C), but before T. urticae (47.3 and 48.7 °C). Walking speeds were investigated and P. persimilis was found to have significantly faster ambulation than P. macropilis and T. urticae across a range of temperatures. The lower thermal activity threshold data indicate that P. macropilis will make an effective biological control agent in temperate climates.

The effects of prey patchiness, predator aggregation, and mutual interference on the functional response of Phytoseiulus persimilis feeding on Tetranychus urticae (Acari: Phytoseiidae, Tetranychidae).

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Nachman, Gösta

2006-01-01

The spatial distributions of two-spotted spider mites Tetranychus urticae and their natural enemy, the phytoseiid predator Phytoseiulus persimilis, were studied on six full-grown cucumber plants. Both mite species were very patchily distributed and P. persimilis tended to aggregate on leaves with abundant prey. The effects of non-homogenous distributions and degree of spatial overlap between prey and predators on the per capita predation rate were studied by means of a stage-specific predation model that averages the predation rates over all the local populations inhabiting the individual leaves. The empirical predation rates were compared with predictions assuming random predator search and/or an even distribution of prey. The analysis clearly shows that the ability of the predators to search non-randomly increases their predation rate. On the other hand, the prey may gain if it adopts a more even distribution when its density is low and a more patchy distribution when density increases. Mutual interference between searching predators reduces the predation rate, but the effect is negligible. The stage-specific functional response model was compared with two simpler models without explicit stage structure. Both unstructured models yielded predictions that were quite similar to those of the stage-structured model.

Deciphering the Metabolic Changes Associated with Diapause Syndrome and Cold Acclimation in the Two-Spotted Spider Mite Tetranychus urticae

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Khodayari, Samira; Moharramipour, Saeid; Larvor, Vanessa; Hidalgo, Kévin; Renault, David

2013-01-01

Diapause is a common feature in several arthropod species that are subject to unfavorable growing seasons. The range of environmental cues that trigger the onset and termination of diapause, in addition to associated hormonal, biochemical, and molecular changes, have been studied extensively in recent years; however, such information is only available for a few insect species. Diapause and cold hardening usually occur together in overwintering arthropods, and can be characterized by recording changes to the wealth of molecules present in the tissue, hemolymph, or whole body of organisms. Recent technological advances, such as high throughput screening and quantification of metabolites via chromatographic analyses, are able to identify such molecules. In the present work, we examined the survival ability of diapausing and non-diapausing females of the two-spotted spider mite, Tetranychus urticae, in the presence (0 or 5°C) or absence of cold acclimation. Furthermore, we examined the metabolic fingerprints of these specimens via gas chromatography-mass spectrophotometry (GC-MS). Partial Least Square Discriminant Analysis (PLS-DA) of metabolites revealed that major metabolic variations were related to diapause, indicating in a clear cut-off between diapausing and non-diapausing females, regardless of acclimation state. Signs of metabolic depression were evident in diapausing females, with most amino acids and TCA cycle intermediates being significantly reduced. Out of the 40 accurately quantified metabolites, seven metabolites remained elevated or were accumulated in diapausing mites, i.e. cadaverine, gluconolactone, glucose, inositol, maltose, mannitol and sorbitol. The capacity to accumulate winter polyols during cold-acclimation was restricted to diapausing females. We conclude that the induction of increased cold hardiness in this species is associated with the diapause syndrome, rather than being a direct effect of low temperature. Our results provide novel

Suspension of Egg Hatching Caused by High Humidity and Submergence in Spider Mites.

Science.gov (United States)

Ubara, Masashi; Osakabe, Masahiro

2015-08-01

We tested the effects of high humidity and submergence on egg hatching of spider mites. In both the high humidity and submergence treatments, many Tetranychus and Panonychus eggs did not hatch until after the hatching peak of the lower humidity or unsubmerged controls. However, after humidity decreased or water was drained, many eggs hatched within 1-3 h. This was observed regardless of when high humidity or submergence treatments were implemented: either immediately after oviposition or immediately before hatching was due. Normal eyespot formation was observed in most eggs in the high humidity and submergence treatments, which indicates that spider mite embryos develop even when eggs are underwater. Therefore, delays in hatching are not caused by delayed embryonic development. A delay in hatching was always observed in Panonychus citri (McGregor) but was more variable in Tetranychus urticae Koch and Tetranychus kanzawai Kishida. The high humidity and submergence treatments affected but did not suppress larval development in these species. In contrast, many Oligonychus eggs died following the high humidity treatments. In Tetranychus and Panonychus spider mites, suspension of egg hatching may mitigate the adverse effects of rainfall. © 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.

Functional response of predatory thrips to two-spotted spider mite - influence of pesticides

DEFF Research Database (Denmark)

Pakyari, Hajar; Enkegaard, Annie

2013-01-01

A leaf disc bioassay was used to investigate the effects of abamectin and fenpropathrin on the functional response of an acarophagous thrips, Scolothrips longicornis Priesner, to eggs of Tetranychus urticae Koch at 25 ± 1°C, 60 ± 10% RH, 16:8 h (L:D). The type of the functional response differed....... The theoretical maximum number of prey attacked by the thrips was 49.67 and 23.67 eggs per day for females and males, respectively; both maxima were attained in the control treatment. These values were reduced for males exposed to full doses of either pesticide and for females exposed to both half and full doses...

Differential effects of plant species on a mite pest (Tetranychus utricae) and its predator (Phytoseiulus persimilis): implications for biological control.

Science.gov (United States)

Skirvin, D J; de Courcy Williams, M

1999-06-01

The influence of plant species on the population dynamics of the spider mite pest, Tetranychus urticae, and its predator, Phytoseiulus persimilis, was examined as a prerequisite to effective biological control on ornamental nursery stock. Experiments have been done to investigate how the development, fecundity and movement of T. urticae, and the movement of P. persimilis were affected by plant species. A novel experimental method, which incorporates plant structure, was used to investigate the functional response of P. persimilis. Development times for T. urticae were consistent with published data and did not differ with plant species in a biologically meaningful way. Plant species was shown to have a major influence on fecundity (P < 0.001) and movement of the pest mite (P < 0.01), but no influence on the movement of the predator. The movement of both pest and predator was shown to be related to the density of the adult pest mites on the plant (P < 0.001). Plant structure affected the functional response, particularly in relation to the ability of the predator to locate prey at low densities. The impact of these findings on the effective use of biological control on ornamental nursery stock is discussed.

Can Euseius alatus DeLeon (Acari: Phytoseiidae) prey on Aceria guerreronis Keifer (Acari: Eriophyidae) in coconut palm?

International Nuclear Information System (INIS)

Melo, Jose W. da S.; Domingos, Cleiton A.; Gondim Junior, Manoel G.C.; Moraes, Gilberto J. de

2009-01-01

Mites of the genus Euseius are generally considered specialist as pollen feeders. Euseius alatus DeLeon is one of the six species of phytoseiid mites most commonly found on coconut plants in northeast Brazil associated with Aceria guerreronis Keifer. Although the morphology of E. alatus does not favor the exploitation of the meristematic area of the fruit inhabited by A. guerreronis, the predator may have some role in the control of this eriophyid during the dispersion process. The objective of this work was to evaluate the development and reproduction of E. alatus on the following diets: A. guerreronis, Ricinus communis pollen (Euphorbiaceae), and Tetranychus urticae Koch (Tetranychidae) + R. communis pollen + honey solution 10%. Euseius alatus developed slightly faster and had slightly higher oviposition rate when feeding on the diet composed of T. urticae + pollen + honey. However, life table parameters were very similar on all diets, suggesting that E. alatus may contribute in reducing the population of A. guerreronis in the field. (author)

Can Euseius alatus DeLeon (Acari: Phytoseiidae) prey on Aceria guerreronis Keifer (Acari: Eriophyidae) in coconut palm?; Pode Euseius alatus DeLeon (Acari: Phytoseiidae) predar Aceria guerreronis Keifer (Acari: Eriophyidae) em coqueiro?

Energy Technology Data Exchange (ETDEWEB)

Melo, Jose W. da S.; Domingos, Cleiton A.; Gondim Junior, Manoel G.C. [Universidade Federal Rural de Pernambuco (UFRPE), Recife, PE (Brazil). Dept. de Agronomia. Area de Fitossanidade]. E-mail: mguedes@depa.ufrpe.br; Moraes, Gilberto J. de [Universidade de Sao Paulo (USP), Piracicaba, SP (Brazil). Escola Superior de Agricultura Luiz de Queiroz (ESALQ). Dept. de Entomologia, Fitopatologia e Zoologia Agricola]. E-mail: gjmoraes@carpa.ciagri.usp.br

2009-01-15

Mites of the genus Euseius are generally considered specialist as pollen feeders. Euseius alatus DeLeon is one of the six species of phytoseiid mites most commonly found on coconut plants in northeast Brazil associated with Aceria guerreronis Keifer. Although the morphology of E. alatus does not favor the exploitation of the meristematic area of the fruit inhabited by A. guerreronis, the predator may have some role in the control of this eriophyid during the dispersion process. The objective of this work was to evaluate the development and reproduction of E. alatus on the following diets: A. guerreronis, Ricinus communis pollen (Euphorbiaceae), and Tetranychus urticae Koch (Tetranychidae) + R. communis pollen + honey solution 10%. Euseius alatus developed slightly faster and had slightly higher oviposition rate when feeding on the diet composed of T. urticae + pollen + honey. However, life table parameters were very similar on all diets, suggesting that E. alatus may contribute in reducing the population of A. guerreronis in the field. (author)

Spatial distribution of phytophagous mites (Aca ri: Tetranychidae) on strawberry plants

International Nuclear Information System (INIS)

Fadini, Marcos A.M.; Venzon, Madelaine; Oliveira, Hamilton G.; Pallini, Angelo; Vilela, Evaldo F.

2007-01-01

Many phytophagous mites can attack strawberry plants, Fragaria x ananassa, among them the southern red mite, Oligonychus ilicis McGregor, and the two-spotted spider mite, Tetranychus urticae Koch. They are found together feeding on the same plant on the upper and underside of the leaves, respectively. Here we studied the choice for feeding sites of O. ilicis and T. urticae on strawberry plants. The first hypothesis tested whether the feeding site choice would be related to the fitness of the species. The second hypothesis dealt whether the feeding site would be determined by the presence of a heterospecific mite. We evaluated the preference, biology and reproductive success of O. ilicis and T. urticae on the under and upper side surface of strawberry leaves infested or not by the heterospecific. O. ilicis preferred to stay on the upper side surface while T. urticae preferred the underside. The preference for the leaf surface correlated with the reproductive success of the species (measured by the intrinsic growth rate). The choice pattern of feeding sites did not alter when the choice test was applied using sites previously infested by heterospecific. Although O. ilicis and T. urticae, apparently, do not interact directly for feeding sites, there is a chance that the first species induces defenses in strawberry plant enabling to reduce the fitness of the second species. The possibility of those species stay together on strawberry plant increases the damage capacity to the culture. (author)

The influence of sublethal deposits of agricultural mineral oil on the functional and numerical responses of Phytoseiulus persimilis (Acari: Phytoseiidae) to its prey, Tetranychus urticae (Acari: Tetranychidae).

Science.gov (United States)

Xue, Yingen; Meats, Alan; Beattie, G Andrew C; Spooner-Hart, Robert; Herron, Grant A

2009-08-01

Occasional pesticide application in integrated pest management to at least part of a crop requires that any biological control agents must re-invade previously sprayed areas in order that resurgent pests can be constrained. The ability of the phytoseiid predatory mite Phytoseiulus persimilis to feed on adult two-spotted spider mite (TSSM) Tetranychus urticae on excised leaf discs in both control conditions and in a treatment with a sub lethal residue of agricultural mineral oil (AMO) was assessed. The predator exhibited a Type II functional response with the asymptote significantly higher in the AMO conditions due to the fact that the prey grew slower and reached a smaller size in this treatment. In terms of prey volume eaten, the satiation level of the predator was unchanged by the AMO deposits. The numbers of eggs produced by adult P. persimilis females at densities of 4, 8 and 16 TSSM adult females/disc in the control were significantly higher than those in the AMO treatment, but were similar for the higher density levels, 32 and 64 prey per disc. Thus the functional response in terms of volume of prey eaten explained the numerical response in terms of predator eggs produced. The presence of AMO deposits when the prey were at high density had no effect on predator efficiency (volume eaten) but resulted in a lower intake than that in control conditions when there was a greater distance between prey.

Genetic diversity within and among two-spotted spider mite resistant and susceptible common bean genotypes

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Zeinab YOUSEFI

2017-12-01

Full Text Available Two-spotted spider mite (Tetranychus urticae C. L. Koch, 1836, is one of the most destructive herbivores of common bean. Very little is known about the diversity among resistant sources in this crop. The present study was conducted to characterize 22 resistant and susceptible common bean genotypes by 8 Simple Sequence Repeats (SSRs and 8 Random Amplified Polymorphic DNA (RAPD markers. These SSR and RAPD primers produced 100 % and 81.8 % polymorphic bands. Based on RAPD fingerprints and SSR profiles, pairwise genetic similarity ranged from 0.0 to 0.857 and from 0.125 to 1, respectively. The resistant and susceptible common bean accessions were grouped together in the dendrograms generated from RAPD and SSR clustering analyses. The results indicate that RAPD and SSR analysis could be successfully used for the estimation of genetic diversity among genotypes. SSR markers could group genotypes according to their resistibility and susceptibility to the spotted spider mite but RAPD could not. Therefore, the SSR markers can facilitate the development of resistant common bean cultivars through breeding programs against T. urticae.

Effects of electron beam irradiation on cut flowers and mites

International Nuclear Information System (INIS)

Dohino, Toshiyuki; Tanabe, Kazuo

1994-01-01

Two spotted spider mite, Tetranychus urticae KOCH were irradiated with electron beams (2.5MeV) to develop an alternative quarantine treatment for imported cut flowers. The tolerance of eggs increased with age (1-5-day-old). Immature stages (larva-teleiochrysalis) irradiated at 0.4-0.8kGy increased tolerance with their development. Mated mature females irradiated at 0.4kGy or higher did not produce viable eggs, although temporary recovery was observed at 0.2kGy. Adult males were sterilized at 0.4kGy because non-irradiated virgin females mated with yielded female progeny malformed and sterilized. Various effects of electron beam irradiation were observed when nine species of cut flowers were irradiated in 5MeV Dynamitron accelerator. Chrysanthemum and rose were most sensitive among cut flowers. (author)

Analysis of insecticide resistance-related genes of the Carmine spider mite Tetranychus cinnabarinus based on a de novo assembled transcriptome.

Science.gov (United States)

Xu, Zhifeng; Zhu, Wenyi; Liu, Yanchao; Liu, Xing; Chen, Qiushuang; Peng, Miao; Wang, Xiangzun; Shen, Guangmao; He, Lin

2014-01-01

The carmine spider mite (CSM), Tetranychus cinnabarinus, is an important pest mite in agriculture, because it can develop insecticide resistance easily. To gain valuable gene information and molecular basis for the future insecticide resistance study of CSM, the first transcriptome analysis of CSM was conducted. A total of 45,016 contigs and 25,519 unigenes were generated from the de novo transcriptome assembly, and 15,167 unigenes were annotated via BLAST querying against current databases, including nr, SwissProt, the Clusters of Orthologous Groups (COGs), Kyoto Encyclopedia of Genes and Genomes (KEGG) and Gene Ontology (GO). Aligning the transcript to Tetranychus urticae genome, the 19255 (75.45%) of the transcripts had significant (e-value insecticide resistance in arthropod were generated from CSM transcriptome, including 53 P450-, 22 GSTs-, 23 CarEs-, 1 AChE-, 7 GluCls-, 9 nAChRs-, 8 GABA receptor-, 1 sodium channel-, 6 ATPase- and 12 Cyt b genes. We developed significant molecular resources for T. cinnabarinus putatively involved in insecticide resistance. The transcriptome assembly analysis will significantly facilitate our study on the mechanism of adapting environmental stress (including insecticide) in CSM at the molecular level, and will be very important for developing new control strategies against this pest mite.

How predictable are the behavioral responses of insects to herbivore induced changes in plants? Responses of two congeneric thrips to induced cotton plants.

Directory of Open Access Journals (Sweden)

Rehan Silva

Full Text Available Changes in plants following insect attack are referred to as induced responses. These responses are widely viewed as a form of defence against further insect attack. In the current study we explore whether it is possible to make generalizations about induced plant responses given the unpredictability and variability observed in insect-plant interactions. Experiments were conducted to test for consistency in the responses of two congeneric thrips, Frankliniella schultzei Trybom and Frankliniella occidentalis Pergrande (Thysanoptera: Thripidae to cotton seedlings (Gossypium hirsutum Linneaus (Malvales: Malvaceae damaged by various insect herbivores. In dual-choice experiments that compared intact and damaged cotton seedlings, F. schultzei was attracted to seedlings damaged by Helicoverpa armigera (Hübner (Lepidoptera: Noctuidae, Tetranychus urticae (Koch (Trombidiforms: Tetranychidae, Tenebrio molitor Linnaeus (Coleoptera: Tenebrionidae, F. schultzei and F. occidentalis but not to mechanically damaged seedlings. In similar tests, F. occidentalis was attracted to undamaged cotton seedlings when simultaneously exposed to seedlings damaged by H. armigera, T. molitor or F. occidentalis. However, when exposed to F. schultzei or T. urticae damaged plants, F. occidentalis was more attracted towards damaged plants. A quantitative relationship was also apparent, F. schultzei showed increased attraction to damaged seedlings as the density of T. urticae or F. schultzei increased. In contrast, although F. occidentalis demonstrated increased attraction to plants damaged by higher densities of T. urticae, there was a negative relationship between attraction and the density of damaging conspecifics. Both species showed greater attraction to T. urticae damaged seedlings than to seedlings damaged by conspecifics. Results demonstrate that the responses of both species of thrips were context dependent, making generalizations difficult to formulate.

Les déséquilibres biologiques provoqués par les traitements pesticides de la plante

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F. CHABOUSSOU

2016-10-01

Full Text Available L'influence qu'exercent les pesticides sur la physiologie et la biochimie des végétaux peut se répercuter sur les déprédateurs vivant aux dépens de ceux-ci. La présente étude est consacrée aux effets opérés dans ce sens par le DDT, le parathion et le carbaryl à l'égard de l'araignée rouge (Panonychus ulmi Koch, d'Eotetranychus carpini f. vitis Dosse et de Tetranychus urticae Koch sur vigne. Les trois insecticides favorisent le développement de ces acariens à la suite de modifications biochimiques de la plante qui sont analysées. Les fongicides zinèbe, manèbe et propinèbe exercent également une action sur le végétal qui devient alors plus sensible aux attaques de l'oïdium de la vigne. L'auteur souligne toute l'importance qu'il y a à tenir compte de ces phénomènes lors de la mise en œuvre de programmes de lutte intégrée.

Hal Koch

DEFF Research Database (Denmark)

Møller, Jes Fabricius

2007-01-01

Skal man forstå Hal Koch må han sættes ind i sin kontekst, politisk, teologisk og kulturelt. Han var præget af det 19. århundredes borgerlige dannelseskultur, socialkonservatismen og den lutherske statstanke.......Skal man forstå Hal Koch må han sættes ind i sin kontekst, politisk, teologisk og kulturelt. Han var præget af det 19. århundredes borgerlige dannelseskultur, socialkonservatismen og den lutherske statstanke....

Life history of Neoseiulus californicus (McGregor, 1954 (Acari: Phytoseiidae fed with castor bean (Ricinus communisL. pollen in laboratory conditions

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PP Marafeli

Full Text Available The predatory mite, Neoseiulus californicus(McGregor, 1954 (Acari: Phytoseiidae is one of the principal natural enemies of tetranychid mites in several countries, promoting efficient control of those mites in several food and ornamental crops. Pest attacks such as that of the spider mite, Tetranychus urticaeKoch, 1836 (Acari: Tetranychidae, is one of the problems faced by farmers, especially in the greenhouse, due to the difficulty of its control with the use of chemicals because of the development of fast resistance making it hard to control it. The objective of this work was to study the life history of the predatory mite N. californicus as a contribution to its mass laboratory rearing, having castor bean plant [Ricinus communis L. (Euphorbiaceae] pollen as food, for its subsequent use as a natural enemy of T. urticae on a cultivation of greenhouse rosebushes. The studies were carried out in the laboratory, at 25 ± 2°C of temperature, 70 ± 10% RH and a 14 hour photophase. The biological aspects and the fertility life table were appraised. Longevity of 32.9 days was verified for adult females and 40.4 days for males. The intrinsic rate of increase (rm was 0.2 and the mean generation time (T was 17.2 days. The population doubled every 4.1 days. The results obtained were similar to those in which the predatory mite N. californicus fed on T. urticae.

Overcompensation of herbivore reproduction through hyper-suppression of plant defenses in response to competition.

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Schimmel, Bernardus C J; Ataide, Livia M S; Chafi, Rachid; Villarroel, Carlos A; Alba, Juan M; Schuurink, Robert C; Kant, Merijn R

2017-06-01

Spider mites are destructive arthropod pests on many crops. The generalist herbivorous mite Tetranychus urticae induces defenses in tomato (Solanum lycopersicum) and this constrains its fitness. By contrast, the Solanaceae-specialist Tetranychus evansi maintains a high reproductive performance by suppressing tomato defenses. Tetranychus evansi outcompetes T. urticae when infesting the same plant, but it is unknown whether this is facilitated by the defenses of the plant. We assessed the extent to which a secondary infestation by a competitor affects local plant defense responses (phytohormones and defense genes), mite gene expression and mite performance. We observed that T. evansi switches to hyper-suppression of defenses after its tomato host is also invaded by its natural competitor T. urticae. Jasmonate (JA) and salicylate (SA) defenses were suppressed more strongly, albeit only locally at the feeding site of T. evansi, upon introduction of T. urticae to the infested leaflet. The hyper-suppression of defenses coincided with increased expression of T. evansi genes coding for salivary defense-suppressing effector proteins and was paralleled by an increased reproductive performance. Together, these observations suggest that T. evansi overcompensates its reproduction through hyper-suppression of plant defenses in response to nearby competitors. We hypothesize that the competitor-induced overcompensation promotes competitive population growth of T. evansi on tomato. © 2017 The Authors. New Phytologist © 2017 New Phytologist Trust.

The role of web sharing, species recognition and host-plant defence in interspecific competition between two herbivorous mite species.

Science.gov (United States)

Sato, Yukie; Alba, Juan M; Egas, Martijn; Sabelis, Maurice W

2016-11-01

When competing with indigenous species, invasive species face a problem, because they typically start with a few colonizers. Evidently, some species succeeded, begging an answer to the question how they invade. Here, we investigate how the invasive spider mite Tetranychus evansi interacts with the indigenous species T. urticae when sharing the solanaceous host plant tomato: do they choose to live together or to avoid each other's colonies? Both species spin protective, silken webs on the leaf surfaces, under which they live in groups of con- and possibly heterospecifics. In Spain, T. evansi invaded the non-crop field where native Tetranychus species including T. urticae dominated. Moreover, T. evansi outcompetes T. urticae when released together on a tomato plant. However, molecular plant studies suggest that T. urticae benefits from the local down-regulation of tomato plant defences by T. evansi, whereas T. evansi suffers from the induction of these defences by T. urticae. Therefore, we hypothesize that T. evansi avoids leaves infested with T. urticae whereas T. urticae prefers leaves infested by T. evansi. Using wild-type tomato and a mutant lacking jasmonate-mediated anti-herbivore defences, we tested the hypothesis and found that T. evansi avoided sharing webs with T. urticae in favour of a web with conspecifics, whereas T. urticae more frequently chose to share webs with T. evansi than with conspecifics. Also, T. evansi shows higher aggregation on a tomato plant than T. urticae, irrespective of whether the mites occur on the plant together or not.

Interactions between natural enemies: Effect of a predatory mite on transmission of the fungus Neozygites floridana in two-spotted spider mite populations.

Science.gov (United States)

Trandem, Nina; Berdinesen, Ronny; Pell, Judith K; Klingen, Ingeborg

2016-02-01

Introducing the predatory mite Phytoseiulus persimilis into two-spotted spider mite, Tetranychus urticae, populations significantly increased the proportion of T. urticae infected with the spider mite pathogen Neozygites floridana in one of two experiments. By the final sampling occasion, the number of T. urticae in the treatment with both the predator and the pathogen had declined to zero in both experiments, while in the fungus-only treatment T. urticae populations still persisted (20-40 T. urticae/subsample). Releasing P. persimilis into crops in which N. floridana is naturally present has the potential to improve spider mite control more than through predation alone. Copyright © 2016 Elsevier Inc. All rights reserved.

Urtica spp.: Phenolic composition, safety, antioxidant and anti-inflammatory activities.

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Carvalho, Ana Rita; Costa, Gustavo; Figueirinha, Artur; Liberal, Joana; Prior, João A V; Lopes, Maria Celeste; Cruz, Maria Teresa; Batista, Maria Teresa

2017-09-01

Urtica dioica and other less studied Urtica species (Urticaceae) are often used as a food ingredient. Fifteen hydroxycinnamic acid derivatives and sixteen flavonoids, flavone and flavonol-type glycosides were identified in hydroalcoholic extracts from aerial parts of Urtica dioica L., Urtica urens L. and Urtica membranacea using HPLC-PDA-ESI/MS n . Among them, the 4-caffeoyl-5-p-coumaroylquinic acid and three statin-like 3-hydroxy-3-methylglutaroyl flavone derivatives were identified for the first time in Urtica urens and U. membranacea respectively. Urtica membranacea showed the higher content of flavonoids, mainly luteolin and apigenin C-glycosides, which are almost absent in the other species studied. In vitro, Urtica dioica exhibited greater antioxidant activity but Urtica urens exhibited stronger anti-inflammatory potential. Interestingly, statin-like compounds detected in Urtica membranacea have been associated with hypocholesterolemic activity making this plant interesting for future investigations. None of the extracts were cytotoxic to macrophages and hepatocytes in bioactive concentrations (200 and 350μg/mL), suggesting their safety use in food applications. Copyright © 2017 Elsevier Ltd. All rights reserved.

A Laboratory Assessment of Two Local Strains of the Beauveria bassiana (Bals.) Vuill. against the Tetranychus urticae (Acari: Tetranychidae) and Their Potential as a Mycopesticide

Science.gov (United States)

Algur, Omer Faruk

2017-01-01

This study was conducted to assess highly pathogenic Beauveria bassiana isolates to be used in biocontrol and to determine their potentials as mycopesticide. For this purpose, two B. bassiana isolates, which were locally isolated from T. urticae, were chosen. Firstly, three suspensions were investigated at the degree of humidity of 65 ± 5% and 100% RH. Secondly, these strains were selected according to their tendency to mass production, tolerance to UV radiation, and capability of producing spore at the different temperatures. Finally, identification of the selected isolate was performed by using ITS rDNA analysis. Both tested fungal isolates were pathogenic to the T. urticae. Mycelial growths of isolate AT076 at 20°C and 30°C were found to be greater than isolate AT007. It was observed that isolate AT076 had more spore production with 1.61 × 107 spore/disc at 30°C and 44.33% germination after UV radiation for 15 min. The numbers of spores per 5 mm disk area for isolates AT076 and AT007 were found to be 1.2 × 106 and 1.0 × 106. These results show that isolate AT076 was more virulent and more UV-tolerant and had higher tendency to mass production compared to isolate AT007 against T. urticae. As a result of this study, isolate AT076 can be used in the biocontrol as mycopesticide. PMID:29250446

A Laboratory Assessment of Two Local Strains of the Beauveria bassiana (Bals. Vuill. against the Tetranychus urticae (Acari: Tetranychidae and Their Potential as a Mycopesticide

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Serkan Ortucu

2017-01-01

Full Text Available This study was conducted to assess highly pathogenic Beauveria bassiana isolates to be used in biocontrol and to determine their potentials as mycopesticide. For this purpose, two B. bassiana isolates, which were locally isolated from T. urticae, were chosen. Firstly, three suspensions were investigated at the degree of humidity of 65 ± 5% and 100% RH. Secondly, these strains were selected according to their tendency to mass production, tolerance to UV radiation, and capability of producing spore at the different temperatures. Finally, identification of the selected isolate was performed by using ITS rDNA analysis. Both tested fungal isolates were pathogenic to the T. urticae. Mycelial growths of isolate AT076 at 20°C and 30°C were found to be greater than isolate AT007. It was observed that isolate AT076 had more spore production with 1.61 × 107 spore/disc at 30°C and 44.33% germination after UV radiation for 15 min. The numbers of spores per 5 mm disk area for isolates AT076 and AT007 were found to be 1.2 × 106 and 1.0 × 106. These results show that isolate AT076 was more virulent and more UV-tolerant and had higher tendency to mass production compared to isolate AT007 against T. urticae. As a result of this study, isolate AT076 can be used in the biocontrol as mycopesticide.

Testing for reproductive interference in the population dynamics of two congeneric species of herbivorous mites

Science.gov (United States)

Sato, Y; Alba, J M; Sabelis, M W

2014-01-01

When phylogenetically close, two competing species may reproductively interfere, and thereby affect their population dynamics. We tested for reproductive interference (RI) between two congeneric haplo-diploid spider mites, Tetranychus evansi and Tetranychus urticae, by investigating their interspecific mating and their population dynamics when they competed on the same plants. They are both pests of tomato, but differ in the host plant defences that they suppress or induce. To reduce the effect of plant-mediated interaction, we used a mutant tomato plant lacking jasmonate-mediated anti-herbivore defences in the competition experiment. In addition, to manipulate the effect of RI, we introduced founder females already mated with conspecific males in mild RI treatments or founder, virgin females in strong RI treatments (in either case together with heterospecific and conspecific males). As females show first-male sperm precedence, RI should occur especially in the founder generation under strong RI treatments. We found that T. urticae outcompeted T. evansi in mild, but not in strong RI treatments. Thus, T. evansi interfered reproductively with T. urticae. This result was supported by crossing experiments showing frequent interspecific copulations, strong postmating reproductive isolation and a preference of T. evansi males to mate with T. urticae (instead of conspecific) females, whereas T. urticae males preferred conspecific females. We conclude that interspecific mating comes at a cost due to asymmetric mate preferences of males. Because RI by T. evansi can improve its competitiveness to T. urticae, we propose that RI partly explains why T. evansi became invasive in Europe where T. urticae is endemic. PMID:24865602

Temperature-dependent development and reproductive traits of Tetranychus macfarlanei (Acari: Tetranychidae)

DEFF Research Database (Denmark)

Ullah, Mohammad Shaef; Haque, Md. Ahsanul; Nachman, Gösta

2012-01-01

Development and reproductive traits of Tetranychus macfarlanei Baker & Pritchard (Acari: Tetranychidae) were investigated on kidney bean, Phaseolus vulgaris L., at eleven constant temperatures. Tetranychus macfarlanei was able to develop and complete its life cycle at temperatures ranging from 17...

Comparing chemical and biological control strategies for twospotted spider mites (Acari: Tetranychidae) in commercial greenhouse production of bedding plants.

Science.gov (United States)

Opit, George P; Perret, Jamis; Holt, Kiffnie; Nechols, James R; Margolies, David C; Williams, Kimberly A

2009-02-01

Efficacy, costs, and impact on crop salability of various biological and chemical control strategies for Tetranychus urticae Koch (Acari: Tetranychidae) were evaluated on mixed plantings of impatiens, Impatiens wallerana Hook.f (Ericales: Balsaminaceae), and ivy geranium, Pelargonium peltatum (1.) L'Hér. Ex Aiton (Geraniales: Geraniaceae), cultivars in commercial greenhouses. Chemical control consisting of the miticide bifenazate (Floramite) was compared with two biological control strategies using the predatory mite Phytoseiulus persimilis Athias-Henriot (Acari: Phytoseiidae). Treatments were 1) a single, early application of bifenazate; 2) a single, early release of predatory mites at a 1:4 predator:pest ratio based on leaf samples to estimate pest density; 3) a weekly release of predatory mites at numbers based on the area covered by the crop; and 4) an untreated control. T. urticae populations were monitored for 3 wk after the earliest treatment. When plants were ready for market, their salability was estimated. Bifenazate and density-based P. persimilis treatments effectively reduced T. urticae numbers starting 1 wk after plants had been treated, whereas the scheduled, area-based P. persimilis treatment had little or no effect. The percentage of flats that could be sold at the highest market wholesale price ranged from 15 to 33%, 44 to 86%, 84 to 95%, and 92 to 100%, in the control, weekly area-based P. persimilis, bifenazate, and single density-based P. persimilis treatments, respectively. We have shown that in commercial greenhouse production of herbaceous ornamental bedding plants, estimating pest density to determine the appropriate number of predators to release is as effective and offers nearly the same economic benefit as prophylactic use of pesticides.

Peter Koch: wizard of wood use

Science.gov (United States)

M.E. Lora

1978-01-01

Like his pioneer forefathers, Peter Koch sees opportunity where others see obstacles. And his vision is helping to reshape the wood industry. Since 1963 Koch has directed research on processing southern woods for the U.S. Forest Service's Southern Forest Experiment Station in Pineville, Louisiana. In that time, he has invented six revolutionary machines, developed...

Effects of Urtica dioica extract on lipid profile in hypercholesterolemic rats.

Science.gov (United States)

Nassiri-Asl, Marjan; Zamansoltani, Farzaneh; Abbasi, Esmail; Daneshi, Mohammad-Mehdi; Zangivand, Amir-Abdollah

2009-05-01

To investigate the effects of extract of Urtica dioica, a perennial herb in Iran, on lipid profile in hypercholesterolemic rats. The effects of Urtica dioica extract were tested by using it as a supplement in a high-cholesterol diet. Male rats were fed a high cholesterol diet (10 mL/kg) for 4 weeks with Urtica dioica extract (100 or 300 mg/kg) or 10 mg/kg lovastatin supplementation to study the hypocholesterolemic effects of Urtica dioica on plasma lipid levels, hepatic enzymes activities, and liver histopathological changes. Urtica dioica extract at 100 and 300 mg/kg significantly reduced the levels of total cholesterol (TC), and low-density lipoprotein-cholesterol (LDL-C) and also markedly decreased liver enzymes and weight in animals with a high cholesterol diet. Hematoxylin and eosin staining showed that in the 100 mg/kg extract of Urtica dioica group, the appearance of the liver cells was similar to the control group, and steatosis and inflammation were not found. In the 300 mg/kg extract of Urtica dioica group, mild steatosis was observed but mononuclear inflammatory infiltration was not found. The hepatic histopathological results reflect the correlation of Urtica dioica extract with both liver weight and the levels of plasma TC and LDL-C. These results indicate that Urtica dioica extract has hypocholesterolemic effects in the animal model.

Effectiveness of electron irradiation as a quarantine treatment of cut flowers

International Nuclear Information System (INIS)

Hayashi, T.; Todoriki, S.; Nakakita, H.; Dohino, T.; Tanabe, K.

1999-01-01

The effects of electron beams on spider mite (Tetranychus urticae) and flour beetle (Tribolium freemani) were slightly smaller than those of gamma-rays. 'Soft-electrons' (low-energy electrons) at an energy of 170 keV inactivated eggs, larvae, pupae, and adults of the flour beetle. Electron beams at doses up to 400 Gy killed or sterilized all the pests for cut flowers tested; spider mite (Tetranychus urticae), mealybug (Pseudococcus comstocki), leaf miner (Liriomyza trifolii), thrips (Thrips palmi, Thrips tabaci), cutworm (Spodoptera litura), and aphid (Myzus persicae). Carnation, alstromeria, gladiolus, tulip, statice, stock, dendrobium, prairie gentian, oncidium, campanula, gloriosa, fern, gypsophila, freesia, lobelia, triteleia, and gerbera were resistant to radiation, while chrysanthemum, rose, lily, calla, antherium, sweet pea, and iris were sensitive. Radiation-induced deterioration of chrysanthemum could be prevented by post-irradiation treatment with commercial preservative solutions or sugar solutions. (author)

The Bibliographic studies on Scolopendra subspinipes mutilans L. Koch

Directory of Open Access Journals (Sweden)

Go, Gang-Hun

2002-02-01

Full Text Available Objective: Through the literature on the effect of Scolopendra subspinipes mutilans L. Koch, we are finding out the clinical possibility and revealing the more effective to untractable disease. Method: We investigated the literatures of Oriental Medicine and experimental reports about Scolopendra subspinipes mutilans L. Koch. Results: 1.The taste of Scolopendra subspinipes mutilans L. Koch is hot, wann and toxic, and the effect is dispelling wind, spasmolytic action and detoxication so it has been used for C.V.A, facial palsy, numbness of hands and feet, wounds and arthritis. 2. A toxic constituent of Scolopendra subspinipes mutilans L. Koch is mainly located in the 1st limbs, and we can prevent toxic symptoms, if taken a dosage moderately. 3. The pharmacological action of Scolopendra subspinipes mutilans L. Koch is anti-convulsive action, analgesic action, lowering blood pressure, anti-inflammatory action, anti-tumor action and microbe inhibition. On the study of Scolopendra subspinipes mutilans L. Koch, we thought it is effective to intractable disease, and it may be needed variable studies on toxicity and clinical effects.

The Koch curve as a smooth manifold

International Nuclear Information System (INIS)

Epstein, Marcelo; Sniatycki, Jedrzej

2008-01-01

We show that there exists a homeomorphism between the closed interval [0,1] is contained in R and the Koch curve endowed with the subset topology of R 2 . We use this homeomorphism to endow the Koch curve with the structure of a smooth manifold with boundary

Pathogenecity of Beauveria bassiana and Metarhizium anisopliae ...

African Journals Online (AJOL)

two spotted spider mites, Tetranychus urticae, effect of temperature on virulence, as well as ... It has become a big challenge to maintain quality of products and compete in ... Data were collected on the number of hatched and un-hatched eggs.

Herbivory induces systemic production of plant volatiles that attract predators of the herbivore: extraction of endogenous elicitor.

NARCIS (Netherlands)

Dicke, M.; Baarlen, van P.; Wessels, R.; Dijkman, H.

1993-01-01

It was previously shown that in response to infestation by spider mites (Tetranychus urticae), lima bean plants produce a volatile herbivoreinduced synomone that attracts phytoseiid mites (Phytoseiulus persimilis) that are predators of the spider mites. The production of predator-attracting

Essential oil composition and acaricidal activity of Schinus terebinthifolius from Atlantic Forest of Pernambuco, Brazil against Tetranychus urticae.

Science.gov (United States)

do Nascimento, Aline Fonseca; da Camara, Claudio Augusto Gomes; de Moraes, Marcílio Martins; Ramos, Clécio Souza

2012-01-01

The compositions of the essential oils from unripe (UFr) and ripe (RFr) fruits of Schinus terebinthifolius were analyzed by GC and GC/MS. The major compound identified in both oils was limonene (UFr = 44.1 +/- 1.3%; RFr = 31.8 +/- 1.2%), followed by alpha-phellandrene (15.7 +/- 0.4%) in the UFr oil and thujene (21.7 +/- 0.9%) in the RFr oil. Repellent and toxicity activities of the two oils were also evaluated, and the results compared with eugenol. The UFr oil was more active in the fumigation tests (LC50 = 1.46 microL/L of air), whereas the RFr oil was more active in the sealed dishes (SD) than open dishes (OD) contact assay (LC50 = 3.04 microL/cm2) and not significantly different from eugenol. Both oils exhibited significant repellent activity comparable with that of eugenol. The results suggest that the repellent activity of these oils in association with its toxicity could be a great advantage for the integrated management of T. urticae.

Permanent Genetic Resources added to Molecular Ecology Resources database 1 January 2009-30 April 2009.

Science.gov (United States)

Abercrombie, L G; Anderson, C M; Baldwin, B G; Bang, I C; Beldade, R; Bernardi, G; Boubou, A; Branca, A; Bretagnolle, F; Bruford, M W; Buonamici, A; Burnett, R K; Canal, D; Cárdenas, H; Caullet, C; Chen, S Y; Chun, Y J; Cossu, C; Crane, C F; Cros-Arteil, S; Cudney-Bueno, R; Danti, R; Dávila, J A; Della Rocca, G; Dobata, S; Dunkle, L D; Dupas, S; Faure, N; Ferrero, M E; Fumanal, B; Gigot, G; González, I; Goodwin, S B; Groth, D; Hardesty, B D; Hasegawa, E; Hoffman, E A; Hou, M L; Jamsari, A F J; Ji, H J; Johnson, D H; Joseph, L; Justy, F; Kang, E J; Kaufmann, B; Kim, K S; Kim, W J; Koehler, A V; Laitung, B; Latch, P; Liu, Y D; Manjerovic, M B; Martel, E; Metcalfe, S S; Miller, J N; Midgley, J J; Migeon, A; Moore, A J; Moore, W L; Morris, V R F; Navajas, M; Navia, D; Neel, M C; De Nova, P J G; Olivieri, I; Omura, T; Othman, A S; Oudot-Canaff, J; Panthee, D R; Parkinson, C L; Patimah, I; Pérez-Galindo, C A; Pettengill, J B; Pfautsch, S; Piola, F; Potti, J; Poulin, R; Raimondi, P T; Rinehart, T A; Ruzainah, A; Sarver, S K; Scheffler, B E; Schneider, A R R; Silvain, J F; Siti Azizah, M N; Springer, Y P; Stewart, C N; Sun, W; Tiedemann, R; Tsuji, K; Trigiano, R N; Vendramin, G G; Wadl, P A; Wang, L; Wang, X; Watanabe, K; Waterman, J M; Weisser, W W; Westcott, D A; Wiesner, K R; Xu, X F; Yaegashi, S; Yuan, J S

2009-09-01

This article documents the addition of 283 microsatellite marker loci to the Molecular Ecology Resources Database. Loci were developed for the following species: Agalinis acuta; Ambrosia artemisiifolia; Berula erecta; Casuarius casuarius; Cercospora zeae-maydis; Chorthippus parallelus; Conyza canadensis; Cotesia sesamiae; Epinephelus acanthistius; Ficedula hypoleuca; Grindelia hirsutula; Guadua angustifolia; Leucadendron rubrum; Maritrema novaezealandensis; Meretrix meretrix; Nilaparvata lugens; Oxyeleotris marmoratus; Phoxinus neogaeus; Pristomyrmex punctatus; Pseudobagrus brevicorpus; Seiridium cardinale; Stenopsyche marmorata; Tetranychus evansi and Xerus inauris. These loci were cross-tested on the following species: Agalinis decemloba; Agalinis tenella; Agalinis obtusifolia; Agalinis setacea; Agalinis skinneriana; Cercospora zeina; Cercospora kikuchii; Cercospora sorghi; Mycosphaerella graminicola; Setosphaeria turcica; Magnaporthe oryzae; Cotesia flavipes; Cotesia marginiventris; Grindelia Xpaludosa; Grindelia chiloensis; Grindelia fastigiata; Grindelia lanceolata; Grindelia squarrosa; Leucadendron coniferum; Leucadendron salicifolium; Leucadendron tinctum; Leucadendron meridianum; Laodelphax striatellus; Sogatella furcifera; Phoxinus eos; Phoxinus rigidus; Phoxinus brevispinosus; Phoxinus bicolor; Tetranychus urticae; Tetranychus turkestani; Tetranychus ludeni; Tetranychus neocaledonicus; Tetranychus amicus; Amphitetranychus viennensis; Eotetranychus rubiphilus; Eotetranychus tiliarium; Oligonychus perseae; Panonychus citri; Bryobia rubrioculus; Schizonobia bundi; Petrobia harti; Xerus princeps; Spermophilus tridecemlineatus and Sciurus carolinensis. © 2009 Blackwell Publishing Ltd.

A comparative study of development and demographic parameters of Tetranychus merganser and Tetranychus kanzawai (Acari: Tetranychidae) at different temperatures

DEFF Research Database (Denmark)

Ullah, M. S.; Moriya, D.; Badii, M.H.

2011-01-01

We investigated the effect of temperature on development and demographic parameters such as the intrinsic rate of natural increase (rm) of the two spider mite species Tetranychus merganser Boudreaux and T. kanzawai Kishida at eleven constant temperatures ranging from 15 to 40C at intervals of 2.5...

Alternative phenotypes of male mating behaviour in the two-spotted spider mite

NARCIS (Netherlands)

Sato, Y.; Sabelis, M.W.; Egas, M.; Faraji, F.

2013-01-01

Severe intraspecific competition for mates selects for aggressive individuals but may also lead to the evolution of alternative phenotypes that do not act aggressively, yet manage to acquire matings. The two-spotted spider mite, Tetranychus urticae, shows male mate-guarding behaviour and male-male

Jasmonic acid is a key regulator of spider mite-induced volatile terpenoid and methyl salicylate emission in tomato

NARCIS (Netherlands)

Ament, K.; Kant, M.R.; Sabelis, M.W.; Haring, M.A.; Schuurink, R.C.

2004-01-01

The tomato (Lycopersicon esculentum) mutant def-1, which is deficient in induced jasmonic acid (JA) accumulation upon wounding or herbivory, was used to study the role of JA in the direct and indirect defense responses to phytophagous mites (Tetranychus urticae). In contrast to earlier reports,

Pathogenecity of Beauveria bassiana and Metarhizium anisopliae ...

African Journals Online (AJOL)

emulsifiable formulation on two-spotted spider mite, T. urticae. Weibin and. Mingguang (2004) found that both B. bassiana and Paecilomyces fumosoroseus infections decreased the hatch rates of Tetranychus cinnanarinus eggs and the higher the conidial concentrations resulted in greater reduction in the hatch rates.

Lima bean leaves exposed to herbivore-induced conspecific plant volatiles attract herbivores in addition to carnivores

NARCIS (Netherlands)

Horiuchi, J.I.; Arimura, G.I.; Ozawa, R.; Shimoda, T.; Dicke, M.; Takabayashi, J.; Nishioka, T.

2003-01-01

We tested the response of the herbivorous mite Tetranychus urticae to uninfested lima bean leaves exposed to herbivore-induced conspecific plant volatiles by using a Y-tube olfactometer. First, we confirmed that exposed uninfested leaves next to infested leaves were more attractive to carnivorous

A functional response model of a predator population foraging in a patchy habitat

DEFF Research Database (Denmark)

Nachman, Gösta

2006-01-01

persimis and Tetranychus urticae inhabiting greenhouse cucumbers. 6. The model fits empirical data quite well and much better than if prey and predators were assumed to be evenly distributed among patches, or if the predators were distributed independently of the prey. 7. The analyses show...

Spider mite control and resistance management: does a genome help?

NARCIS (Netherlands)

Van Leeuwen, T.; Dermauw, W.; Grbic, M.; Tirry, L.; Feyereisen, R.

2012-01-01

The complete genome of the two-spotted spider mite, Tetranychus urticae, has been reported. This is the first sequenced genome of a highly polyphagous and resistant agricultural pest. The question as to what the genome offers the community working on spider mite control is addressed.

The response of Phytoseiulus persimilis to spider mite-induced volatiles from gerbera: influence of starvation and experience

NARCIS (Netherlands)

Krips, O.E.; Willems, P.E.I.; Gols, R.; Posthumus, M.A.; Dicke, M.

1999-01-01

When leaves of the ornamental crop Gerbera jamesonii are damaged by the spider mite Tetranychus urticae, they produce many volatile compounds in large quantities. Undamaged gerbera leaves produce only a few volatiles in very small quantities. In the headspace of spider mite-damaged gerbera leaves

Methyl salicylate production in tomato affects biotic interactions

NARCIS (Netherlands)

Ament, K.; Krasikov, V.; Allmann, S.; Rep, M.; Takken, F.L.W.; Schuurink, R.C.

2010-01-01

The role of methyl salicylate (MeSA) production was studied in indirect and direct defence responses of tomato (Solanum lycopersicum) to the spider mite Tetranychus urticae and the root-invading fungus Fusarium oxysporum f. sp. lycopersici, respectively. To this end, we silenced the tomato gene

[Richard Koch's life in national socialism and in Soviet emigration].

Science.gov (United States)

Boltres, Daniela; Töpfer, Frank; Wiesing, Urban

2006-01-01

The Jewish historian and theorist of medicine, Richard Koch, teaching in Frankfurt/Main, fled in 1936 from National Socialist Germany to the USSR where he lived in the Caucasian spa Essentuki until his death in 1949. Here he worked as a doctor and continued his scientific work, especially on the foundations of medicine in natural philosophy. None of his works of this time were published. Koch was a scientific outsider in the USSR, and he was aware of this. However, he tried to make his views compatible with official doctrines. In 1947 he lost his employment at the medical clinic of Essentuki, and his material situation grew worse. It is still an open question whether this development was related to an increasingly anti-Jewish atmosphere in the USSR that was linked with the Stalinist "purges", as Koch himself appeared to believe. Before his flight from Germany Koch did not show any tendency towards communism or the political left at all. His attitude towards Soviet society and Stalin was mixed: cautious criticism was accompanied by strong expressions of commitment to Stalin and Koch's new Socialist home. The question to what extent Koch's comments showed his true convictions must remain without a definite answer. At least in part they can be understood as precautions in threatening circumstances. The opportunity of a remigration to Germany after 1945, however, was turned down by Koch.

Recognising one's enemies : a functional approach to risk assessment by prey

NARCIS (Netherlands)

Grostal, P.; Dicke, M.

2000-01-01

Little has been done to compare the relative importance of various mechanisms through which prey assess the potential risk from natural enemies. We used predator-naive spider mites (Tetranychus urticae, Tetranychidae) to (1) compare the responses of prey to chemical cues from enemy and non-enemy

Induction of indirect defence against spider-mites in uninfested lima bean leaves.

NARCIS (Netherlands)

Takabayashi, J.; Dicke, M.; Posthumus, M.A.

1991-01-01

Headspace analyses of uninfested Lima bean (Phaseolus lunatus) leaves show an absence of or only trace amounts of the terpenoids (E)--ocimene and (E)-4,8-dimethyl-1,3,7-nonatriene. Upon infestation by two-spotted spider-mites (Tetranychus urticae), Lima bean leaves produce (E)--ocimene and

Evaluation of airborne methyl salicylate for improved conservation biological control of two-spotted spider mites and hop aphid in Oregon hop yards

Science.gov (United States)

The use of synthetic herbivore-induced plant volatiles (HIPV) to attract natural enemies has received interest as a tool to enhance conservation biological control (CBC). Methyl salicylate (MeSA) is a HIPV that is attractive to several key predators of two-spotted spider mite, Tetranychus urticae K...

Testing for non-target effects of spinosad on twospotted spider mites and their predator Phytoseiulus persimilis under greenhouse conditions.

Science.gov (United States)

Holt, Kiffnie M; Opit, George P; Nechols, James R; Margolies, David C

2006-01-01

The compatibility of the selective insecticide spinosad (Conserve SC), at rates recommended for thrips control in greenhouses, with release of the predatory mite Phytoseiulus persimilis Athias-Henriot (Acari: Phytoseiidae) to control spider mites, was investigated in a crop of ivy geranium Pelargonium peltatum, cultivar 'Amethyst 96.' Plants were inoculated with twospotted spider mites, Tetranychus urticae Koch (Acari: Tetranychidae), 2 weeks before treatments were applied. There were three treatment variables, each at two levels: predators (released or not), spray application (water or Conserve SC at 2 ml/3.79 l), and timing of spray (1 day before or after predators were released). Twospotted spider mite populations then were sampled twice each week over a three-week period. The application or timing of spinosad had no effect on the ability of the predator to reduce the population of spider mites. Spider mite populations in the no-predator treatment continued to expand over the course of the experiment, while those in the predator-release treatment declined. We conclude that P. persimilis can be used in conjunction with spinosad on ivy geraniums without causing obvious detrimental effects to this predator or leading to a reduction in biological control.

Búsqueda y reconocimiento de los enemigos naturales y hospedantes alternos de las principales plagas. En flores bajo invernadero en la sabana de Bogotá

Directory of Open Access Journals (Sweden)

Martha E. Andrade

1989-01-01

Full Text Available Las plagas que atacan cultivos de llores bajo invernadero son cada vez más importantes por la gravedad de su daño y por la alta densidad con que suelen presentarse. Para su control se ha acudido principalmente a la utilización de productos químicos, lo cual conduce a un aumento en los costos de producción, a contaminar el medio ambiente, a afectar la salud humana y a crear resistencia de los insectos a los insecticidas. Debido a esto, es necesario incluír dentro de los programas de control a los reguladores naturales de las plagas: parasitoides, depredadores y microorganismos entornógenos. En el presente trabajo se registran los enemigos naturales más importantes de las principales plagas en llores bajo invernadero (crisantemo, rosa y clavel: Liriomyza huidobrensis Blanchard, L. trifolii Burgess (Diptera: Agrornyzídae; Myzuz persicae Sulzer (Homoptera: Aphididae; Tetranychus urticae Koch y T. cinnabarinus Boísduval (Acarina: Tetranychidae; también se señalan las plantas hospedantes alternas presentes en las localidades donde se realizó la investigación.

Evaluation of airborne methyl salicylate for improved conservation biological control of two-spotted spider mite and hop aphid in Oregon hop yards.

Science.gov (United States)

Woods, J L; James, D G; Lee, J C; Gent, D H

2011-12-01

The use of synthetic herbivore-induced plant volatiles (HIPV) to attract natural enemies has received interest as a tool to enhance conservation biological control (CBC). Methyl salicylate (MeSA) is a HIPV that is attractive to several key predators of two-spotted spider mite, Tetranychus urticae Koch (Acari: Tetranychidae), and hop aphid, Phorodon humuli (Schrank) (Homoptera: Aphididae). A 2-year study was conducted to evaluate the recommended commercial use of MeSA in hop yards in Oregon. Slow-release MeSA dispensers were stapled to supporting poles in 0.5 ha plots and these plots were compared to a paired non-treated plot on each of three farms in 2008 and 2009. Across both years, there was a trend for reduced (range 40-91%) mean seasonal numbers of T. urticae in five of the six MeSA-baited plots. Stethorus spp., key spider mite predators, tended to be more numerous in MeSA-baited plots compared to control plots on a given farm. Mean seasonal densities of hop aphid and other natural enemies (e.g., Orius spp. and Anystis spp.) were similar between MeSA-treated and control plots. Variability among farms in suppression of two-spotted spider mites and attraction of Stethorus spp. suggests that the use of MeSA to enhance CBC of spider mites in commercial hop yards may be influenced by site-specific factors related to the agroecology of individual farms or seasonal effects that require further investigation. The current study also suggests that CBC of hop aphid with MeSA in this environment may be unsatisfactory.

Isolation and identification of volatile kairomone that affects acarine predator-prey interactions: involvement of host plant in its production.

NARCIS (Netherlands)

Dicke, M.; Beek, van T.A.; Posthumus, M.A.; Dom, Ben N.; Bokhoven, van H.; Groot, de Ae.

1990-01-01

A volatile kairomone emitted from lima bean plants (Phaseolus lunatus) infested with the spider miteTetranychus urticae, was collected on Tenax-TA and analyzed with GC-MS. Two components were identified as the methylene monoterpene (3E)-4,8-dimethyl-1,3,7-nonatriene and the methylene sesquiterpene

The predatory mite Phytoseiulus persimilis does not perceive odor mixtures as strictly elemental objects

NARCIS (Netherlands)

van Wijk, M.; de Bruijn, P.J.A.; Sabelis, M.W.

2010-01-01

Phytoseiulus persimilis is a predatory mite that in absence of vision relies on the detection of herbivore-induced plant odors to locate its prey, the two-spotted spider-mite Tetranychus urticae. This herbivorous prey is feeding on leaves of a wide variety of plant species in different families. The

Mapping Koch curves into scale-free small-world networks

International Nuclear Information System (INIS)

Zhang Zhongzhi; Gao Shuyang; Zhou Shuigeng; Chen Lichao; Zhang Hongjuan; Guan Jihong

2010-01-01

The class of Koch fractals is one of the most interesting families of fractals, and the study of complex networks is a central issue in the scientific community. In this paper, inspired by the famous Koch fractals, we propose a mapping technique converting Koch fractals into a family of deterministic networks called Koch networks. This novel class of networks incorporates some key properties characterizing a majority of real-life networked systems-a power-law distribution with exponent in the range between 2 and 3, a high clustering coefficient, a small diameter and average path length and degree correlations. Besides, we enumerate the exact numbers of spanning trees, spanning forests and connected spanning subgraphs in the networks. All these features are obtained exactly according to the proposed generation algorithm of the networks considered. The network representation approach could be used to investigate the complexity of some real-world systems from the perspective of complex networks.

Computer-assisted estimation of leaf damage caused by spider mites

Czech Academy of Sciences Publication Activity Database

Škaloudová, B.; Křivan, Vlastimil; Zemek, Rostislav

2006-01-01

Roč. 53, č. 2, (2006), s. 81-91 ISSN 0168-1699 R&D Projects: GA AV ČR(CZ) IAA6007303 Institutional research plan: CEZ:AV0Z50070508 Keywords : Tetranychus urticae * Acari * Tetranychidae Subject RIV: GF - Plant Pathology, Vermin, Weed, Plant Protection Impact factor: 0.851, year: 2006

Proměnlivost druhu Urtica dioica na území ČR

OpenAIRE

Rejlová, Ludmila

2014-01-01

The genus Urtica L. is represented by three species occurring in the area of the Czech Republic. The most common Urtica dioica L. represents a highly variable group with number of intraspecific taxa. The most common source of variability in Urtica dioica is probably polyploidy (min. 2 ploidy levels - 2x and 4x). Another source of the variation in this species is dioecy. A small percentage of individuals in dioecious populations are actually monoecious. The study of these individuals can poten...

Random walks on generalized Koch networks

International Nuclear Information System (INIS)

Sun, Weigang

2013-01-01

For deterministically growing networks, it is a theoretical challenge to determine the topological properties and dynamical processes. In this paper, we study random walks on generalized Koch networks with features that include an initial state that is a globally connected network to r nodes. In each step, every existing node produces m complete graphs. We then obtain the analytical expressions for first passage time (FPT), average return time (ART), i.e. the average of FPTs for random walks from node i to return to the starting point i for the first time, and average sending time (AST), defined as the average of FPTs from a hub node to all other nodes, excluding the hub itself with regard to network parameters m and r. For this family of Koch networks, the ART of the new emerging nodes is identical and increases with the parameters m or r. In addition, the AST of our networks grows with network size N as N ln N and also increases with parameter m. The results obtained in this paper are the generalizations of random walks for the original Koch network. (paper)

Asymptotic analysis of a von Koch beam

International Nuclear Information System (INIS)

Carpinteri, Alberto; Pugno, Nicola; Sapora, Alberto

2009-01-01

Fractal geometry is used in diverse research areas, being an useful tool in describing the mechanical behaviour of natural and man-made structures. In this paper, the structural behaviour of a von Koch cantilever beam is analyzed in the small deformations regime. Analytical recursive formulae for the strain energy scaling are derived, which have been found in good agreement with numerical simulations. Energy considerations suggest a peculiar scaling for the beam rigidity in order to prevent compliance divergence. The results are then extended to evaluate the stiffness matrix of a von Koch beam.

Chemical composition and acaricidal activity of the leaf and fruit essential oils of Protium heptaphyllum (Aubl. Marchand (Burseraceae Composição química e atividade acaricida do óleo essencial das folhas e frutos de Protium heptaphyllum (Aubl. Marchand (Burseraceae

Directory of Open Access Journals (Sweden)

Wendel José Teles Pontes

2007-01-01

Full Text Available Essential oils from leaves and fruits of Protiumheptaphyllum collected in Tamandaré beach Pernambuco/Brazil were analysed by GC/MS and tested for toxicity and repellent effect against the two spotted spider mite (Tetranychus urticae. The major constituent identified in the fruits was alpha-terpinene (47.6 % whereas oil from leaf contained mainly sesquiterpenes such as 9-epi-caryophyllene (21.4 %, trans-isolongifolanone (10.7 % and 14-hydroxi-9-epi-caryophyllene (16.7 %. The fruit oil was found to be more effective against the mite when compared to the leaf oil. Both showed mortality properties and oviposition deterrence in higher concentration (10 µl.l-1 air, but only the essential oil from fruits induced repellence on T. urticae.O óleo essencial das folhas e frutos de Protiumheptaphyllum coletada em Tamandaré-Pernambuco foi analisado por CG/EM e testado sua toxicidade e efeito repelente contra ácaro rajado (Tetranychus urticae. O constituinte majoritário identificado nos frutos foi alfa-terpineno (47,6 % enquanto que nas folhas foram os sesquiterpenos 9-epi-cariofileno (21,4 %, trans-isolongifolanona (10,7 % and 14-hidroxi-9-epi-cariofileno (16,7 %. O óleo dos frutos foi mais eficiente contra o ácaro, comparado com o óleo das folhas. Ambos os óleos revelaram propriedades de mortalidade e deterrência de oviposição na maior concentração (10 µl.l-1 air e apenas o óleo essencial dos frutos induziu repelência no T. urticae.

Effects of Beauveria bassiana on predation and behavior of the predatory mite Phytoseiulus persimilis.

Science.gov (United States)

Wu, Shengyong; Xing, Zhenlong; Sun, Weinan; Xu, Xuenong; Meng, Ruixia; Lei, Zhongren

2018-03-01

Determination of intraguild interactions between entomopathogens and predators is important when attempting to use a combination of these two natural enemy groups for biological control of their shared arthropod pest species. This study assessed the effects of Beauveria bassiana on the predation and associated behavior of the predatory mite, Phytoseiulus persimilis, against Tetranychus urticae. The functional response tests showed that P. persimilis exhibited a Holling type II response on the spider mite, Tetranychus urticae, when treated with either a B. bassiana or Tween-80 suspension. There were no significant differences between the treatments in the number of T. urticae consumed. The laboratory choice test indicated that P. persimilis displayed a significant avoidance response to B. bassiana on bean leaves immediately following spray application. They also spent significantly longer time in self-grooming behavior on leaf disks sprayed with fungal conidia than on discs treated with Tween-80. There were no significant differences in the predation rates on T. urticae eggs between the different treatments. The potted plant investigations indicated that P. persimilis showed significant aversion behavior to the initial fungal spray, but gradually dispersed over the entire bean plants. Observations using scanning electron microscopy revealed that fungal conidia were attached to the body of P. persimilis after mounting the leaf disk treated with B. bassiana, which would account for its varied behavioral responses. Our study suggests that fungal spray did not affect the predation capability of P. persimilis and poses a negligible risk to their behavior. Copyright © 2018 Elsevier Inc. All rights reserved.

Spatiotemporal heterogeneity of tomato induced defense responses affects spider mite performance and behavior.

Science.gov (United States)

Schimmel, Bernardus C J; Ataide, Livia M S; Kant, Merijn R

2017-10-03

When feeding from tomato (Solanum lycopersicum), the generalist spider mite Tetranychus urticae induces jasmonate (JA)- and salicylate (SA)-regulated defense responses that hamper its performance. The related T. evansi, a Solanaceae-specialist, suppresses these defenses, thereby upholding a high performance. On a shared leaf, T. urticae can be facilitated by T. evansi, likely via suppression of defenses by the latter. Yet, when infesting the same plant, T. evansi outcompetes T. urticae. Recently, we found that T. evansi intensifies suppression of defenses locally, i.e., at its feeding site, after T. urticae mites were introduced onto adjacent leaf tissue. This hyper-suppression is paralleled by an increased oviposition rate of T. evansi, probably promoting its competitive population growth. Here we present additional data that not only provide insight into the spatiotemporal dynamics of defense induction and suppression by mites, but that also suggest T. evansi to manipulate more than JA and SA defenses alone.

Evaluation of a root extract gel from Urtica dioica (Urticaceae) as ...

African Journals Online (AJOL)

Purpose: To develop and characterize an herbal gel prepared from methanol root extract of Urtica dioica (Urticaceae) (Stinging nettle) for the treatment of arthritis in mice. Methods: A methanol root extract from Urtica dioica was prepared, and a gel was then prepared using Carbopol 934. The prepared gel was subjected to ...

Urtica dioica for treatment of benign prostatic hyperplasia: a prospective, randomized, double-blind, placebo-controlled, crossover study.

Science.gov (United States)

Safarinejad, Mohammad Reza

2005-01-01

To determine the effects of therapy with Urtica dioica for symptomatic relief of lower urinary tract symptoms (LUTS) secondary to benign prostatic hyperplasia (BPH). A 6-month, double-blind, placebo-controlled, randomized, partial crossover, comparative trial of Urtica dioica with placebo in 620 patients was conducted. Patients were evaluated using the International Prostate Symptom Score (IPSS), the maximum urinary flow rate (Qmax), postvoid residual urine volume (PVR), Serum Prostatic- Specific Antigen (PSA), testosterone levels, and prostate size. At the end of 6-month trial, unblinding revealed that patients who initially received the placebo were switched to Urtica dioica. Both groups continued the medication up to 18 months. 558 patients (90%) completed the study (287/305, 91% in the Urtica dioica group, and 271/315, 86% in the placebo group). By intention- to-treat analysis, at the end of 6-month trial, 232 (81%) of 287 patients in the Urtica dioica group reported improved LUTS compared with 43 (16%) of 271 patients in the placebo group (P Urtica dioica and from 19.2 to 17.7 with placebo (P = 0.002). Peak flow rates improved by 3.4 mL/s for placebo recipients and by 8.2 mL/s for treated patients (P Urtica dioica group, PVR decreased from an initial value of 73 to 36 mL (P Urtica dioica group (from 40.1 cc initially to 36.3 cc; P Urtica dioica have beneficial effects in the treatment of symptomatic BPH. Further clinical trials should be conducted to confirm these results before concluding that Urtica dioica is effective.

Comparison of single and combination treatments of Phytoseiulus persimilis, Neoseiulus californicus, and Acramite (bifenazate) for control of twospotted spider mites in strawberries.

Science.gov (United States)

Rhodes, Elena M; Liburd, Oscar E; Kelts, Crystal; Rondon, Silvia I; Francis, Roger R

2006-01-01

Greenhouse and field experiments were conducted from 2003 to 2005 to determine the effectiveness of combining releases of two predatory mite species, Phytoseiulus persimilis Athias-Henriot and Neoseiulus californicus (McGregor), and a reduced-risk miticide, Acramite (bifenazate), for control of twospotted spider mite (TSSM) (Tetranychus urticae Koch) in strawberries. In the greenhouse experiment, a combination treatment of P. persimilis and N. californicus was compared with single treatments of each species, Acramite application, and untreated control. All treatments significantly reduced TSSM numbers compared with the control. Field studies employed two approaches: one investigating the same five treatments as the greenhouse experiment and a second, comparing combination treatments of P. persimilis/N. californicus, Acramite/N. californicus, and Acramite/P. persimilis to single treatments of each and to control plots. Among the combination treatments, the P. persimilis/N. californicus treatment significantly reduced TSSM numbers compared with the control, but was not as effective as N. californicus alone during the 2003-2004 field season. Also, combination treatments of Acramite/N. californicus, and Acramite/P. persimilis significantly reduced TSSM populations compared with the control. These findings indicate that all three combination treatments are promising options for TSSM control in strawberries for growers in northern Florida and other strawberry producing areas of the world.

Zein Nanoparticles as Eco-Friendly Carrier Systems for Botanical Repellents Aiming Sustainable Agriculture.

Science.gov (United States)

Oliveira, Jhones L de; Campos, Estefânia V R; Pereira, Anderson E S; Pasquoto, Tatiane; Lima, Renata; Grillo, Renato; Andrade, Daniel Junior de; Santos, Fabiano Aparecido Dos; Fraceto, Leonardo Fernandes

2018-02-14

Botanical repellents represent one of the main ways of reducing the use of synthetic pesticides and the contamination of soil and hydric resources. However, the poor stability and rapid degradation of these compounds in the environment hinder their effective application in the field. Zein nanoparticles can be used as eco-friendly carrier systems to protect these substances against premature degradation, provide desirable release characteristics, and reduce toxicity in the environment and to humans. In this study, we describe the preparation and characterization of zein nanoparticles loaded with the main constituents of the essential oil of citronella (geraniol and R-citronellal). The phytotoxicity, cytotoxicity, and insect activity of the nanoparticles toward target and nontarget organisms were also evaluated. The botanical formulations showed high encapsulation efficiency (>90%) in the nanoparticles, good physicochemical stability, and effective protection of the repellents against UV degradation. Cytotoxicity and phytotoxicity assays showed that encapsulation of the botanical repellents decreased their toxicity. Repellent activity tests showed that nanoparticles containing the botanical repellents were highly repellent against the Tetranychus urticae Koch mite. This nanotechnological formulation offers a new option for the effective use of botanical repellents in agriculture, reducing toxicity, protecting against premature degradation, and providing effective pest control.

Development, oviposition, and mortality of Neoseiulus fallacis (Acari: Phytoseiidae) in response to reduced-risk insecticides.

Science.gov (United States)

Villanueva, Raul T; Walgenbach, James F

2005-12-01

Eight reduced-risk insecticides (acetamiprid, thiamethoxam, imidacloprid, thiacloprid, methoxyfenozide, pyriproxyfen, indoxacarb, and spinosad) and three conventional insecticides (azinphosmethyl, fenpropathrin, and esfenvalerate) were tested against Neoseiulus fallacis (Garman) (Acari: Phytoseiidae), the most abundant predacious mite in North Carolina apple (Malus spp.) orchards. To assess the effect of insecticides on development and mortality of N. fallacis immatures, 12-h-old eggs were individually placed on bean leaf disks previously dipped in insecticide solutions. Tetranychus urticae Koch (Acari: Tetranychidae) females were added as a food source. None of the reduced-risk insecticides significantly affected immature N. fallacis compared with the control; however, the pyrethroids esfenvalerate and fenpropathrin were highly toxic to immatures. To evaluate the effect of insecticides on mortality and oviposition of adult N. fallacis, 7- to 8-d-old females were confined on insecticide-treated bean leaves with Malephora crocea (Aizoaceae) pollen added as a food source. Spinosad resulted in the highest mortality, whereas azinphosmethyl, acetamiprid, fenpropathrin, and imidacloprid were moderately toxic, and mortality from esfenvalerate, indoxacarb, thiacloprid, methoxyfenozide, pyriproxyfen, and thiamethoxam did not differ significantly from the control. Oviposition was affected in a similar manner, with the exception of acetamiprid that did not affect oviposition, and thiamethoxam that reduced oviposition.

Mother-Offspring Relations: Prey Quality and Maternal Size Affect Egg Size of an Acariphagous Lady Beetle in Culture

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Eric W. Riddick

2012-01-01

Full Text Available We investigated mother-offspring relations in a lady beetle Stethorus punctillum Weise that utilizes spider mites as prey. Our objectives were to determine if (1 prey quality affects egg size, (2 maternal size correlates with egg size, and (3 egg size affects hatching success. We fed predators spider mites Tetranychus urticae Koch from lima bean Phaseolus lunatus L. foliage in the laboratory. Mothers of unknown body size offered high rather than low quality spider mites since birth produced larger eggs. Mothers of known body size offered only high quality spider mites, produced eggs of variable size, but mean egg size correlated positively with hind femur length. Mothers laid their eggs singly, rather than in batches, and eggs were large relative to femur size. Egg size did not affect hatch success; mean hatch rate exceeded 95% regardless of egg size. In conclusion, the quality of prey consumed by S. punctillum mothers while in the larval stage can affect their size as adults and, consequently, the size of their eggs. The behavior of laying eggs singly, the positive relationship between maternal size and mean egg size, and the high rate of egg hatch suggest that S. punctillum mothers invest heavily in offspring.

Predation-related odours reduce oviposition in a herbivorous mite.

Science.gov (United States)

Choh, Yasuyuki; Uefune, Masayoshi; Takabayashi, Junji

2010-01-01

When adult females of the herbivorous mite, Tetranychus urticae, were exposed to the predatory mite, Phytoseiulus persimilis, they laid fewer eggs than females that had not been exposed to P. persimilis when transferred onto a new leaf patch. However, when T. urticae females were exposed to either products of P. persimilis or artificially damaged conspecific eggs on a leaf patch, the number of T. urticae eggs on a new leaf patch did not differ significantly from the control. The reduced oviposition was neither due to the feeding activity on the leaf patch with P. persimilis nor to that on the new leaf patch. There was also no significant difference between the number of T. urticae eggs produced on a new leaf patch following exposure to the odours of a neighbouring leaf patch where there had previously been either P. persimilis or T. urticae adults. However, female T. urticae that had been exposed to odours from neighbouring leaf patches on which both T. urticae and P. persimilis had been placed produced significantly fewer eggs on a new leaf patch than those that had not been exposed to such odours. Neither odours from neighbouring intact leaf patches on which T. urticae eggs were preyed on by P. persimilis, nor odours from a neighbouring Parafilm patch on which T. urticae was preyed on by P. persimilis affected the oviposition of T. urticae. These data suggest that the presence of T. urticae, P. persimilis and a leaf patch are needed for the emission of odours to reduce oviposition in T. urticae.

Kurt Koch, Die Kirche Gottes : Gemeinschaft im Geheimnis des Glaubens

NARCIS (Netherlands)

Sarot, M.

2013-01-01

KURT KOCH ON THE CHURCH This article discusses Kurt Koch’s book on the church as a crucial text for con¬tem¬po¬ra¬ry theology. Koch adopts a ‘hermeneutics of reform’ and emphasizes that the image of the church as the people of God should not be employed in isolation from the image of the church as

The Timeless Legacy of Robert Koch

Indian Academy of Sciences (India)

Robert Koch was a German physician and scientist who made wide-ranging .... methods of bacterial staining so that bacteria could be visualized more easily and .... of whom became outstanding scientists in their own right, such as Friedrich.

Lamium album or urtica dioica?

African Journals Online (AJOL)

Proff.Adewunmi

Objectives: Diabetes mellitus, the most common endocrine disorder, is defined by hyperglycaemia. Urtica dioica or stinging nettle is known to have antidiabetic effects. Lamium album or non stinging nettle is shown to have some beneficial effects such as antioxidant, and cytoprotective properties. The purpose of this study ...

[Biologically active compounds from the aqueous extract of Urtica dioica].

Science.gov (United States)

Wagner, H; Willer, F; Kreher, B

1989-10-01

From the water extract of the roots of Urtica dioica (stinging nettle) a polysaccharide fraction was isolated which revealed activity in the carrageenan rat paw edema model and lymphocyte transformation test. Ion exchange chromatography and gel filtration of this fraction afforded 4 different polysaccharides, one of which reduced dose dependent hemolysis in the classical pathway of the complement test. The Urtica dioica lectin (UDA) was reisolated and found to stimulate the proliferation of human lymphocytes.

Identification of phytosterins in Urtica dioica L. (overground part

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G. P. Smoylovska

2017-02-01

Full Text Available Long since Urtica dioica L. was used in folk medicine as vitamin and hemostatic agents. Nowadays hypotensive, diuretic, antitumoral effects of medicines obtained from plant based raw materials from Urtica were experimentally proved. Pharmacologic activity is due to vitamins K1 and C, flavonoids, hydroxycinnamic acids, carbonic acids, polysaccharides containing in the leaves of plant. Using underground organs of plant as antineoplastic drugs is connected with phytosterins accumulation. Studying composition and assessment of phytosterins in overground part of plant is urgent now. The aim of research is to identify components and to assess phytosterins content in leaves and herb of Urtica dioica L. in Ukrainian flora. Materials and Methods. For chromato-mass spectrometry leaves and herb gathered in blossoming period have been used. The samples have been extracted with methylene chloride in presence of tridecane inner standard, and then the samples have been concentrated and submitted to chromatography on chromatograph Agilent Technology 6890N. The components have been identified using register for mass spectra NIST02 and WILEY2007 in combination with identification programs AMDIS and NIST. Results and Discussion. In both types of raw materials from Urtica dioica L. it has been revealed identical compounds related to olefins, higher aliphatic carbohydrates, phytosterins and so on. The total amount of biologically active substances extracted from the leaves is 529.76 mg/kg, from herbs it is 516.91 mg/kg. Untriacontane, nonocosane and trans-neophytadiene were predominant. Phytosterins stigmas-3,5,7-triene, campesterol, β-sitosterol presented in leaves 16.14 mg/kg, in herb they presented 15.42 mg/kg, that forms 3% approximately Conclusions. Composition and amount of phytosterins containing in leaves and herb of Urtica dioica L. study has been performed by chromate-mass-spectrometry. As a result three compounds of steroid nature have been identified

The Timeless Legacy of Robert Koch

Indian Academy of Sciences (India)

Home; Journals; Resonance – Journal of Science Education; Volume 11; Issue 9. The Timeless Legacy of Robert Koch - Founder of Medical Microbiology. Jaya S Tyagi. General Article Volume 11 Issue 9 September 2006 pp 20-28. Fulltext. Click here to view fulltext PDF. Permanent link:

Simultaneous realization of slow and fast acoustic waves using a fractal structure of Koch curve.

Science.gov (United States)

Ding, Jin; Fan, Li; Zhang, Shu-Yi; Zhang, Hui; Yu, Wei-Wei

2018-01-24

An acoustic metamaterial based on a fractal structure, the Koch curve, is designed to simultaneously realize slow and fast acoustic waves. Owing to the multiple transmitting paths in the structure resembling the Koch curve, the acoustic waves travelling along different paths interfere with each other. Therefore, slow waves are created on the basis of the resonance of a Koch-curve-shaped loop, and meanwhile, fast waves even with negative group velocities are obtained due to the destructive interference of two acoustic waves with opposite phases. Thus, the transmission of acoustic wave can be freely manipulated with the Koch-curve shaped structure.

SARS – Koch´Postulates proved.

Indian Academy of Sciences (India)

SARS – Koch´Postulates proved. Novel coronavirus identified from fluids of patients. Virus cultured in Vero cell line. Sera of patients have antibodies to virus. Cultured virus produces disease in Macaque monkeys. -produces specific immune response; -isolated virus is SARS CoV; -pathology similar to human.

Effects of Insecticides and Fungicides Commonly Used in Tomato Production on Phytoseiulus persimilis (Acari: Phtyoseiidae).

Science.gov (United States)

Ditillo, J L; Kennedy, G G; Walgenbach, J F

2016-12-01

The twospotted spider mite, Tetranychus urticae Koch (Acari: Tetranychidae), is an important pest of tomatoes in North Carolina. Resident populations of the predatory mite Phytoseiulus persimilis have recently been detected on field-grown tomatoes in central North Carolina, and potentially can be a useful biological control agent against T. urticae Laboratory bioassays were used to assess lethal and reproductive effects of 10 insecticides and five fungicides commonly used in commercial tomato production (chlorantraniliprole, spinetoram, permethrin, imidacloprid, dimethoate, dinotefuran, thiamethoxam, bifenthrin, fenpropathrin, lambda-cyhalothrin, azoxystrobin, chlorothalonil, boscalid, cyazofamid, and mancozeb) on P. persimilis adult females and eggs. Insecticides were tested using concentrations equivalent to 1×, 0.5×, and 0.1× of the recommended field rates. Fungicides were tested at the 1× rate only. Dimethoate strongly impacted P. persimilis with high adult mortality, reduced fecundity, and reduced hatch of eggs laid by treated adults, particularly at high concentrations. The pyrethroids lambda-cyhalothrin, bifenthrin, and fenpropathrin were associated with repellency and reproductive effects at high concentrations. Bifenthrin additionally caused increased mortality at high concentrations. Chlorantraniliprole, dinotefuran, and permethrin did not significantly affect mortality or reproduction. Imidacloprid significantly reduced fecundity and egg viability, but was not lethal to adult P. persimilis Thiamethoxam negatively impacted fecundity at the 1× rate. There were no negative effects associated with fungicide exposure with the exception of mancozeb, which impacted fecundity. Field trials were conducted to explore the in vivo impacts of screened insecticides on P. persimilis populations in the field. Field trials supported the incompatibility of dimethoate with P. persimilis populations. © The Authors 2016. Published by Oxford University Press on behalf

The Urtica dioica extract enhances sensitivity of paclitaxel drug to MDA-MB-468 breast cancer cells.

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Mohammadi, Ali; Mansoori, Behzad; Aghapour, Mahyar; Shirjang, Solmaz; Nami, Sanam; Baradaran, Behzad

2016-10-01

Due to the chemo resistant nature of cancer cells and adverse effects of current therapies, researchers are looking for the most efficient therapeutic approach which has the lowest side effects and the highest toxicity on cancer cells. The aim of the present study was to investigate the synergic effect of Urtica dioica extract in combination with paclitaxel on cell death and invasion of human breast cancer MDA-MB-468 cell line. To determine the cytotoxic effects of Urtica dioica extract with paclitaxel, MTT assay was performed. The scratch test was exploited to assess the effects of Urtica dioica, Paclitaxel alone and combination on migration of cancer cells. The expression levels of snail-1, ZEB1, ZEB2, twist, Cdc2, cyclin B1 and Wee1 genes were quantified using qRT-PCR and western blot performed for snail-1expression. The effects of plant extract, Paclitaxel alone and combination on different phases of cell cycle was analyzed using flow cytometry. Results of MTT assay showed that Urtica dioica significantly destroyed cancer cells. Interestingly, Concurrent use of Urtica dioica extract with paclitaxel resulted in decreased IC50 dose of paclitaxel. Moreover, findings of scratch assay exhibited the inhibitory effects of Urtica dioica, Paclitaxel alone and combination on migration of MDA-MB-468 cell line. Our findings also demonstrated that the extract substantially decreased the Snail-1 and related gene expression. Ultimately, Cell cycle arrest occurred at G2/M phase post-treatment by deregulating Cdc2 and wee1. Our results demonstrated that the dichloromethane extract of Urtica dioica inhibit cell growth and migration. Also, Urtica dioica extract substantially increased sensitivity of breast cancer cells to paclitaxel. Therefore, it can be used as a potential candidate for treatment of breast cancer with paclitaxel. Copyright © 2016 Elsevier Masson SAS. All rights reserved.

Practicum of applied radioactivity and radiochemistry by Herforth and Koch

International Nuclear Information System (INIS)

Herforth, L.; Huebner, K.

1989-01-01

The more-than-thirty-year history of a textbook of the application of radionuclides is described. In many countries the book has been proved useful for teaching specialists in the field of isotope technique. Above this it is accepted as a compendium for uses of radiophysical and radiochemical methods in science and industry. For 1991 a new, completely revised edition is planned entitled HERFORTH/KOCH Praktikum der angewandten Radioaktivitaet und Radiochemie (HERFORTH/KOCH Practicum of Applied Radioactivity and Radiochemistry). (author)

In Vitro Antimicrobial Activity of Iris pseudacorus and Urtica dioica

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Maryam Ramtin

2014-03-01

Full Text Available Background: In this study, the effects of antibacterial activity of Urtica dioica and Iris pseudacorus essential oils, native plant northern of Iran, were investigated for some selected bacteria. Material and Methods: The influence of essential oils was tested by the using of disk diffusion and micro-broth dilution methods against standard strains of the picked out bacteria. Gas Chromatography/Mass Spectroscopy (GC/MS analysis, bioactivity determination, Minimum inhibitory concentrations (MIC and minimum bactericidal concentration (MBC of essential oils were utilized for this goal. Results: This study showed that, Inhibition zone diameter varied from 11 to 19 mm and 9 to 17 mm for Urtica dioica and Iris pseudacorus respectively. In contrast, this figure fluctuated from 19 to 28 mm and 7 to 17 mm for gentamicin and ampicillin separately. By the application of micro-broth dilution technique, MICs for 1% essential oils were 1.8-7.5 μg/ml and 3.75-15 μg/ml for, Urtica dioica and Iris pseudacorus against gram-positive and gram-negative bacteria individually. Furthermore, the MBCs of herbal essences were 1.8-15 μg/ml for, Urtica dioica and 15-30 μg/ml for Iris. Conclusion: The application of essential oils for the bio-control of diseases, as a novel emerging alternative to antimicrobial treatments, lead to safer and more environmental management for infective diseases4T.4T

Leaf-morphology-assisted selection for resistance to two-spotted spider mite Tetranychus urticae Koch (Acari: Tetranychidae) in carnations (Dianthus caryophyllus L).

Science.gov (United States)

Seki, Kousuke

2016-10-01

The development of a cultivar resistant to the two-spotted spider mite has provided both ecological and economic benefits to the production of cut flowers. This study aimed to clarify the mechanism of resistance to mites using an inbred population of carnations. In the resistant and susceptible plants selected from an inbred population, a difference was recognised in the thickness of the abaxial palisade tissue by microscopic examination of the damaged leaf. Therefore, it was assumed that mites displayed feeding preferences within the internal leaf structure of the carnation leaf. The suitability of the host plant for mites was investigated using several cultivars selected using an index of the thickness from the abaxial leaf surface to the spongy tissue. The results suggested that the cultivar associated with a thicker abaxial tissue lowered the intrinsic rate of natural increase of the mites. The cultivars with a thicker abaxial tissue of over 120 µm showed slight damage in the field test. The ability of mites to feed on the spongy tissue during an early life stage from hatching to adult emergence was critical. It was possible to select a cultivar that is resistant to mites under a real cultivation environment by observing the internal structure of the leaf. © 2016 Society of Chemical Industry. © 2016 Society of Chemical Industry.

[GENETIC VARIABILITY OF MATERNAL PLANTS AND SEED EMBRYOS OF KOCH PINE POPULATIONS (PINUS KOCHIANA KLOTZSCH EX KOCH) IN CRIMEA].

Science.gov (United States)

Korshykov, I I; Kalafat, L O; Vynogradova, O M; Podgornyi, D Y

2016-01-01

Comparative studies of genetic variability were undertaken for 12 allozyme loci selections of trees and embryos of seed, and also for the crossing systems in five populations of Koch pine of (Pinus kochiana Klotzsch ex Koch) in Crimea. It was shown that in seed embryos the allelic variety peculiar to the maternal plants was restored, however the level of the available (H₀) heterozygosity was considerably lower, 0.286 and 0.189 respectively. For the embryos unlike the trees, in the majority of the analyzed loci the considerable divergence was specific in the actual distribution of genotypes from the theoretically expected according to Hardy- Weinberg law. The proportion of cross pollination at the unilocal (t(s)) estimation varied from 0.384 to 0.673 in the populations, while at the multilocal ones (t(m)) it was 0.639-0.841.

MODELLING OF THIN LAYER SOLAR DRYING KINETICS AND EFFECTIVE DIFFUSIVITY OF Urtica dioica LEAVES

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A. LAMHARRAR

2017-08-01

Full Text Available Urtica dioica is an endemic plant of Morocco used for its virtues in traditional medicine. The drying kinetics of Urtica dioica leaves in a convective solar dryer was studied. The kinetics of drying is studied for three temperatures (40, 50 and 60 °C, ambient air temperature ranged from 30 to 35 °C. The experimental results are used to determine the characteristic drying curve. Nine mathematical models have been used for the description of the drying curve. The Midilli-Kuck model was found to be the most suitable for describing the drying curves of Urtica dioica leaves. The drying parameters in this model were quantified as a function of the drying air temperature. Moisture transfer from Urtica dioica leaves was described by applying the Fick’s diffusion model. Effective moisture diffusivity of the product was in the range of 9.38 – 72.92×10-11 m2/s. A value of 88,49 kJ/mol was determined as activation energy.

Protective role of Urtica dioica L. (Urticaceae) extract on hepatocytes morphometric changes in STZ diabetic Wistar rats.

Science.gov (United States)

Golalipour, Mohammad Jafar; Ghafari, Soraya; Afshar, Mohammad

2010-09-01

The present investigation was carried out to evaluate the protective effect of the hydroalcoholic extract of Urtica dioica leaves on the quantitative morphometric changes in the liver of streptozotocin-induced diabetic rats. Thirty male Wistar rats were divided into control (G1), diabetic (G2), diabetic + Urtica dioica (G3) groups. The control group received only sham injections of intraperitoneal saline; the diabetic group received intraperitoneal saline for 5 days followed by streptozotocin (80 mg/kg) on the 6th day; and the diabetic + Urtica dioica group received 100 mg/kg Urtica dioica intraperitoneal (7) injections for 5 days and streptozotocin injection on the 6th day. After five weeks, the animals were sacrificed and whole livers removed. Liver specimens were used for quantitative morphometric analysis after hematoxylin and eosin staining. All data were statistically analyzed by one-way ANOVA and expressed as the mean with standard error of means. In the G3 (diabetic + Urtica diocia) group, the mean surface area of hepatocytes in the periportal zone (Z1) was greater than in G2 (diabetic) and G1 (control) groups, but this difference was not significant. No alteration was observed in the surface area of hepatocytes in the perivenous zone (Z3) in the diabetic + Urtica dioica (G3) group compared to the diabetic (G2) group. The mean nuclear area of hepatocytes of the rats in the diabetic + Urtica dioica (G3) group was higher in Z1 and lower in Z3 than that of rats in the diabetic (G2) group. The mean diameter of hepatocyte nuclei in the diabetic + Urtica dioica (G3) group was lower than that of diabetic (G2) and control (G1) groups in both Z1 and Z3. This study revealed that the administration of extract of Urtica dioica leaves before induction of diabetic with streptozotocin has a protective effect on the morphometric alterations of hepatocytes in the periportal and perivenous zones of the liver lobule in rats.

Urtica dioica extract attenuates depressive like behavior and associative memory dysfunction in dexamethasone induced diabetic mice.

Science.gov (United States)

Patel, Sita Sharan; Udayabanu, Malairaman

2014-03-01

Evidences suggest that glucocorticoids results in depression and is a risk factor for type 2 diabetes. Further diabetes induces oxidative stress and hippocampal dysfunction resulting in cognitive decline. Traditionally Urtica dioica has been used for diabetes mellitus and cognitive dysfunction. The present study investigated the effect of the hydroalcoholic extract of Urtica dioica leaves (50 and 100 mg/kg, p.o.) in dexamethasone (1 mg/kg, i.m.) induced diabetes and its associated complications such as depressive like behavior and cognitive dysfunction. We observed that mice administered with chronic dexamethasone resulted in hypercortisolemia, oxidative stress, depressive like behavior, cognitive impairment, hyperglycemia with reduced body weight, increased water intake and decreased hippocampal glucose transporter-4 (GLUT4) mRNA expression. Urtica dioica significantly reduced hyperglycemia, plasma corticosterone, oxidative stress and depressive like behavior as well as improved associative memory and hippocampal GLUT4 mRNA expression comparable to rosiglitazone (5 mg/kg, p.o.). Further, Urtica dioica insignificantly improved spatial memory and serum insulin. In conclusion, Urtica dioica reversed dexamethasone induced hyperglycemia and its associated complications such as depressive like behavior and cognitive dysfunction.

[Robert Koch was right. Towards a new interpretation of tuberculin therapy].

Science.gov (United States)

Cardona, Pere J

2006-01-01

At the centenary of Robert Koch's Nobel Prize award, tuberculosis treatment with tuberculin, which was announced in Berlin in 1890, is still considered a failure. Nevertheless, there is now sufficient information supporting the idea that tuberculin therapy was widely used until the second half of the twentieth century; thus, the impact of this treatment should be studied and related to the decrease in tuberculosis-related mortality recorded in that period. Moreover, tuberculin therapy has inspired at least two new immunotherapies; these, however, were directed toward precisely the opposite effect: suppression of the Koch phenomenon. Thus, inoculation of Mycobacterium vaccae polarizes the immune response towards the Th1 type; and inoculation of RUTI avoids local immunodepression after short-term chemotherapy without inducing toxicity. For this reason, Robert Koch's work on antituberculosis therapy should be reread and proper recognition given to his contribution in this field.

Plant architecture and prey distribution influence foraging behavior of the predatory mite Phytoseiulus persimilis (Acari: Phytoseiidae).

Science.gov (United States)

Gontijo, Lessando M; Nechols, James R; Margolies, David C; Cloyd, Raymond A

2012-01-01

The arrangement, number, and size of plant parts may influence predator foraging behavior, either directly, by altering the rate or pattern of predator movement, or, indirectly, by affecting the distribution and abundance of prey. We report on the effects of both plant architecture and prey distribution on foraging by the predatory mite, Phytoseiulus persimilis Athias-Henriot (Acari: Phytoseiidae), on cucumber (Cucumis sativus L.). Plants differed in leaf number (2- or 6-leafed), and there were associated differences in leaf size, plant height, and relative proportions of plant parts; but all had the same total surface area. The prey, the twospotted spider mite Tetranychus urticae Koch (Acari: Tetranychidae), were distributed either on the basal leaf or on all leaves. The effect of plant architecture on predator foraging behavior varied depending on prey distribution. The dimensions of individual plant parts affected time allocated to moving and feeding, but they did not appear to influence the frequency with which predators moved among different plant parts. Overall, P. persimilis moved less, and fed upon prey longer, on 6-leafed plants with prey on all leaves than on plants representing other treatment combinations. Our findings suggest that both plant architecture and pattern of prey distribution should be considered, along with other factors such as herbivore-induced plant volatiles, in augmentative biological control programs.

Effects of Urtica dioica on hepatic ischemia‐reperfusion injury in rats

Science.gov (United States)

Kandis, Hayati; Karapolat, Sami; Yildirim, Umran; Saritas, Ayhan; Gezer, Suat; Memisogullari, Ramazan

2010-01-01

OBJECTIVES: To evaluate the effects of Urtica dioica on hepatic ischemia‐reperfusion injury. METHODS: Thirty adult male Wistar albino rats were divided into three groups: sham group (group 1), control group (group 2), and Urtica dioica group (group 3). All the rats were exposed to hepatic ischemia for 60 min, followed by 60 min of reperfusion. In group 2, a total of 2 ml/kg 0.9% saline solution was given intraperitoneally. In group 3, a total of 2 ml/kg Urtica dioica was given intraperitoneally. At the end of the procedure, liver tissue and blood samples were taken from all rats. Serum aspartate aminotransferase, alanine aminotransferase, lactate dehydrogenase, ceruloplasmin, catalase, paraoxonase, arylesterase, and lipid hydroperoxide levels were measured. Liver tissue histopathologies were also evaluated by light microscopy. RESULTS: Serum aspartate aminotransferase, alanine aminotransferase and lactate dehydrogenase levels were significantly higher in group 2 than in group 1, and significantly lower in group 3 than in group 2. Also, group 2 had higher serum lipid hydroperoxides and ceruloplasmin levels but lower catalase, paraoxonase, and arylesterase levels than group 1. In group 3, serum lipid hydroperoxides and ceruloplasmin levels were significantly lower, and catalase, paraoxonase, and arylesterase levels were higher than those in group 2. Histopathological examination showed that liver tissue damage was significantly decreased in group 3 compared with group 2. CONCLUSIONS: Urtica dioica has a protective effect on the liver in hepatic ischemia‐reperfusion‐injured rats. PMID:21340227

Effects of Urtica dioica on hepatic ischemia-reperfusion injury in rats.

Science.gov (United States)

Kandis, Hayati; Karapolat, Sami; Yildirim, Umran; Saritas, Ayhan; Gezer, Suat; Memisogullari, Ramazan

2010-01-01

To evaluate the effects of Urtica dioica on hepatic ischemia-reperfusion injury. Thirty adult male Wistar albino rats were divided into three groups: sham group (group 1), control group (group 2), and Urtica dioica group (group 3). All the rats were exposed to hepatic ischemia for 60 min, followed by 60 min of reperfusion. In group 2, a total of 2 ml/kg 0.9% saline solution was given intraperitoneally. In group 3, a total of 2 ml/kg Urtica dioica was given intraperitoneally. At the end of the procedure, liver tissue and blood samples were taken from all rats. Serum aspartate aminotransferase, alanine aminotransferase, lactate dehydrogenase, ceruloplasmin, catalase, paraoxonase, arylesterase, and lipid hydroperoxide levels were measured. Liver tissue histopathologies were also evaluated by light microscopy. Serum aspartate aminotransferase, alanine aminotransferase and lactate dehydrogenase levels were significantly higher in group 2 than in group 1, and significantly lower in group 3 than in group 2. Also, group 2 had higher serum lipid hydroperoxides and ceruloplasmin levels but lower catalase, paraoxonase, and arylesterase levels than group 1. In group 3, serum lipid hydroperoxides and ceruloplasmin levels were significantly lower, and catalase, paraoxonase, and arylesterase levels were higher than those in group 2. Histopathological examination showed that liver tissue damage was significantly decreased in group 3 compared with group 2. Urtica dioica has a protective effect on the liver in hepatic ischemia-reperfusion-injured rats.

Pharmacological and toxicological evaluation of Urtica dioica.

Science.gov (United States)

Dar, Sabzar Ahmad; Ganai, Farooq Ahmad; Yousuf, Abdul Rehman; Balkhi, Masood-Ul-Hassan; Bhat, Towseef Mohsin; Sharma, Poonam

2013-02-01

Medicinal plants are a largely unexplored source of drug repository. Urtica dioica L. (Urticaceae) is used in traditional medicine to treat diverse conditions. The present study describes the antidiabetic, antiinflammatory, antibacterial activity, and toxicological studies of Urtica dioica. U. dioica leaves were subjected to solvent extraction with hexane, chloroform, ethyl acetate, methanol, and aqueous, respectively, and screened for antidiabetic (300 mg/kg bw by glucose tolerance test; GTT), antiinflammatory (200 mg/kg bw by rat paw edema assay) and antibacterial activities [by disc-diffusion and minimum inhibitory concentration (MIC) assays]. Toxicological studies were carried on Artemia salina and Wistar rats; phytochemical analyses were carried out, using chromatographic and spectroscopic techniques. The aqueous extract of U. dioica (AEUD) significantly (p 1000 μg/mL each on A. salina. Our results showed that the U. dioica leaves are an interesting source of bioactive compounds, justifying their use in folk medicine, to treat various diseases.

Effects of Euseius stipulatus on establishment and efficacy in spider mite suppression of Neoseiulus californicus and Phytoseiulus persimilis in clementine.

Science.gov (United States)

Abad-Moyano, Raquel; Urbaneja, Alberto; Hoffmann, Daniela; Schausberger, Peter

2010-04-01

The two-spotted spider mite, Tetranychus urticae, is one of the most problematic phytophagous pests in Spanish clementine orchards. The most abundant predatory mites in this ecosystem are Euseius stipulatus, Phytoseiulus persimilis and Neoseiulus californicus. Euseius stipulatus is dominant but poorly adapted to utilize T. urticae as prey. It mainly persists on pollen and citrus red mite, Panonychus citri. A recent study suggested that the more efficacious T. urticae predators P. persimilis and N. californicus are negatively affected by lethal and non-lethal intraguild interactions with E. stipulatus. Here, we investigated the potential of N. californicus and P. persimilis to colonize and thrive on young clementine trees infested by T. urticae in presence and absence of E. stipulatus. Presence of E. stipulatus interfered with establishment and abundance of P. persimilis and negatively affected the efficacy of N. californicus in T. urticae suppression. In contrast, the abundance of E. stipulatus was not affected by introduction of a second predator. Trait-mediated effects of E. stipulatus changing P. persimilis and N. californicus behavior and/or life history were the most likely explanations for these outcomes. We conclude that superiority of E. stipulatus in intraguild interactions may indeed contribute to the currently observed predator species composition and abundance, rendering natural control of T. urticae in Spanish clementine orchards unsatisfactory. Nonetheless, stronger reduction of T. urticae and/or plant damage in the predator combination treatments as compared to E. stipulatus alone indicates the possibility to improve T. urticae control via repeated releases of N. californicus and/or P. persimilis.

Confirming the appearance of excess success: Reply to van Boxtel and Koch (2016).

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Francis, Gregory

2016-12-01

van Boxtel and Koch (Psychonomic Bulletin & Review. doi: 10.3758/s13423-016-1010-0 , 2016) reported finding problems in the Test for Excess Success (TES) analysis in Francis (Psychonomic Bulletin & Review, 21, 1180-1187, 2014). They argued that their findings undermined the general analysis and the conclusions of the specific TES analysis for their article (van Boxtel & Koch in Psychological Science, 23(4), 410-418, 2012). As shown in this paper, their reported problems reflect misunderstandings about both the general properties of a TES analysis and how it was applied to their specific set of findings. Another look at the findings and theoretical claims in van Boxtel and Koch (Psychological Science, 23(4), 410-418, 2012) confirms the appearance of excess success.

Das Fortbildungsangebot der Bibliothek des Robert Koch-Instituts: Dienstleistung im Publikationsprozess

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Senst, Henriette

2013-12-01

Full Text Available [english] Robert Koch-Institute’s scientists are supported during the publishing process in different ways. Relating to frequently asked questions the library offers trainings, which are integrated in the training program of the institute.How does a good literature research work? How do I manage my literature and how do I cite correctly? What do I have to consider during the publishing process? These and other questions are answered in trainings on literature research, managing bibliographies with EndNote and “Scientific Publishing in the Robert Koch-Institute” which take place regularly.

[Stinging nettle (Urtica dioica L.)--botanical characteristics, biochemical composition and health benefits].

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Jakubczyk, Karolina; Janda, Katarzyna; Szkyrpan, Sylwia; Gutowska, Izabela; Wolska, Jolanta

2015-01-01

Stinging nettle (Urtica dioica L.) belongs to the family Urticaceae. It grows in the wild form in Asia, Europe, North America and North Africa. Stinging nettle is also a widespread ruderal plant found in Poland. Urtica dioica L., as a plant rich in biologically active compounds, is considered one of the most important plants used in phytotherapy. In vitro and in vivo studies have demonstrated its antioxidant, antiplatelet, hypoglycaemic and hypocholesterolemic properties. Research conducted in recent years indicates the possibility of using nettle in chemoprevention, diabetes, benign prostatic hyperplasia and urologic diseases.

[The influence of stinging nettle (Urtica dioica L.) extracts on the activity of catalase in THP1 monocytes/macrophages].

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Wolska, Jolanta; Janda, Katarzyna; Szkyrpan, Sylwia; Gutowska, Izabela

2015-01-01

Stinging nettle (Urtica dioicd L.) is one of the most valuable plants used in phytotherapy. The herbal raw material is a herb (Urticae herba), leaves (Urticae folium), roots (Urticae radix) and seeds (Urticae semina). This plant is a good source of vitamins, minerals, fibre, protein and biologically active compounds with antioxidant properties. The literature provides limited information about the chemical composition and properties of the seed heads. No papers are available on the effect of extracts of this plant on catalase activity in human cells. The aim of this study was to investigate the impact of stinging nettle (Urtica dioica L.) extracts on the antioxidant activity of catalase in THP1 macrophages. Two types of extracts: water and alcohol, at two different concentrations, were used in experiments. Nettle was collected in September and October in 2012 in the area of Szczecin. The collected plant material was frozen and lyophilized. After those procedures water and alcohol extracts of nettle were prepared and then added to THP1 cells. The antioxidant activity of catalase was established with the spectrophotometric method. The study showed that both extracts (water and alcohol) significantly increased the antioxidant activity of catalase in THP1 cells. The increase in catalase was directly proportional to the concentration of the added alcohol extract.

Self-Similarity of Plasmon Edge Modes on Koch Fractal Antennas.

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Bellido, Edson P; Bernasconi, Gabriel D; Rossouw, David; Butet, Jérémy; Martin, Olivier J F; Botton, Gianluigi A

2017-11-28

We investigate the plasmonic behavior of Koch snowflake fractal geometries and their possible application as broadband optical antennas. Lithographically defined planar silver Koch fractal antennas were fabricated and characterized with high spatial and spectral resolution using electron energy loss spectroscopy. The experimental data are supported by numerical calculations carried out with a surface integral equation method. Multiple surface plasmon edge modes supported by the fractal structures have been imaged and analyzed. Furthermore, by isolating and reproducing self-similar features in long silver strip antennas, the edge modes present in the Koch snowflake fractals are identified. We demonstrate that the fractal response can be obtained by the sum of basic self-similar segments called characteristic edge units. Interestingly, the plasmon edge modes follow a fractal-scaling rule that depends on these self-similar segments formed in the structure after a fractal iteration. As the size of a fractal structure is reduced, coupling of the modes in the characteristic edge units becomes relevant, and the symmetry of the fractal affects the formation of hybrid modes. This analysis can be utilized not only to understand the edge modes in other planar structures but also in the design and fabrication of fractal structures for nanophotonic applications.

Search for the antiprostatic principle of stinging nettle (Urtica dioica) roots.

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Wagner, H; Willer, F; Samtleben, R; Boos, G

1994-12-01

While searching for the antiprostatic active principle of the roots of Urtica dioica we ethanol-precipitated a polysaccharide mixture from an aqueous root extract and obtained chemically defined acidic polysaccharides with molecular masses of 15-210kDa. The chemical structures of these compounds have been determined. Some polysaccharides stimulated T lymphocytes in vitro while others influenced the complement system or triggered the release of TNF-α. The crude polysaccharide extract showed a prolonged antiinflammatory activity in the rat paw edema test for 22 hr, which is comparable to the pharmacological efficacy of indometacin. We have reisolated the isolectin mixture (UDA) originally detected in Urtica roots by Peumans et al. (1984). This mixture displayed immunomodulatory effects on T lymphocytes in a dose-dependent manner. In addition, UDA also directly inhibited cell proliferation and blocked binding of epidermal growth factor to its receptor on a tumor cell line, as determined by a [(125)I]-EGF binding assay. These investigations suggest that Urtica polysaccharides and also the N-acetyl-glucosamine specific lectin UDA play a major role in the antiprostatic activity of the drug and phytopreparations containing it. Copyright © 1994 Gustav Fischer Verlag, Stuttgart · Jena · New York. Published by Elsevier GmbH.. All rights reserved.

Incidence of pests and viral disease on pepino (Solanum muricatum Ait.) in Kanagawa Prefecture, Japan.

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Kim, Ok-Kyung; Ishikawa, Tadashi; Yamada, Yoshihiro; Sato, Takuma; Shinohara, Hirosuke; Takahata, Ken

2017-01-01

The solanaceous fruit crop pepino ( Solanum muricatum Ait.), originating in the Andes, is grown commercially in South American countries and New Zealand. In these areas, pests and diseases of pepino have been identified well; however, to date, these have seldom been investigated in detail in Japan. Herein, we attempt to reconstruct an agricultural production system for commercial pepino crops in Japan, and evaluate the incidence of pests and viral diseases on pepino. The findings of this study will facilitate in developing a better crop system for the commercial cultivation of healthy pepino fruits. A total of 11 species, comprising nine insects and two mites, were recognized as pests of pepino plants in our experimental fields in Kanagawa Prefecture, central Honshu, Japan. Of these pest species, the two-spotted spider mite Tetranychus urticae Koch, 1836 and the cotton aphid Aphis gossypii Glover, 1877, were remarkably abundant than the other pest species. Eventually, 13 species, including two previously recorded, are currently recognized as the pests of pepino in Japan. With regard to viruses, we tested two species Alfalfa mosaic virus (AMV) and Cucumber mosaic virus (CMV), as well as three genera Carlavirus , Potexvirus , and Potyvirus . No virus was detected in symptomatic pepino leaves collected in our experimental fields. This is a first report on the identification of pests on pepino plants in Kanagawa Prefecture, Japan and elucidates the relationship between currently occurring pests of pepino plants and potential viral pathogens that they can transmit.

Diurnal temperature variations affect development of a herbivorous arthropod pest and its predators.

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Dominiek Vangansbeke

Full Text Available The impact of daily temperature variations on arthropod life history remains woefully understudied compared to the large body of research that has been carried out on the effects of constant temperatures. However, diurnal varying temperature regimes more commonly represent the environment in which most organisms thrive. Such varying temperature regimes have been demonstrated to substantially affect development and reproduction of ectothermic organisms, generally in accordance with Jensen's inequality. In the present study we evaluated the impact of temperature alternations at 4 amplitudes (DTR0, +5, +10 and +15°C on the developmental rate of the predatory mites Phytoseiulus persimilis Athias-Henriot and Neoseiulus californicus McGregor (Acari: Phytoseiidae and their natural prey, the two-spotted spider mite Tetranychus urticae Koch (Acari: Tetranychidae. We have modelled their developmental rates as a function of temperature using both linear and nonlinear models. Diurnally alternating temperatures resulted in a faster development in the lower temperature range as compared to their corresponding mean constant temperatures, whereas the opposite was observed in the higher temperature range. Our results indicate that Jensen's inequality does not suffice to fully explain the differences in developmental rates at constant and alternating temperatures, suggesting additional physiological responses play a role. It is concluded that diurnal temperature range should not be ignored and should be incorporated in predictive models on the phenology of arthropod pests and their natural enemies and their performance in biological control programmes.

Diurnal Temperature Variations Affect Development of a Herbivorous Arthropod Pest and its Predators

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Vangansbeke, Dominiek; Audenaert, Joachim; Nguyen, Duc Tung; Verhoeven, Ruth; Gobin, Bruno; Tirry, Luc; De Clercq, Patrick

2015-01-01

The impact of daily temperature variations on arthropod life history remains woefully understudied compared to the large body of research that has been carried out on the effects of constant temperatures. However, diurnal varying temperature regimes more commonly represent the environment in which most organisms thrive. Such varying temperature regimes have been demonstrated to substantially affect development and reproduction of ectothermic organisms, generally in accordance with Jensen’s inequality. In the present study we evaluated the impact of temperature alternations at 4 amplitudes (DTR0, +5, +10 and +15°C) on the developmental rate of the predatory mites Phytoseiulus persimilis Athias-Henriot and Neoseiulus californicus McGregor (Acari: Phytoseiidae) and their natural prey, the two-spotted spider mite Tetranychus urticae Koch (Acari: Tetranychidae). We have modelled their developmental rates as a function of temperature using both linear and nonlinear models. Diurnally alternating temperatures resulted in a faster development in the lower temperature range as compared to their corresponding mean constant temperatures, whereas the opposite was observed in the higher temperature range. Our results indicate that Jensen’s inequality does not suffice to fully explain the differences in developmental rates at constant and alternating temperatures, suggesting additional physiological responses play a role. It is concluded that diurnal temperature range should not be ignored and should be incorporated in predictive models on the phenology of arthropod pests and their natural enemies and their performance in biological control programmes. PMID:25874697

Comparative studies on uptake and translocation of labelled dimethoate and methamidophos by means of systemic and local bibitors

International Nuclear Information System (INIS)

Richter, S.; Dedek, W.

1983-01-01

Uptake, mobility and translocation of 14 C-dimethoate and 32 P-methamidophos in Vicia faba L. and Oryza sativa L. were studied by means of pea aphid (Acyrthosiphon pisum Harris), red spider mite (Tetranychus urticae Koch) and rice cicada (Sogatodes orizicola Muir). A relationship was found to exist between the uptake of active ingredients and the individual developmental stages. Both ingredients are rapidly taken up through the roots and translocated throughout the plant, the rate of incorporation being higher with mites - due to the higher share of active ingredients in their cells - than with aphids. Tests without allowing time for exposition are possible and provide direct information on the rate of uptake. Both dimethoate and methamidophos penetrate into the leaf tissue. The phloem is loaded somewhat more slowly, the rate of load being more favourable with dimethoate. Acropetal and basipetal translocation proceed accordingly. However, the two active ingredients under review are not transported in insecticidal or acaricidal concentrations. Unlike dimethoate, the insecticidal action of methamidophos in field bean persists for 20 days or more. Studies on the mobility of dimethoate in rice plants point to a high apoplastic translocation in the treated leaf and to a somewhat retarded acropetal translocation in insecticidal concentrations. These results show that bioassays may be carried out not only with aphids but also with spider mites and cicades to demonstrate the mobility of chemical agents in plants. (author)

Urtica dioica Induces Cytotoxicity in Human Prostate Carcinoma ...

African Journals Online (AJOL)

Purpose: To evaluate the cytotoxic mechanisms of an extract from the leaves of the Urtica dioica (UD) plant in LNCaP prostate cancer cells. Methods: LNCaP cells were exposed to the UD extract for 24hrs and cell viability assessed using the MTT assay. Reactive oxygen species generation was assessed using the NBT ...

THE PROSPECTS OF THE USE OF DRUGS BASED ON RHIZOMES AND ROOTS OF URTICA DIOICA L.

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E. A. Balagozyan

2015-01-01

Full Text Available Stinging nettle (Urtica dioica L. from the Urticaceae family is one of the popular medicinal plants. The leaves of Urtica doica L. are used in our country as a hemostatic agent. The rhizomes and roots are the base for the drugs for prostatic adenoma treatment in foreign countries. Earlier we studied acute toxicity, and diuretic activity of an extract of the rootstock with roots of Urtica doica L. We have conducted a study of antimicrobial activity of water and alcohol-water extracts from the rhizomes and roots of Urtica dioica L. The determination of a minimal inhibiting concentration was conducted by using a method of double series broth dilution. Bacillus cereus, Candida albicans, Escherichia coli, Pseudomonas aeruginosa, Staphylococcus aureus microorganisms were used as testing cultures. The study showed that the broth and liquid extract of the nettle, obtained on the basis of 70% ethanol do not stop the growth of microorganisms. The liquid nettle extract obtained by 40% ethanol is characterized by the weak antimicrobial activity.

Protective Effect of Urtica dioica on Liver Injury Induced By Hepatic Ischemia Reperfusion Injury in Rats

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Alpaslan TERZİ

2010-05-01

Full Text Available Background: This study was designed to investigate the effects of Urtica dioica on liverischemia reperfusion injury in rats. Methods: Thirty male Wistar-albino rats were used in this experimental study. Animals weredivided into three groups as sham operated (group 1, control (group 2, and Urtica dioicatreatment group (group 3. Urtica dioica 2ml/kg were administered intraperitoneally beforeischemia and immediately after the reperfusion. The levels of total antioxidant capacity, totalfree sulfidril group, Total oxidant status, Oxidative stress index, and myeloperoxidase in livertissues were measured. The serum levels of ALT, AST and LDH were also measuredResults: Total antioxidant capacity and total free sulfidril group in liver tissue were significantlyhigher in group 3 than in group 2. Oxidative stress index and myeloperoxidase in liver tissuewere significantly lower in group 3 than the group 2. The levels of liver enzymes in treatmentgroup were significantly lower than those in the control group. Histological tissue damage wasmilder in the treatment group than that in the control group.Conclusion: It is concluded that Urtica dioica increase the antioxidant capacity and decreaseoxidative stress and liver enzymes in the hepatic ischemi reperfusion injury of rats.

Pulling the sting out of nettle systematics - A comprehensive phylogeny of the genus Urtica L. (Urticaceae).

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Grosse-Veldmann, Bernadette; Nürk, Nicolai M; Smissen, Rob; Breitwieser, Ilse; Quandt, Dietmar; Weigend, Maximilian

2016-09-01

The genus Urtica L. is subcosmopolitan, found on all continents (except Antarctica) and most extratropical islands and ranges from Alaska to Patagonia, Spitzbergen to the Cape and Camtschatka to the subantarctic islands. However, throughout its geographical range morphologically nearly indistinguishable species are found alongside morphologically quite disparate species, with the overall diversity of morphological characters extremely limited. The systematics of Urtica have puzzled scientists for the past 200years and no single comprehensive attempt at understanding infrageneric relationships has been published in the past, nor are species delimitations unequivocally established. We here provide the first comprehensive phylogeny of the genus including 61 of the 63 species recognized, represented by 144 ingroup accessions and 14 outgroup taxa. The markers ITS1-5.8S-ITS2, psbA-trnH intergenic spacer, trnL-trnF and trnS-trnG are used. The phylogeny is well resolved. The eastern Asian Zhengyia shennongensis T. Deng, D.G. Zhang & H. Sun is retrieved as sister to Urtica. Within Urtica, a clade comprising the western Eurasian species U. pilulifera L. and U. neubaueri Chrtek is sister to all other species of the genus. The phylogenetic analyses retrieve numerous well-supported clades, suggesting previously unsuspected relationships and implying that classically used taxonomic characters such as leaf morphology and growth habit are highly homoplasious. Species delimitation is problematical, and several accessions assigned to Urtica dioica L. (as subspecies) are retrieved in widely different places in the phylogeny. The genus seems to have undergone numerous dispersal-establishment events both between continents and onto different islands. Three recent species radiations are inferred, one in America centered in the Andes, one in New Zealand, and one in northern Eurasia which includes Urtica dioica s.str. sensu Henning et al. (2014). The present study provides the basis of a

[Robert Koch, eminent medical bacteriologist, creator of the applied microbiology and its technnology].

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Suárez Fernández, Guillermo

2012-01-01

In our communication we wish consider to bring at a first instance the egregious figure of Robert Koch a hundred of years after his dead. Nobody else had contributed so much in the development of the bacteriology as unic and independent science. Several books and biographical sketchs had been published about Koch in german, english and french, mainly, with differents detais and interpretations, about his life. However, nobody doubred about his innovator spirit and scientist at highest level. This communication revise and discuss diverse chapters about his life as innovator, researcher, groups leader and Magister.

Antimicrobial activity of methanolic extracts of Sambucus ebulus and Urtica dioica against clinical isolates of methicillin resistant Staphylococcus aureus.

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Salehzadeh, Ali; Asadpour, Leila; Naeemi, Akram Sadat; Houshmand, Elham

2014-01-01

Increase in the emergence of drug -resistant pathogens led to the development of natural antimicrobials. In this study the antimicrobial effect of methanolic extracts of Sambucus ebulus and Urtica dioica on 16 skin and wound infections isolates of methicillin resistant S. aureus have been studied. Solvent extraction procedure was done using soxhlet apparatus for extracting antimicrobial agents from freeze dried plants. Antibacterial activity was measured using agar well diffusion method. The MIC of Sambucus ebulus and Urtica dioica extracts against the standard strain of S. aureus ATCC 6538 were determined using the micro dilution method at 15 mg and 20 mg respectively. All the test bacteria were found sensitive to the Sambucus ebulus extract and only one isolate was resistant to Urtica dioica extract. Extracts of Sambucus ebulus and Urtica dioica possess antibacterial potency against MRSA isolates and may be used as a natural antiseptics and antimicrobial agents in medicine.

Sex ratio variation and sex determination in Urtica dioica

NARCIS (Netherlands)

Glawe, Grit Anja

2006-01-01

This thesis will first document on variation in progeny sex ratios among individual female plants of Urtica dioica at our field site in Meijendel (Chapter 2). Next, we show that there is also considerable sex ratio variation among male and female flowering shoots in 26 natural populations studied

Effect of Urtica dioica Leaf Alcoholic and Aqueous Extracts on the Number and the Diameter of the Islets in Diabetic Rats.

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Qujeq, Durdi; Tatar, Mohsen; Feizi, Farideh; Parsian, Hadi; Sohan Faraji, Alieh; Halalkhor, Sohrab

2013-01-01

Urtica dioica has been known as a plant that decreases blood glucose. Despite the importance of this plant in herbal medicine, relatively little research has been down on effects of this plant on islets yet. The objective of the current study was to evaluate the effect of dried Urtica dioica leaf alcoholic and aqueous extracts on the number and the diameter of the islets and histological parameters in streptozocin-induced diabetic rats. Six rats were used in each group. Group I: Normal rats were administered saline daily for 8 weeks. Group II: Diabetic rats were administered streptozotocin, 50 mg/kg of body weight; Group III: Diabetic rats were administered dried Urtica dioica leaf aqueous extracts for 8 weeks; Group IV: Diabetic rats were administered dried Urtica dioica leaf alcoholic extracts for 8 weeks. The animals, groups of diabetic and normal, were sacrificed by ether anaesthesia. Whole pancreas was dissected. The tissue samples were formalin fixed and paraffin embedded for microscopic examination. Histologic examination and grading were carried out on hematoxylin-eosin stained sections. The effects of administration of dried Urtica dioica leaf alcoholic and aqueous extracts to diabetic rats were determined by histopathologic examination. The pancreas from control rats showed normal pancreatic islets histoarchitecture. Our results also, indicate that the pancreas from diabetic rats show injury of pancreas tissue while the pancreas from diabetic rats treated with dried Urtica dioica leaf alcoholic and aqueous extracts show slight to moderate rearrangement of islets. According to our findings, dried Urtica dioica leaf alcoholic and aqueous extracts can cause a suitable repair of pancreatic tissue in streptozocin-induced diabetic experimental model.

Assessment of Antidermatophytic Activities of Urtica dioica L against ...

African Journals Online (AJOL)

Purpose: To investigate the antidermatophytic effects of Urtica dioica L. against Microsporum canis in vitro and in a guinea pig model. Methods: The in vitro antifungal activity of the extracts was measured by disc diffusion method and assessment of minimum inhibitory concentration (MIC). The dorsum of the guinea pigs was ...

Objects, pictures and sounds: the ethnography of Theodor Koch-Grünberg (1872-1924

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Erwin Frank

2010-04-01

Full Text Available The article characterizes the ethnological theory and method of Theodor Koch-Grünberg (1872-1924, a German anthropologist who made four visits to Brazil between 1896 and 1924, and who was especially noted for his writings about the Indians of the Rio Negro and Rio Branco, and the ethnographic collections, sound recordings, photography and films made during these journeys. The author relates this documentary material with Koch-Grünberg’s ethnographic project within the tradition of German Völkerkunde.

The effects of Urtica dioica L. leaf extract on aniline 4-hydroxylase in mice.

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Ozen, Tevfik; Korkmaz, Halil

2009-01-01

The effects of hydroalcoholic (80% ethanol-20% water) extract of Urtica dioica L. on microsomal aniline 4-hydroxylase (A4H) were investigated in the liver of Swiss albino mice (8- 10-weeks-old) treated with two doses (50 and 100 mg/kg body weight, given orally for 14 days ). The activities of A4H showed a significant increase in the liver at both dose levels of extract treatment. The hydroalcoholic extract of Urtica dioica induced the activities of A4H that had been increased by treatment of metal ions (Mg2+ and Ca2+) and the mixture of cofactors (NADH and NADPH). At saturated concentration of cofactor, microsomal A4H exhibited significantly even higher activities in the presence of the mixture of cofactors than NADPH and NADH. Mg2+ and Ca2+ ions acted as stimulants in vitro. The present results suggest that the hydroalcoholic extract of Urtica dioica may have modalatory effect on aniline hydroxylase at least in part and enhance the activity of A4H adding metals ions and cofactors.

Urtica dioica attenuate effect of Doxorobicin‐Induced changes on sperm parameters in the mice

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Zahra Baninameh

2016-11-01

Full Text Available Doxorubicin (DXR is used as an antitumor agent for the treatment of human neoplasm. The use of DXR has adverse effect on reproductive system including testicular toxicity and alteration in semen quality. The aim of this study was to evaluate the protective effects of Urtica dioica against Doxorobicin‐Induced changes on sperm parameters. 24 male mice were randomly divided into 4 groups. Control group received normal saline solution throughout the course of the study. Urtica dioica (UD control group, received UD (100 mg/kg body weight thrice in a week and DOX (3 mg/kg body weight once in a week injected intraperitoneally in Doxorubicin (DXR control group and Urtica dioica- Doxorubicin (UD-DXR group, received Urtica dioica (100 mg/kg body weight three times in a week and DOX (3 mg/kg body weight once in a week through the route for a period of 2 weeks. At the end of experimental period, all animal were sacrificed by cervical dislocation, their epididymes were removed and sperm analysis were done. In mice with DXR administration, epididymal sperm motility, progressive motility, sperm count and viability significantly decrease while sperm cells with abnormal morphology significantly increase when compared with control groups. Co-treatment with UD attenuate toxicity effect of DXR and improve sperm parameters. Results of our study showed that UD diminished DXR-induced testicular toxicity and improve semen parameters, thus suggesting its co-administration as a protective agent during doxorubicin treatment. Further studies should be aimed to determine protective effect of UD against chemotherapeutic agents such as DXR.

DETERMINATION ON THE AGRICULTURAL AND QUALITY PROPERTIES OF URTICA PILULIFERA L. (ISIRGAN) UNDER BORNOVA ECOLOGICAL CONDITIONS

OpenAIRE

Sancaktaroğlu, Sezgin; Bayram, Emine

2011-01-01

Five species of nettle (Urtica sp.) are found in Turkey. Stinging Nettle (Urtica pilulifera L.), is naturally distributed in the temperate zone of the world. It contains proteins, flavonoids, fatty acids, vitamins and minerals. So, its leaves, roots and seeds are used for food, fiber, herbal medicine, colour agent and cosmetic industry. U. pilulifera is an annual plant and its seeds are locally called ‘'black nettle seed''. The species hasn't been cultivated yet in agriculture. The aim ...

Resistance source to cowpea aphid (Aphis craccivora Koch) in ...

African Journals Online (AJOL)

STORAGESEVER

2008-07-18

Jul 18, 2008 ... The present study evaluated the resistance of 7 varieties of the broad bean Vicia faba L. to cowpea aphid, Aphis craccivora Koch, 1854. These landraces from the region of Biskra (in the south of Algeria) were selected in an initial field trial and subjected to further testing in the greenhouse. Landrace V51.

Lamium album or Urtica dioica? Which is more effective in ...

African Journals Online (AJOL)

Objectives: Diabetes mellitus, the most common endocrine disorder, is defined by hyperglycaemia. Urtica dioica or stinging nettle is known to have antidiabetic effects. Lamium album or non stinging nettle is shown to have some beneficial effects such as antioxidant, and cytoprotective properties. The purpose of this study ...

Temperature-dependent, behavioural, and transcriptional variability of a tritrophic interaction consisting of bean, herbivorous mite, and predator.

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Ozawa, Rika; Nishimura, Osamu; Yazawa, Shigenobu; Muroi, Atsushi; Takabayashi, Junji; Arimura, Gen-ichiro

2012-11-01

Different organisms compensate for, and adapt to, environmental changes in different ways. In this way, environmental changes affect animal-plant interactions. In this study, we assessed the effect of temperature on a tritrophic system of the lima bean, the herbivorous spider mite Tetranychus urticae and the predatory mite Phytoseiulus persimilis. In this system, the plant defends itself against T. urticae by emitting volatiles that attract P. persimilis. Over 20-40 °C, the emission of volatiles by infested plants and the subsequent attraction of P. persimilis peaked at 30 °C, but the number of eggs laid by T. urticae adults and the number of eggs consumed by P. persimilis peaked at 35 °C. This indicates that the spider mites and predatory mites performed best at a higher temperature than that at which most volatile attractants were produced. Our data from transcriptome pyrosequencing of the mites found that P. persimilis up-regulated gene families for heat shock proteins (HSPs) and ubiquitin-associated proteins, whereas T. urticae did not. RNA interference-mediated gene suppression in P. persimilis revealed differences in temperature responses. Predation on T. urticae eggs by P. persimilis that had been fed PpHsp70-1 dsRNA was low at 35 °C but not at 25 °C when PpHsp70-1 expression was very high. Overall, our molecular and behavioural approaches revealed that the mode and tolerance of lima bean, T. urticae and P. persimilis are distinctly affected by temperature variability, thereby making their tritrophic interactions temperature dependent. © 2012 Blackwell Publishing Ltd.

Koch fractals in physical optics and their Fraunhofer diffraction patterns

Czech Academy of Sciences Publication Activity Database

Horváth, P.; Šmíd, Petr; Vašková, I.; Hrabovský, M.

2010-01-01

Roč. 121, č. 2 (2010), s. 206-2134 ISSN 0030-4026 R&D Projects: GA MŠk(CZ) 1M06002 Institutional research plan: CEZ:AV0Z10100522 Keywords : Koch fractal s * Fraunhofer diffraction patterns Subject RIV: BH - Optics, Masers, Lasers Impact factor: 0.454, year: 2010

CRITERIOS PARA LA PRODUCCIÓN DE Phytoseiulus persimilis (PARASITIFORMES: PHYTOSEIIDAE BAJO CONDICIONES DE INVERNADERO

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Mauricio Alberto Daza Vallejos

2010-01-01

Full Text Available El ácaro depredador Phytoseiulus persimilis ha sido usado con éxito para el control del ácaro fitófago Tetranychus urticae, el cual constituye  una de las plagas mas importantes en los cultivos de rosa de la Sabana de Bogotá. En Colombia esta estrategia de control se ha visto limitada por la falta de disponibilidad de los depredadores en el comercio del producto. En el presente trabajo se proponen criterios para estandarizar las bases para la producción de P. persimilis en plantas de frijol infestadas con poblaciones de T. urticae de diferentes tiempos de desarrollo, utilizando una proporción constante de depredadores liberados. Se encontró que plantas infestadas con poblaciones de T. urticae por más de tres semanas permiten obtener mayores incrementos de población de los depredadores y que aproximadamente a los 25 días después de realizada la liberación, de los depredadores en las plantas infestadas, se obtienen los mayores poblaciones del depredador en estado de ninfa y adulto para cosechar, y usar como estrategia de control en los cultivos.

Phytoseiulus persimilis response to herbivore-induced plant volatiles as a function of mite-days.

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Nachappa, Punya; Margolies, David C; Nechols, James R; Loughin, Thomas

2006-01-01

The predatory mite, Phytoseiulus persimilis (Acari: Phytoseiidae), uses plant volatiles (i.e., airborne chemicals) triggered by feeding of their herbivorous prey, Tetranychus urticae (Acari: Tetranychidae), to help locate prey patches. The olfactory response of P. persimilis to prey-infested plants varies in direct relation to the population growth pattern of T. urticae on the plant; P. persimilis responds to plants until the spider mite population feeding on a plant collapses, after which infested plants do not attract predators. It has been suggested that this represents an early enemy-free period for T. urticae before the next generation of females is produced. We hypothesize that the mechanism behind the diminished response of predators is due to extensive leaf damage caused by T. urticae feeding, which reduces the production of volatiles irrespective of the collapse of T. urticae population on the plant. To test this hypothesis we investigated how the response of P. persimilis to prey-infested plants is affected by: 1) initial density of T. urticae, 2) duration of infestation, and 3) corresponding leaf damage due to T. urticae feeding. Specifically, we assessed the response of P. persimilis to plants infested with two T. urticae densities (20 or 40 per plant) after 2, 4, 6, 8, 10, 12 or 14 days. We also measured leaf damage on these plants. We found that predator response to T. urticae-infested plants can be quantified as a function of mite-days, which is a cumulative measure of the standing adult female mite population sampled and summed over time. That is, response to volatiles increased with increasing numbers of T. urticae per plant or with the length of time plant was infested by T. urticae, at least as long at the leaves were green. Predatory mites were significantly attracted to plants that were infested for 2 days with only 20 spider mites. This suggests that the enemy-free period might only provide a limited window of opportunity for T. urticae

Reproductive performance of seven strains of the tomato red spider mite Tetranychus evansi (Acari: Tetranychidae) at five temperatures

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Gotoh, T.; Sugimoto, N.; Pallini, A.

2010-01-01

The tomato red spider mite Tetranychus evansi Baker et Pritchard occurs on solanaceous plants, and causes serious damage to a variety of crops in Africa and Europe. In 2001 this species was also found in Japan, on nightshade (Solanum nigrum L.), and its invasion to solanaceous of agricultural imp...

Modified atmosphere treatments as a potential disinfestation technique for arthropod pests in greenhouses.

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Held, D W; Potter, D A; Gates, R S; Anderson, R G

2001-04-01

Incidental transport of arthropods on plant material can be a significant mode of pest entry into greenhouses. We evaluated the use of controlled atmosphere treatments as a potential way to eliminate arthropod pests on plant propagules (i.e., cuttings or small rooted plants). Lethal exposures to CO2 or N2 were determined for common greenhouse pests including fungus gnat larvae, Bradysia sp.; green peach aphid, Myzus persicae (Sulzer); sweetpotato whitefly, Bemisia sp.; twospotted spider mite, Tetranychus urticae Koch; and western flower thrips, Frankliniella occidentalis (Pergande). We also studied the effect of pest species, life stage, and presence or absence of plants on efficacy of modified atmosphere treatments. Finally, effects of modified atmospheres on plant quality were evaluated for several bedding plant species including begonia, Begonia semperflorens-cultorum Hort. 'Cocktail Series', chrysanthemum, Dendranthema grandiflora Tzvelev., geranium, Pelargonium X hortorum L.H. Bailey, and impatiens, Impatiens wallerana Hook f., and among cultivars of geranium and chrysanthemum. Exposure for 12-18 h to >99% N2 or CO2 caused complete mortality of aphids, mites, thrips, and whiteflies. Fungus gnat larvae were more tolerant of hypoxic conditions. Adult mites and eggs were equally susceptible. For most pests, there was no difference in response to atmospheres modified by CO2 or N2. However, there was variation in response among plant species and cultivars, with effects ranging from delayed flowering to mortality. Despite the possibility of adverse effects on some plants, this work indicates that use of modified atmospheres has potential to eliminate arthropod pests on plant propagules before they are introduced into greenhouses.

Múltiple natural enemies do not improve two spotted spider mite and flower western thrips control in strawberry tunnels

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Gemma Albendín

2015-03-01

Full Text Available Biological control techniques are commonly used in many horticultural crops in Spain, however the application of these techniques to Spanish strawberries are relatively recent. In this study the effectiveness of augmentative biological control techniques to control the two main strawberry (Fragaria xananassa Duchesne pest: the two-spotted spider mite (TSSM, Tetranychus urticae Koch (Acari: Tetranychidae, and the western flower thrips (WFT, Frankliniella occidentalis (Pergande (Thysanoptera: Thripidae, through releases of the predatory mites Phytoseiulus persimilis Athias-Henriot, Neoseiulus californicus (McGregor, Amblyseius swirskii Athias-Henriot (Acari: Phytoseiidae, and Orius laevigatus (Fieber (Heteroptera: Anthocoridae were tested. Two-year results on the performance of treatments using combinations of these biocontrol agents are presented. In both years, all treatments resulted in the reduction of TSSM numbers; but no treatment was better than the release of P. persimilis alone (P < 0.05. TSSM suppression varied among crop phases being greater early in the season. None of the treatments reduced significantly WFT numbers (P < 0.05, and the established economic injury level (EIL was surpassed from March to late April in both years. However, EIL was surpassed less times when treatment included O. laevigatus (2009: 20.7%; 2010: 22.7% of samples. No effect of A. swirskii was observed when this mite was released. Results corroborate that biological control techniques for TSSM and WFT are feasible for high-plastic tunnel strawberries. Under the conditions in our study no additive effects were observed, and there was not advantage in the release of multiple natural enemies.

Evaluation of predatory mites and Acramite for control of twospotted spider mites in strawberries in north central Florida.

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Rhodes, Elena M; Liburd, Oscar E

2006-08-01

Greenhouse and field experiments were conducted from 2003 to 2005 to determine the effectiveness of two predatory mite species, Phytoseiulus persimilis Athias-Henriot and Neoseiulus californicus (McGregor), and a reduced-risk miticide, Acramite 50 WP (bifenazate), for control of twospotted spider mite, Tetranychus urticae Koch, in strawberries (Fragaria x ananassa Duchesne). In greenhouse tests, three treatments consisting of releases of P. persimilis, N. californicus, and an untreated control were evaluated. Both species of predatory mites significantly reduced twospotted spider mite numbers below those found in the control during the first 3 wk of evaluation. However, during week 4, twospotted spider mite numbers on the plants treated with P. persimilis increased and did not differ significantly from the control. Field studies used releases of P. persimilis and N. californicus, applications of Acramite, and untreated control plots. Both N. californicus and P. persimilis significantly reduced populations of twospotted spider mite below numbers recorded in the control plots. During the 2003-2004 field season P. persimilis took longer than N. californicus to bring the twospotted spider mite population under control (< 10 mites per leaflet). Acramite was effective in reducing twospotted spider mite populations below 10 mites per leaflet during the 2003-2004 field season but not during the 2004-2005 field season, possibly because of a late application. These findings indicate that N. californicus releases and properly timed Acramite applications are promising options for twospotted spider mite control in strawberries for growers in north Florida and other areas of the southeast.

Laboratory evaluation of the effect of Beauveria bassiana on the predatory mite Phytoseiulus persimilis (Acari: Phytoseiidae).

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Ullah, Mohammad Shaef; Lim, Un Taek

2017-09-01

Tetranychus urticae Koch (Acari: Tetranychidae), a major pest of many agricultural crops, is mainly controlled with chemical acaricides. However, predatory mites and entomopathogens have been proposed as alternative control agents. In this study, the effect of the BotaniGard ® GHA strain of Beauveria bassiana on the survival, longevity, fecundity, and egg hatch rate of the predatory mite Phytoseiulus persimilis Athias-Henriot (Acari: Phytoseiidae) were studied under laboratory conditions. When B. bassiana was applied directly to P. persimilis eggs at a concentration of 1×10 8 conidia/ml, corrected hatchability was less than 5%, and the corrected mortality of nymphs and adults was not significantly different from control 10days after treatment. Phytoseiulus persimilis nymphs that hatched from treated eggs showed no significant change in their development time, adult female longevity, hatch rate, survival rates over time, or offspring sex ratio. However, significant negative effects on fecundity and life table parameters (net reproductive rate, intrinsic rate of natural increase, mean generation time, finite rate of increase, and doubling time) were found when B. bassiana was applied to the adult stage. Spraying B. bassiana at 1×10 8 conidia/ml on newly emerged adults of P. persimilis caused 44% reduction in the oviposition period, 26% in adult longevity, and 63% in fecundity. Due to these negative effects, B. bassiana should be used with careful adjustment of application timing (first spray B. bassiana and then release P. persimilis) to supplement biological mite control systems using P. persimilis. Copyright © 2017 Elsevier Inc. All rights reserved.

A Study on Genetic Analysis and Extract Cytotoxicity of Scolopendra subspinipes multilans L. Koch

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Kim Sung-Nam

2006-06-01

Full Text Available Objective : The purpose of this study is to investigate nucleotide sequence and extract cytotoxicity of Scolopendrae corpus. The nature and taste of Scolopendrae corpus is hot, Warm and toxic, and the effect of this is dispelling wind, anti-spasmodic action and detoxication so it has been used for C.V.A, facial palsy, sensory disorder at extremities, wounds and arthritis. Methods : Scolopendrae corpus were collected by locality on the market. They were morphologically classified. Their nucleotide sequence was investigated and compared among them. In addition, the water-alcohol extract cytotoxicity of them was studied by MTT-based cytotoxicity assay. Results : It was shown that the each Scolopendrae corpus by locality is almost identical at genetic result and is identified as Scolopendra subspinipes mutilans L. Koch. Nucleotide sequence of Scolopendra subspinipes mutilans L. Koch in this study will help to discriminate other species of Scolopendrae corpus. The water-alcohol extract of Scolopendra subspinipes mutilans L. Koch did not induce cytotoxicity on Hep G2, L929 cell and peritoneal macrophages. Besides, it did not influence nitrite production of peritoneal macrophages. These results can be used as basic data for genetic discrimination with another species of scolopendrae corpus.

Poliitikud kaitsevad saadikute kulude hüvitamise süsteemi / Tuuli Koch

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Koch, Tuuli

2006-01-01

Erakondade juhtpoliitikud on rahul praeguse parlamendiliikmete kulude hüvitamise süsteemiga, mille kohaselt hüvitatakse neile kuludokumentide alusel kulutused kuni 30 protsendi ulatuses palgast. Vt. samas: Tuuli Koch. Künka kosilased. Lisa: Hea teenistus

The efficacy and safety of Urtica dioica in treating Benign Prostatic ...

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Conclusion: This meta-analysis indicates that Urtica dioica to be an effective and ... and no significant adverse effects have been reported by patients after taking ... risk for dichotomous outcomes and the standardized mean difference (SMD) for .... of sex hormone-binding globulin to its receptor on prostate cell membranes ...

Urtica dioica dichloromethane extract induce apoptosis from intrinsic pathway on human prostate cancer cells (PC3).

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Mohammadi, A; Mansoori, B; Aghapour, M; Baradaran, B

2016-03-31

Prostate cancer is considered as the major cause of death among men around the world. There are a number of medicinal plants triggering apoptosis response in cancer cells, thus have a therapeutic potential. Therefore, further studies to characterize beneficial properties of these plants in order to introduce novel anti-cancer drugs are the interest of recent researches on the alternative medicine. On the other hand, due to traditional uses and availability of Urtica dioica extract, we decided to evaluate the efficacy of this medicinal herb on pc3 prostate cancer cell line. In the present study the cytotoxic effects of Urtica dioica extract were assessed by 3-(4, 5-dimethylthiazol-2-yl)-2, 5-diphenyltetrazolium bromide (MTT) assay and trypan blue viability dye. Then, DNA fragmentation and terminal deoxynucleotidyl transferase dUTP nick end labeling (TUNEL) assay were exploited to measure cell death and apoptosis stage. The expression levels of caspase 3, caspase 9 and Bcl-2 genes were quantified by Real-Time PCR. Finally, Cell cycle was analyzed by flow cytometry. MTT assay showed that dichloromethanolic extract of Urtica dioica significantly inhibited the cell growth. According to the DNA fragmentation and TUNEL assay results, the herbal extract was able to induce apoptosis in prostate cancer cells. Our findings also demonstrated that the plant extract substantially increases the caspase 3 and 9 mRNA expression, while decreases Bcl-2. Cell cycle arrest was occurred in G2 stage, due to the results of flow cytometry. These results indicate that dichloromethanolic extract of Urtica dioica can successfully induce apoptosis in PC3 cells. Therefore, it could be used as a novel therapeutic candidate for prostate tumor treatment.

Effect of Urtica dioica L. (Urticaceae) on testicular tissue in STZ-induced diabetic rats.

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Ghafari, S; Balajadeh, B Kabiri; Golalipour, M J

2011-08-15

Urtica dioica L. (Stinging nettle) has already been known for a long time as a medicinal plant in the world. This histopathological and morphometrical study was conducted to determine the effects of the hydroalcoholic extract of Urtica dioica leaves on testis of streptozotocin-induced diabetic rats. Eighteen male Wistar rats were allocated to equally normal, diabetic and treatment groups. Hyperglycemia was induced by Streptozotocin (80 mg kg(-1)) in animals of diabetic and treatment groups. One week after STZ injection (80 mg kg(-1)), the rats of treatment group received the extract of U. dioica (100 mg/kg/day) IP for 28 days. After 5 weeks of study, all the rats were sacrificed and testes were removed and fixed in bouin and after tissue processing stained with H and E technique. Tubular cell disintegration, sertoli and spermatogonia cell vacuolization and decrease in sperm concentration in seminiferous tubules were seen in diabetic and treatment groups group in comparison with control. External Seminiferous Tubular Diameter (STD) and Seminiferous Epithelial Height (SEH) significantly reduced (p < 0.05) in the diabetic rats compared with controls and these parameters in the treatment group were similar to diabetics animals. This study showed that hydroalcoholic extract of Urtica dioica leaves, after induction of diabetes; has no treatment effect on seminiferous tubules alterations in streptozotocin-induced diabetic rats.

Damage caused by Tetranychus Merganser Bondreaux (Acari: Tetranychidae on Nopal Verdura Opuntia Ficus-Indica (L. Miller during winter

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J. Lima-Espíndola

2017-09-01

Full Text Available The spider mite Tetranychus merganser occurs in some crops in Mexico and USA. This mite could be considered a potential pest in countries like Japan. In this work we recorded the damages that T. merganser causes to the nopal verdura (prickly pear vegetable crop in one of the principal cactus crop regions of Mexico.

Antioxidant and apoptotic effects of an aqueous extract of Urtica dioica on the MCF-7 human breast cancer cell line.

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Fattahi, Sadegh; Ardekani, Ali Motevalizadeh; Zabihi, Ebrahim; Abedian, Zeinab; Mostafazadeh, Amrollah; Pourbagher, Roghayeh; Akhavan-Niaki, Haleh

2013-01-01

Breast cancer is the most prevalent cancer and one of the leading causes of death among women in the world. Plants and herbs may play an important role in complementary or alternative treatment. The aim of this study was to evaluate the antioxidant and anti-proliferative potential of Urtica dioica. The anti oxidant activity of an aqueous extract of Urtica dioica leaf was measured by MTT assay and the FRAP method while its anti-proliferative activity on the human breast cancer cell line (MCF-7) and fibroblasts isolated from foreskin tissue was evaluated using MTT assay. Mechanisms leading to apoptosis were also investigated at the molecular level by measuring the amount of anti and pro-apoptotic proteins and at the cellular level by studying DNA fragmentation and annexin V staining by flow cytometry. The aqueous extract of Urtica dioica showed antioxidant effects with a correlation coefficient of r(2)=0.997. Dose-dependent and anti-proliferative effects of the extract were observed only on MCF-7 cells after 72 hrs with an IC50 value of 2 mg/ml. This anti proliferative activity was associated with an increase of apoptosis as demonstrated by DNA fragmentation, the appearance of apoptotic cells in flow cytometry analysis and an increase of the amount of calpain 1, calpastatin, caspase 3, caspase 9, Bax and Bcl-2, all proteins involved in the apoptotic pathway. This is the first time such in vitro antiproliferative effect of aqueous extract of Urtica dioica leaf has been described for a breast cancer cell line. Our findings warrant further research on Urtica dioica as a potential chemotherapeutic agent for breast cancer.

Phytochemical, phylogenetic, and anti-inflammatory evaluation of 43 Urtica accessions (stinging nettle) based on UPLC-Q-TOF-MS metabolomic profiles.

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Farag, Mohamed A; Weigend, Maximilian; Luebert, Federico; Brokamp, Grischa; Wessjohann, Ludger A

2013-12-01

Several species of the genus Urtica (especially Urtica dioica, Urticaceae), are used medicinally to treat a variety of ailments. To better understand the chemical diversity of the genus and to compare different accessions and different taxa of Urtica, 63 leaf samples representing a broad geographical, taxonomical and morphological diversity were evaluated under controlled conditions. A molecular phylogeny for all taxa investigated was prepared to compare phytochemical similarity with phylogenetic relatedness. Metabolites were analyzed via UPLC-PDA-MS and multivariate data analyses. In total, 43 metabolites were identified, with phenolic compounds and hydroxy fatty acids as the dominant substance groups. Principal component analysis (PCA) and hierarchical clustering analysis (HCA) provides a first structured chemotaxonomy of the genus. The molecular data present a highly resolved phylogeny with well-supported clades and subclades. U. dioica is retrieved as both para- and polyphyletic. European members of the U. dioica group and the North American subspecies share a rather similar metabolite profile and were largely retrieved as one, nearly exclusive cluster by metabolite data. This latter cluster also includes - remotely related - Urtica urens, which is pharmaceutically used in the same way as U. dioica. However, most highly supported phylogenetic clades were not retrieved in the metabolite cluster analyses. Overall, metabolite profiles indicate considerable phytochemical diversity in the genus, which largely falls into a group characterized by high contents of hydroxy fatty acids (e.g., most Andean-American taxa) and another group characterized by high contents of phenolic acids (especially the U. dioica-clade). Anti-inflammatory in vitro COX1 enzyme inhibition assays suggest that bioactivity may be predicted by gross metabolic profiling in Urtica. Copyright © 2013. Published by Elsevier Ltd.

Protective effect of Urtica dioica methanol extract against experimentally induced urinary calculi in rats.

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Zhang, Haiying; Li, Ning; Li, Kun; Li, Peng

2014-12-01

Renal calculi formation is one of the most common urological disorders. Urinary stone disease is a common disease, which affects 10‑12% of the population in industrialized countries. In males, the highest prevalence of the disease occurs between the age of 20 and 40 years, while in females, the highest incidence of the disease occurs later. Previous studies have shown that long‑term exposure to oxalate is toxic to renal epithelial cells and results in oxidative stress. In the present study, a methanolic extract of aerial parts of Urtica dioica was screened for antiurolithiatic activity against ethylene glycol and ammonium chloride‑induced calcium oxalate renal stones in male rats. In the control rats, ethylene glycol and ammonium chloride administration was observed to cause an increase in urinary calcium, oxalate and creatinine levels, as well as an increase in renal calcium and oxalate deposition. Histopathological observations revealed calcium oxalate microcrystal deposits in the kidney sections of the rats treated with ethylene glycol and ammonium chloride, indicating the induction of lithiasis. In the test rats, treatment with the methanolic extract of Urtica dioica was found to decrease the elevated levels of urinary calcium, oxalate and creatinine, and significantly decrease the renal deposition of calcium and oxalate. Furthermore, renal histological observations revealed a significant reduction in calcium oxalate crystal deposition in the test rats. Phytochemical analysis of the Urtica dioica extract was also performed using liquid chromatography‑electrospray ionization tandem mass spectrometry and high-performance liquid chromatography with photodiode array detection, to determine the chemical composition of the extract. The eight chemical constituents identified in the extract were protocatechuic acid, salicylic acid, luteolin, gossypetin, rutin, kaempferol‑3‑O‑rutinoside, kaempferol‑3‑O‑glucoside and chlorogenic acid. In conclusion

Insulin mimetics in Urtica dioica: structural and computational analyses of Urtica dioica extracts.

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Domola, Masoud Shabani; Vu, Vivian; Robson-Doucette, Christine A; Sweeney, Gary; Wheeler, Michael B

2010-06-01

Urtica Dioica (UD) is a plant shown to reduce blood glucose levels upon oral ingestion; however, neither its active component nor its mechanism of action has been identified. One active fraction of this extract, termed UD-1, was separated by molecular sieve column chromatography and purified by high performance liquid chromatography (HPLC). While UD-1 did not stimulate insulin secretion in glucose-responsive MIN6 clonal beta-cells, chronic exposure (24 h) significantly enhanced glucose uptake (approximately 1.5-fold) in L6-GLUT4myc myoblast cells. Using HPLC and MALDI-TOF, we further purified the UD-1 fraction into two fractions termed UD-1A and UD-1B. Computational and structural analyses strongly suggested that the antidiabetic component of UD-1 was due to one or more structurally related cyclical peptides that facilitate glucose uptake by forming unique glucose permeable pores. The structure and function of these glucose-conducting pores are discussed herein.

Conservation biological control in strawberry: effect of different pollen on development, survival, and reproduction of Neoseiulus californicus (Acari: Phytoseiidae).

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Gugole Ottaviano, María F; Cédola, Claudia V; Sánchez, Norma E; Greco, Nancy M

2015-12-01

Wild vegetation surrounding crops may provide temporary habitat and potential food sources for phytoseiids in different seasons. Monthly vegetation samples of wild plants adjacent to strawberry plants and wild plants in a vegetation strip close to the crop were taken. The frequency of Neoseiulus californicus, Tetranychus urticae and other mites and insects was recorded. In addition, in a laboratory assay, the survival, developmental time and fecundity of females fed on pollen of strawberry and pollen of wild plants where N. californicus was recorded during their flowering, were estimated. Pollen from Urtica urens, Lamium amplexicaule, Convolvulus arvensis, Sonchus oleraceous, Galega officinalis, and Fragaria x ananassa (strawberry) allowed development of N. californicus to adult, but not reproduction. Survival was 70-80 % when fed on pollen from S. oleraceus, G. officinalis and C. arvensis, 80-90 % when fed on pollen from U. urens and F. x ananassa, and more than 90 % when fed on T. urticae and on pollen from L. amplexicaule. In autumn and winter, U. urens, L. amplexicaule and S. oleraceous could promote the persistence of N. californicus when prey density in strawberry is low, offering T. urticae, thrips and pollen. In summer, pollen of C. arvensis and G. officinalis would contribute to the persistence of N. californicus when the strawberry crop is ending and offers scarce food resources. Although the pollen of these plants would not enable the predator population to increase, the presence of these plants in the vicinity of strawberry could contribute to the persistence of N. californicus population and help to limit T. urticae growth when this pest begins to colonize the crop.

AROMA PROFILE AND ANTIMICROBIAL PROPERTIES OF ALCOHOLIC AND AQUEOUS EXTRACTS FROM ROOT, LEAF AND STALK OF NETTLE (Urtica dioica L.)

OpenAIRE

Razzagh Mahmoudi; Kiumars Amini; Omid Fakhri; Mahsa Alem

2014-01-01

Medicinal plant can be considered as a great source of new antimicrobial agents due to their enormous therapeutic potential and limited side effects. Nettle (Urtica dioica L.) is a widespread and common medicinal plant widely used in traditional medicine. The present study investigates the antimicrobial potency of alcoholic and aqueous extracts of Urtica dioica on some gram positive and negative bacteria and also a particular type of fungi and analyzes the extracts to find the active ingredie...

Effect of Urtica Dioica Decoction on Serum Glucose and Lipid Profile in Stereptozotocin Induced Diabetic Male Rats

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Mohammad Reza Sahraki

Full Text Available Background: Since Urtica dioica is a traditional treatment plant and is used for antihypertensive, antilipidemic and antidiabetic agents, this survey was carried out to evaluate the effect of Urtica dioica decoction on serum glucose and lipid profile in diabetic male rats induced by stereptozotocin (STZ. Materials and Methods: This experiment was performed on 30 Wistar-Albino male rats, weighing 200-250 g, which were divided in sham control (A, diabetic control (B and diabetic test groups (C randomly (N=10. Type I diabetes was induced by single intraperitoneal injection of STZ (65 mg/kg. Test group received 0.40-0.60 ml of Urtica dioica decoction for a month by gavages, control group (B received the same volume of distill water. Group (A did not receive any agent during the experiment period. Finally, animals were anesthetized, sacrificed and blood samples were collected from the cervical vein. Then, serum glucose and lipid profiles were measured by ordinary methods. Data were analyzed by SPSS-11, using ANOVA and post hoc Tukey tests. Results were expressed as mean±SD, and statistical difference was considered significant by p<0.05.Results: Results in the present study showed that fasting blood glucose (FBS, total cholesterol (TCho, triglyceride (TG, LDL, food and water intake were significantly decreased in group C compared with those of group B, but body weight gain was significantly increased compared with that of control group (B.Conclusion: These results indicated that Urtica dioica decoction caused decreased FBS and improved serum lipids in diabetic male rats. Some more studies have shown the same mechanism.

Urtica dioica extract suppresses miR-21 and metastasis-related genes in breast cancer.

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Mansoori, Behzad; Mohammadi, Ali; Hashemzadeh, Shahriar; Shirjang, Solmaz; Baradaran, Ali; Asadi, Milad; Doustvandi, Mohammad Amin; Baradaran, Behzad

2017-09-01

Breast cancer has a high prevalence among women worldwide. Tumor invasion and metastasis still remains an open issue that causes most of the therapeutic failures and remains the prime cause of patient mortality. Hence, there is an unmet need to develop the most effective therapeutic approach with the lowest side effects and highest cytotoxicity that will effectively arrest or eradicate metastasis. An MTT assay and scratch test were used to assess the cytotoxicity and migration effects of Urtica dioica on the breast cancer cells. The QRT-PCR was used to study the expression levels of miR-21, MMP1, MMP9, MMP13, CXCR4, vimentin, and E-cadherin. The results of gene expression in tumoral groups confirmed the overexpression of miR-21, MMP1, MMP9, MMP13, vimentin, and CXCR4, and the lower expression of E-cadherin compared to control groups (PUrtica dioica significantly inhibited breast cancer cell proliferation. Moreover, findings from the scratch assay exhibited the inhibitory effects of Urtica dioica on the migration of breast cancer cell lines. Urtica dioica extract could inhibit cancer cell migration by regulating miR-21, MMP1, MMP9, MMP13, vimentin, CXCR4, and E-Cadherin. Moreover, our findings demonstrated that the extract could decrease miR-21 expression, which substantially lessens the overexpressed MMP1, MMP9, MMP13, vimentin, and CXCR4 and increases E-cadherin in the tumoral group. Copyright © 2017 Elsevier Masson SAS. All rights reserved.

Apoptotic Effect of the Urtica Dioica Plant Extracts on Breast Cancer Cell Line (MDA- MB- 468

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A Mohammadi

2015-09-01

Full Text Available Background & objectives: Cancer is one of the most causes of mortality in worldwide. Components derived from natural plants that induce apoptosis are used for cancer treatment. Therefore investigation of different herbal components for new anti-cancer drug is one of the main research activities throughout the world. According to low cost, oral consumption and easy access to the public extracts of Urtica dioica, in this study we aimed to investigate the effectiveness of this herb on MDA-MB-468 breast cancer cells.   Methods: Cytotoxic effect of Urtica dioica extract was measured using MTT assays. To show induction of apoptosis by this plant TUNEL and DNA Fragmentation test were performed.   Results: In the present study dichloromethane extracts noticeably killed cancer cells. IC50 values related to human breast adenocarcinoma cell line MDA-MB-468 were 29.46±1.05 µg/ml in 24 hours and 15.54±1.04 µg/ml in 48 hours. TUNEL test and DNA Fragmentation assay showed apoptotic characteristic in the extract treated cells.   Conclusion: The results showed that MDA-MB-468 cells after treatment with dichloromethane extract of Urtica dioica, induces apoptosis in MDA-MB-468 cancer cells which may be useful in the treatment of cancer.

Salix transect of Europe: structured genetic variation and isolation-by-distance in the nettle psyllid, Trioza urticae (Psylloidea, Hemiptera), from Greece to Arctic Norway

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Wonglersak, Rungtip; Cronk, Quentin; Percy, Diana

2017-01-01

Abstract Background The common nettle (Urtica dioica L.) is co-associated with willows (Salix spp.) in riparian habitats across Europe. We sampled the widespread nettle psyllid, Trioza urticae (Linné, 1758), from Urtica in willow habitats on a megatransect of Europe from the Aegean to the Arctic Ocean. The aim of this study was to use an unusually widespread insect to assess the influence of geographic distances and natural geographic barriers on patterns of genetic variation and haplotype distribution. New information Phylogeographic analysis using DNA sequences of two mtDNA regions, COI and cytB, shows that T. urticae specimens are organized into four regional groups (southern, central, northern and arctic). These groups are supported by both phylogenetic analysis (four geographically-based clades) and network analysis (four major haplotype groups). The boundary between southern and central groups corresponds to the Carpathian Mountains and the boundary between the central and northern groups corresponds to the Gulf of Finland. Overall these groups form a latitudinal cline in genetic diversity, which decreases with increasing latitude. PMID:28325977

Beyond Predation: The Zoophytophagous Predator Macrolophus pygmaeus Induces Tomato Resistance against Spider Mites.

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Maria L Pappas

Full Text Available Many predatory insects that prey on herbivores also feed on the plant, but it is unknown whether plants affect the performance of herbivores by responding to this phytophagy with defence induction. We investigate whether the prior presence of the omnivorous predator Macrolophus pygmaeus (Rambur on tomato plants affects plant resistance against two different herbivore species. Besides plant-mediated effects of M. pygmaeus on herbivore performance, we examined whether a plant defence trait that is known to be inducible by herbivory, proteinase inhibitors (PI, may also be activated in response to the interactions of this predator with the tomato plant. We show that exposing tomato plants to the omnivorous predator M. pygmaeus reduced performance of a subsequently infesting herbivore, the two-spotted spider mite Tetranychus urticae Koch, but not of the greenhouse whitefly Trialeurodes vaporariorum (Westwood. The spider-mite infested tomato plants experience a lower herbivore load, i.e., number of eggs deposited and individuals present, when previously exposed to the zoophytophagous predator. This effect is not restricted to the exposed leaf and persists on exposed plants for at least two weeks after the removal of the predators. The decreased performance of spider mites as a result of prior exposure of the plant to M. pygmaeus is accompanied by a locally and systemically increased accumulation of transcripts and activity of proteinase inhibitors that are known to be involved in plant defence. Our results demonstrate that zoophytophagous predators can induce plant defence responses and reduce herbivore performance. Hence, the suppression of populations of certain herbivores via consumption may be strengthened by the induction of plant defences by zoophytophagous predators.

Chemical composition and acaricidal activity of the essential oils from Vitex agnus-castus L. (Verbenaceae and selected monoterpenes

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Roberta C.S. Neves

2016-01-01

Full Text Available ABSTRACT Tetranychus urticae is considered one of the main plagues in the world. Its occurrence in Pernambuco was registered for the first time in 1985 and it has caused considerable damage to the farmers, attacking different cultures of agricultural interest. The essential oils from different parts of Vitex agnus-castus harvested in the Atlantic forest in the state of Pernambuco, Brazil, were obtained by hydrodistillation and the acaricidal potential was evaluated against Tetranychus urticae using two methods under laboratory conditions. Gas chromatography-mass spectrometry revealed the presence of 47 components accounting for 98.8 ± 0.0%, 93.0 ± 0.1% and 97.4 ± 1.0% of the essential oils from the leaves, fruit and inflorescence, respectively. The compounds 1,8-cineole and β-(E-farnesene were the major components of the oils from the leaves (17.6 ± 0.3% and 13.6 ± 0.2%, respectively and fruit (17.5 ± 0.1% and 15.4 ± 0.0%, respectively. β-(E-farnesene (13.5 ± 0.1% and β-caryophyllene (11.7 ± 0.1% were the major components of the oils from the flowers. Acaricidal action varied depending on the part of the plant and method employed. Through fumigation, the oil from the leaves (CL50= 0.61 μL L-1 of air was approximately six fold more toxic than the oil from the fruit. However, through residual contact, the oil from the fruit (CL50 = 137.11 μLmL-1 was 1.1 fold more toxic than the oil from the leaves. The relationship between the chemical composition of the oils and acaricidal activity is also presented.

Chemical composition and acaricidal activity of the essential oils from Vitex agnus-castus L. (Verbenaceae) and selected monoterpenes.

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Neves, Roberta C S; Camara, Claudio A G da

2016-09-01

Tetranychus urticae is considered one of the main plagues in the world. Its occurrence in Pernambuco was registered for the first time in 1985 and it has caused considerable damage to the farmers, attacking different cultures of agricultural interest. The essential oils from different parts of Vitex agnus-castus harvested in the Atlantic forest in the state of Pernambuco, Brazil, were obtained by hydrodistillation and the acaricidal potential was evaluated against Tetranychus urticae using two methods under laboratory conditions. Gas chromatography-mass spectrometry revealed the presence of 47 components accounting for 98.8 ± 0.0%, 93.0 ± 0.1% and 97.4 ± 1.0% of the essential oils from the leaves, fruit and inflorescence, respectively. The compounds 1,8-cineole and β-(E)-farnesene were the major components of the oils from the leaves (17.6 ± 0.3% and 13.6 ± 0.2%, respectively) and fruit (17.5 ± 0.1% and 15.4 ± 0.0%, respectively). β-(E)-farnesene (13.5 ± 0.1%) and β-caryophyllene (11.7 ± 0.1%) were the major components of the oils from the flowers. Acaricidal action varied depending on the part of the plant and method employed. Through fumigation, the oil from the leaves (CL50= 0.61 μL L-1 of air) was approximately six fold more toxic than the oil from the fruit. However, through residual contact, the oil from the fruit (CL50 = 137.11 μLmL-1) was 1.1 fold more toxic than the oil from the leaves. The relationship between the chemical composition of the oils and acaricidal activity is also presented.

Urtica dioica (Stinging Nettle): A Neglected Plant With Emerging Growth Promoter/Immunostimulant Properties for Farmed Fish.

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De Vico, Gionata; Guida, Vincenzo; Carella, Francesca

2018-01-01

Urtica dioica (stinging nettle), is a perennial plant belonging to the family of Urticaceae , genus Urtica . Despite the use of nettle in folk veterinary medicine is well documented, U. dioica is today an underestimated and frequently neglected plant, considered by the contemporary agriculture as a weed to be eliminated. This mini review focus on very recent studies on dietary administration of U. dioica , both as a single herb or in combination with other herbs, to enhance growth and stimulate farmed fish immunity, thus enabling the fish to be more resistant against bacterial infections. Such an emerging feature, together with cost-effectiveness, adequate availability, and easy processing of nettle, could make this herb an excellent, inexpensive and widely used dietary supplement on intensive fish farms.

Urtica dioica (Stinging Nettle): A Neglected Plant With Emerging Growth Promoter/Immunostimulant Properties for Farmed Fish

Science.gov (United States)

De Vico, Gionata; Guida, Vincenzo; Carella, Francesca

2018-01-01

Urtica dioica (stinging nettle), is a perennial plant belonging to the family of Urticaceae, genus Urtica. Despite the use of nettle in folk veterinary medicine is well documented, U. dioica is today an underestimated and frequently neglected plant, considered by the contemporary agriculture as a weed to be eliminated. This mini review focus on very recent studies on dietary administration of U. dioica, both as a single herb or in combination with other herbs, to enhance growth and stimulate farmed fish immunity, thus enabling the fish to be more resistant against bacterial infections. Such an emerging feature, together with cost-effectiveness, adequate availability, and easy processing of nettle, could make this herb an excellent, inexpensive and widely used dietary supplement on intensive fish farms. PMID:29632497

Inhibitory effects of Urtica dioica L. root on electrophysiological properties of isolated rabbit atrioventricular node

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A. Enayati

2017-11-01

Full Text Available Background and objectives: The ideal drug for treatment of a wide range of supraventricular arrhythmia hasn't yet been developed. Previous studies have shown antihypertensive and negative inotropic effects of the Urtica dioica L. (nettle. Therefore, the aim of present study is to determine the rate dependent inhibitory effects of ethanol extract of nettle root and investigate the role of adrenoceptors in the anti-arrhythmic mechanism of nettle on the isolated rabbit atrio-ventricular node. Methods: Urtica dioica roots were collected from Gorgan (Golestan, Iran. Male New Zealand rabbits (n=7 were used in all of the experiments. Experimental stimulation protocols (WBCL; Recovery, Facilitation, Fatigue were applied to assess electrophysiological properties of Node. All protocols were repeated in the presence and absence (control of different concentration (0.25-0.5 w/v % of nettle and 1 μM nadolol. Data were shown as Mean±SE, difference between groups statistically were assessed by SPSS software. Results: Nettle (0.5 w/v significantly decreased basic and functional properties of node as WBCL, ERP, FRP, AVCT and magnitude of fatigue (∆AH significantly increased but ∆FRP significantly decreased. In the presence of nadolol (1μM as a nonselective β-blocker, nettle (0.3 mg/L could not repeat its effects on electrophysiological properties of AV-node. Conclusion: The results showed the modifying properties of Urtica dioica root extract. It may be considered as a candidate for the treatment of supraventicular arrhythmias.

Diocanol; one new phenol derivative isolated and characterized from Urtica dioica

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Riaz Ullah

2017-02-01

Full Text Available One new benzene derivative Diocanol(1 was isolated from the ethyl acetate soluble portion of the whole plant of Urtica dioica along with known constituents β-amyrin (2, β-sitosterol (3, stigmasterol (4, and oleanolic acid (5. The structures of the isolated compounds were characterized based on 1H and 13C NMR spectra, including two-dimensional NMR techniques like COSY, HMQC, and HMBC and compared with the literature data.

Renal and vascular studies of aqueous extract of Urtica dioica in rats and rabbits

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K.F. Dizaye

2013-06-01

Full Text Available Urtica dioica has a variety of uses in traditional medicine for genitourinary ailments kidney disorders, allergies, diabetes, anemia, gastrointestinal tract ailments, musculoskeletal aches and alopecia. However, only a few of these uses have scientific bases that support their clinical uses. This study was done to evaluate some of the in vivo and in vitro pharmacological actions of this plant. Eighteen local domestic rabbits (Oryctolagus cuniculus were used for in vitro studies (effect of the plant extract on isolated pulmonary arteries and isolated urinary bladder smooth muscle and in vivo studies (effect of the extract on renal function. Six male albino rats were used for studying the effects of the plant extract on blood pressure and heart rate. Urtica dioica extract produced a significant increase in urine volume and urinary Na+ excretion without significant changes in K+ excretion rates in experimental rabbits. No changes occurred in Glomerular filtration rate and %Na+ reabsorption of filtered load. Neither vasodilatation nor vasoconstriction of isolated pulmonary arteries of the rabbit was seen after applying the aqueous extract of U. dioica. Besides it could not reverse the vasoconstrictor effect of phenylephrine. Urtica dioica has no detectable effects on the isolated bladder; moreover it did not reverse the contraction that was produced by pilocarpine. In experimental rats, the plant extract produced a profound drop in blood pressure associated with decreased heart rate. In conclusion the aqueous extract of U. dioica produced diuretic and natriuretic effects with out significant effect on the K+ excretion rate in rabbits. Moreover it produced a profound drop in blood pressure and heart rate.

Lignans from the roots of Urtica dioica and their metabolites bind to human sex hormone binding globulin (SHBG).

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Schöttner, M; Gansser, D; Spiteller, G

1997-12-01

Polar extracts of the stinging nettle (Urtica dioica L.) roots contain the ligans (+)-neoolivil, (-)-secoisolariciresinol, dehydrodiconiferyl alcohol, isolariciresinol, pinoresinol, and 3,4-divanillyltetrahydrofuran. These compounds were either isolated from Urtica roots, or obtained semisynthetically. Their affinity to human sex hormone binding globulin (SHBG) was tested in an in vitro assay. In addition, the main intestinal transformation products of plant lignans in humans, enterodiol and enterolactone, together with enterofuran were checked for their activity. All lignans except (-)-pinoresinol developed a binding affinity to SHBG in the in vitro assay. The affinity of (-)-3,4-divanillyltetrahydrofuran was outstandingly high. These findings are discussed with respect to potential beneficial effects of plant lignans on benign prostatic hyperplasia (BPH).

Effect of Urtica dioica on morphometric indices of kidney in streptozotocin diabetic rats--a stereological study.

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Golalipour, Mohammad Jafar; Gharravi, Anneh Mohammad; Ghafari, Sorya; Afshar, Mohammad

2007-11-01

The aim of the present study was to investigate the effect of Urtica dioica on Morphometric indices of kidney in diabetic rats. Thirty male adult albino wistar rats of 125-175 g divided into control, diabetic and Urtica dioica treatment groups. In treatment Group, diabetic rats received 100 mg kg(-1) daily hydroalcoholic extract of U. dioica intraperitoneally for 4 weeks. After the animals had been sacrified, the kidneys were removed and fixed by formaldehyde, cut horizontally into 1 mm slices and processed, Stained with H and E. Stereological study performed using light microscope and the image projected on a table of olysa software. Cavalieri principle was used to estimate the volume of cortex, medulla and whole kidney. All the grouped data statistically evaluated using Student's t-test, expressed as the Mean +/- SE. Ration of kidney weight/body weight in diabetes (0.51) and diabetes-extract group (0.67) were higher then control group (0.42). Ratio of kidney volume/body weight in diabetes (350) and diabetes-extract group (348) were higher then control group (323). Volume Ratio of cortex/medulla in diabetes-extract group (1.65) was higher then control (1.34) and diabetes group (1.33). Glomerular area and diameter and proximal tubule diameter in diabetes-Extract group was higher than control and diabetes groups. This study revealed that Urtica dioica has no effect on renal morphometric indices in induced diabetic rats.

Antidiabetic Effect of Hydroalcholic Urtica dioica Leaf Extract in Male Rats with Fructose-Induced Insulin Resistance

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Ahangarpour, Akram; Mohammadian, Maryam; Dianat, Mahin

2012-01-01

Background: Urtica dioica has been used as antihypertensive, antihyperlipidemic and antidiabetic herbal medicine. The purpose of this study was to study the effect of hydroalcoholic extract of Urtica dioica on fructose-induced insulin resistance rats. Methods: Forty male Wistar rats were randomly divided into five groups including control, fructose, extract 50, extract 100 and extract 200. The control rat received vehicle, the fructose and extract groups received fructose 10% for eight weeks. The extract groups received single daily injection of vehicle, 50, 100 or 200 mg/kg/day for the two weeks. Blood glucose, insulin, last fasting insulin resistance index (FIRI), serum triglyceride (TG), low-density lipoprotein (LDL), very low-density lipoprotein (VLDL), high-density lipoprotein (HDL), alanin trasaminase (AST) and alkaline phosphatase (ALP), leptin and LDL/HDL ratio were determined. Results: Compared to control group, daily administration of fructose was associated with significant increase in FIRI, blood glucose and insulin, significant decrease in lepin, and no significant change in TG, HDL, LDL, LDL/HDL ratio, VLDL, ALT, and ALP. The extract significantly decreased serum glucose, insulin, LDL and leptin, and LDL/HDL ratio and FIRI. It also significantly increased serum TG, VLDL, and AST, but did not change serum ALP. Conclusion: We suggest that Urtica dioica extract, by decreasing serum glucose, and FIRI, may be useful to improve type 2 diabetes mellitus. Also, by positive effect on lipid profile and by decreasing effect on leptin, it may improve metabolic syndrome. PMID:23115450

Antidiabetic Effect of Hydroalcholic Urtica dioica Leaf Extract in Male Rats with Fructose-Induced Insulin Resistance

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Akram Ahangarpour

2012-09-01

Full Text Available Background: Urtica dioica has been used as antihypertensive, antihyperlipidemic and antidiabetic herbal medicine. The purpose of this study was to study the effect of hydroalcoholic extract of Urtica dioica on fructose-induced insulin resistance rats. Methods: Forty male Wistar rats were randomly divided into five groups including control, fructose, extract 50, extract 100 and extract 200. The control rat received vehicle, the fructose and extract groups received fructose 10% for eight weeks. The extract groups received single daily injection of vehicle, 50, 100 or 200 mg/kg/day for the two weeks. Blood glucose, insulin, last fasting insulin resistance index (FIRI, serum triglyceride (TG, low-density lipoprotein (LDL, very low-density lipoprotein (VLDL, high-density lipoprotein (HDL, alanin trasaminase (AST and alkaline phosphatase (ALP, leptin and LDL/HDL ratio were determined.Results: Compared to control group, daily administration of fructose was associated with significant increase in FIRI, blood glucose and insulin, significant decrease in lepin, and no significant change in TG, HDL, LDL, LDL/HDL ratio, VLDL, ALT, and ALP. The extract significantly decreased serum glucose, insulin, LDL and leptin, and LDL/HDL ratio and FIRI. It also significantly increased serum TG, VLDL, and AST, but did not change serum ALP.Conclusion: We suggest that Urtica dioica extract, by decreasing serum glucose, and FIRI, may be useful to improve type 2 diabetes mellitus. Also, by positive effect on lipid profile and by decreasing effect on leptin, it may improve metabolic syndrome.

The Effects of Rumex patientia L. and Urtica dioica L. on Some Blood and Urine Parameters, and Liver and Kidney Histology in Diabetic Rats

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GÜNEŞ, Hasan V.

2014-01-01

The effects of Rumex patientia and Urtica dioica on levels of blood glucose, plasma amino acids and other parameters, urine excreta, and liver and kidney histology were examined in diabetic rats induced by streptozotocin. Streptozotocin increased blood glucose and changed the levels of amino acids and other parameters, and caused degenerative changes in the liver and kidney. Rumex patientia had some protective effect on these parameters changed by streptozotocin, while Urtica dioci...

Effects of Urtica dioica dichloromethane extract on cell apoptosis and related gene expression in human breast cancer cell line (MDA-MB-468).

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Mohammadi, A; Mansoori, B; Goldar, S; Shanehbandi, D; Khaze, V; Mohammadnejad, L; Baghbani, E; Baradaran, B

2016-02-29

Breast cancer is the most common cancer among women in worldwide, especially in developing countries. Therefore, a large number of anticancer agents with herbal origins have been reported against this deadly disease. This study is the first to examine the cytotoxic and apoptotic effects of Urtica dioica in MDA-MB-468, human breast adenocarcinoma cells. The 3-(4,5-dimethylethiazol-2 yl)-2,5- diphenyltetrazolium (MTT) reduction and trypan-blue exclusion assay were performed in MDA-MB-468 cells as well as control cell line L929 to analyze the cytotoxic activity of the dichloromethane extract. In addition, Apoptosis induction of Urtica dioica on the MDA-MB-468 cells was assessed using TUNEL (terminal deoxy transferase (TdT)-mediated dUTP nick- end labeling) assay and DNA fragmentation analysis and real-time polymerase chain reaction (PCR). The results showed that the extract significantly inhibited cell growth and viability without inducing damage to normal control cells. Nuclei Staining in TUNEL and DNA fragments in DNA fragmentation assay and increase in the mRNA expression levels of caspase-3, caspase-9, decrease in the bcl2 and no significant change in the caspase-8 mRNA expression level, showed that the induction of apoptosis was the main mechanism of cell death that induce by Urtica dioica extract. Our results suggest that urtica dioica dichloromethane extract may contain potential bioactive compound(s) for the treatment of breast adenocarcinoma.

RAPD-PCR and real-time PCR HRM based genetic variation evaluations of Urtica dioica parts, ecotypes and evaluations of morphotypes in Turkey.

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Uzonur, Irem; Akdeniz, Gamze; Katmer, Zeynep; Ersoy, Seyda Karaman

2013-01-01

Urtica dioica is an ethnobotanically and medicinally important Complementary and Alternative Medicine (CAM) plant worldwide and in Turkey; 90 % of herbal CAM applications depend on it in Turkey. It has a wide range of habitats in nearly all continents. It is found in all three phytogeographical regions in Turkey (Euro-Siberian, Irano-Turanian, Mediterranean) with high adaptivity to heterogeneous geographies such as climate, soil types and altitudes. This fact in relation to the assessment of chemical constituents of the plant and combining with further genetic and morphological variation data can assist and enhance the works for the utility and reliability of CAM applications in effect and activity of this plant species. In this work we have made some preliminary experiments with novel approaches to reveal the ecotypes and genetic variation of mighty ecotypes of Urtica dioica from different phytogeographical regions of Turkey (Euro-Siberian and Mediterranean). The ecotypes have heterogeneity in both its parts (leaf, stem, root) as revealed by Random Amplified Polymorphic DNA-Polymerase Chain Reaction (RAPD-PCR) using random primers and High-resolution Melt (HRM) analysis using Urtica dioica specific primers and universal chloroplast DNA (cpDNA) primers and morphological traits such as phenolic contents and antioxidant capacities of plants' leaf infusions as used in medicinal applications in Turkey. This work will contribute a lot for the development of molecular markers to detect the genetic variation and heterogeneity of Urtica dioica to further relate with expected phenotypes that are most useful and relevant in CAM applications.

The Urtica dioica Agglutinin Is a Complex Mixture of Isolectins 1

Science.gov (United States)

Van Damme, Els J. M.; Broekaert, Willem F.; Peumans, Willy J.

1988-01-01

Rhizomes of stinging nettle (Urtica dioica) contain a complex mixture of isolectins. Ion exchange chromatography with a high resolution fast protein liquid chromatography system revealed six isoforms which exhibit identical agglutination properties and carbohydrate-binding specificity and in addition have the same molecular structure and virtually identical biochemical properties. However, since the U. dioica agglutinin isolectins differ definitely with respect to their amino acid composition, it is likely that at least some of them are different polypeptides coded for by different genes. Images Fig. 3 PMID:16665952

Protective Effect of Urtica dioica L. (Urticaceae) on Morphometric and Morphologic Alterations of Seminiferous Tubules in STZ Diabetic Rats.

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Golalipour, Mohammad Jafar; Kabiri Balajadeh, Babak; Ghafari, Soraya; Azarhosh, Ramin; Khori, Vahid

2011-09-01

Urtica dioica L. has been known as a medicinal plant in the world. This study was conducted to determine the effects of the hydroalcoholic extract of Urtica dioica leaves on seminiferous tubules of diabetic rats. Animals were allocated to control, diabetic and protective groups. Treated animals received extract of U. dioica (100 mg/ kg/ day) IP for the first 5 days and STZ injection on the 6th day. After 5 weeks, testes removed and stained with H&E technique. Tubular cell disintegration, sertoli and spermatogonia cell vacuolization, and decrease in sperm concentration observed in diabetic in comparison with control and protective groups. External seminiferous tubular diameter and seminiferous epithelial height significantly reduced (Pdioica, before induction of diabetes; has protective role on seminiferous tubules alterations.

Saponins from Cephalaria aristata C. Koch

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Derya Gülcemal

2014-05-01

Full Text Available One new oleanane-type saponin, 3-O-β-D-glucopyranosyl-(1→4-β-D-xylopyranosyl-(1→3-α-L-rhamnopyranosyl-(1→2-α-L-arabinopyranosyl hederagenin 28-O-β-D-glucopyranosyl-(1→6-β-D-glucopyranosyl ester (1 was isolated from the MeOH extract of whole plant parts of Cephalaria aristata C. Koch along with three known oleanane-type saponins (2-4, 3-O- α -L-rhamnopyranosyl-(1→2- α -L-arabinopyranosyl hederagenin 28-O-( β -D-glucopyranosyl-(1→6- β -D-glucopyranosyl ester, 3-O- β -D-glucopyranosyl-(1→4- β -D-xylopyranosyl-(1→3- α -L-rhamnopyranosyl-(1→2- α -L-arabinopyranosyl hederagenin and 3-O- α -L-rhamnopyranosyl-(1→2- α -L-arabinopyranosyl hederagenin respectively, (5-7, oleanolic acid (5, β -amyrin (6 and 20 β -hydroxyursolic acid (7 and one sterol glucoside (8, 29-hydroxystigmast-5-en-3-O- β -D-glucopyranosyde. Their structures were established by the extensive use of 1D- and 2D-NMR experiments along with ESIMS and HRMS analysis.

Specific activity of radionuclides in technological processing of nettle (urtica) for food

International Nuclear Information System (INIS)

Ivanova, T.N.; Odintsov, Yu.A.; Zakharchenko, G.A.; Chernikov, S.A.

1996-01-01

Possibility of using nettle (urtica) for food in the regions, contaminated after the Chernobyl accident, is studied. Clear dependence of 137 Cs transport from the soil into the nettle is not determined even in the regions with high density of soil contamination. It is established that nettle wetting during one hour in water completely relieves it from 137 Cs. It is recommended to use the nettle as source material of biologically active substances for nutrition purposes. 6 refs

Negative evidence of Wolbachia in the predaceous mite Phytoseiulus persimilis.

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Enigl, M; Zchori-Fein, E; Schausberger, P

2005-01-01

The cytoplasmically inherited bacterium Wolbachia is widespread in arthropod species and has been repeatedly detected in the predaceous mite Phytoseiulus persimilis. Our original goal was to assess the prevalence of Wolbachia infection in P. persimilis and the potential fitness consequences for this host. To accomplish that goal, seven P. persimilis strains were obtained from Europe, Africa and the USA and reared on the phytophagous mite Tetranychus urticae as prey. After preliminary results showed that the T. urticae used was infected with Wolbachia, the minimum starvation time of the predators to prevent false positive results from undigested prey was determined. We tested DNA samples by PCR (polymerase chain reaction) after starving the predators or feeding them Wolbachia-free T. urticae for various periods. Those experiments showed that Wolbachia could not be detected after 16 h at 25 degrees C and 48 h at 20 degrees C. To verify the results of the PCR analyses, we furthermore conducted crossing experiments with antibiotic-treated and untreated individuals. No indications of Wolbachia effects were recorded. Additionally, we screened live eggs of four of the seven strains reared in our laboratory and alcohol samples of 10 other P. persimilis strains for the occurrence of Wolbachia by PCR, none of which tested positive. Synthesis of our study and previous reports suggests that infection of P. persimilis with Wolbachia is extremely rare and of minor importance. We discuss the significance of our findings for future studies on the presence of Wolbachia in predaceous arthropods.

Vulnerability and behavioral response to ultraviolet radiation in the components of a foliar mite prey-predator system

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Tachi, Fuyuki; Osakabe, Masahiro

2012-12-01

Ambient ultraviolet-B (UVB) radiation impacts plant-dwelling arthropods including herbivorous and predatory mites. However, the effects of UVB on prey-predator systems, such as that between the herbivorous spider mite and predatory phytoseiid mite, are poorly understood. A comparative study was conducted to determine the vulnerability and behavioral responses of these mites to ultraviolet (UV) radiation. First, we analyzed dose-response (cumulative irradiance-mortality) curves for the eggs of phytoseiid mites ( Neoseiulus californicus, Neoseiulus womersleyi, and Phytoseiulus persimilis) and the spider mite ( Tetranychus urticae) to UVB radiation from a UV lamp. This indicated that the phytoseiid mites were more vulnerable than the spider mite, although P. persimilis was slightly more tolerant than the other two phytoseiid mites. Second, we compared the avoidance behavior of adult female N. californicus and two spider mite species ( T. urticae, a lower leaf surface user; Panonychus citri, an upper leaf surface user) in response to solar UV and visible light. N. californicus actively avoided both types of radiation, whereas P. citri showed only minimal avoidance behavior. T. urticae actively avoided UV as well as N. californicus but exhibited a slow response to visible light as well as P. citri. Such variation in vulnerability and avoidance behavior accounts for differences in the species adaptations to solar UVB radiation. This may be the primary factor determining habitat use among these mites on host plant leaves, subsequently affecting accessibility by predators and also intraguild competition.

Preferencia alimenticia del ácaro depredador Balaustium sp. en condiciones controladas

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Muñoz Karen

2009-04-01

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Se evaluó la preferencia de presas de Balaustium sp., enemigo natural de diferentes artrópodos plaga, y el cual es nativo de la Sabana de Bogotá. En unidades experimentales construidas con foliolos de plantas de rosa se colocaron independientemente individuos de Balaustium sp. y se registró el número de presas consumidas. De esta manera se determinó la preferencia de los tres estados móviles del ácaro depredador Balaustium sp. por diferentes edades de tres presas. Las especies y edades de las presas estudiadas fueron: huevos, ninfas y adultos de Trialeurodes vaporariorum, huevos, ninfas y adultos de Tetranychus urticae, y larvas de primer y segundo instar y adultos de Frankliniella occidentalis. Los estados menos desarrollados fueron preferidos, aunque se observó que los adultos del depredador tienen gran habilidad para consumir adultos de T. vaporariorum. La presa preferida por las larvas de Balaustium sp. fue los huevos de T. urticae con una proporción de consumo de 0,54 de los huevos que se ofrecieron de esta presa; las deutoninfas del depredador eligieron huevos de T. vaporariorum (0,537 o de T. urticae (0,497 y los adultos de Balaustium sp. prefrieron los huevos de T. vaporariorum (0,588.

Urtica dioica pollen allergy: Clinical, biological, and allergomics analysis.

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Tiotiu, Angelica; Brazdova, Andrea; Longé, Cyril; Gallet, Patrice; Morisset, Martine; Leduc, Virginie; Hilger, Christiane; Broussard, Cédric; Couderc, Rémy; Sutra, Jean-Pierre; Sénéchal, Hélène; Poncet, Pascal

2016-11-01

The most emblematic members of Urticaceae at allergic risk level are wall pellitories (Parietaria), whereas nettle (Urtica) pollen is considered as poorly allergenic. No allergen from nettle pollen has yet been characterized, whereas 4 are listed for Parietaria pollen by the International Union of Immunological Societies. Clinical and biological profiles of 2 adult men who developed symptoms against nettle pollen and/or leaves were studied. To characterize the allergic reaction and identify the potential nettle pollen sensitizing allergens. IgE-mediated reaction to nettle pollen extract was evaluated by skin prick test, immunoassay, nasal provocation, and basophil activation test. To characterize specific nettle pollen allergens, an allergomic (IgE immunoproteomic) analysis was performed combining 1- and 2-dimensional electrophoresis, IgE immunoblots of nettle pollen extract, identification of allergens by mass spectrometry, and database queries. The results of biological and immunochemical analyses revealed that the allergic rhinitis was due to Urtica dioica pollen in both patients. The allergomic analysis of nettle pollen extract allowed the characterization of 4 basic protein allergens: a thaumatin-like protein (osmotin) with a relative molecular mass of 27 to 29 kDa, a pectinesterase (relative molecular mass, 40 kDa), and 2 other basic proteins with relative molecular masses of 14 to 16 kDa and 43 kDa. There is no or only very weak allergen associations between pellitory and nettle pollen. Exposure to nettle pollen can be responsible of allergic symptoms, and several allergens were characterized. Unravelling the allergens of this underestimated allergy might help to improve diagnosis and care for patients, to predict cross-reactivities and design adapted specific immunotherapy. Copyright © 2016 American College of Allergy, Asthma & Immunology. Published by Elsevier Inc. All rights reserved.

Methyl salicylate production in tomato affects biotic interactions.

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Ament, Kai; Krasikov, Vladimir; Allmann, Silke; Rep, Martijn; Takken, Frank L W; Schuurink, Robert C

2010-04-01

The role of methyl salicylate (MeSA) production was studied in indirect and direct defence responses of tomato (Solanum lycopersicum) to the spider mite Tetranychus urticae and the root-invading fungus Fusarium oxysporum f. sp. lycopersici, respectively. To this end, we silenced the tomato gene encoding salicylic acid methyl transferase (SAMT). Silencing of SAMT led to a major reduction in SAMT expression and MeSA emission upon herbivory by spider mites, without affecting the induced emission of other volatiles (terpenoids). The predatory mite Phytoseiulus persimilis, which preys on T. urticae, could not discriminate between infested and non-infested SAMT-silenced lines, as it could for wild-type tomato plants. Moreover, when given the choice between infested SAMT-silenced and infested wild-type plants, they preferred the latter. These findings are supportive of a major role for MeSA in this indirect defence response of tomato. SAMT-silenced tomato plants were less susceptible to a virulent strain of F. oxysporum f. sp. lycopersici, indicating that the direct defense responses in the roots are also affected in these plants. Our studies show that the conversion of SA to MeSA can affect both direct and indirect plant defence responses.

Criterios para la liberación de Phytoseiulus persimilis Athias Henriot (Parasitiformes: Phytoseiidae en cultivo de rosa

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Hilarión Alejandra

2008-04-01

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Phytoseiulus persimilis ha sido utilizado en programas de manejo integrado de plagas como alternativa al uso de acaricidas para el manejo de Tetranychus urticae. Los daños ocasionados por T. urticae generan un costo de manejo cercano a los 4.500 dólares por hectárea, esta cifra corresponde aproximadamente al 30% del costo de los plaguicidas (Ceniflores, 2008. La implementación de esta estrategia de manejo debe considerar criterios de liberación basados en los niveles de población de T. urticae del cultivo, estimados a partir de una metodología de muestreo apropiada. En el presente trabajo, se propuso una metodología para estimar el nivel de infestación de T. urticae, para conocer la cantidad de P. persimilis a liberar en el cultivo de rosa y se evaluó la efectividad del control ejercido por P. persimilis. En el área experimental se tomaron 81 cuadros, en cada uno de ellos se muestrearon al azar tres plantas de rosa y se contó el número de individuos en tres hojas de cada tercio de la planta. Así mismo, se determinó el número óptimo de muestras para un muestreo bietápico. Se tuvo en cuenta la respuesta funcional como criterio de liberación de P. persimilis. La población de T. urticae estimada después de la liberación se dividió entre la población previa a la liberación para obtener un índice de control, el cual se comparó entre las estrategias de manejo. Con el control biológico se obtuvo una mayor reducción de la población de la plaga y una menor fluctuación de esta a través del tiempo.

Lead uptake, tolerance, and accumulation exhibited by the plants Urtica dioica and Sedum spectabile in contaminated soil without additives

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Grubor Milena

2008-01-01

Full Text Available Specimens of Urtica dioica and Sedum spectabile collected from plants growing at uncontaminated sites were transplanted in Pb-contaminated soil without additives (EDTA, HEDTA to identify their natural potential for hyper-tolerance and hyperaccumulation of lead. The total content of Pb in the plants was determined by atomic spectroscopy. Our research showed that the concentrated toxic levels of lead (Pb in Sedum spectabile and Urtica dioica were about 100 or more times higher than those of non-accumulator plants. It can be concluded that these plants have a high natural potential for hypertolerance and hyperaccumulation of lead, since they can hyperaccumulate it without addition of any chelating compounds (EDTA, HEDTA to enhance lead uptake. This makes them very promising plants for use in phytoremediation of Pb-contaminated sites.

Jurij Koch – nové interpretace lužickosrbské prózy. Od socrealismu k jeho destrukci

Czech Academy of Sciences Publication Activity Database

Ulbrechtová, Helena

2009-01-01

Roč. 13, Suppl. 2 (2009), s. 173-188 ISSN 1803-5663 Institutional research plan: CEZ:AV0Z90920516 Keywords : socialist realism * Sorbian literature * Koch, Jurij, 1936- Subject RIV: AJ - Letters, Mass-media, Audiovision

Antalya İlinde Portakal Bahçelerinde Gözlenen Önemli Zararlı ve Yararlı Böcek Popülasyonları

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Vildan GÖL

2016-06-01

Full Text Available Bu çalışmada, 2014 yılında, Antalya ilinde bulunan iki portakal bahçesinde önemli zararlı ve yararlı böcek popülasyonları belirlenmiştir. Bahçelerde ağırlıklı olarak portakal bulunması nedeniyle örneklemeler de bu tür üzerinde yapılmıştır. Çalışma süresince zararlılara karşı herhangi bir mücadele yöntemi uygulanmamıştır. Çalışmada örneklerin toplanması için gözle kontrol yöntemi, yaprak, sürgün, meyve örnekleme yöntemi, darbe ve tuzakla yakalama yöntemi kullanılmıştır. Çalışma sonucunda zararlı türler olarak Tetranychus urticae (Koch (Acarina: Tetranychidae, Empoasca decipiens (Paoli, Asymmetrasca decedens (Paoli (Hemiptera: Cicadellidae, Dialeurodes citri (Ashmead, Aleurothrixus floccosus (Maskell (Hem.: Aleyrodidae, Aphis craccivora (Koch (Hem.: Aphididae, Icerya purchasi Maskell (Hem.: Margarodidae, Coccus hesperidum (Linnaeus, Ceroplastes floridensis (Comstock (Hem.: Coccidae, Aonidiella aurantii (Maskell, Aonidiella citrina (Coquillet, Parlatoria pergandii (Comstock (Hem.: Diaspididae, Planococcus citri (Risso (Hem.: Pseudococcidae, Ceratitis capitata (Wiedemann (Diptera: Tephritidae ve Phyllocnistis citrella (Stainton (Lepidoptera: Gracillaridae saptanmıştır. Bunlardan E. decipiens (Paoli, A. decedens (Paoli, A. floccosus (Maskell, A. aurantii (Maskell ve Parlatoria pergandii (Comstock en yaygın türler olarak belirlenmiştir. Ayrıca 2 takıma bağlı 7 avcı ve asalak tür saptanmıştır. Bu türler: Chrysoperla carnea (Stephens (Neuroptera: Chrysopidae, Coccinella septempunctata L., Chilocorus bipustulatus L., Rhyzobius lophantae (Blaisdell, Oenopia conglobata (L. (Coleoptera: Coccinellidae, Aphytis melinus DeBach ve Comperiella bifasciata (Coleoptera: Aphelinidae’ dır. Çalışmada ayrıca zararlı iki cicadellid türü ile A. floccosus, A. aurantii, P. pergandii, C. capitata‘nın ve doğal düşmanlardan C. carnea’nın, coccinellidlerin, A. melinus ve E. citrina�

Gynaecomastia in a man and hyperoestrogenism in a woman due to ingestion of nettle (Urtica dioica).

Science.gov (United States)

Sahin, Mustafa; Yilmaz, Hamiyet; Gursoy, Alptekin; Demirel, Asli Nar; Tutuncu, Neslihan Bascil; Guvener, Nilgun Demirag

2007-11-09

Nettle (Urtica dioica) is commonly sold as a herbal tea in Turkey. We report a case of gynaecomastia in a man (in which the only aetiologic factor identified was nettle tea consumption) and a case of galactorrhoea in a woman (in which the only aetiologic factor identified was also nettle tea ingestion).

Native Phytoremediation Potential of Urtica dioica for Removal of PCBs and Heavy Metals Can Be Improved by Genetic Manipulations Using Constitutive CaMV 35S Promoter.

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Jitka Viktorova

Full Text Available Although stinging nettle (Urtica dioica has been shown to reduce HM (heavy metal content in soil, its wider phytoremediation potential has been neglected. Urtica dioica was cultivated in soils contaminated with HMs or polychlorinated biphenyls (PCBs. After four months, up to 33% of the less chlorinated biphenyls and 8% of HMs (Zn, Pb, Cd had been removed. Bacteria were isolated from the plant tissue, with the endophytic bacteria Bacillus shackletonii and Streptomyces badius shown to have the most significant effect. These bacteria demonstrated not only benefits for plant growth, but also extreme tolerance to As, Zn and Pb. Despite these results, the native phytoremediation potential of nettles could be improved by biotechnologies. Transient expression was used to investigate the functionality of the most common constitutive promoter, CaMV 35S in Urtica dioica. This showed the expression of the CUP and bphC transgenes. Collectively, our findings suggest that remediation by stinging nettle could have a much wider range of applications than previously thought.

Native Phytoremediation Potential of Urtica dioica for Removal of PCBs and Heavy Metals Can Be Improved by Genetic Manipulations Using Constitutive CaMV 35S Promoter.

Science.gov (United States)

Viktorova, Jitka; Jandova, Zuzana; Madlenakova, Michaela; Prouzova, Petra; Bartunek, Vilem; Vrchotova, Blanka; Lovecka, Petra; Musilova, Lucie; Macek, Tomas

2016-01-01

Although stinging nettle (Urtica dioica) has been shown to reduce HM (heavy metal) content in soil, its wider phytoremediation potential has been neglected. Urtica dioica was cultivated in soils contaminated with HMs or polychlorinated biphenyls (PCBs). After four months, up to 33% of the less chlorinated biphenyls and 8% of HMs (Zn, Pb, Cd) had been removed. Bacteria were isolated from the plant tissue, with the endophytic bacteria Bacillus shackletonii and Streptomyces badius shown to have the most significant effect. These bacteria demonstrated not only benefits for plant growth, but also extreme tolerance to As, Zn and Pb. Despite these results, the native phytoremediation potential of nettles could be improved by biotechnologies. Transient expression was used to investigate the functionality of the most common constitutive promoter, CaMV 35S in Urtica dioica. This showed the expression of the CUP and bphC transgenes. Collectively, our findings suggest that remediation by stinging nettle could have a much wider range of applications than previously thought.

Influence of temperature and brewing time of nettle (Urtica dioica L.) infusions on vitamin C content

Science.gov (United States)

Wolska, Jolanta; Czop, Michał; Jakubczyk, Karolina; Janda, Katarzyna

Stinging nettle (Urtica dioica L.) can be found in temperate climate zones of Europe, Africa and America Nettle may be a source of nutritional ingredients, mineral salts, vitamins and antioxidants. The aim of the study was to determine the effect of temperature and brewing time Urtica dioica L. infusions from different parts of this plant on vitamin C (ascorbic acid) content. Infusions of nettle leaf, stem and root were prepared at room temperature, 50°C, 60°C, 70°C and 80°C for 10 minutes. Leaf infusions were also brewed for 5, 10, 15 and 20 minutes at initial water temperature of 60°C. The amount of vitamin C was determined by the spectrophotometric method. The best temperature of brewing nettle infusions, in terms of vitamin C concentration, is between 50 °C and 60 °C as it is sufficient to extract the substance, yet not high enough to destroy it. The optimal time of brewing appeared to be 10 minutes as the prolonged exposure to high temperature appeared to be detrimental for ascorbic acid as well.

Opositsioon veeretab Villu Reiljani kaudu vastutuse peaministrile / Tuuli Koch, Kärt Anvelt, Rasmus Kagge

Index Scriptorium Estoniae

Koch, Tuuli

2006-01-01

Ilmunud ka: Postimees : na russkom jazõke 9. veebr. lk. 4. Opositsioon nõudis Riigikogu infotunnis keskkonnaminister Villu Reiljanilt ja siseminister Kalle Laanetilt reostusega seotud küsimustele vastuseid. Valitsuse vastasleeri poliitikud oletavad, et kui peaminister Andrus Ansip jätab Reiljani ametisse, on poliitilise vastutuse kord peaministri enda käes. Kommenteerib peaminister Andrus Ansip. Vt. samas: Tuuli Koch. Laanet ja Reiljan ei taha vastutust enesele võtta; Ansipi soolo

Unaffectedness and Rare Eurythmics: Carl Koch, Jean Renoir, Luchino Visconti and the Production of Tosca (1939/41)

NARCIS (Netherlands)

Blom, I.L.

2017-01-01

Tosca (1941) is a curious and intriguing case in film history. It was originally begun by French director Jean Renoir, but finished by his German screenwriter-turned-director Carl Koch. Koch’s wife Lotte Reiniger and the young Luchino Visconti contributed to the film, while its producer was the

AROMA PROFILE AND ANTIMICROBIAL PROPERTIES OF ALCOHOLIC AND AQUEOUS EXTRACTS FROM ROOT, LEAF AND STALK OF NETTLE (Urtica dioica L.

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Razzagh Mahmoudi

2014-12-01

Full Text Available Medicinal plant can be considered as a great source of new antimicrobial agents due to their enormous therapeutic potential and limited side effects. Nettle (Urtica dioica L. is a widespread and common medicinal plant widely used in traditional medicine. The present study investigates the antimicrobial potency of alcoholic and aqueous extracts of Urtica dioica on some gram positive and negative bacteria and also a particular type of fungi and analyzes the extracts to find the active ingredients by gas chromatography-mass spectroscopy (GC-MS method. Results from disc diffusion assay indicated that water extract of root, leaf and stalk had the highest antimicrobial activity respectively and caused significant inhibition zones in P. vulgaris, L. monocytogenes and K. pneumoniae cultures. Antimicrobial efficacy of ethanol extracts was higher in root extract which caused high growth inhibition zones in P. vulgaris, K. pneumoniae and S. aureus cultures. MBC and MIC experiments of the ethanol extract illustrated that the most powerful antimicrobial effect was related to the stem organ extract on K. pnuomonae and S. aureus bacteria. Highest level of antibacterial effects in root can be due to its higher concentration of contents compared to other organs. Based on these results it can be suggested that Urtica dioica and its water and ethanol extracts have noticeable antimicrobial effects against gram negative, positive and Candida albicans fungi that may be applicable as a prophylactic or therpeutic antimicrobial agent in both human and animals.

The predatory mite Phytoseiulus persimilis adjusts patch-leaving to own and progeny prey needs.

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Vanas, V; Enigl, M; Walzer, A; Schausberger, P

2006-01-01

Integration of optimal foraging and optimal oviposition theories suggests that predator females should adjust patch leaving to own and progeny prey needs to maximize current and future reproductive success. We tested this hypothesis in the predatory mite Phytoseiulus persimilis and its patchily distributed prey, the two-spotted spider mite Tetranychus urticae. In three separate experiments we assessed (1) the minimum number of prey needed to complete juvenile development, (2) the minimum number of prey needed to produce an egg, and (3) the ratio between eggs laid and spider mites left when a gravid P. persimilis female leaves a patch. Experiments (1) and (2) were the pre-requirements to assess the fitness costs associated with staying or leaving a prey patch. Immature P. persimilis needed at least 7 and on average 14+/-3.6 (SD) T. urticae eggs to reach adulthood. Gravid females needed at least 5 and on average 8.5+/-3.1 (SD) T. urticae eggs to produce an egg. Most females left the initial patch before spider mite extinction, leaving prey for progeny to develop to adulthood. Females placed in a low density patch left 5.6+/-6.1 (SD) eggs per egg laid, whereas those placed in a high density patch left 15.8+/-13.7 (SD) eggs per egg laid. The three experiments in concert suggest that gravid P. persimilis females are able to balance the trade off between optimal foraging and optimal oviposition and adjust patch-leaving to own and progeny prey needs.

The granule cell density of the dentate gyrus following administration of Urtica dioica extract to young diabetic rats.

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Fazeli, S A; Gharravi, A M; Ghafari, S; Jahanshahi, M; Golalipour, M J

2008-08-01

Urtica dioica L. Stinging nettle has long been known worldwide as a medicinal plant. To study the benefits of the nettle in diabetic encephalopathy, the granule cell density of the dentate gyrus of diabetic rats was studied following administration of Urtica dioica extract. A total of 24 male albino Wistar rats were allocated equally to normal, diabetic, preventive and treatment groups. Hyperglycaemia was induced by streptozotocin (80 mg/kg) in the animals of the diabetic and treatment groups. One week after injection of the streptozotocin the animals in the treatment group received a hydroalcoholic extract of Urtica dioica (100 mg/kg/day) for 4 weeks intraperitoneally. The rats of the preventive group received hydroalcoholic extract of U. dioica (100 mg/kg/day) IP for the first 5 days and an injection of streptozotocin (80 mg/kg) on the 6th day. After 5 weeks of study all the rats were sacrificed and coronal sections were taken from the dorsal hippocampal formation of the right cerebral hemispheres and stained with cresyl violet. The area densities of the granule cells were measured and compared in the four groups. The density was lower in the diabetic rats compared with the controls (p > 0.05). The preventive group showed lower cell density than the controls (p > 0.05). The densities in the treated rats were higher than in the diabetic rats (p > 0.05). Furthermore, the control and treated rats showed similar densities (p > 0.05). It seems that U. dioica extract can help compensate for granule cell loss in the diabetic rat dentate gyrus, which can ameliorate cognitive impairment in diabetes. However, preventive use of the extract showed no significant benefit.

EN EL CENTENARIO DEL DESCUBRIMIENTO DEL MYCOBACTERIUM TUBERCULOSIS POR ROBERTO KOCH. 24 DE MARZO DE 1982

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Gilberto Rueda Pérez

1982-12-01

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Hace exactamente 100 años, señores académicos, Roberto Koch presentó en concisa, lacónica y podríamos decir perfecta comunicación, a la Sociedad de Fisiología de Berlín, la demostración de que la TBC tenía como causa única la proliferación en el organismo vivo, del germen denominado por él Mycobacterium Tuberculosis.

Esta comunicación que hoy conmemoramos, cambió el curso de la microbiología, y sentó las bases para el desarrollo posterior del tratamiento etiológico de las enfermedades infecciosas. Años más tarde, Koch recibiría el máximo galardón otorgado por Nobel a los grandes benefactores de la humanidad, por este descubrimiento. Sería glorificado por sus
contemporáneos y por quienes posteriormente hemos tenido el privilegio de ejercer la medicina en el mundo civilizado, así como por quienes padecieron y padecen aún el terrible mal, al ver cercana su curación gracias a los descubrimientos recientes que han permitido derrotar al más temible enemigo de la patología humana: el Bacilo puesto en evidencia
por este retraído sabio alemán.

Pero no todo fue gloria y renombre en la vida de Roberto Koch. Vale la pena rememorar a grandes rasgos en este Centenario y ante esta Academia de Medicina Colombiana, algunos de los hechos sobresalientes de la vida de este hombre excepcional, que le dio luz en su época y le sigue dando a la ciencia en general, y que sentó premisas que siguen vigentes en nuestros días a través del postulado que lleva su nombre, ineludibles para quienes quieren demostrar científicamente hechos bacteriológicos.

Nace el 11 de diciembre de 1843 en la pequeña población de Klausthal en Hanover, y allí transcurre su primera juventud provinciana y sencilla para luego viajar a Gotinga, en cuya universidad estudia medicina, destacándose siempre por su dedicación y método en las asignaturas, recibiendo su doctorado en 1886, a los 23 años, bajo la tutela del Profesor

Heavy metal pollution affects consumption and reproduction of the landsnail Cepaea Nemoralis fed on naturally polluted Urtica dioica leaves.

NARCIS (Netherlands)

Notten, M.J.M.; Oosthoek, A.; Rozema, J.; Aerts, R.

2006-01-01

This study is one of the very first that investigates the effects of heavy metal pollution on food consumption and reproduction of terrestrial snails under semi-realistic field conditions. Two experiments were carried out using snails (Cepaea nemoralis) and food (Urtica dioica leaves) from different

Protection of Ischemic and Reperfused Rat Heart by Aqueous Extract of Urtica Dioica

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D Shackebaei

2010-09-01

Full Text Available Background: Urtica dioica (U.D has widely been used in traditional medicine for its hypotensive and vasodilatory effects. The objective of this study was to clarify the effects of aqueous extract of Urtica dioica on isolated ischemia- reperfused heart.Methods: The heart of male wistar rats were isolated and perfused according to langendorff method. In the control group (n = 13 the hearts were subjected to three steps of stabilization (30 min, normothermic global ischemia (40 min and reperfusion (45 min. In addition, before and after ischemia, the aqueous extract of U.D (200 mg/ml was added to perfusion solution in the test group (n=14. Different cardiac variables including left ventricular pressure, heart rate and coronary flow were measured and rate pressure product was calculated.Results: Results showed that left ventricular pressure (59.11±4.7 and rate pressure product (13680±1136 in 45th minute of reperfusion in the test group were significantly (P=0.0187 and 0.0321 respectively greater than the control group (39.1±6.0, 9480±1480 respectively. These findings indicated decreased cardiac damage following ischemia in the test group, compared with that of control group.Conclusion: Results of the present study showed that the aqueous extract of U.D, increased the tolerance of isolated rat hearts against ischemic damage. This effect can be explained by potent antioxidant activity of the U.D extract, suggesting its clinical use in ischemic heart disease.

Efeito do manejo de plantas daninhas sobre Neoseiulus californicus (Acari:Phytoseiidae em pomar de macieira Effect of weed management on Neoseiulus californicus (Acari:Phytoseiidae in apple orchard

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Lino Bittencourt Monteiro

2002-12-01

Full Text Available Avaliou-se a influência do manejo de plantas daninhas sobre o deslocamento de ácaros tetraniquídeos (Panonychus ulmi e Tetranychus urticae e do ácaro predador Neoseiulus californicus em um pomar de macieira 'Gala', onde foi implantado o controle biológico do ácaro vermelho, P. ulmi, por meio de liberações massais de N. californicus. As parcelas tiveram as plantas daninhas manejadas de três formas: sem manejo, com roçadas manuais e com herbicidas. As populações de ácaros foram avaliadas sobre as plantas daninhas, Plantago tormentosa e Erigeron sp, e sobre as folhas de macieira. As maiores populações de N. californicus foram observadas nas parcelas onde os manejos proporcionaram desenvolvimento de plantas daninhas na linha de plantio. Na parcela manejada com herbicida, houve maior população de ácaros tetraniquídeos sobre as macieiras, provavelmente, devido ao reduzido número de N. californicus. P. tormentosa foi o hospedeiro preferencial do ácaro predador. Concluiu-se que o manejo de plantas daninhas, na linha de plantio das macieiras, assume um importante papel no equilíbrio entre as populações de ácaros.The influence of weed management on tetranychid mites (Panonychus ulmi and Tetranychus urticae and phytoseids movement was evaluated. Neoseiulus californicus populations were released in an apple orchard for biological control of tetranychid mites. Three kinds of weed management were used: no weed control at all, manual control and control with herbicide. The mites were evaluated in Plantago tormentosa, Erigeron sp, and apple tree leaves. The highest population of N. californicus was observed where weed was not controlled. Tetranychid mites populations were abundant on apple trees when herbicide was used, probably due to the low population of N. californicus. P. tormentosa was the preferred host of phytoseids. The conclusion was that weed management plays an important role in the regulation of mite species in apple

Feeding Behaviour on Host Plants May Influence Potential Exposure to Bt Maize Pollen of Aglais Urticae Larvae (Lepidoptera, Nymphalidae).

Science.gov (United States)

Lang, Andreas; Otto, Mathias

2015-08-31

Non-target butterfly larvae may be harmed by feeding on host plants dusted with Bt maize pollen. Feeding patterns of larvae and their utilization of host plants can affect the adverse Bt impact because the maize pollen is distributed unequally on the plant. In a field study, we investigated the feeding of larvae of the Small Tortoiseshell, Aglais urticae, on nettles, Urtica dioica. Young larvae used smaller host plants than older larvae. In general, the position of the larvae was in the top part of the host plant, but older larvae showed a broader vertical distribution on the nettles. Leaf blades and leaf tips were the plant parts most often consumed. Leaf veins were consumed but midribs were fed on to a lesser extent than other plant veins, particularly by young larvae. The feeding behavior of the larvae may increase possible exposure to Bt maize pollen because pollen densities are expected to be higher on the top parts and along leaf veins of nettles.

Feeding Behaviour on Host Plants May Influence Potential Exposure to Bt Maize Pollen of Aglais Urticae Larvae (Lepidoptera, Nymphalidae

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Andreas Lang

2015-08-01

Full Text Available Non-target butterfly larvae may be harmed by feeding on host plants dusted with Bt maize pollen. Feeding patterns of larvae and their utilization of host plants can affect the adverse Bt impact because the maize pollen is distributed unequally on the plant. In a field study, we investigated the feeding of larvae of the Small Tortoiseshell, Aglais urticae, on nettles, Urtica dioica. Young larvae used smaller host plants than older larvae. In general, the position of the larvae was in the top part of the host plant, but older larvae showed a broader vertical distribution on the nettles. Leaf blades and leaf tips were the plant parts most often consumed. Leaf veins were consumed but midribs were fed on to a lesser extent than other plant veins, particularly by young larvae. The feeding behavior of the larvae may increase possible exposure to Bt maize pollen because pollen densities are expected to be higher on the top parts and along leaf veins of nettles.

HvPap-1 C1A Protease Participates Differentially in the Barley Response to a Pathogen and an Herbivore

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Mercedes Diaz-Mendoza

2017-09-01

Full Text Available Co-evolutionary processes in plant–pathogen/herbivore systems indicate that protease inhibitors have a particular value in biotic interactions. However, little is known about the defensive role of their targets, the plant proteases. C1A cysteine proteases are the most abundant enzymes responsible for the proteolytic activity during different processes like germination, development and senescence in plants. To identify and characterize C1A cysteine proteases of barley with a potential role in defense, mRNA and protein expression patterns were analyzed in response to biotics stresses. A barley cysteine protease, HvPap-1, previously related to abiotic stresses and grain germination, was particularly induced by flagellin or chitosan elicitation, and biotic stresses such as the phytopathogenic fungus Magnaporthe oryzae or the phytophagous mite Tetranychus urticae. To elucidate the in vivo participation of this enzyme in defense, transformed barley plants overexpressing or silencing HvPap-1 encoding gene were subjected to M. oryzae infection or T. urticae infestation. Whereas overexpressing plants were less susceptible to the fungus than silencing plants, the opposite behavior occurred to the mite. This unexpected result highlights the complexity of the regulatory events leading to the response to a particular biotic stress.

Antiproliferative effect on human prostate cancer cells by a stinging nettle root (Urtica dioica) extract.

Science.gov (United States)

Konrad, L; Müller, H H; Lenz, C; Laubinger, H; Aumüller, G; Lichius, J J

2000-02-01

In the present study the activity of a 20% methanolic extract of stinging nettle roots (Urtica dioica L., Urticaceae) on the proliferative activity of human prostatic epithelial (LNCaP) and stromal (hPCPs) cells was evaluated using a colorimetric assay. A concentration-dependent and significant (p nettle roots observed both in an in vivo model and in an in vitro system clearly indicates a biologically relevant effect of compounds present in the extract.

Urticaria due to Urtica dioica in a neonate.

Science.gov (United States)

Uslu, Sinan; Bulbul, Ali; Diler, Betul; Bas, Evrim Kiray; Nuhoglu, Asiye

2011-03-01

Urticaria is one of the most common dermatoses during the childhood, but it is very rare in the neonates. A 17-day-old infant with a generalized urticaria was admitted to our pediatric emergency unit. The mother of the infant reported having applied water boiled with stinging nettle (Urtica dioica) onto her nipples twice a day (before and after each breastfeeding) for 2 days in order to heal her nipple cracks. Serum total immunoglobulin E (IgE) and specific IgE levels for stinging nettle were high in the infant and the mother. The rashes began to regress within the first day of the hospitalization and disappeared completely on the second day without treatment. The skin prick test with the water boiled with stinging nettle was positive for the infant with significant induration, but not for the mother. Conclusion Reporting the first urticaria case in newborns due to stinging nettle, the authors suggest that breastfeeding mothers should always consult a physician before using skincare products.

Ocorrência de Amblyomma fuscum Neumann, 1899 e Amblyomma humerale Koch, 1844 (Acari: Ixodidae em Bufo arenalis no estado de São Paulo, Brasil Occurence of Amblyomma fuscum Neumann, 1899 and Amblyomma humerale Koch, 1844 (Acari: Ixodidae in Bufo arenalis in the state of São Paulo, Brazil

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Afonso Lodovico Sinkoc

1997-06-01

Full Text Available O objetivo deste trabalho é relatar a ocorrência do parasitismo monoespecífico de A. fuscum NEUMANN, 1899 e A. humerale KOCH, 1844 em sapos (Bufo arenalis no Município de Rosana, Estado de São Paulo, Brasil. Este relato caracteriza um novo hospedeiro e uma nova localização geográfica para estas duas espécies de carrapatos.The objective of this work is to describe the occurence of the monoespecific parasitism of A. fuscum NEUMANN, 1899 and A. humerale KOCH, 1844 in toads (Bufo arenalis from the County of Rosana, State of São Paulo, Brazil. This is the description of a new host and new geographic site for those two species.

The inhibiting effects of Urtica dioica root extracts on experimentally induced prostatic hyperplasia in the mouse.

Science.gov (United States)

Lichius, J J; Muth, C

1997-08-01

Extracts of stinging nettle roots (Urtica dioica L. Urticaceae) are used in the treatment of benign prostatic hyperplasia (BPH). We established a BPH-model by directly implanting an urogenital sinus (UGS) into the ventral prostate gland of an adult mouse. Five differently prepared stinging nettle root extracts were tested in this model. The 20% methanolic extract was the most effective with a 51.4% inhibition of induced growth.

Influence of long-term exposure to simulated acid rain on development, reproduction and acaricide susceptibility of the carmine spider mite, Tetranychus cinnabarinus

OpenAIRE

Wang, Jin-Jun; Zhang, Jian-Ping; He, Lin; Zhao, Zhi-Mo

2006-01-01

Development, reproduction and acaricide susceptibility of Tetranychus cinnabarinus (Boisduvals) (Acari: Tetranychidae) were investigated after long-term (about 40 generations) exposure to various levels of acid rain; pH 2.5, 3.0, 4.0, and 5.6. Deionized water (pH 6.8) served as a control. The mites were reared on eggplant leaves at 28?C, 80%RH and a photoperiod of 14:10 (L:D) in the laboratory. The results showed that the duration of the immature stage was significantly affected by acid rain ...

Inhibitory effects of Urtica dioica L. root on electrophysiological properties of isolated rabbit atrioventricular node

OpenAIRE

A. Enayati; V. Khori*; M. Azadbakhat; M. Zahedi

2017-01-01

Background and objectives: The ideal drug for treatment of a wide range of supraventricular arrhythmia hasn't yet been developed. Previous studies have shown antihypertensive and negative inotropic effects of the Urtica dioica L. (nettle). Therefore, the aim of present study is to determine the rate dependent inhibitory effects of ethanol extract of nettle root and investigate the role of adrenoceptors in the anti-arrhythmic mechanism of nettle on the isolated rabbit atrio-ventricular node. M...

Mineral Properties and Dietary Value of Raw and Processed Stinging Nettle (Urtica dioica L.)

OpenAIRE

Rutto, Laban K.; Xu, Yixiang; Ramirez, Elizabeth; Brandt, Michael

2013-01-01

Stinging nettle (Urtica dioica L.) has a long history of usage and is currently receiving attention as a source of fiber and alternative medicine. In many cultures, nettle is also eaten as a leafy vegetable. In this study, we focused on nettle yield (edible portion) and processing effects on nutritive and dietary properties. Actively growing shoots were harvested from field plots and leaves separated from stems. Leaf portions (200 g) were washed and processed by blanching (1 min at 96–98°C) o...

PRODUCT NEEM AZAL T/S - BROAD-SPECTRUM PHYPOPESTICIDE FOR CONTROL OF PESTS ON VEGETABLE CROPS

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Vinelina Yankova

2016-09-01

Full Text Available Experiments for determination of the effectiveness of product Neem Azal T/S (a. i. azadirachtin were conducted at a concentration of 0,3% against some major pests in vegetable crops grown in greenhouses at the Maritsa Vegetable Crops research Institute, Plovdiv during the period 2010-2016. It was established very good insecticidal and acaricidal action of phytopesticide against: cotton aphid (Aphis gossypii Glov.; green peach aphid (Myzus persicae Sulz.; western flower trips (Frankliniella occidentalis Perg.; cotton bollworm (Helicoverpa armigera Hubn.; tomato borer (Tuta absoluta Meyrick and two-spotted spider mite (Tetranichus urticae Koch.. This product is a successful alternative to using chemical insecticides and acaricides.

Induced plant-defenses suppress herbivore reproduction but also constrain predation of their offspring.

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Ataide, Livia M S; Pappas, Maria L; Schimmel, Bernardus C J; Lopez-Orenes, Antonio; Alba, Juan M; Duarte, Marcus V A; Pallini, Angelo; Schuurink, Robert C; Kant, Merijn R

2016-11-01

Inducible anti-herbivore defenses in plants are predominantly regulated by jasmonic acid (JA). On tomato plants, most genotypes of the herbivorous generalist spider mite Tetranychus urticae induce JA defenses and perform poorly on it, whereas the Solanaceae specialist Tetranychus evansi, who suppresses JA defenses, performs well on it. We asked to which extent these spider mites and the predatory mite Phytoseiulus longipes preying on these spider mites eggs are affected by induced JA-defenses. By artificially inducing the JA-response of the tomato JA-biosynthesis mutant def-1 using exogenous JA and isoleucine (Ile), we first established the relationship between endogenous JA-Ile-levels and the reproductive performance of spider mites. For both mite species we observed that they produced more eggs when levels of JA-Ile were low. Subsequently, we allowed predatory mites to prey on spider mite-eggs derived from wild-type tomato plants, def-1 and JA-Ile-treated def-1 and observed that they preferred, and consumed more, eggs produced on tomato plants with weak JA defenses. However, predatory mite oviposition was similar across treatments. Our results show that induced JA-responses negatively affect spider mite performance, but positively affect the survival of their offspring by constraining egg-predation. Copyright © 2016 The Authors. Published by Elsevier Ireland Ltd.. All rights reserved.

Evaluation of antioxidant properties, elemental and phenolic contents composition of wild nettle (Urtica dioica L.) from Tunceli in Turkey.

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Yildirim, N C; Turkoglu, S; Ince, O K; Ince, M

2013-11-03

Wild nettle (Urtica dioica L.) types were sampled from different geographical regions in Tunceli (Turkey) to determine their mineral, vitamin, phenolic contents and their antioxidant properties. The total phenol varied from 37.419 ± 0.380 to 19.182 ± 1.00 mg of GAEs g(-1) of dry nettle. The highest radical scavenging effect was observed in Mazgirt parting of the ways 7.5 km with 33.70 ± 0.849 mg mL(-1). The highest reducing power was observed in the nettles from Mazgirt parting of the ways 7.5 km. Among the various macronutrients estimated in the plant samples, potassium was present in the highest quantity followed by calcium and phosphate. Kaempferol and resveratrol were not determined in some nettle samples but rutin levels were determined in all samples. Vitamin A concentrations were ranged between 13.64 ± 1.90 and 5.74 ± 1.00 (mg kg(-1) dry weight). These results show that Urtica dioica L. collected from Tunceli in Turkey could be considered as a natural alternative source for food, pharmacology and medicine sectors.

Ocorrência do ácaro vermelho europeu Panonychus ulmi (Koch (Tetranychidae associado à cultura da videira no Rio Grande do Sul, Brasil European red spider mite Panonychus ulmi (Koch (Tetranychidae occurrence of vineyards in Rio Grande do Sul, Brazil

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Noeli Juarez Ferla

2008-09-01

Full Text Available Neste artigo é descrita ocorrência e o dano causado pelo ácaro vermelho europeu Panonychus ulmi (Koch associado à cultura da videira. As coletas foram realizadas na safra 2005-2006 em Vitis vinifera L. da cultivar Merlot, nos municípios de Bento Gonçalves e Candiota, no Estado do Rio Grande do Sul, Brasil. As folhas infestadas apresentaram bronzeamento, com manchas avermelhadas na face adaxial, resultando na queda prematura das mesmas. Esse é o primeiro registro do ácaro vermelho europeu danificando a cultura da videira no Rio Grande do Sul.The occurrence and the damage caused for the European red spider mite Panonychus ulmi (Koch associated to the culture of the grapevine are described. The collections had been carried through in 2005-2006 seasons in Vitis vinifera L. of cultivating Merlot in Bento Gonçalves and Candiota counties, in the state of Rio Grande do Sul, Brazil. The infested leaves had presented bronzing, with spots redly in the adaxial face resulting in the premature fall. This is the first register of the European red mite damaging the culture of the grapevine in Rio Grande do Sul.

Ester Tuiksoo: Tuvi tänava korter võlus oma hea asukohaga / Ester Tuiksoo ; interv. Tuuli Koch

Index Scriptorium Estoniae

Tuiksoo, Ester, 1965-

2007-01-01

Ilmunud ka: Postimees : na russkom jazõke, 11. okt. 2007, lk. 3. Parlamendiliige vastab küsimustele Tullio Liblikult üüritava korteri kohta. Vt. samas: Risto Berendson, Tuuli Koch. Maadevahetuses kahtlustatav üürib Tuiksoole odavalt korterit; Risto Berendsoni intervjuu Tullio Liblikuga: Tullio Liblik: eelistasin Estrit üürnikuna vana tutvuse pärast. Lisa: Tullio Liblik; Rahvaliit kutsub Villu Reiljani kapo-komisjonist tagasi

Influence of yield on in vitro accumulation of aflatoxins in pecan (Carya illinoensis (Wang.) K. Koch) nutmeats.

Science.gov (United States)

McMeans, J L

1983-02-01

Pecans were harvested from trees (Carya illinoensis (Wang.) K. Koch) in November of 1977 through 1979. Kernel meals from high-, medium-, and low-yielding trees were inoculated with a spore suspension of Aspergillus parasiticus and incubated for 7 days at 25 degrees C. Significant differences in aflatoxin accumulation were found among the three substrates, with a direct correlation between high aflatoxin concentration and tree yield.

Influence of yield on in vitro accumulation of aflatoxins in pecan (Carya illinoensis (Wang.) K. Koch) nutmeats.

OpenAIRE

McMeans, J L

1983-01-01

Pecans were harvested from trees (Carya illinoensis (Wang.) K. Koch) in November of 1977 through 1979. Kernel meals from high-, medium-, and low-yielding trees were inoculated with a spore suspension of Aspergillus parasiticus and incubated for 7 days at 25 degrees C. Significant differences in aflatoxin accumulation were found among the three substrates, with a direct correlation between high aflatoxin concentration and tree yield.

Consecuencias en España del aislamiento del bacilo de Koch en la tuberculosis bovina (1882-1901)

OpenAIRE

Gutiérrez García, José Manuel

2001-01-01

El año más importante para la investigación de la tuberculosis fue 1882 en que Robert Koch descubrió el bacilo causante de tan desastrosa dolencia, identificado en material tuberculoso tanto humano como animal, y que confirmaba la unidad de la tisis en el hombre y en los animales y el hecho del contagio ante el mundo científico.

Urtica Dioica Distillate Regenerates Pancreatic Beta Cells in Streptozotocin-Induced Diabetic Rats

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Gohari, Ali; Noorafshan, Ali; Akmali, Masoumeh; Zamani-Garmsiri, Fahimeh; Seghatoleslam, Atefeh

2018-01-01

Background Urtica dioica is known as an anti-hyperglycemic plant. Urtica dioica distillate (UD) is a traditional Iranian drink, locally known as “aragh gazaneh”. In spite of its widespread consumption in Iran, according to traditional Iranian medicine, there is no scientific report on the usefulness of UD for diabetic patients. This survey was designed to evaluate its protective effects for the recovery from diabetes by determining the serum insulin, blood glucose, volume of pancreatic islets, and the number and volume of β-cells in diabetic rats. Methods A total of 48 Sprague-Dawley male rats (200-250 g) were randomly distributed into 6 groups (n=8), including non-diabetic plus distilled water (DW), non-diabetic plus UD, diabetic plus DW, diabetic plus UD, diabetic plus insulin, and diabetic plus glibenclamide. DW, UD, and glibenclamide were administered via intragastric gavage and insulin was injected subcutaneously. After four weeks of experiments, blood samples were collected for serum insulin and blood glucose assay. Pancreas was also evaluated using stereological method. The SPSS software was used for statistical analysis. Kruskal-Wallis, repeated measurements, and Mann-Whitney U test were applied for comparisons between the groups. Results The treatment of diabetic rats with UD reduced the blood glucose dramatically (P<0.001) and increased serum insulin levels significantly (P=0.03) in comparison to the diabetic plus DW rats. Treatment with UD did not affect the mean β-cell volumes in the diabetic rats when compared to the diabetic plus DW rats, but the islet volumes and β-cell numbers were significantly recovered. Conclusion UD treatment in diabetic rats improves hyperglycemia by partially restoring plasma insulin levels. The data suggest that UD prevents islet atrophy and/or regenerate pancreatic β-cells. PMID:29749986

THE INFLUENCE OF VARIABLE TEMPERATURE AND HUMIDITY ON THE PREDATION EFFICIENCY OF P. PERSIMILIS, N. CALIFORNICUS AND N. FALLACIS.

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Audenaert, J; Vangansbeke, D; Verhoeven, R; De Clercq, P; Tirry, L; Gobin, B

2014-01-01

Predatory mites like Phytoseiulus persimilis Athias-Henriot, Neoseiulus californicus McGregor and N. fallacis (Garman) (Acari: Phytoseiidae) are essential in sustainable control strategies of the two-spotted spider mite Tetranychus urticae Koch (Acari: Tetranychidae) in warm greenhouse cultures to complement imited available pesticides and to tackle emerging resistance. However, in response to high energy prices, greenhouse plant breeders have recently changed their greenhouse steering strategies, allowing more variation in temperature and humidity. The impact of these variations on biological control agents is poorly understood. Therefore, we constructed functional response models to demonstrate the impact of realistic climate variations on predation efficiency. First, two temperature regimes were compared at constant humidity (70%) and photoperiod (16L:8D): DIF0 (constant temperature) and DIF15 (variable temperature with day-night difference of 15°C). At mean temperatures of 25°C, DIF15 had a negative influence on the predation efficiency of P. persimilis and N. californicus, as compared to DIF0. At low mean temperatures of 15°C, however, DIF15 showed a higher predation efficiency for P. persimilis and N. californicus. For N. fallacis no difference was observed at both 15°C and 25°C. Secondly, two humidity regimes were compared, at a mean temperature of 25°C (DIFO) and constant photoperiod (16L:8D): RHCTE (constant 70% humidity) and RHALT (alternating 40% L:70%D humidity). For P. persimilis and N. fallacis RHCTE resulted in a higher predation efficiency than RHALT, for N. californicus this effect was opposite. This shows that N. californicus is more adapted to dry climates as compared to the other predatory mites. We conclude that variable greenhouse climates clearly affect predation efficiency of P. persimilis, N. californicus and N. fallacis. To obtain optimal control efficiency, the choice of predatory mites (including dose and application frequency

Growth analysis of cotton crops infested with spider mites. I. Light interception and radiation-use efficiency

International Nuclear Information System (INIS)

Sadras, V.O.; Wilson, L.J.

1997-01-01

Two-spotted spider mites (Tetranychus urticae Koch) are important pests of cotton (Gossypium hirsutum L.). The effects of mites on cotton photosynthesis have been investigated at the leaf and cytological level but not at the canopy level. Our objective was to quantify the effects of timing and intensity of infestation by mites on cotton radiation-use efficiency (RUE). Leaf area, light interception, RUE, canopy temperature, and leaf nitrogen concentration (LNC) were assessed during two growing seasons in crops artificially infested with mites between 59 and 127 d after sowing. Normal and okra-leaf cultivars were compared. A mite index (MI = natural log of the area under the curve of mite number vs thermal time) was used to quantify the cumulative effects of mites on RUE, LNC, and canopy temperature. Crop growth reduction due to mites was greater in early- than in late-infested crops Growth reduction was primarily due to reductions in RUE, but in the more severe treatments accelerated leaf senescence and, hence. reduced light interception also contributed to reductions in crop growth. At a given date, infested okra-leaf crops usually had greater RUE than their normal-leaf counterparts. Both plant types, however. responded similarly to a given level of mite infestation. The ability of the okra-leaf cultivar to maintain greater RUE levels can be attributed. therefore, to its relative inhospitality for the development of mite colonies rather than to an intrinsically greater capacity to maintain photosynthesis under mite damage. Canopy temperature, LNC, and RUE showed a similar, biphasic pattern of response to Ml. In the first phase, response variables were almost unaffected by mites. In the second phase, there was a marked decline in RUE and LNC and a marked increase in canopy temperature with increasing MI. These results suggest (i) some degree of compensatory photosynthesis at low to moderate levels of mite infestation, and (ii) reductions in RUE of mite

Comparison of nutritional properties of Stinging nettle (Urtica dioica) flour with wheat and barley flours

OpenAIRE

Adhikari, Bhaskar Mani; Bajracharya, Alina; Shrestha, Ashok K.

2015-01-01

Abstract Stinging nettle?(Urtica dioica. L) is a wild, unique herbaceous perennial flowering plant with Stinging hairs. It has a long history of use as a food sources as a soup or curries, and also used as a fiber as well as a medicinal herb. The current aim was to analyze the composition and bioactive compounds in Nepalese Stinging nettle. Chemical analysis showed the relatively higher level of crude protein (33.8%), crude fiber (9.1%), crude fat (3.6%), total ash (16.2%), carbohydrate (37.4...

High-antibacterial activity of Urtica spp. seed extracts on food and plant pathogenic bacteria.

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Körpe, Didem Aksoy; İşerı, Özlem Darcansoy; Sahin, Feride Iffet; Cabi, Evren; Haberal, Mehmet

2013-05-01

The aim of this study was to comparatively evaluate antibacterial activities of methanol (MetOH) and aqueous (dw) leaf (L), root (R) and seed (S) extracts of Urtica dioica L. (Ud; stinging nettle) and Urtica pilulifera L. (Up; Roman nettle) on both food- and plant-borne pathogens, with total phenolic contents and DPPH radical scavenging activities (DRSA). MetOH extracts of leaves and roots of U. dioica had the highest DRSA. Extracts with high antibacterial activity were in the order Up-LMetOH (13/16) > Ud-SMetOH (11/16) > Up-SMetOH (9/16). Results obtained with Up-SMetOH against food spoiling Bacillus pumilus, Shigella spp. and Enterococcus gallinarum with minimum inhibitory concentrations (MICs) in 128-1024 μg/ml range seem to be promising. Up-SMetOH also exerted strong inhibition against Clavibacter michiganensis with a considerably low MIC (32 μg/ml). Ud-SMetOH and Up-LMetOH were also effective against C. michiganensis (MIC = 256 and 1024 μg/ml, respectively). Ud-SMetOH and Ud-RMetOH had also antimicrobial activity against Xanthomonas vesicatoria (MIC = 512 and 1024 μg/ml, respectively). Results presented here demonstrate high-antibacterial activity of U. pilulifera extracts and U. dioica seed extract against phytopathogens for the first time, and provide the most comprehensive data on the antibacterial activity screening of U. pilulifera against food-borne pathogens. Considering limitations in plant disease control, antibacterial activities of these extracts would be of agricultural importance.

The landsnail Cepaea nemoralis regulates internal Cd levels when fed on Cd-enriched stinging nettle (Urtica dioica) leaves at low, field-relevant concentrations.

NARCIS (Netherlands)

Notten, M.J.M.; Oosthoek, A.; Rozema, J.; Aerts, R.

2006-01-01

We studied Cd accumulation in Cepaea nemoralis snails at low, but field-relevant Cd concentrations in the diet (Urtica dioica leaves). Six treatments of U. dioica plants were grown, resulting in leaf Cd concentrations between 0 and 2.6 μg g

In vitro bioaccessibility, transepithelial transport and antioxidant activity of Urtica dioica L. phenolic compounds in nettle based food products.

Science.gov (United States)

Bonetti, Gianpiero; Tedeschi, Paola; Meca, Giuseppe; Bertelli, Davide; Mañes, Jordi; Brandolini, Vincenzo; Maietti, Annalisa

2016-10-12

Nettle (Urtica dioica L.) is a well-known plant with a wide historical background use of stems, roots and leaves. Nettle leaves are an excellent source of phenolic compounds, principally 3-caffeoylquinic acid (3-CQA), caffeoylmalic acid (CMA) and rutin. The aim of this work was to evaluate the bioaccessibility (BAC), the bioavailability (BAV) and the antioxidant activity of nettle phenolic compounds present in foods and supplements. The BAC of nettle phenolics was evaluated with an in vitro dynamic digestion of real food matrices: the type of food matrix and chemical characteristic affected the kinetics of release and solubilization, with the highest BAC after duodenal digestion. A study of duodenal trans epithelial transport evidenced low bioavailability of native forms of 3-CQA, CMA and rutin. Simulation of colonic metabolism confirmed that phenolic compounds are fermented by gut microflora, confirming the need for further investigations on the impact of phenolic compounds at the large intestine level. Photochemiluminescence assay of the simulated digestion fluids demonstrated that ingestion of Urtica based foods contributes to create an antioxidant environment against superoxide anion radicals in the entire gastrointestinal tract (GIT).

The role of methyl salicylate in prey searching behavior of the predatory mite phytoseiulus persimilis.

Science.gov (United States)

De Boer, Jetske G; Dicke, Marcel

2004-02-01

Many carnivorous arthropods use herbivore-induced plant volatiles to locate their prey. These plant volatiles are blends of up to hundreds of compounds. It is often unknown which compounds in such a complex volatile blend represent the signal to the foraging carnivore. We studied the role of methyl salicylate (MeSA) as part of the volatile blend in the foraging behavior of the predatory mite Phytoseiulus persimilis by using a Y-tube olfactometer. MeSA is one of the compounds released by lima bean, infested with Tetranychus urticae--a prey species of the predatory mite. MeSA attracted satiated predatory mites in a dose-dependent way with optimum attraction at a dose of 0.2 microg. Predatory mites did not discriminate between a prey-induced lima bean volatile blend (that contains MeSA) and a prey-induced volatile blend to which an extra amount of synthetic MeSA had been added. However, they preferred a MeSA-containing volatile blend (induced by T. urticae) to an otherwise similar but MeSA-free blend (induced by jasmonic acid). Adding synthetic MeSA to the MeSA-free blend significantly increased the mites' choice for this odor, suggesting an important role for MeSA. This study is a new step toward unraveling the role of herbivore-induced plant volatiles in the foraging behavior of predatory arthropods.

Urtica dioica inhibits cell growth and induces apoptosis by targeting Ornithine decarboxylase and Adenosine deaminase as key regulatory enzymes in adenosine and polyamines homeostasis in human breast cancer cell lines.

Science.gov (United States)

Fattahi, Sadegh; Ghadami, Elham; Asouri, Mohsen; Motevalizadeh Ardekanid, Ali; Akhavan-Niaki, Haleh

2018-02-28

Breast cancer is a heterogeneous and multifactorial disease with variable disease progression risk, and treatment response. Urtica dioica is a traditional herb used as an adjuvant therapeutic agent in cancer. In the present study, we have evaluated the effects of the aqueous extract of Urtica dioica on Adenosine deaminase (ADA) and Ornithine decarboxylase (ODC1) gene expression in MCF-7, MDA-MB-231, two breast cancer cell lines being estrogen receptor positive and estrogen receptor negative, respectively.  Cell lines were cultured in suitable media. After 24 h, different concentrations of the extract were added and after 72 h, ADA and ODC1 gene expression as well as BCL2 and BAX apoptotic genes were assessed by Taqman real time PCR assay. Cells viability was assessed by MTT assay, and apoptosis was also evaluated at cellular level. The intra and extracellular levels of ODC1 and ADA enzymes were evaluated by ELISA. Results showed differential expression of ADA and ODC1 genes in cancer cell lines. In MCF-7 cell line, the expression level of ADA was upregulated in a dose-dependent manner but its expression did not change in MDA-MB cell line. ODC1 expression was increased in both examined cell lines. Also, increased level of the apoptotic BAX/BCL-2 ratio was detected in MCF-7 cells. These results demonstrated that Urtica dioica induces apoptosis in breast cancer cells by influencing ODC1 and ADA genes expression, and estrogen receptors. The different responses observed with these cell lines could be due to the interaction of Urtica dioica as a phytoestrogen with the estrogen receptor.

Infestação de Amblyomma rotundatum (Koch (Acari, Ixodidae em sapos Bufo ictericus (Spix (Amphibia, Bufonidae: novo registro de hospedeiro Infestation of Amblyomma rotundatum (Koch (Acari, Ixodidae ticks on Bufo ictericus (Spix (Amphibia, Bufonidae: new host record

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Germano Woehl Jr.

2002-06-01

Full Text Available Bufo ictericus Spix, 1824 toad population (N = 125 foraging in lighted areas in the Corupá Municipality, Santa Catarina State, was surveyed to evaluate the prevalence (percentage of infestation and the mean infestation intensity of Amblyomma rotundatum Koch, 1844 (Acari, Ixodidae ticks. The prevalence was of 19.2% and the mean infestation intensity was 7.4 ticks per infested toad. For the first time B. ictericus as host of A. rotundatum is reported.

Food-chain transfer of cadmium and zinc from contaminated Urtica dioica to Helix aspersa and Lumbricus terrestris.

Science.gov (United States)

Sinnett, Danielle E; Hodson, Mark E; Hutchings, Tony R

2009-08-01

The present study examines the potential of Urtica dioica as an ecologically relevant species for use in ecotoxicological testing. It is prevalent in degraded ecosystems and is a food source for invertebrates. Urtica dioica grown in hydroponic solutions containing from less than 0.003 to 5.7 mg Cd/L or from 0.02 to 41.9 mg Zn/L accumulated metals resulting in leaf tissue concentrations in the range of 0.10 to 24.9 mg Cd/kg or 22.5 to 2,772.0 mg Zn/kg. No toxicological effects were apparent except at the highest concentrations tested, suggesting that this species may be an important pathway for transfer of metals to primary plant consumers. Helix aspersa and Lumbricus terrestris were fed the Cd- and Zn-rich leaves of U. dioica for six and four weeks, respectively. Cadmium and Zn body load increased with increasing metal concentration in the leaves (p nettle leaves with concentrations of approximately 23 mg Cd/kg and 3,400 mg Zn/kg. Models demonstrate that L. terrestris Cd tissue concentrations (r2 = 0.74, p < 0.001) and H. aspersa Zn tissue concentrations (r(2) = 0.69, p < 0.001) can be estimated from concentrations of Cd and Zn within the leaves of U. dioica and suggest that reasonably reproducible results can be obtained using these species for ecotoxicological testing.

Inter- and intra-guild interactions related to aphids in nettle (Urtica dioica L.) strips closed to field crops.

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Alhmedi, A.; Haubruge, Eric; Bodson, Bernard; Francis, Frédéric

2006-01-01

A field experiment designed to assess the biodiversity related to nettle strips closed to crops, and more particularly the aphid and related beneficial populations, was established in experimental farm located in Gembloux (Belgium). Margin strips of nettle (Urtica dioica) closed to wheat (Triticum aestivum), green pea (Pisum sativum) and rape (Brassicae napus) fields were investigated. The diversity, abundance of aphids and related predators were analysed according to the plant crop species a...

Antioxidant and wound healing potential of saponins extracted from the leaves of Algerian Urtica dioica L.

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Razika, Laoufi; Thanina, Affif Chaouche; Nadjiba, Chebouti-Meziou; Narimen, Benhabyles; Mahdi, Dahmani Mohamed; Karim, Arab

2017-05-01

The Nettle is a herbaceous and vivace plant of Asian origin. It is integrated in several areas especially alimentary, agricultural, industrial and medicinal. The aim of this work is to demonstrate through pharmacological tests a possible antioxidant and wound healing effect of crude saponins of the leaves of Urtica dioica L. The extraction method is based on the degree of solubility of saponins in organic solvents. The antioxidant activity of the leaves extracts was evaluated by the diphenyl-picryl-hydrazyl test (DPPH). The wound healing effect is interpreted on the basis of the healing time and the evaluation of the surface of wounds. It appears from this study that the Nettle is rich in saponins, either 4.08% to 30 g of plant powder. The results also showed significant antioxidant effect similar to that of ascorbic acid (p> 0.05) with an IC 50 of 0.159mg/ml. As regards the healing power, treatment of rats with the product based on crude saponins is achieved after 15 days, either 100% of wound reduction. This value is much higher than that obtained by the reference product (Madécassol®) on the same duration of treatment with 93.73% of wound reduction. The achievement of pharmacological tests has thus shown that crude saponins extracted from the leaves of Urtica dioica L. can be integrated into the pharmaceutical field or even in cosmetic.

Biologia e tabela de vida de Tetranychus desertorum (Acari: Tetranychidae sobre folhas de feijão (Phaseolus vulgaris Biology and life table of Tetranychus desertorum (Acari: Tetranychidae on leaves of kidney bean (Phaseolus vulgaris

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Edgar Rivero

2009-03-01

Full Text Available Biological aspects and life table of the red spider mite, Tetranychus desertorum Banks, 1900, were studied on leaf discs of kidney bean (Phaseolus vulgaris Linnaeus cultivar "Tacarigua" under laboratory conditions (28 ± 2ºC, 70 ± 10% R.H. and 12:12h. Our results showed that total developmental time was 6.8 days for females, with partial duration of immature stages corresponding to 3.8, 1.4, 1.0 and 0.7 for egg, larva, protonymph and deutonymph, respectively. Preoviposition, oviposition and postoviposition periods were 1.1, 8.4 and 1.3 days, respectively; and the higher mean fecundity (6.93 eggs/female/day was observed on day 4. Female mean longevity was 10 days. The life table parameters recorded were: net reproduction rate (Ro = 41.10 individuals; generation time (T = 11.15 days; intrinsic natural growth (r m = 0.144 individuals/female/day, and finite natural increase rate (λ = 1.155 individuals/female. Our findings could be a basis for further studies devoted to determine damage and control strategies for T. desertorum on kidney bean crops.

Interactions in a tritrophic acarine predator-prey metapopulation system III

DEFF Research Database (Denmark)

Nachman, Gösta; Zemek, R.

2002-01-01

Spider mites are serious pests on many economically important plant species, because they may reduce plant productivity and, at high mite densities, overexploit and even kill the host plants. We have conducted a series of greenhouse experiments to quantify the effects of two-spotted spider mites...... (Tetranychus urticae) on host plants (Phaseolusvulgaris). The average amount of chlorophyll per cm2 leaf area was used as a measure of plant condition. It was shown that chlorophyll concentration decreases with plant age and intensity of spider mite feeding. Damage caused by spider mites was assessed visually...... caused by spider mites (D). D takes values between 0 (no injury) and 1 (all leaves dead). A highly significant positive relationship between the instantaneous spider mite density and D was found, even though D is expected to reflect the cumulated density of mites (mite-days). A model of plant growth...

Antimutagenic and antioxidant activity of a protein fraction from aerial parts of Urtica dioica.

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Di Sotto, Antonella; Mazzanti, Gabriela; Savickiene, Nijole; Staršelskytė, Rasa; Baksenskaite, Vaida; Di Giacomo, Silvia; Vitalone, Annabella

2015-06-01

Urtica dioica L. (Urticaceae), stinging nettle, has been employed as a folklore remedy for a wide spectrum of ailments, including urinary disorders, prostatic hyperplasia, and liver diseases. It has been also used traditionally for cancer treatment. To evaluate the potential chemopreventive properties of a protein fraction from the aerial part of Urtica dioica (namely UDHL30). UDHL30 has been tested for the antimutagenic activity in bacteria (50-800 μg/plate; Ames test by the preincubation method) and for the cytotoxicity on human hepatoma HepG2 cells (0.06-2 mg/mL; 24 and 48 h incubation). Moreover, the antioxidant activity of UDHL30 (0.1-1200 μg/mL; ABTS and superoxide-radical scavenger assays) was evaluated as potential protective mechanisms. UDHL30 was not cytotoxic on HepG2 cells up to 2 mg/mL; conversely, it exhibited a strong antimutagenic activity against the mutagen 2-aminoanthracene (2AA) in all strains tested (maximum inhibition of 56, 78, and 61% in TA98, TA100, and WP2uvrA strains, respectively, at 800 μg/plate). In addition, a remarkable scavenging activity against ABTS radical and superoxide anion (IC50 values of 19.9 ± 1.0 μg/mL and 75.3 ± 0.9 μg/mL, respectively) was produced. UDHL30 possesses antimutagenic and radical scavenging properties. Being 2AA a pro-carcinogenic agent, we hypothesize that the antimutagenicity of UDHL30 can be due to the inhibition of CYP450-isoenzymes, involved in the mutagen bioactivation. The radical scavenger ability could contribute to 2AA-antimutagenicity. These data encourage further studies in order to better define the potential usefulness of UDHL30 in chemoprevention.

Optimization of spray deposition and Tetranychus urticae control with air assisted and electrostatic sprayer

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Denise Tourino Rezende de Cerqueira

Full Text Available ABSTRACT: Improved spray deposition can be attained by electrostatically charging spray droplets, which increases the attraction of droplets to plants and decreases operator exposure to pesticide and losses to the environment. However, this technique alone is not sufficient to achieve desirable penetration of the spray solution into the crop canopy; thus, air assistance can be added to the electrostatic spraying to further improve spray deposition. This study was conducted to compare different spraying technologies on spray deposition and two-spotted spider mite control in cut chrysanthemum. Treatments included in the study were: conventional TJ 8003 double flat fan nozzles, conventional TXVK-3 hollow cone nozzles, semi-stationary motorized jet launched spray with electrostatic spray system (ESS and air assistance (AA, and semi-stationary motorized jet launched spray with AA only (no ESS. To evaluate the effect of these spraying technologies on the control of two-spotted spider mite, a control treatment was included that did not receive an acaricide application. The AA spraying technology, with or without ESS, optimized spray deposition and provided satisfactory two-spotted spider mite control up to 4 days after application.

Urtica dioica Effect on Malonyl-CoA Decarboxylase

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Qujeq

2014-09-01

Full Text Available Background The malonyl-CoA decarboxylase (MCD, EC.4.1.1.9 enzyme regulates malonyl-CoA levels. The effect of aerial parts extracts of Urtica dioica (UD on MCD is poorly understood. Objectives The present experiment was undertaken to evaluate the effect of UD aerial parts extracts on MCD level. Materials and Methods In this experimental study, two groups of rats were used: normal and hyperglycemic group. Then UD aerial parts extracts (5 mg /500 µL administrated to the hyperglycemic group of rats and finally, the MCD and insulin levels were measured in both groups. Results Interestingly, we observed that the UD aerial parts extracts powder caused a significant (P < 0.05 increase in insulin level during the experiment, from the base level of 0.36 ± 0.07 μg/L to the peak value of 0.52 ± 0.15 μg/L. Also, it caused a significant (P < 0.05 decrease in MCD level, from the base level of 29.68 ±1.29 pg/mL to the bottom value of 22.12 ± 2.41 pg/mL. Conclusions The results of the present study indicate that UD aerial part extracts would decrease MCD level in hyperglycemic rats.

Antioxidant-Rich Fraction of Urtica dioica Mediated Rescue of Striatal Mito-Oxidative Damage in MPTP-Induced Behavioral, Cellular, and Neurochemical Alterations in Rats.

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Bisht, Rohit; Joshi, Bhuwan Chandra; Kalia, Ajudhiya Nath; Prakash, Atish

2017-09-01

Parkinson's disease (PD) having a complex and multi-factorial neuropathology includes mainly the degeneration of the dopaminergic nigrostriatal pathway, which is a cumulative effect of depleted endogenous antioxidant enzymes, increased oxidative DNA damage, mitochondrial dysfunction, excitotoxicity, and neuroinflammation. The present study was designed to investigate the neuroprotective effect of a potent antioxidant from Urtica dioica in a 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine (MPTP) model of parkinsonism. MPTP was administered intranigrally for the induction of PD in male Wistar rats. Behavioral alterations were assessed in between the study period. Animals were sacrificed immediately after behavioral session, and different biochemical, cellular, and neurochemical parameters were measured. Intranigrally repeated administration of MPTP showed significant impairment of motor co-ordination and marked increase of mito-oxidative damage and neuroinflammation in rats. Intranigral MPTP significantly decreases the dopamine and its metabolites with impairment of dopaminergic cell density in rat brain. However, post-treatment with the potent antioxidant fraction of Urtica dioica Linn. (UD) (20, 40, 80 mg/kg) improved the motor function, mito-oxidative defense alteration significantly and dose dependently in MPTP-treated rats. In addition, the potent antioxidant fraction of UD attenuated the pro-inflammatory cytokines (TNF-α and IL-β) and restored the level of dopamine and its metabolites in MPTP-induced PD in rats. Moreover, minocycline (30 mg/kg) with lower dose of UD (20 mg/kg) had significantly potentiated the protective effect of minocycline as compared to its effect with other individual drug-treated groups. In conclusion, Urtica dioica protected the dopaminergic neurons probably by reducing mito-oxidative damage, neuroinflammation, and cellular alteration along with enhanced neurotrophic potential. The above results revealed that the antioxidant rich

Effects of various doses of selenite on stinging nettle (Urtica dioica L.).

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Krystofova, Olga; Adam, Vojtech; Babula, Petr; Zehnalek, Josef; Beklova, Miroslava; Havel, Ladislav; Kizek, Rene

2010-10-01

The aim of this study was to investigate the effects of selenium (Se) on the growth, accumulation and possible mechanisms of Se transport in certain parts (roots, leaves, stamp and apex) of nettle (Urtica dioica L.) plants. Se was supplemented by one-shot and two repeated doses to the soil (2.0 and 4.0 mg Se per kg of substrate). Selenium content in roots increased linearly with dose and was significantly higher compared to other plant parts of interest. However, growth of the above-ground parts of plant as well as roots was slightly inhibited with increasing selenium concentration in comparison to the untreated plants. The content of phytochelatin2, a low molecular mass peptide containing a sulfhydryl group, correlated well with the Se content. This suggests a possible stimulation of synthesis of this plant peptide by Se.

Effects of Various Doses of Selenite on Stinging Nettle (Urtica dioica L.)

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Krystofova, Olga; Adam, Vojtech; Babula, Petr; Zehnalek, Josef; Beklova, Miroslava; Havel, Ladislav; Kizek, Rene

2010-01-01

The aim of this study was to investigate the effects of selenium (Se) on the growth, accumulation and possible mechanisms of Se transport in certain parts (roots, leaves, stamp and apex) of nettle (Urtica dioica L.) plants. Se was supplemented by one-shot and two repeated doses to the soil (2.0 and 4.0 mg Se per kg of substrate). Selenium content in roots increased linearly with dose and was significantly higher compared to other plant parts of interest. However, growth of the above-ground parts of plant as well as roots was slightly inhibited with increasing selenium concentration in comparison to the untreated plants. The content of phytochelatin2, a low molecular mass peptide containing a sulfhydryl group, correlated well with the Se content. This suggests a possible stimulation of synthesis of this plant peptide by Se. PMID:21139861

Effects of Various Doses of Selenite on Stinging Nettle (Urtica dioica L.

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Miroslava Beklova

2010-10-01

Full Text Available The aim of this study was to investigate the effects of selenium (Se on the growth, accumulation and possible mechanisms of Se transport in certain parts (roots, leaves, stamp and apex of nettle (Urtica dioica L. plants. Se was supplemented by one-shot and two repeated doses to the soil (2.0 and 4.0 mg Se per kg of substrate. Selenium content in roots increased linearly with dose and was significantly higher compared to other plant parts of interest. However, growth of the above-ground parts of plant as well as roots was slightly inhibited with increasing selenium concentration in comparison to the untreated plants. The content of phytochelatin2, a low molecular mass peptide containing a sulfhydryl group, correlated well with the Se content. This suggests a possible stimulation of synthesis of this plant peptide by Se.

تأثير الكثافة العددية المختلفة لأدوار الحلم ذي البقعتين (Tetranychus urticae (Koch في حياتية المفترس ((Mulsant gilvifrons Stethorus.

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يوسف دخيل راشد

2018-03-01

Full Text Available اجريت دراسة مختبرية لبيان تأثير الكثافة العددية المختلفة لأدوار الحلم ذي البقعتين Tetranychus urticae (Koch في حياتية المفترس  Stethorus gilvifrons عند درجة حرارة 30مْ ورطوبة نسبية 70±5%, وبيَنت الدراسة ﺃن لاختلاف الكثافات العددية 5, 10, 20, 40 و 80 حلمة/ورقه تأثيرﴽ كبيرﴽ على حياتية المفترس, وكانت الكثافة العددية  80حلمة ملائمة, ﺇذ وصلت عندها يرقات وبالغات المفترس ﺃعلى مستوى من التطور والاستهلاك والتكاثر, بينما وجدت الكثافة العددية 5 هي ﺃقل كثافة عددية تستطيع يرقة المفترس ﺃن تكمل تطورها بنجاح : ﺃظهرت الدراسة ﺃن زيادة الكثافة العددية للحلم ذي البقعتين تعني زيادة معدل الاستهلاك اليومي لكل عمر يرقي ﺇذ وجد عند الكثافة العددية 80 حلمة ﺃنَ ﺃعلى معدل استهلاك للاعمار اليرقية الاربعة بلغ 23.3 , 28.3 , 37 , 44.6 حلمة على التوالي, بينما وجد عند الكثافة العددية 5 حلمات بينما ﺃقل معدل للاستهلاك للأطوار اليرقية الاربعة  بلغ 4.0, 5, 5,5 حلمات  على التوالي, وكانت ﺃقصر مدة لتطور الاعمار اليرقية عند الكثافة العددية 80 حلمة اذ بلغت 1.6, 1, 1.3, 2.0 يوما بينما بلغت اطول مدة لتطور الاعمار اليرقية عند الكثافة العددية 5 حلمات ﺇذ بلغت 2, 3, 3.3 , 6.6 يوما على العائل. بيَنت النتائج ﺃن عدد البيض الذي تضعه انثى المفترس خلال حياتها تتأثر بالكثافة �

Cytotoxic Activity and Composition of Petroleum Ether Extract from Magydaris tomentosa (Desf. W. D. J. Koch (Apiaceae

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Giuseppina Autore

2015-01-01

Full Text Available The petroleum ether extract of Magydaris tomentosa flowers (Desf. W. D. J. Koch has been analyzed by GC-MS. It is mainly constituted by furanocoumarins such as xanthotoxin, xanthotoxol, isopimpinellin, and bergaptene. Other coumarins such as 7-methoxy-8-(2-formyl-2-methylpropyl coumarin and osthole also occurred. The antiproliferative activity of Magydaris tomentosa flower extract has been evaluated in vitro on murine monocye/macrophages (J774A.1, human melanoma (A375 and human breast cancer (MCF-7 tumor cell lines, showing a major activity against the latter.

Characterization of antioxidant and antimicrobial activities of nettle leaves (Urtica dioica L.

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Kukrić Zoran Z.

2012-01-01

Full Text Available Samples of stinging nettle or common nettle (Urtica dioica L. were collected from the area of Banja Luka. To measure and evaluate the content of chlorophyll (a and b, carotenoids, and soluble proteins, as well as peroxidase activity (POD, EC 1.11.1.7., fresh nettle leaves of different developmental stages were used. Dried nettle leaves were used to obtain ethanol extract. The dry residue of ethanol extract was dissolved in methanol and the obtained solution was used to determine the content of total phenols, flavonoids, flavonols, as well as non-enzymatic antioxidant activity and antimicrobial activity. The non-enzymatic antioxidant activity was determined by different methods: FRAP, DPPH, and ABTS. The results were compared to those of standard substances like vitamin C, BHT, and BHA. Antimicrobial activity was screened by using macrodilution method. The obtained results showed insignificantly higher content of chlorophyll, carotenoids, and proteins in young nettle leaves as well as an increase in the soluble peroxidase activities. Native electrophoresis of the soluble fraction showed the presence of two peroxidase isophorms in the soluble protein fraction of nettle leaves. The total phenolic content in nettle extracts amounted to 208.37 mg GAE/gdw, the content of total flavonoids was 20.29 mg QE/gdw, and the content of total flavonols was 22.83 mg QE/gdw. The antioxidant activity determined by FRAP method was 7.50 mM Fe(II/gdw, whereas the antioxidant activity measured by using DPPH and ABTS methods, with IC50 values, were 31.38 and 23.55 μg mL-1, respectively. These results showed the weak and moderate antioxidant capacity of stinging nettle. Extract of Urtica dioica L. was tested for antibacterial acivity against various Grampositive and Gram-negative bacteria: Bacillus subtilis IP 5832, Lactobacillus plantarum 299v (Lp299v, Pseudomonas aeruginosa, and Escherichia coli isolated from food and Escherichia coli isolated from urine samples

Antihypoxic activities of Eryngium caucasicum and Urtica dioica.

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Khalili, M; Dehdar, T; Hamedi, F; Ebrahimzadeh, M A; Karami, M

2015-09-01

Urtica dioica and Eryngium spp. have been used in traditional medicine for many years. In spite of many works, nothing is known about their protective effect against hypoxia-induced lethality. Protective effects of U. dioica (UD) aerial parts and E. caucasicum (EC) inflorescence against hypoxia-induced lethality in mice were evaluated by three experimental models of hypoxia, asphyctic, haemic and circulatory. Statistically significant protective activities were established in some doses of extracts in three models. Antihypoxic activity was especially pronounced in polyphenol fractions in asphyctic model. EC polyphenol fraction at 400 mg/kg prolonged survival time (48.80 ± 4.86, p 0.05). It was the most effective extract in circulatory model, too. It prolonged survival time significantly respect to control group (p < 0.001). UD extracts protected the mice but the response was not dose-dependent. In haemic model, extracts of EP significantly and dose dependently prolonged survival time as compared to control group (p < 0.001). At 600 mg/kg, EP was the most effective one, being capable of keeping the mice alive for 12.71 ± 0.75 min. Only the concentration of 300 mg/kg of UD was effective (p < 0.001). Extracts showed remarkable antihypoxic effects. Pharmacological effects may be attributed to the presence of polyphenols in the extracts.

Antioxidant Properties of Pecan Nut [Carya illinoinensis (Wangenh.) C. Koch] Shell Infusion

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Pinheiro do Prado, A. C.; Monalise Aragao, A.; Fett, R.; Block, J. M.

2009-07-01

The nutritional composition of Pecan nut [Ca rya illinoinensis (Wangenh.) C. Koch] shells and the total phenolic and condensed tannin contents of Pecan nut shell infusion were determined and the antioxidant activity of the infusion was evaluated through ABTS, DPPH and {beta}-carotene/linoleic acid systems. The shell presented high fiber content (48% {+-} 0.06), the total phenolic content ranged from 116 to 167 mg GAE/g and the condensed tannin content was between 35 and 48 mg CE/g. The antioxidant activity varied from 1112 and 1763 {mu}mol TEAC/g in the ABTS system. In the DPPH method, the antioxidant activity was from 305 to 488 mg TEAC/g (30 minutes reaction) and from 482 to 683 mg TEAC/g (24 h reaction). The oxidation inhibition percentage obtained in the {beta}-carotene/linoleic acid system varied from 70 to 96%. The results indicated the high phenolic content and antioxidant activity of Pecan nut shell infusion. (Author) 28 refs.

Evaluation of alpha- amylase inhibition by Urtica dioica and Juglans regia extracts.

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Rahimzadeh, Mahsa; Jahanshahi, Samaneh; Moein, Soheila; Moein, Mahmood Reza

2014-06-01

One strategy for the treatment of diabetes is inhibition of pancreatic α- amylase. Plants contains different chemical constituents with potential for inhibition of α-amylase and hence maybe used as therapeutic. Urtica dioica and Juglans regia Linn were tested for α-amylase inhibition. Different concentrations of leaf aqueous extracts were incubated with enzyme substrate solution and the activity of enzyme was measured. For determination of the type of inhibition, Dixon plot was depicted. Acarbose was used as the standard inhibitor. Both plant extracts showed time and concentration dependent inhibition of α-amylase. 60% inhibition was seen with 2 mg/ml of U. dioica and 0.4 mg/ml of J. regia aqueous extract. Dixon plots revealed the type of α-amylase inhibition by these two extracts as competitive inhibition. Determination of the type of α-amylase inhibition by these plant extracts could provide by successful use of plant chemicals as drug targets.

Evaluation of alpha- amylase inhibition by Urtica dioica and Juglans regia extracts

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Mahsa Rahimzadeh

2014-06-01

Full Text Available Objective(s:One strategy for the treatment of diabetes is inhibition of pancreatic α- amylase. Plants contains different chemical constituents with potential for inhibition of α-amylase and hence maybe used as therapeutic. Materials and Methods: Urtica dioica and Juglans regia Linn were tested for α-amylase inhibition. Different concentrations of leaf aqueous extracts were incubated with enzyme substrate solution and the activity of enzyme was measured. For determination of the type of inhibition, Dixon plot was depicted. Acarbose was used as the standard inhibitor. Results: Both plant extracts showed time and concentration dependent inhibition of α-amylase. 60% inhibition was seen with 2 mg/ml of U. dioica and0.4 mg/ml of J. regia aqueous extract. Dixon plots revealed the type of α-amylase inhibition by these two extracts as competitive inhibition. Conclusion: Determination of the type of α-amylase inhibition by these plant extracts could provide by successful use of plant chemicals as drug targets.

The effect of Urtica dioica extract on the number of astrocytes in the dentate gyrus of diabetic rats.

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Jahanshahi, M; Golalipour, M J; Afshar, M

2009-05-01

Diabetes mellitus is associated with cerebral alterations in both human and animal models of the disease. These alterations include abnormal expression of hypothalamic neuropeptides and hippocampal astrogliosis. Urtica dioica (Nettle) is among several species listed for their use against diabetes in folk medicine. The aim of this study was the evaluation of the astrocyte number in the dentate gyrus of diabetic rats after treatment with nettle. A total of 21 male albino Wistar rats were used in the present study. The animals were divided into three groups: control, nettle-untreated diabetic, and nettle treated diabetic. Hyperglycaemia was induced by streptozotocin (80 mg/kg) in the animals of the diabetic and treatment groups. One week after injection of the streptozotocin, the animals in the treatment group received a hydroalcoholic extract of Urtica dioica (100 mg/kg/day) for 4 weeks intraperitoneally. After a 5-week survival period, all the rats were sacrificed and coronal sections were taken from the dorsal hippocampal formation of the right cerebral hemispheres. The area densities of the astrocytes were measured and compared between the three groups (p < 0.05). The number of astrocytes increased in the diabetic rats (24.06 +/- 9.57) compared with the controls (17.52 +/- 6.66). The densities in the treated rats (19.50 +/- 6.16) were lower than in the diabetic rats. Furthermore, the control and treated rats showed similar densities. We concluded that U. dioica extract helped compensate for astrocytes in the treatment rats dentate gyrus in comparison with diabetic rats.

Effect of ecological surface treatment method on friction strength properties of nettle (urtica dioica) fibre yarns

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Şansal, S.; Mıstık, S. I.; Fettahov, R.; Ovalı, S.; Duman, M.

2017-10-01

Over the last few decades, more attention is given to lignocellulose based fibres as reinforcement material in the polymer composites owing to the environmental pollution caused by the extensive usage of synthetic and inorganic fibres. Developing new natural fibre reinforced composites is the focus of many researches nowadays. They are made from renewable resources and they have less environmental effect in comparison to inorganic fibre reinforced composites. The interest of consumers in eco-friendly natural fibres and textiles has increased in recent years. Unlike inorganic fibres, natural fibres present light weight, high strength/density ratio and are readily available, environmentally friendly and biodegradable. Many different types of natural fibres are exploited for the production of biodegradable polymer composites. The nettle (Urtica dioica L.) is a well-known plant growing on rural sites of Europe, Asia, and North America. Nettle plant contains fibre similar to hemp and flax. However, similar to other natural fibres, nettle fibres are poorly compatible with the thermoplastic matrix of composites, due to their hydrophilic character which reduces mechanical properties of nettle fibre reinforced thermoplastics. In order to improve the fibrematrix adhesion of the natural fibre reinforced composites, surface treatment processes are applied to the lignocellulose fibres. In this study nettle (urtica dioica) fibre yarns were treated with NaOH by using conventional, ultrasonic and microwave energy methods. After treatment processes tensile strength, elongation, friction strength and SEM observations of the nettle fibre yarns were investigated. All treatment processes were improved the tensile strength, elongation and friction strength properties of the nettle fibre yarns. Also higher tensile strength, elongation and friction strength properties were obtained from treated nettle fibre yarns which treated by using microwave energy method.

Antioxidant Properties of Pecan Nut [Carya illinoinensis (Wangenh. C. Koch] Shell Infusion

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Fett, Roseane

2009-09-01

Full Text Available The nutritional composition of Pecan nut [Carya illinoinensis (Wangenh. C. Koch] shells and the total phenolic and condensed tannin contents of Pecan nut shell infusion were determined and the antioxidant activity of the infusion was evaluated through ABTS, DPPH and β-carotene/linoleic acid systems. The shell presented high fiber content (48% ± 0.06, the total phenolic content ranged from 116 to 167 mg GAE/g and the condensed tannin content was between 35 and 48 mg CE/g. The antioxidant activity varied from 1112 and 1763 μmol TEAC/g in the ABTS system. In the DPPH method, the antioxidant activity was from 305 to 488 mg TEAC/g (30 minutes reaction and from 482 to 683 mg TEAC/g (24 h reaction. The oxidation inhibition percentage obtained in the β-carotene/linoleic acid system varied from 70 to 96%. The results indicated the high phenolic content and antioxidant activity of Pecan nut shell infusion.La composición nutricional de la cáscara de nuez Pecana [Carya illinoinensis (Wangenh. C. Koch] y los contenidos de fenoles totales y de taninos condensados de la infusión de la cáscara de nuez Pecana se determinaron en este trabajo. La actividad antioxidante de la infusión se evaluó a través de los sistemas ABTS, DPPH y β-caroteno/ácido linoleico. La cáscara presentó un contenido elevado de fibras (48% ± 0,06, el contenido de fenoles totales varió de 116 a 167 mg GAE/g y el de taninos condensados se encontró entre 35 y 48 mg CE/g. La actividad antioxidante varió entre 1112 y 1763 μmol TEAC/g en el sistema ABTS. Por el método DPPH, la actividad antioxidante fue de 305 a 488 mg TEAC/g (30 minutos de reacción y de 482 a 683 mg TEAC/g (24 h de reacción. El porcentaje de inhibición de la oxidación que se obtuvo en el sistema β -caroteno/ácido linoleico varió de 70 a 96%. Los resultados indicaron un elevado contenido de fenoles y una elevada actividad antioxidante para la infusión de la cáscara de nuez Pecana.

New records of water mites of the genus Atractides Koch, 1837 (Acari: Hydrachnidia, Hygrobatidae) from Thailand, Malaysia and Sulawesi (Indonesia), with the description of four new species

NARCIS (Netherlands)

Pesic, V.; Smit, H.

2009-01-01

New records of water mites of the genus Atractides Koch, 1837 (Acari: Hydrachnidia, Hygrobatidae) from Thailand, Malaysia and Sulawesi are presented. Four species new to science, Atractides siamis, A. malayensis, A. tahanensis and A. sulawesiensis, are described; a first description of the male is

Bacterial origin of a diverse family of UDP-glycosyltransferase genes in the Tetranychus urticae genome

NARCIS (Netherlands)

Ahn, S.J.; Dermauw, W.; Wybouw, N.; Heckel, D.G.; Van Leeuwen, T.

2014-01-01

UDP-glycosyltransferases (UGTs) catalyze the conjugation of a variety of small lipophilic molecules with uridine diphosphate (UDP) sugars, altering them into more water-soluble metabolites. Thereby, UGTs play an important role in the detoxification of xenobiotics and in the regulation of

A burst of ABC genes in the genome of the polyphagous spider mite Tetranychus urticae

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Dermauw, W.; Osborne, E.J.; Clark, R.M.; Grbić, M.; Tirry, L.; Van Leeuwen, T.

2013-01-01

Background: The ABC (ATP-binding cassette) gene superfamily is widespread across all living species. The majority of ABC genes encode ABC transporters, which are membrane-spanning proteins capable of transferring substrates across biological membranes by hydrolyzing ATP. Although ABC transporters

The interaction of two-spotted spider mites, Tetranychus urticae Koch, with Cry protein production and predation by Amblyseius andersoni (Chant) in Cry1Ac/Cry2Ab cotton and Cry1F maize.

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Crops producing insecticidal crystal (Cry) proteins from the bacterium, Bacillus thuringiensis (Bt), are an important tool for managing lepidopteran pests on cotton and maize. However, the effects of these Bt crops on non-target organisms, especially natural enemies that provide biological control s...

[Systematically induced effects of Tetranychus cinnabarinus infestation on chemical defense in Zea mays inbred lines].

Science.gov (United States)

Zhu, Yu-xi; Yang, Qun-fang; Huang, Yu-bi; Li, Qing

2015-09-01

In the present study, we investigated the systematically induced production of defense-related compounds, including DIMBOA, total phenol, trypsin inhibitors (TI) and chymotrypsin inhibitor (CI), by Tetranychus cinnabarinus infestation in Zea mays. The first leaves of two corn in-bred line seedlings, the mite-tolerant line ' H1014168' and the mite-sensitive line 'H1014591', were sucked by T. cinnabarinus adult female for seven days, and then the contents of DIMBOA, total phenol, TI and CI were measured in the second leaf and in the roots, respectively. Results showed that as compared to the unsucked control, all contents of DIMBOA, total phenol, TI and CI induced by T. cinnabarinus sucking were significantly higher in the second leaf of both inbred lines as well as in the roots of the mite-tolerant 'H1014168'. However, in the roots of 'H1014591', these defense compounds had different trends, where there was a higher induction of TI and a lower level of total phenol than that of the healthy control, while had almost no difference in DIMBOA and CI. These findings suggested that the infestation of T. cinnabarinus could systematically induce accumulation of defense-related compounds, and this effect was stronger in the mite-tolerant inbred line than in the mite-sensitive inbred line.

Gamma irradiation as a quarantine treatment for spider mites (Acarina: tetranychidae) in horticultural products

International Nuclear Information System (INIS)

Ignatowicz, S.; Banasik-Solgala, K.

1999-01-01

The carmine spider mite, Tetranychus cinnabarinus (Boisd.), and the two-spotted spider mite, Tetranychus urticae Koch, are closely related species of tetranychid mites (Acarina, Tetranychidae) that respond to gamma irradiation in a similar way. Eggs of both species exposed to gamma radiation early in embryonic development were considerably more susceptible to irradiation than older eggs. The tolerance of eggs to gamma radiation increased in 3-4-day-old eggs, when eye-spots were formed. Nymphs were more resistant to gamma radiation than eggs and larvae. Deteriorative effects of irradiation treatment were reflected in the immatures by their mortality in subsequent developmental stages. A positive relationship between dosage and the percent egg mortality or the mortality of subsequent stages was usually found when the immature stages were irradiated. The sex ratio of adults developed from irradiated eggs, larvae, and nymphs was affected by the irradiation treatment; the ratio was usually skewed towards males. Irradiation of females resulted in increased mortality, lowered fecundity, reduced egg viability, and sex ratio distortion in their progeny. Two-day-old females of the carmine spider mite and the two-spotted spider mite irradiated with 200 or 300 Gy lived as long as the controls. Mortality occurred after 3 weeks. The number of eggs laid by irradiated females of spider mites was considerably lower than in the control, and it decreased as the absorbed dose increased. The higher the dose of gamma radiation applied to adults of the spider mites (the parental generation, P), the higher the mortality of the F1 mites during their embryonic development. Viability of eggs laid by irradiated females of spider mites mated with irradiated males was significantly reduced. Young females treated with a dose of 0.2 kGy produced 40-50% nonviable eggs, while control mites produced only 6.0-6.6% nonviable eggs. A dose of 0.3 kGy caused high mortality of eggs; 88% and 97% nonviable

Meta-transcriptomics indicates biotic cross-tolerance in willow trees cultivated on petroleum hydrocarbon contaminated soil.

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Gonzalez, Emmanuel; Brereton, Nicholas J B; Marleau, Julie; Guidi Nissim, Werther; Labrecque, Michel; Pitre, Frederic E; Joly, Simon

2015-10-12

High concentrations of petroleum hydrocarbon (PHC) pollution can be hazardous to human health and leave soils incapable of supporting agricultural crops. A cheap solution, which can help restore biodiversity and bring land back to productivity, is cultivation of high biomass yielding willow trees. However, the genetic mechanisms which allow these fast-growing trees to tolerate PHCs are as yet unclear. Salix purpurea 'Fish Creek' trees were pot-grown in soil from a former petroleum refinery, either lacking or enriched with C10-C50 PHCs. De novo assembled transcriptomes were compared between tree organs and impartially annotated without a priori constraint to any organism. Over 45% of differentially expressed genes originated from foreign organisms, the majority from the two-spotted spidermite, Tetranychus urticae. Over 99% of T. urticae transcripts were differentially expressed with greater abundance in non-contaminated trees. Plant transcripts involved in the polypropanoid pathway, including phenylalanine ammonia-lyase (PAL), had greater expression in contaminated trees whereas most resistance genes showed higher expression in non-contaminated trees. The impartial approach to annotation of the de novo transcriptomes, allowing for the possibility for multiple species identification, was essential for interpretation of the crop's response treatment. The meta-transcriptomic pattern of expression suggests a cross-tolerance mechanism whereby abiotic stress resistance systems provide improved biotic resistance. These findings highlight a valuable but complex biotic and abiotic stress response to real-world, multidimensional contamination which could, in part, help explain why crops such as willow can produce uniquely high biomass yields on challenging marginal land.

The effect of synthetic pesticides and sulfur used in conventional and organically grown strawberry and soybean on Neozygites floridana, a natural enemy of spider mites.

Science.gov (United States)

Castro, Thiago; Roggia, Samuel; Wekesa, Vitalis W; de Andrade Moral, Rafael; Gb Demétrio, Clarice; Delalibera, Italo; Klingen, Ingeborg

2016-09-01

The beneficial fungus Neozygites floridana kills the two-spotted spider mite Tetranychus urticae, which is a serious polyphagous plant pest worldwide. Outbreaks of spider mites in strawberry and soybean have been associated with pesticide applications. Pesticides may affect N. floridana and consequently the natural control of T. urticae. N. floridana is a fungus difficult to grow in artificial media, and for this reason, very few studies have been conducted with this fungus, especially regarding the impact of pesticides. The aim of this study was to conduct a laboratory experiment to evaluate the effect of pesticides used in strawberry and soybean crops on N. floridana. Among the pesticides used in strawberry, the fungicides sulfur and cyprodinil + fludioxonil completely inhibited both the sporulation and conidial germination of N. floridana. The fungicide fluazinam affected N. floridana drastically. The application of the fungicide tebuconazole and the insecticides fenpropathrin and abamectin resulted in a less pronounced negative effect on N. floridana. Except for epoxiconazole and cyproconazole, all tested fungicides used in soybean resulted in a complete inhibition of N. floridana. Among the three insecticides used in soybean, lambda-cyhalothrin and deltamethrin resulted in a significant inhibition of N. floridana. The insecticides/ acaricides abamectin and lambda-cyhalothrin at half concentrations and fenpropathrin and permethrin and the fungicide tebuconazole at the recommended concentrations resulted in the lowest impact on N. floridana. The fungicides with the active ingredients sulfur, cyprodinil + fludioxonil, azoxystrobin, azoxystrobin + cyproconazole, trifloxystrobin + tebuconazole and pyraclostrobin + epoxiconazole negatively affected N. floridana. © 2015 Society of Chemical Industry. © 2015 Society of Chemical Industry.

Synthesis and characterization of an effective organic/inorganic hybrid green corrosion inhibitive complex based on zinc acetate/Urtica Dioica

International Nuclear Information System (INIS)

Salehi, E.; Naderi, Reza; Ramezanzadeh, B.

2017-01-01

Highlights: • An organic/inorganic hybrid green corrosion inhibitive pigment was synthesized and characterized. • Chemical structure and morphology of the hybrid complex were characterized. • Zinc acetate/Urtica Dioica showed effective inhibition action in saline solution on carbon steel. • The synergistic effect between Zn 2+ cations and inhibitive compounds existed in U.D resulted in protective film deposition on the steel surface. - Abstract: This study aims at synthesis and characterization of an effective corrosion inhibitive complex based on zinc acetate/Urtica Dioica (ZnA-U.D) for corrosion protection of mild steel in chloride solution. The chemical structure and morphology of the complex were characterized by Fourier transform infrared spectroscopy (FT-IR), UV–vis, thermal gravimetric analysis (TGA), X-ray photoelectron spectroscopy (XPS) and scanning electron microscopy (SEM). The corrosion protection performance of the mild steel samples dipped in 3.5 wt.% NaCl solutions with and without ZnA-U.D extract was investigated by visual observations, open circuit potential (OCP) measurements, electrochemical impedance spectroscopy (EIS) and polarization test. Results revealed that the ZnA successfully chelated with organic inhibitive compounds (i.e Quercetin, Quinic acid, Caffeic acid, Hystamine and Serotonin) present in the U.D extract. The electrochemical measurements revealed the effective inhibition action of ZnA-U.D complex in the sodium chloride solution on the mild steel. The synergistic effect between Zn 2+ and organic compounds present in the U.D extract resulted in protective film deposition on the steel surface, which was proved by SEM and XPS analyses.

Synthesis and characterization of an effective organic/inorganic hybrid green corrosion inhibitive complex based on zinc acetate/Urtica Dioica

Energy Technology Data Exchange (ETDEWEB)

Salehi, E.; Naderi, Reza [School of Metallurgy and Materials Engineering, College of Engineering, University of Tehran, P.O. Box 11155-4563, Tehran (Iran, Islamic Republic of); Ramezanzadeh, B., E-mail: ramezanzadeh@aut.ac.ir [Department of Surface Coatings and Corrosion, Institute for Color Science and Technology (ICST), PO 16765-654, Tehran (Iran, Islamic Republic of)

2017-02-28

Highlights: • An organic/inorganic hybrid green corrosion inhibitive pigment was synthesized and characterized. • Chemical structure and morphology of the hybrid complex were characterized. • Zinc acetate/Urtica Dioica showed effective inhibition action in saline solution on carbon steel. • The synergistic effect between Zn{sup 2+} cations and inhibitive compounds existed in U.D resulted in protective film deposition on the steel surface. - Abstract: This study aims at synthesis and characterization of an effective corrosion inhibitive complex based on zinc acetate/Urtica Dioica (ZnA-U.D) for corrosion protection of mild steel in chloride solution. The chemical structure and morphology of the complex were characterized by Fourier transform infrared spectroscopy (FT-IR), UV–vis, thermal gravimetric analysis (TGA), X-ray photoelectron spectroscopy (XPS) and scanning electron microscopy (SEM). The corrosion protection performance of the mild steel samples dipped in 3.5 wt.% NaCl solutions with and without ZnA-U.D extract was investigated by visual observations, open circuit potential (OCP) measurements, electrochemical impedance spectroscopy (EIS) and polarization test. Results revealed that the ZnA successfully chelated with organic inhibitive compounds (i.e Quercetin, Quinic acid, Caffeic acid, Hystamine and Serotonin) present in the U.D extract. The electrochemical measurements revealed the effective inhibition action of ZnA-U.D complex in the sodium chloride solution on the mild steel. The synergistic effect between Zn{sup 2+} and organic compounds present in the U.D extract resulted in protective film deposition on the steel surface, which was proved by SEM and XPS analyses.

Antioxidant and antimicrobial activity in the seeds of Origanum vulgare L. subsp. gracile (C. Koch Ietswaart and Origanum acutidens (Hand.-Mazz. Ietswaart from Turkey

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Erecevit, P.

2011-12-01

Full Text Available The present study determined some biological compounds (fatty acids, vitamins, sterols and flavonoids, radical scavenging capacity and antimicrobial activity of two Origanum L. species of Origanum vulgare L. subsp. gracile (C. Koch Ietswaart and Origanum acutidens (Hand.-Mazz.. Ietswaart. Linolenic acid was found to be the main fatty acid in both species, which was followed by palmitic acid (C16:0, stearic acid (C18:0, oleic acid (C18:1 n9, linoleic acid (C18:2 n6 and stearidonic acid (C18:4. In addition, the two Origanum species were recorded as containing high levels of stigmasterol. It was also found that Origanum vulgare L. subsp. gracile (C. Koch Ietswaart had a high β-sitosterol content (152.8±2.6 µg/g; high amounts of D3 (33.1±0.8 µg/g, K1 (29.4±0.8 µg/g, K2 (26.0±0.8 µg/g vitamins; and low amounts of α-tocopherol (7.8±0.2 µg/g and D2 (1.8±0.1 µg/g, while Origanum acutidens (Hand.-Mazz. Ietswaart contained high amounts of D2 (42.9±1.5 µg/g vitamin; and low amounts of D3 (2.9±0.1 µg/g, α-tocopherol (3.1±0.1 µg/g, r-tocopherol (3.5±0.2 µg/g, K2 (1.3±0.1 µg/g, retinol (1.3±0.2 µg/g and retinol acetate (1.2±0.1 µg/g vitamins. The present study showed that Origanum vulgare L. subsp. gracile (C. Koch Ietswaart and Origanum acutidens (Hand.-Mazz. Ietswaart contained the lowest amount of flavonoid. Furthermore, methanol extracts were recorded to be the most effective agent against the DPPH radical in both Origanum L. species examined. Experimental results showed that the vitamins, flavonoids and fatty acid extracts of both Origanum L. species were effective in the inhibition of the growth of the tested microorganisms at varying levels.En el presente estudio se han determinado algunos compuestos biológicos (ácidos grasos, vitaminas, esteroles y flavonoides, la capacidad de secuestrar radicales libres y la actividad antimicrobiana de dos especies de orégano, Origanum vulgare L. subsp. gracile (C. Koch Ietswaart y

Sigmund Freud and the Crick-Koch hypothesis. A footnote to the history of consciousness studies.

Science.gov (United States)

Smith, D L

1999-06-01

The author describes Crick and Koch's recently developed theory of the neurophysiological basis of consciousness as synchronised neural oscillations. The thesis that neural oscillations provide the neurophysiological basis for consciousness was anticipated by Sigmund Freud in his 1895 'Project for a scientific psychology'. Freud attempted to solve his neuropsychological 'problem of quality' by means of the hypothesis that information concerning conscious sensory qualities is transmitted through the mental apparatus by means of neural 'periods'. Freud believed that information carried by neural oscillations would proliferate across 'contact-barriers' (synapses) without inhibition. Freud's theory thus appears to imply that synchronised neural oscillations are an important component of the neurophysiological basis of consciousness. It is possible that Freud's thesis was developed in response to the experimental research of the American neuroscientist M. M. Garver.

Exploring the Urtica dioica Leaves Hemostatic and Wound-Healing Potential.

Science.gov (United States)

Zouari Bouassida, Karama; Bardaa, Sana; Khimiri, Meriem; Rebaii, Tarek; Tounsi, Slim; Jlaiel, Lobna; Trigui, Mohamed

2017-01-01

The present paper investigated the efficiency of Urtica dioica (U. dioica) on hemostatic and wound healing activities. U. dioica leaf extracts were evaluated for their antibacterial and antioxidant effects as well as their flavonoid and polyphenol content. The hydroethanolic extract (EtOH-H 2 OE), showing the most potent antibacterial and antioxidant activities in vitro , thanks to its flavonoid and polyphenol richness, was selected for hemostatic and wound healing evaluation. Twenty-four rats completing full-thickness wounds were split into four groups. The wounds were topically treated with saline solution, glycerol, "CICAFLORA," and U. dioica EtOH-H 2 OE (50  µ L/mm 2 ) until day 11. The wound healing effect was assessed by macroscopic, histological, and biochemical parameters. Rats treated with EtOH-H 2 OE showed fast wound closure (92.39%) compared to the control animals (60.91%) on the 11th day of wounding ( P dioica EtOH-H 2 OE treated rats. Analysis of fatty acids and sterols by GC-MS showed the presence of unsaturated fatty acids and a high concentration of lupeol known for their involvement in reepithelialization. These results prove the efficiency of U. dioica EtOH-H 2 OE in wound healing and supported its traditional use.

Characterization of Urtica dioica agglutinin isolectins and the encoding gene family.

Science.gov (United States)

Does, M P; Ng, D K; Dekker, H L; Peumans, W J; Houterman, P M; Van Damme, E J; Cornelissen, B J

1999-01-01

Urtica dioica agglutinin (UDA) has previously been found in roots and rhizomes of stinging nettles as a mixture of UDA-isolectins. Protein and cDNA sequencing have shown that mature UDA is composed of two hevein domains and is processed from a precursor protein. The precursor contains a signal peptide, two in-tandem hevein domains, a hinge region and a carboxyl-terminal chitinase domain. Genomic fragments encoding precursors for UDA-isolectins have been amplified by five independent polymerase chain reactions on genomic DNA from stinging nettle ecotype Weerselo. One amplified gene was completely sequenced. As compared to the published cDNA sequence, the genomic sequence contains, besides two basepair substitutions, two introns located at the same positions as in other plant chitinases. By partial sequence analysis of 40 amplified genes, 16 different genes were identified which encode seven putative UDA-isolectins. The deduced amino acid sequences share 78.9-98.9% identity. In extracts of roots and rhizomes of stinging nettle ecotype Weerselo six out of these seven isolectins were detected by mass spectrometry. One of them is an acidic form, which has not been identified before. Our results demonstrate that UDA is encoded by a large gene family.

Interspecific competition counteracts negative effects of dispersal on adaptation of an arthropod herbivore to a new host.

Science.gov (United States)

Alzate, A; Bisschop, K; Etienne, R S; Bonte, D

2017-11-01

Dispersal and competition have both been suggested to drive variation in adaptability to a new environment, either positively or negatively. A simultaneous experimental test of both mechanisms is however lacking. Here, we experimentally investigate how population dynamics and local adaptation to a new host plant in a model species, the two-spotted spider mite (Tetranychus urticae), are affected by dispersal from a stock population (no-adapted) and competition with an already adapted spider mite species (Tetranychus evansi). For the population dynamics, we find that competition generally reduces population size and increases the risk of population extinction. However, these negative effects are counteracted by dispersal. For local adaptation, the roles of competition and dispersal are reversed. Without competition, dispersal exerts a negative effect on adaptation (measured as fecundity) to a novel host and females receiving the highest number of immigrants performed similarly to the stock population females. By contrast, with competition, adding more immigrants did not result in a lower fecundity. Females from populations with competition receiving the highest number of immigrants had a significantly higher fecundity than females from populations without competition (same dispersal treatment) and than the stock population females. We suggest that by exerting a stronger selection on the adapting populations, competition can counteract the migration load effect of dispersal. Interestingly, adaptation to the new host does not significantly reduce performance on the ancestral host, regardless of dispersal rate or competition. Our results highlight that assessments of how species can adapt to changing conditions need to jointly consider connectivity and the community context. © 2017 The Authors. Journal of Evolutionary Biology Published by John Wiley & Sons ltd on Behalf of European Society for Evolutionary Biology.

Chemical composition and in vitro cytotoxic, genotoxic effects of essential oil from Urtica dioica L.

Science.gov (United States)

Gül, Süleyman; Demirci, Betül; Başer, Kemal Hüsnü Can; Akpulat, H Aşkin; Aksu, Pinar

2012-05-01

The aim of this study was to determine the chemical composition of Urtica dioica essential oil, and to evaluate its cytotoxic and genotoxic effects, using cytogenetic tests such as the cytokinesis-block micronucleus assay and chromosomal aberration analysis in human lymphocyte cultures in vitro. GC-MS analysis of U. dioica essential oil identified 43 compounds, representing 95.8% of the oil. GC and GC-MS analysis of the essential oil of U. dioica revealed that carvacrol (38.2%), carvone (9.0%), naphthalene (8.9%), (E)-anethol (4.7%), hexahydrofarnesyl acetone (3.0%), (E)-geranyl acetone (2.9%), (E)-β-ionone (2.8%) and phytol (2.7%) are the main components, comprising 72.2% of the oil. A significant correlation was found between the concentration of essential oil and the following: chromosomal aberrations, micronuclei frequency, apoptotic cells, necrotic cells, and binucleated cells.

[Analysis of Koch phenomenon of Mycobacterium tuberculosis-infected guinea pigs vaccinated with recombinant tuberculosis vaccine AEC/BC02].

Science.gov (United States)

Lu, J B; Cheng, B W; Deng, H Q; Su, C; Shen, X B; Du, W X; Yang, L; Wang, G Z; Xu, M

2016-07-01

To observe the Koch phenomenon of Mycobacterium tuberculosis(MTB)-infected guinea pigs after vaccinated with killed H37Ra bacteria or tuberculosis vaccine candidate AEC/BC02. Eighteen guinea pigs were challenged subcutaneously with 5.0×10(3) CFU MTB and after 40 days were divided into 3 groups (6 per group): NS group, AEC/BC02 group and H37Ra group, which were injected intramuscularly 3 times at 1 day interval with normal saline, AEC/BC02 vaccine and killed H37Ra bacteria respectively. Three weeks after the first vaccination, all guinea pigs were sacrificed to evaluate gross pathological scores for liver, spleen and lung, bacterial loads in lung and spleen, and lung inflammation. The gross pathological score in H37Ra group (48±26) was lower than that in NS group(62±15), but the difference was not significant (t=1.093, P=0.300). The AEC/BC02 group had a significantly lower gross pathological score (36±15) than NS group (t=2.980, P=0.014). No significant difference between H37Ra group and AEC/BC02 group was observed (t=1.009, P=0.337). The spleen bacterial load [(5.31±0.80) log10 CFU]in H37Ra group was slightly lower than that in NS group[(5.57±0.75) log10 CFU] but the difference was not significant (t=1.581, P=0.574). In AEC/BC02 group bacterial load in the spleen was (4.64±0.64) log10 CFU and significantly lower than NS group (t=2.306, P=0.044) and no significant difference between H37Ra group and AEC/BC02 group was observed (t=1.602, P=0.140). Meanwhile, the lung bacterial load in AEC/BC02 group was (3.71±1.01) log10 CFU and in H37Ra group was (3.82±1.25) log10 CFU. Compared to (4.15±0.69) log10 CFU in the NS group, no significant differences were found (t=0.881, P=0.399; t=0.566, P=0.584, respectively). For the lung inflammation, the inflamed areas in H37Ra group were significantly larger [(33.0±4.4%)] than those in both NS group [(14.8±8.4) %, t=4.719, P=0.001] and AEC/BC02 group [(14.8±8.4) %, t=3.616, P=0.005], and no significant differences were

Sweepoviruses cause disease in sweet potato and related Ipomoea spp.: fulfilling Koch's postulates for a divergent group in the genus begomovirus.

Science.gov (United States)

Trenado, Helena P; Orílio, Anelise F; Márquez-Martín, Belén; Moriones, Enrique; Navas-Castillo, Jesús

2011-01-01

Sweet potato (Ipomoea batatas) and related Ipomoea species are frequently infected by monopartite begomoviruses (genus Begomovirus, family Geminiviridae), known as sweepoviruses. Unlike other geminiviruses, the genomes of sweepoviruses have been recalcitrant to rendering infectious clones to date. Thus, Koch's postulates have not been fullfilled for any of the viruses in this group. Three novel species of sweepoviruses have recently been described in Spain: Sweet potato leaf curl Lanzarote virus (SPLCLaV), Sweet potato leaf curl Spain virus (SPLCSV) and Sweet potato leaf curl Canary virus (SPLCCaV). Here we describe the generation of the first infectious clone of an isolate (ES:MAL:BG30:06) of SPLCLaV. The clone consisted of a complete tandem dimeric viral genome in a binary vector. Successful infection by agroinoculation of several species of Ipomoea (including sweet potato) and Nicotiana benthamiana was confirmed by PCR, dot blot and Southern blot hybridization. Symptoms observed in infected plants consisted of leaf curl, yellowing, growth reduction and vein yellowing. Two varieties of sweet potato, 'Beauregard' and 'Promesa', were infected by agroinoculation, and symptoms of leaf curl and interveinal loss of purple colouration were observed, respectively. The virus present in agroinfected plants was readily transmitted by the whitefly Bemisia tabaci to I. setosa plants. The progeny virus population present in agroinfected I. setosa and sweet potato plants was isolated and identity to the original isolate was confirmed by sequencing. Therefore, Koch's postulates were fulfilled for the first time for a sweepovirus.

Sweepoviruses cause disease in sweet potato and related Ipomoea spp.: fulfilling Koch's postulates for a divergent group in the genus begomovirus.

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Helena P Trenado

Full Text Available Sweet potato (Ipomoea batatas and related Ipomoea species are frequently infected by monopartite begomoviruses (genus Begomovirus, family Geminiviridae, known as sweepoviruses. Unlike other geminiviruses, the genomes of sweepoviruses have been recalcitrant to rendering infectious clones to date. Thus, Koch's postulates have not been fullfilled for any of the viruses in this group. Three novel species of sweepoviruses have recently been described in Spain: Sweet potato leaf curl Lanzarote virus (SPLCLaV, Sweet potato leaf curl Spain virus (SPLCSV and Sweet potato leaf curl Canary virus (SPLCCaV. Here we describe the generation of the first infectious clone of an isolate (ES:MAL:BG30:06 of SPLCLaV. The clone consisted of a complete tandem dimeric viral genome in a binary vector. Successful infection by agroinoculation of several species of Ipomoea (including sweet potato and Nicotiana benthamiana was confirmed by PCR, dot blot and Southern blot hybridization. Symptoms observed in infected plants consisted of leaf curl, yellowing, growth reduction and vein yellowing. Two varieties of sweet potato, 'Beauregard' and 'Promesa', were infected by agroinoculation, and symptoms of leaf curl and interveinal loss of purple colouration were observed, respectively. The virus present in agroinfected plants was readily transmitted by the whitefly Bemisia tabaci to I. setosa plants. The progeny virus population present in agroinfected I. setosa and sweet potato plants was isolated and identity to the original isolate was confirmed by sequencing. Therefore, Koch's postulates were fulfilled for the first time for a sweepovirus.

Experimental infestation with the immatures of Amblyomma dissimile Koch, 1844 (Acari: Ixodidae on Tropidurus torquatus (Lacertilia: Iguanidae and Oryctolagus cuniculus Infestação experimental com as fases imaturas de Amblyomma dissimile Koch, 1844 (Acari: Ixodidae em Tropidurus torquatus (Lacertilia: Iguanidae e Oryctolagus cuniculus

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L.H.T. Freitas

2004-02-01

Full Text Available Larvas provenientes de duas fêmeas de Amblyomma dissimile Koch, 1844 (Acari: Ixodidae, naturalmente ingurgitadas em uma iguana (Iguana iguana e provenientes do Estado do Mato Grosso, foram utilizadas na infestação experimental de lagartos da espécie Tropidurus torquatus e coelhos domésticos. As larvas alimentadas em ambos os hospedeiros realizaram ecdise para ninfas. As ninfas apenas ingurgitaram no lagarto e mudaram para machos e fêmeas. Este é o primeiro registro do parasitismo de larvas e ninfas de A. dissimile em T. torquatus e de larvas em coelhos.

A Modular Cage System Design for Continuous Medium to Large Scale In Vivo Rearing of Predatory Mites (Acari: Phytoseiidae

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Juan Alfredo Morales-Ramos

2014-01-01

Full Text Available A new stackable modular system was developed for continuous in vivo production of phytoseiid mites. The system consists of cage units that are filled with lima beans,  Phaseolus lunatus, or red beans, P. vulgaris, leaves infested with high levels of the two-spotted spider mites, Tetranychus urticae. The cage units connect with each other through a connection cup, which also serves for monitoring and collection. Predatory mites migrate upwards to new cage units as prey is depleted. The system was evaluated for production of Phytoseiulus persimilis. During a 6-month experimental period, 20,894.9±10,482.5 (mean ± standard deviation predators were produced per week. The production consisted of 4.1±4.6% nymphs and 95.9±4.6% adults. A mean of 554.5±59.8 predatory mites were collected per harvested cage and the mean interval length between harvests was 6.57±6.76 days. The potential for commercial and experimental applications is discussed.

Higher glandular trichome density in tomato leaflets and repellence to spider mites

International Nuclear Information System (INIS)

Maluf, Wilson Roberto; Inoue, Irene Fumi; Ferreira, Raphael de Paula Duarte; Gomes, Luiz Antonio Augusto; Castro, Evaristo Mauro de; Cardoso, Maria das Gracas

2007-01-01

The objective of this work was to evaluate the feasibility of selection for higher glandular trichome densities, as an indirect criterion of selection for increasing repellence to spider mites Tetranychus urticae, in tomato populations derived from an interspecific cross between Lycopersicon esculentum x L. hirsutum var. glabratum PI 134417. Trichome densities were evaluated in 19 genotypes, including 12 from advanced backcross populations, derived from the original cross L. esculentum x L. hirsutum var. glabratum PI 134417. Counts were made both on the adaxial and abaxial leaf surfaces, and trichomes were classified into glandular types IV and VI, other glandular types (types I+VII), and nonglandular types. Mite repellence was measured by distances walked by mites onto the tomato leaf surface after 20, 40 and 60 min. Spider mite repellence biotests indicated that higher densities of glandular trichomes (especially type VI) decreased the distances walked by the mites onto the tomato leaf surface. Selection of plants with higher densities of glandular trichomes can be an efficient criterion to obtain tomato genotypes with higher resistance (repellence) to spider mites. (author)

Study of stinging nettle (urtica dioica l.) Fibers reinforced green composite materials : a review

Science.gov (United States)

Agus Suryawan, I. G. P.; Suardana, N. P. G.; Suprapta Winaya, I. N.; Budiarsa Suyasa, I. W.; Tirta Nindhia, T. G.

2017-05-01

Stinging Nettle (Urtica dioica L., latin) is a wild plant that grows in Indonesia, Asia, and Europe. Nettle in Bali, Indonesia is called as Lateng, Jelatang. Nettle plant has a very strong fiber and high fixed carbon. Nettle plants are covered with fine hairs, especially in the leaves and stems. When it is touched, it will release chemicals, sting and trigger inflammation that causes redness, itching, bumps and irritation to the skin. Nettle plants grow in the wild, regarded as a weed in the agricultural industry, easy to grow and snatch food from the parent plant. The main objective of this paper is to review of the potential nettle fibers and then explain about the potential of local nettle plant in Indonesia. Nettle is a plant group at the end of bast. Its plant fibers taken from the bark, as reinforcement in composite materials. Nettle fibers have three main advantages such as strong, lightweight and low environmental impact.

Comparative study of the UV spectra of various raw materials OF Urtica dioica L.

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E. A. Balagozyan

2016-01-01

Full Text Available Stinging nettle (Urtica dioica L. is one of the famous and popular medicinal plants. In Russia the herbal materials are nettle’s leaves which have haemostatic effect. At the same time abroad the rhizomes and roots of nettle are the source of drugs with antitumor activity. The chemical composition of the rhizomes and roots of nettle is quite complicated and is represented by substances such as polysaccharides, lectins, sterols etc. The aim of the present study is the comparative phytochemical research of various parts of raw nettle by spectrophotometry. The study of extracts from various raw materials of nettle has shown, that the presence of flavonoids is peculiar for leaves, flowers and fruits. Sterols dominate in the rhizomes and roots of nettle. It was also noted that the UV-spectra of extracts of female inflorescences and fruits nettle have the same absorption maxima.

Salix transect of Europe: variation in ploidy and genome size in willow-associated common nettle, Urtica dioica L. sens. lat., from Greece to arctic Norway

OpenAIRE

Quentin Cronk; Oriane Hidalgo; Jaume Pellicer; Diana Percy; Ilia Leitch

2016-01-01

Abstract Background The common stinging nettle, Urtica dioica L. sensu lato, is an invertebrate "superhost", its clonal patches maintaining large populations of insects and molluscs. It is extremely widespread in Europe and highly variable, and two ploidy levels (diploid and tetraploid) are known. However, geographical patterns in cytotype variation require further study. New information We assembled a collection of nettles in conjunction with a transect of Europe from the Aegean to Arctic No...

Rezension zu: Angela Koch: Ir/Reversible Bilder. Zur Visualisierung und Medialisierung von sexueller Gewalt. Berlin: Verlag Vorwerk 8 2015.

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Katarina Saalfeld

2016-06-01

Full Text Available Angela Koch legt eine umfangreiche Betrachtung der Darstellbarkeit von sexueller Gewalt in den Bildmedien Film, Fernsehen und Fotografie vor. Indem sie theoretische Positionen des Poststrukturalismus mit konkreten Film- und Bildanalysen konfrontiert, zeigt sie auf, dass den Möglichkeiten der (Audio-Visualisierung sexueller Gewalt Grenzen gesetzt sind. Über die Herstellung und Bedienung ästhetischer Konventionen wird ein normiertes Wissen über sexuelle Gewalt hergestellt, das die hegemoniale Geschlechterordnung unterstützt und aufrechterhält. Während auch grenzüberschreitende Momente der Darstellbarkeit aufgespürt werden, liegt das Hauptgewicht der Studie auf der Kritik des medial vermittelten Geschlechterverhältnisses als Gewaltverhältnis.

Role of cucurbitacin C in resistance to spider mite (Tetranychus urticae) in cucumber (Cucumber sativus L.)

NARCIS (Netherlands)

Balkema-Boomstra, A.G.; Zijlstra, S.; Verstappen, F.W.A.; Inggamer, H.; Mercke, P.

2003-01-01

Cucurbitacins are bitter triterpenoid compounds that are toxic to most organisms and occur widely in wild and cultivated Cucurbitaceae. The only cucurbitacin identified in Cucumis sativus is cucurbitacin C. The bitter taste of cucumber has been correlated with resistance to the spider mite

Evaluación de la resistencia a los sulfates de cemento con ceniza volante (utilizando el método de Koch & Steinegger)

OpenAIRE

Irassar, Edgardo F.; Sota, Jorge D.; Batic, Oscar R.

1988-01-01

El aumento del consumo de las adiciones minerales activas en los materiales cementíceos contemporáneos ha determinado la revisión de algunos métodos de ensayo utilizados para determinar sus propiedades. En la evaluación de la durabilidad de los cementos compuestos, muchos ensayos de corta duración (de gran aplicación en cementos portland) dejan de tener validez, pues no permiten evaluar las mejoras que producen los materiales puzolánicos. El método propuesto por KOCH...

Sulfate resistance evaluation of the cement with fly ash (using the Koch & Steinegger method

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Irassar, Edgardo F.

1988-12-01

Full Text Available The increase of active mineral admixtures consumption in contemporaneous cementiceous materials has stablished revision of some test methods. In the evaluation of blended cement durability, many accelerated tests of large application in portland cements become unvalid, because they don't allow to value the improvements produced by pozzolan materials. Koch-Steinegger Method appears as the most appropiate to evaluate sulfate resistance of cement with active mineral admixtures. In this paper are presented the results obtained with this test in the evaluation of an ordinary portland cement (CPN and one resisting sulfates (CPARS, with low calcium fly ash addition. Fly ash is incorporated with three fineness (280, 420 and 480 m²/Kg Blaine. The results show that this addition improves sulfate resistance of CPN and in minor way of ARS cement. Fly ash influences evolution of mechanical strength in water and chemical resistance at first ages.

El aumento del consumo de las adiciones minerales activas en los materiales cementíceos contemporáneos ha determinado la revisión de algunos métodos de ensayo utilizados para determinar sus propiedades. En la evaluación de la durabilidad de los cementos compuestos, muchos ensayos de corta duración (de gran aplicación en cementos portland dejan de tener validez, pues no permiten evaluar las mejoras que producen los materiales puzolánicos. El método propuesto por KOCH & STEINEGGER (1960 aparece como uno de los más apropiados para determinar el comportamiento de cementos con adiciones minerales activas frente al ataque de sulfatos. En este trabajo se presentan los resultados alcanzados con ente ensayo en la determinación del comportamiento de un cemento portland normal (CRN y uno resistente a los sulfatos (CPARS, adicionados con ceniza volante de bajo contenido en óxido de calcio. La ceniza se incorpora con tres finuras (280, 420 y 480 m²/kg —Blaine—. Estos

Eficiência do óxido de fenbutatin sobre formas móveis do ácaro vermelho europeu (Panonychus ulmi Koch. em macieira Efficience evaluation of fenbutatin oxide on control of red mite (Panonychus ulmi Koch. on apple tree

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Ivan Francisco Dressler da Costa

1997-06-01

Full Text Available O objetivo deste experimento foi avaliar a eficiência do Óxido de Fenbutatin, no controle das formas móveis do ácaro vermelho europeu. Realizou-se um ensaio em pomar de macieira, cv. Fuji, na Empresa Florense, em Lagoa Vermelha, RS, na safra de 1993/94. Os resultados demonstraram que todas as doses utilizadas foram eficientes, até os trinta dias após a aplicação.The objective of this experiment was to evaluate the efficience of Fenbutatin Oxide for controlling mobile forms of red mite ( Panonichus ulmi Koch.. An experiment was conducted in apple orchard cv. Fuji, in Lagoa Vermelha county, RS, Brazil, in 1993/94. The results indicated that all treatments with Fenbutatin Oxide were efficients at 30 days after application.

Antioxidant properties of soybean seedlings inoculated with Trichoderma asperellum

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Manojlović Ana S.

2017-01-01

Full Text Available This study was conducted in order to assess the effect of inoculation of soybean (Glycine max L. seeds with Trichoderma asperellum, followed by mites (Tetranychus urticae exposure on lipid peroxidation (LP process and the activity of antioxidant enzymes. T. urticae is an occasional pest of soybean that causes biotic stress. Biotic stress leads to overproduction of reactive oxygen species (ROS which may cause damage to vital biomolecules. Enzymatic antioxidant defense systems protect plants against oxidative stress. T. asperellum is commonly used as biocontrol agent against plant pathogens. It has been suggested that previous inoculation of seeds with T. asperellum may cause induced resistance against biotic stress. The aim of this study was to determine LP intensity and antioxidant enzymes activity in inoculated and non-inoculated soybean seedlings with and without exposure to mites. Noticeably higher LP intensity was detected in non-inoculated group treated with mites compared to control group. Inoculated soybean seedlings treated with mites had lower LP intensity compared to noninoculated group. Also, it has been noticed that inoculation with Trichoderma asperellum itself, produced mild stress in plants. In addition, positive correlation between enzymes activity and LP was noticed. The level of oxidative stress in plants was followed by the change of LP intensity. According to results obtained, it was concluded that the greatest oxidative stress occurred in non-inoculated group treated with mites and that inoculation successfully reduced oxidative stress. The results indicate that inoculation of soybean seeds with T. asperellum improves resistance of soybean seedlings against mites attack. [Project of the Serbian Ministry of Education, Science and Technological Development, Grant no. TR-31022

Induction of direct and indirect plant responses by jasmonic acid, low spider mite densities, or a combination of jasmonic acid treatment and spider mite infestation.

Science.gov (United States)

Gols, Rieta; Roosjen, Mara; Dijkman, Herman; Dicke, Marcel

2003-12-01

Jasmonic acid (JA) and the octadecanoid pathway are involved in both induced direct and induced indirect plant responses. In this study, the herbivorous mite, Tetranychus urticae, and its predator, Phytoseiulus persimilis, were given a choice between Lima bean plants induced by JA or spider mites and uninduced control plants. Infestation densities resulting in the induction of predator attractants were much lower than thus far assumed, i.e., predatory mites were significantly attracted to plants that were infested for 2 days with only one or four spider mites per plant. Phytoseiulus persimilis showed a density-dependent response to volatiles from plants that were infested with different numbers of spider mites. Similarly, treating plants with increasing concentrations of JA also led to increased attraction of P. persimilis. Moreover, the duration of spider mite infestation was positively correlated with the proportion of predators that were attracted to mite-infested plants. A pretreatment of the plants with JA followed by a spider mite infestation enhanced the attraction of P. persimilis to plant volatiles compared to attraction to volatiles from plants that were only infested with spider mites and did not receive a pretreatment with JA. The herbivore, T. urticae preferred leaf tissue that previously had been infested with conspecifics to uninfested leaf tissue. In the case of choice tests with JA-induced and control leaf tissue, spider mites slightly preferred control leaf tissue. When spider mites were given a choice between leaf discs induced by JA and leaf discs damaged by spider mite feeding, they preferred the latter. The presence of herbivore induced chemicals and/or spider mite products enhanced settlement of the mites, whereas treatment with JA seemed to impede settlement.

Stinging Nettle (Urtica dioica L.) Attenuates FFA Induced Ceramide Accumulation in 3T3-L1 Adipocytes in an Adiponectin Dependent Manner.

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Obanda, Diana N; Zhao, Peng; Richard, Allison J; Ribnicky, David; Cefalu, William T; Stephens, Jacqueline M

2016-01-01

Excess dietary lipids result in the accumulation of lipid metabolites including ceramides that can attenuate insulin signaling. There is evidence that a botanical extract of Urtica dioica L. (stinging nettle) improves insulin action, yet the precise mechanism(s) are not known. Hence, we examined the effects of Urtica dioica L. (UT) on adipocytes. We investigated the effects of an ethanolic extract of UT on free fatty acid (palmitic acid) induced inhibition of insulin-stimulated Akt serine phosphorylation and modulation of ceramidase expression in 3T3-L1 adipocytes. Adipocytes were exposed to excess FFAs in the presence or absence of UT. Effects on adiponectin expression, ceramidase expression, ceramidase activity, ceramide accumulation and insulin signaling were determined. As expected, FFAs reduced adiponectin expression and increased the expression of ceramidase enzymes but not their activity. FFA also induced the accumulation of ceramides and reduced insulin-stimulated phosphorylation of Akt in adipocytes. The effects of FFA were partially reversed by UT. UT enhanced adiponectin expression and ceramidase activity in the presence of excess FFAs. UT abated ceramide accumulation and increased insulin sensitivity via enhanced Akt phosphorylation. A siRNA knockdown of adiponectin expression prevented UT from exerting positive effects on ceramidase activity but not Akt phosphorylation. In adipocytes, the ability of UT to antagonize the negative effects of FFA by modulating ceramidase activity and ceramide accumulation is dependent on the presence of adiponectin. However, the ability of UT to enhance Akt phosphorylation is independent of adiponectin expression. These studies demonstrate direct effects of UT on adipocytes and suggest this botanical extract is metabolically beneficial.

Review of the comb-tailed spider genus Hahnia C.L. Koch 1841 (Hahniidae) from Gaoligong Mountains in Yunnan, China.

Science.gov (United States)

Huang, Gui-Qiang; Zhang, Zhi-Sheng; Liu, Ying-Hong

2017-11-08

Gaoligong Mountains in Yunnan, China are famous for the biodiversity and are part of Indo-Burmese hotspot. We present a review on the comb-tailed spider genus Hahnia C.L. Koch 1841 based on newly collected specimens. Four new species of Hahnia are described: H. biapophysis sp. nov. (male), H. dongi sp. nov. (male), H. subsaccata sp. nov. (male, female) and H. wangi sp. nov. (male, female). Two additional known species are redescribed: H. himalayaensis Hu & Zhang, 1990 and H. musica Brignoli, 1978. Hahnia musica previously known from Bhutan is recorded from China for the first time. Photos of habitus and genitalia of all species and additionally illustrations of new species are given.

Higher glandular trichome density in tomato leaflets and repellence to spider mites Alta densidade de tricomas glandulares em tomateiro e aumento da repelência a ácaros rajados

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Wilson Roberto Maluf

2007-09-01

Full Text Available The objective of this work was to evaluate the feasibility of selection for higher glandular trichome densities, as an indirect criterion of selection for increasing repellence to spider mites Tetranychus urticae, in tomato populations derived from an interspecific cross between Lycopersicon esculentum x L. hirsutum var. glabratum PI 134417. Trichome densities were evaluated in 19 genotypes, including 12 from advanced backcross populations, derived from the original cross L. esculentum x L. hirsutum var. glabratum PI 134417. Counts were made both on the adaxial and abaxial leaf surfaces, and trichomes were classified into glandular types IV and VI, other glandular types (types I+VII, and nonglandular types. Mite repellence was measured by distances walked by mites onto the tomato leaf surface after 20, 40 and 60 min. Spider mite repellence biotests indicated that higher densities of glandular trichomes (especially type VI decreased the distances walked by the mites onto the tomato leaf surface. Selection of plants with higher densities of glandular trichomes can be an efficient criterion to obtain tomato genotypes with higher resistance (repellence to spider mites.O objetivo deste trabalho foi avaliar a eficiência da seleção para maior densidade de tricomas glandulares na resistência (repelência ao ácaro Tetranychus urticae, em populações de tomate derivadas do cruzamento interespecífico Lycopersicon esculentum x L. hirsutum var. glabratum PI 134417. Foram avaliados 19 genótipos quanto à densidade de tricomas, que incluíram 12 derivados de populações avançadas de retrocruzamentos, obtidos a partir do cruzamento original L. esculentum x L. hirsutum var. glabratum PI 134417. Nas faces abaxial e adaxial dos folíolos, realizaram-se as contagens e os tricomas foram classificados em glandulares tipo IV e VI, outros glandulares (tipo I e VII e não glandulares. A repelência aos ácaros foi medida pela distância média, percorrida pelo

Exploring the Urtica dioica Leaves Hemostatic and Wound-Healing Potential

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Karama Zouari Bouassida

2017-01-01

Full Text Available The present paper investigated the efficiency of Urtica dioica (U. dioica on hemostatic and wound healing activities. U. dioica leaf extracts were evaluated for their antibacterial and antioxidant effects as well as their flavonoid and polyphenol content. The hydroethanolic extract (EtOH-H2OE, showing the most potent antibacterial and antioxidant activities in vitro, thanks to its flavonoid and polyphenol richness, was selected for hemostatic and wound healing evaluation. Twenty-four rats completing full-thickness wounds were split into four groups. The wounds were topically treated with saline solution, glycerol, “CICAFLORA,” and U. dioica EtOH-H2OE (50 µL/mm2 until day 11. The wound healing effect was assessed by macroscopic, histological, and biochemical parameters. Rats treated with EtOH-H2OE showed fast wound closure (92.39% compared to the control animals (60.91% on the 11th day of wounding (P<0.01. Histopathological and biochemical explorations showed full epidermal regeneration and an improvement of the hydroxyproline content in the U. dioica EtOH-H2OE treated rats. Analysis of fatty acids and sterols by GC-MS showed the presence of unsaturated fatty acids and a high concentration of lupeol known for their involvement in reepithelialization. These results prove the efficiency of U. dioica EtOH-H2OE in wound healing and supported its traditional use.

Drought-Stressed Tomato Plants Trigger Bottom-Up Effects on the Invasive Tetranychus evansi.

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Miguel G Ximénez-Embún

Full Text Available Climate change will bring more drought periods that will have an impact on the irrigation practices of some crops like tomato, from standard water regime to deficit irrigation. This will promote changes in plant metabolism and alter their interactions with biotic stressors. We have tested if mild or moderate drought-stressed tomato plants (simulating deficit irrigation have an effect on the biological traits of the invasive tomato red spider mite, Tetranychus evansi. Our data reveal that T evansi caused more leaf damage to drought-stressed tomato plants (≥1.5 fold for both drought scenarios. Mite performance was also enhanced, as revealed by significant increases of eggs laid (≥2 fold at 4 days post infestation (dpi, and of mobile forms (≥2 fold and 1.5 fold for moderate and mild drought, respectively at 10 dpi. The levels of several essential amino acids (histidine, isoleucine, leucine, tyrosine, valine and free sugars in tomato leaves were significantly induced by drought in combination with mites. The non-essential amino acid proline was also strongly induced, stimulating mite feeding and egg laying when added to tomato leaf disks at levels equivalent to that estimated on drought-infested tomato plants at 10 dpi. Tomato plant defense proteins were also affected by drought and/or mite infestation, but T. evansi was capable of circumventing their potential adverse effects. Altogether, our data indicate that significant increases of available free sugars and essential amino acids, jointly with their phagostimulant effect, created a favorable environment for a better T. evansi performance on drought-stressed tomato leaves. Thus, drought-stressed tomato plants, even at mild levels, may be more prone to T evansi outbreaks in a climate change scenario, which might negatively affect tomato production on area-wide scales.

Assessment of Cd-induced genotoxic damage in Urtica pilulifera L. using RAPD-PCR analysis

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Ilhan Dogan

2016-03-01

Full Text Available Plants can be used as biological indicators in assessing the damage done by bioaccumulation of heavy metals and their negative impact on the environment. In the present research, Roman nettle (Urtica pilulifera L. was employed as a bioindicator for cadmium (Cd pollution. The comparisons between unexposed and exposed plant samples revealed inhibition of the root growth (∼25.96% and ∼45.92% after treatment with 100 and 200 µmol/L Cd concentrations, respectively, reduction in the total soluble protein quantities (∼53.92% and ∼66.29% after treatment with 100 and 200 µmol/L Cd concentrations, respectively and a gradual genomic instability when the Cd concentrations were increased. The results indicated that alterations in randomly amplified polymorphic DNA (RAPD profiles, following the Cd treatments, included normal band losses and emergence of new bands, when compared to the controls. Also, the obtained data from F1 plants, utilized for analysis of genotoxicity, revealed that DNA alterations, occurring in parent plants due to Cd pollution, were transmitted to the next generation.

Protective effect of Urtica dioica on liver damage induced by biliary obstruction in rats.

Science.gov (United States)

Oguz, Serhat; Kanter, Mehmet; Erboga, Mustafa; Ibis, Cem

2013-10-01

The aim of this study was to evaluate the possible protective effects of Urtica dioica (UD) against liver damage in the common bile duct-ligated rats. A total of 24 male Sprague Dawley rats were divided into three groups, namely, control, bile duct ligation (BDL) and BDL + received UD groups, containing eight animals in each group. The rats in UD-treated groups were given UD oils (2 ml/kg) once a day intraperitoneally for 2 weeks starting 3 days prior to BDL operation. The change demonstrating the bile duct proliferation and fibrosis in expanded portal tracts includes the extension of proliferated bile ducts into the lobules; inflammatory cell infiltration into the widened portal areas were observed in BDL group. Treatment of BDL with UD attenuated alterations in liver histology. The α-smooth muscle actin, cytokeratin-positive ductular proliferation and the activity of terminal deoxynucleotidyl transferase dUTP nick end labeling in the BDL were observed to be reduced with the UD treatment. The data indicate that UD attenuates BDL-induced cholestatic liver injury, bile duct proliferation and fibrosis.

Geography has a greater effect than Wolbachia infection on population genetic structure in the spider mite, Tetranychus pueraricola.

Science.gov (United States)

Chen, Y-T; Zhang, Y-K; Du, W-X; Jin, P-Y; Hong, X-Y

2016-10-01

Wolbachia is an intracellular symbiotic bacterium that infects various spider mite species and is associated with alterations in host reproduction, which indicates the potential role in mite evolution. However, studies of Wolbachia infections in the spider mite Tetranychus pueraricola, a major agricultural pest, are limited. Here, we used multilocus sequence typing to determine Wolbachia infection status and examined the relationship between Wolbachia infection status and mitochondrial diversity in T. pueraricola from 12 populations in China. The prevalence of Wolbachia ranged from 2.8 to 50%, and three strains (wTpue1, wTpue2, and wTpue3) were identified. We also found double infections (wTpue1 + wTpue3) within the same individuals. Furthermore, the wTpue1 strain caused weak cytoplasmic incompatibility (CI) (egg hatchability ~55%), whereas another widespread strain, wTpue3, did not induce CI. There was no reduction in mitochondrial DNA (mtDNA) or nuclear DNA diversity among infected individuals, and mtDNA haplotypes did not correspond to specific Wolbachia strains. Phylogenetic analysis and analysis of molecular variance revealed that the distribution of mtDNA and nuclear DNA haplotypes were significantly associated with geography. These findings indicate that Wolbachia infection in T. pueraricola is complex, but T. pueraricola genetic differentiation likely resulted from substantial geographic isolation.

Does fragmentation of Urtica habitats affect phytophagous and predatory insects differentially?

Science.gov (United States)

Zabel, Jörg; Tscharntke, Teja

1998-09-01

Effects of habitat fragmentation on the insect community of stinging nettle (Urtica dioica L.) were studied, using 32 natural nettle patches of different area and degree of isolation in an agricultural landscape. Habitat fragmentation reduced the species richness of Heteroptera, Auchenorrhyncha, and Coleoptera, and the abundance of populations. Habitat isolation and area reduction did not affect all insect species equally. Monophagous herbivores had a higher probability of absence from small patches than all (monophagous and polyphagous) herbivore species, and the percentage of monophagous herbivores increased with habitat area. Abundance and population variability of species were negatively correlated and could both be used as a predictor of the percentage of occupied habitats. Species richness of herbivores correlated (positively) with habitat area, while species richness of predators correlated (negatively) with habitat isolation. In logistic regressions, the probability of absence of monophagous herbivores from habitat patches could only be explained by habitat area (in 4 out of 10 species) and predator absence probability only by habitat isolation (in 3 out of 14 species). Presumably because of the instability of higher-trophic-level populations and dispersal limitation, predators were more affected by habitat isolation than herbivores, while they did not differ from herbivore populations with respect to abundance or variability. Thus increasing habitat connectivity in the agricultural landscape should primarily promote predator populations.

Antinociceptive and anti-inflammatory effects of Urtica dioica leaf extract in animal models.

Science.gov (United States)

Hajhashemi, Valiollah; Klooshani, Vahid

2013-01-01

This study was aimed to examine the antinociceptive and anti-inflammatory effects of Urtica dioica leaf extract in animal models. Hydroalcoholic extract of the plant leaves was prepared by percolation method. Male Swiss mice (25-35 g) and male Wistar rats (180-200 g) were randomly distributed in control, standard drug, and three experimental groups (n=6 in each group). Acetic acid-induced writhing, formalin test, and carrageenan-induced paw edema were used to assess the antinociceptive and anti-inflammatory effects. The extract dose-dependently reduced acetic acid-induced abdominal twitches. In formalin test, the extract at any of applied doses (100, 200, and 400 mg/kg) could not suppress the licking behavior of first phase while doses of 200 and 400 mg/kg significantly inhibited the second phase of formalin test. In carrageenan test, the extract at a dose of 400 mg/kg significantly inhibited the paw edema by 26%. The results confirm the folkloric use of the plant extract in painful and inflammatory conditions. Further studies are needed to characterize the active constituents and the mechanism of action of the plant extract.

Effects of urtica dioica extract on experimental acute pancreatitis model in rats.

Science.gov (United States)

Yilmaz, Baris; Basar, Omer; Aktas, Bora; Altinbas, Akif; Ekiz, Fuat; Büyükcam, Fatih; Albayrak, Aynur; Ginis, Zeynep; Oztürk, Gülfer; Coban, Sahin; Ucar, Engin; Kaya, Oskay; Yüksel, Osman; Caner, Sedat; Delibasi, Tuncay

2014-01-01

Acute pancreatitis is the acute inflammation of pancreas and peripancreatic tissues, and distant organs are also affected. The aim of this study was to investigate the effect of Urtica dioica extract (UDE) treatment on cerulein induced acute pancreatitis in rats. Twenty-one Wistar Albino rats were divided into three groups: Control, Pancreatitis, and UDE treatment group. In the control group no procedures were performed. In the pancreatitis and treatment groups, pancreatitis was induced with intraperitoneal injection of cerulein, followed by intraperitoneal injection of 1 ml saline (pancreatitis group) and 1 ml 5.2% UDE (treatment group). Pancreatic tissues were examined histopathologically. Pro-inflammatory cytokines (tumor necrosis factor-α), amylase and markers of apoptosis (M30, M65) were also measured in blood samples. Immunohistochemical staining was performed with Caspase-3 antibody. Histopathological findings in the UDE treatment group were less severe than in the pancreatitis group (5.7 vs 11.7, p = 0.010). TNF-α levels were not statistically different between treated and control groups (63.3 vs. 57.2, p = 0.141). UDE treatment was associated with less apoptosis [determined by M30, caspase-3 index (%)], (1.769 vs. 0.288, p = 0.056; 3% vs. 2.2%, p = 0.224; respectively). UDE treatment of pancreatitis merits further study.

Evaluación de la distribución poblacional del Acaro Tetranychus cinnabarinus (Boisduval en clavel (Dianthus caryophyllus L.

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Luna Segura Diego Marino

1987-12-01

Full Text Available Some important ecological topics about Tetranychus cinnabarinus (Boisduval. (Acari: Tetranychidae pest management was studied in a comercial crop of carnation Dianthus caryophyllus L. in greenhouse in Suba - Cundinamarca. Population of mites was evaluated on 3 thirds and 9 ages of plants during rainy and dry season. 34.8334.61% were found on the up third and 27.84% were found on the lower third of plants. Mite population reached equilibrium state, de life cycle was 37.19C% for egg;
20.50% for larva; 24.37% ninfal stages and 17.54% for adults. Trifolium repens L.; Stellaris media (L. Cyrill; Pos annua L.; Veronica persica Poir; Holcus lanatus L. and
Oxslis corniculata L. were found as secondary hosts for T. cinneberinus during this studv, In laboratory conditions, 300C and 85 ± 5% R.H., the life cycle of Tetrsnychuscinnabarinus
(Boisduval. on Triototium repens L. Was shorter than the life cycle on carnation (Disnthus csryopbvtlu. L..El trabajo se desarrolló bajo condiciones de cultivo comercial (Municipio de Suba, Cundinamarca, abordó interrogantes
de interés específico para el manejo de ácaros en clavel, como son principalmente: dinámica de población y efecto
del ciclo de vida. Bajo invernadero, se evaluó la distribución vertical de poblaciones teniendo en cuenta: tres estratos, nueve edades de planta y dos épocas (lluviosa y seca; además se buscaron hospedantes secundarios del ácaro. Las mayores poblaciones de arañita se presentaron en plantas de 19, 20 y 21 meses de edad, con un 34.83% del total. Al tener en cuenta distribución vertical se observó que el estrato medio contiene la mayor población, el 37.55% y la menor, el
estrato inferior con el 27.84%. Al comparar los diferentes estados del ciclo de vida del ácaro se pudo ver la condición de equilibrio estable de su poblaci

Effects of powdery mildew fungicide programs on twospotted spider mite (Acari: Tetranychidae), hop aphid (Hemiptera: Aphididae), and their natural enemies in hop yards.

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Gent, D H; James, D G; Wright, L C; Brooks, D J; Barbour, J D; Dreves, A J; Fisher, G C; Walton, V M

2009-02-01

Twospotted spider mite, Tetranychus urticae Koch (Acari: Tetranychidae), and hop aphid, Phorodon humuli (Schrank) (Hemiptera: Aphididae), are the most important arthropod pests of hop (Humulus lupulus L.) in the Northern Hemisphere. A potential barrier for greater adoption of conservation biological control strategies for spider mites and hop aphid is the extensive use of fungicides for management of hop powdery mildew, Podosphaera macularis (Wallr.:Fr.) U. Braun & S. Takamatsu. Field studies conducted in experimental plots in Oregon and Washington in 2005 and 2006 quantified the effects of powdery mildew fungicide programs (i.e., sulfur, paraffinic oil, and synthetic fungicides) on arthropod pests and natural enemies on hop. Fungicide treatment significantly affected spider mite populations in all four studies. Multiple applications of sulfur fungicides applied before burr development resulted in 1.4-3.3-fold greater spider mite populations during summer. Near the cessation of the sulfur applications, or after a lag of 20-30 d, spider mite populations increased significantly faster on sulfur treated plants compared with water-treated plants in three of four experiments. The effect of paraffinic oil on spider mites was varied, leading to exacerbation of spider mites in Oregon and Washington in 2005, suppression of mites in Oregon in 2006, and no significant effect compared with water in Washington in 2006. Significant relative treatment effects for cone damage due to spider mite feeding were detected in Oregon in 2005 in plots treated with sulfur and paraffinic oil compared with water and synthetic fungicides. Mean populations of hop aphids were similar among treatments in Oregon, although sulfur treatment suppressed hop aphid populations in Washington in 2005 and 2006. Populations of individual predacious insect species and cumulative abundance of macropredators were not consistently suppressed or stimulated by treatments in all trials. However, predatory mite

Stinging Nettle (Urtica dioica L. Attenuates FFA Induced Ceramide Accumulation in 3T3-L1 Adipocytes in an Adiponectin Dependent Manner.

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Diana N Obanda

Full Text Available Excess dietary lipids result in the accumulation of lipid metabolites including ceramides that can attenuate insulin signaling. There is evidence that a botanical extract of Urtica dioica L. (stinging nettle improves insulin action, yet the precise mechanism(s are not known. Hence, we examined the effects of Urtica dioica L. (UT on adipocytes.We investigated the effects of an ethanolic extract of UT on free fatty acid (palmitic acid induced inhibition of insulin-stimulated Akt serine phosphorylation and modulation of ceramidase expression in 3T3-L1 adipocytes. Adipocytes were exposed to excess FFAs in the presence or absence of UT. Effects on adiponectin expression, ceramidase expression, ceramidase activity, ceramide accumulation and insulin signaling were determined.As expected, FFAs reduced adiponectin expression and increased the expression of ceramidase enzymes but not their activity. FFA also induced the accumulation of ceramides and reduced insulin-stimulated phosphorylation of Akt in adipocytes. The effects of FFA were partially reversed by UT. UT enhanced adiponectin expression and ceramidase activity in the presence of excess FFAs. UT abated ceramide accumulation and increased insulin sensitivity via enhanced Akt phosphorylation. A siRNA knockdown of adiponectin expression prevented UT from exerting positive effects on ceramidase activity but not Akt phosphorylation.In adipocytes, the ability of UT to antagonize the negative effects of FFA by modulating ceramidase activity and ceramide accumulation is dependent on the presence of adiponectin. However, the ability of UT to enhance Akt phosphorylation is independent of adiponectin expression. These studies demonstrate direct effects of UT on adipocytes and suggest this botanical extract is metabolically beneficial.

Modeling the accumulation of As, Cd, Cu, Pb and Zn in grasses (Agrotis sp. and Poa sp. and stinging nettle (Urtica dioica on selected sites taking into account soil physico-chemical properties

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Boshoff M.C.

2014-07-01

Full Text Available The effect of soil properties on the accumulation of metals in two vegetation types was evaluated at 10 sites with a wide variation in soil physicochemical properties pH, organic carbon, clay percentage , total soil metal concentration and exchangeable soil metal content. Accumulation modeling was conducted for grasses (Agrostis sp. and Poa sp. and stinging nettle (Urtica dioica.

Modeling the accumulation of As, Cd, Cu, Pb and Zn in grasses (Agrotis sp. and Poa sp. and stinging nettle (Urtica dioica on selected sites taking into account soil physico-chemical properties

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Boshoff M. C.

2013-04-01

Full Text Available The effect of soil properties on the accumulation of metals in two vegetation types was evaluated at 10 sites with a wide variation in soil physicochemical properties pH, organic carbon, clay percentage , total soil metal concentration and exchangeable soil metal content. Accumulation modeling was conducted for grasses (Agrostis sp. and Poa sp. and stinging nettle (Urtica dioica.

A study on possible use of Urtica dioica (common nettle) plants as uranium (234U, 238U) contamination bioindicator near phosphogypsum stockpile.

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Olszewski, Grzegorz; Boryło, Alicja; Skwarzec, Bogdan

The aim of this study was to determine uranium concentrations in common nettle ( Urtica dioica ) plants and corresponding soils samples which were collected from the area of phosphogypsum stockpile in Wiślinka (northern Poland). The uranium concentrations in roots depended on its concentrations in soils. Calculated BCF and TF values showed that soils characteristics and air deposition affect uranium absorption and that different uranium species have different affinities to U . dioica plants. The values of 234 U/ 238 U activity ratio indicate natural origin of these radioisotopes in analyzed plants. Uranium concentration in plants roots is negatively weakly correlated with distance from phosphogypsum stockpile.

A study on possible use of Urtica dioica (common nettle) plants as uranium (234U, 238U) contamination bioindicator near phosphogypsum stockpile

International Nuclear Information System (INIS)

Olszewski, Grzegorz; Borylo, Alicja; Skwarzec, Bogdan

2016-01-01

The aim of this study was to determine uranium concentrations in common nettle (Urtica dioica) plants and corresponding soils samples which were collected from the area of phosphogypsum stockpile in Wislinka (northern Poland). The uranium concentrations in roots depended on its concentrations in soils. Calculated BCF and TF values showed that soils characteristics and air deposition affect uranium absorption and that different uranium species have different affinities to U. dioica plants. The values of 234 U/ 238 U activity ratio indicate natural origin of these radioisotopes in analyzed plants. Uranium concentration in plants roots is negatively weakly correlated with distance from phosphogypsum stockpile. (author)

Pecan (Carya illinoinensis/Wangenh./K. Koch: A new species of the Allochthonous dendroflora in Serbia

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Bobinac Martin

2014-01-01

Full Text Available This paper presents the alien species Carya illinoinensis (Wangenh. K. Koch, carya-pecan, (Juglandaceae A. Richard ex Kunth that has not been mentioned so far in the dendroflora of Serbia. One tree was recorded within the first Serbian sugar factory in Čukarica that is now a protected cultural property in the City of Belgrade. The tree is about 35 years old and about 20 m high. The length of the trunk without branches is 6.0 m and the diameter at breast height is 57 cm. Carya-pecan is a native species of the southeastern part of North America, and is grown in Europe for edible fruits and quality wood. The recorded tree in Belgrade is fruitful and characterized by good vitality and rapid growth. Due to its special characteristics, it can have multiple practical application in the territory of Serbia for decoration in urban areas, for forest plantations and in orchards. [Projekat Ministarstva nauke Republike Srbije, br. 31041: Šumski zasadi u funkciji povećanja pošumljenosti Srbije

A scanning proton microprobe study of stinging emergences from the leaf of the common stinging nettle urtica dioica l.

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Hughes, N. P.; Perry, C. C.; Williams, R. J. P.; Watt, F.; Grime, G. W.

1988-03-01

Proton-induced X-ray emission (PIXE) combined with the Oxford scanning proton microprobe (SPM) was used to investigate the abundance and spatial distribution of inorganic elements in mineralising stinging emergences from the leaf of the Common Stinging Nettle, Urtica dioica L. Elemental maps and point analytical data were collected for emergences at two stages of maturity. In all emergences calcium and silicon were spatially organised and present at high concentration. The inorganic elements K, P, S and Mn were also spatially organised during mineralisation, but at maturity these elements were present only at background levels and then showed no specific localisation. The observed changes in the inorganic content of the emergences are obviously related to the mineralisation processes. The possible biochemical significance of the distribution of the elements is discussed.

Comparison of nutritional properties of Stinging nettle (Urtica dioica) flour with wheat and barley flours.

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Adhikari, Bhaskar Mani; Bajracharya, Alina; Shrestha, Ashok K

2016-01-01

Stinging nettle (Urtica dioica. L) is a wild, unique herbaceous perennial flowering plant with Stinging hairs. It has a long history of use as a food sources as a soup or curries, and also used as a fiber as well as a medicinal herb. The current aim was to analyze the composition and bioactive compounds in Nepalese Stinging nettle. Chemical analysis showed the relatively higher level of crude protein (33.8%), crude fiber (9.1%), crude fat (3.6%), total ash (16.2%), carbohydrate (37.4%), and relatively lower energy value (307 kcal/100 g) as compared to wheat and barley flours. Analysis of nettle powder showed significantly higher level of bioactive compounds: phenolic compounds as 129 mg Gallic acid equivalent/g; carotenoid level 3497 μg/g; tannin 0.93 mg/100 g; anti-oxidant activity 66.3 DPPH inhibition (%), as compared to wheat and barley. This study further established that nettle plants as very good source of energy, proteins, high fiber, and a range of health benefitting bioactive compounds.

Mechanisms underlying the antihypertensive properties of Urtica dioica.

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Qayyum, Rahila; Qamar, Hafiz Misbah-Ud-Din; Khan, Shamim; Salma, Umme; Khan, Taous; Shah, Abdul Jabbar

2016-09-01

Urtica dioica has traditionally been used in the management of cardiovascular disorders especially hypertension. The aim of this study was to explore pharmacological base of its use in hypertension. Crude methanolic extract of U. dioica (Ud.Cr) and its fractions (Ud.EtAc, Ud.nHex, Ud.Chl and Ud.Aq) were tested in vivo on normotensive and hypertensive rats under anesthesia for blood pressure lowering effect. In-vitro experiments on rat and rabbit aortae were employed to probe the vasorelaxation mechanism(s). The responses were measured using pressure and force transducers connected to PowerLab Data Acquisition System. Ud.Cr and fractions were found more effective antihypertensive in hypertensive rats than normotensive with remarkable potency exhibited by the ethyl acetate fraction. The effect was same in the presence of atropine. In isolated rat aortic rings, Ud.Cr and all its fractions exhibited L-NAME sensitive endothelium-dependent vasodilator effect and also inhibit K(+) (80 mM)-induced pre-contractions. In isolated rabbit thoracic aortic rings Ud.Cr and its fractions induced relaxation with more potency against K(+) (80 mM) than phenylephrine (1 µM) like verapamil, showing Ud.EtAc fraction the most potent one. Pre-incubation of aortic rings with Ud.Cr and its fractions exhibited Ca(2+) channel blocking activity comparable with verapamil by shifting Ca(2+) concentration response curves to the right. Ud.Cr and its fractions also ablated the intracellular Ca(2+) release by suppressing PE peak formation in Ca(2+) free medium. When tested on basal tension, the crude extract and all fractions were devoid of any vasoconstrictor effect. These data indicate that crude methanolic extract and its fractions possess antihypertensive effect. Identification of NO-mediated vasorelaxation and calcium channel blocking effects explain the antihypertensive potential of U. dioica and provide a potential pharmacological base to its medicinal use in the management of hypertension.

Selection of entomopathogenic fungi against the red spider mite Tetranychus kanzawai (Kishida (Tetranychidae: Acarina

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Yayan Sanjaya

2013-12-01

Full Text Available The pathogenicity of three entomopathogenic fungal species to Tetranychus kanzawai was investigated. Seven isolates of Metarhizium anisopliae, six isolates of Beauveria bassiana, and an isolate of Paecilomyces lilacinus from the Philippines and Indonesia were evaluated. The following studies were undertaken: (1 screening of M. anisoplae, B. bassiana and P. lilicanus pathogenic to T. kanzawai, and (2 bioefficacy studies of the selected entomopathogenic fungi under greenhouse conditions. Conidia of each isolate were mass-produced on potato dextrose agar (PDA at 26+-1 oC and a 12-hour photophase for a maximum of 21 days. Preliminary screening for the most pathogenic isolate within the same species was determined using suspension with 104 to 108 conidia ml-1. At 4 days after treatment (DAT, the pathogenicity within M. anisopliae isolates in decreasing order was Ma5>Ma6>Ma4>Ma2>Ma1>Ma3>Ma7 while for B. bassiana, was Bb6>Bb5>Bb4>Bb3>Bb1>Bb2. The top three most pathogenic isolates within the two species were subjected to further studies to determine the most virulent isolate against T. kanzawai. At 5 DAT, the LC50 values of M. anisopliae isolates ranged from 5.0 x102 to 1.4x103 while for B. bassiana ranged from 1.2 x 103 to 2.4x 103 conidia ml-1. Based on LC50, the virulence of the fungal isolates within the species in decreasing order was Ma6>Ma5>Ma4 and Bb6>Bb5>Bb4. However, the LC50 values are not significantly different from each other. Green house trials showed that the epizootic of entomopathogenic fungus can regulate the population of mites. The fungal isolates used in the study, although not originally isolated from mites were virulent to T. kanzawai, indicating their wide host range.

Ex-vivo in-vitro inhibition of lipopolysaccharide stimulated tumor necrosis factor-alpha and interleukin-1 beta secretion in human whole blood by extractum urticae dioicae foliorum.

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Obertreis, B; Ruttkowski, T; Teucher, T; Behnke, B; Schmitz, H

1996-04-01

An extract of Urtica dioica folium (IDS 23, Rheuma-Hek), monographed positively for adjuvant therapy of rheumatic diseases and with known effects in partial inhibition of prostaglandin and leukotriene synthesis in vitro, was investigated with respect to effects of the extract on the lipopolysaccharide (LPS) stimulated secretion of proinflammatory cytokines in human whole blood of healthy volunteers. In the assay system used, LPS stimulated human whole blood showed a straight increase of tumor necrosis factor-alpha (TNF-alpha) and interleukin-1 beta (IL-1 beta) secretion reaching maximum concentrations within 24 h following a plateau and slight decrease up to 65 h, respectively. The concentrations of these cytokines was strongly positively correlated with the number of monocytes/macrophages of each volunteer. TNF-alpha and IL-1 beta concentration after LPS stimulation was significantly reduced by simultaneously given IDS 23 in a strictly dose dependent manner. At time 24 h these cytokine concentrations were reduced by 50.8% and 99.7%, respectively, using the highest test IDS 23 assay concentration of 5 mg/ml (p flavonoides such as caffeic malic acid, caffeic acid, chlorogenic acid, quercetin and rutin did not influence LPS stimulated TNF-alpha, IL-1 beta and IL-6 secretion in tested concentrations up to 5 x 10(-5) mol/l. These further findings on the pharmacological mechanism of action of Urticae dioica folia may explain the positive effects of this extract in the treatment of rheumatic diseases.

State-dependent and odour-mediated anemotactic responses of the predatory mite Phytoseiulus persimilis in a wind tunnel.

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Van Tilborg, Merijn; Sabelis, Maurice W; Roessingh, Peter

2004-01-01

Anemotaxis in the predatory mite Phytoseiulus persimilis (both well-fed and starved), has previously been studied on a wire grid under slight turbulent airflow conditions yielding weak, yet distinct, gradients in wind speed and odour concentration (Sabelis and Van der Weel 1993). Such conditions might have critically influenced the outcome of the study. We repeated these experiments, under laminar airflow conditions on a flat surface in a wind tunnel, thereby avoiding variation in wind speed and odour concentration. Treatments for starved and well-fed mites were (1) still-air without herbivore-induced plant volatiles (HIPV) (well-fed mites only), (2) an HIPV-free air stream, and (3) an air stream with HIPV (originating from Lima bean plants infested by two-spotted spider mites, Tetranychus urticae). Well-fed mites oriented in random directions in still-air without HIPV. In an air stream, starved mites always oriented upwind, whether plant odours were present or not. Well-fed mites oriented downwind in an HIPV-free air stream, but in random directions in an air stream with HIPV. Only under the last treatment our results differed from those of Sabelis and Van der Weel (1993).

Differential Timing of Spider Mite-Induced Direct and Indirect Defenses in Tomato Plants1[w

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Kant, Merijn R.; Ament, Kai; Sabelis, Maurice W.; Haring, Michel A.; Schuurink, Robert C.

2004-01-01

Through a combined metabolomics and transcriptomics approach we analyzed the events that took place during the first 5 d of infesting intact tomato (Lycopersicon esculentum) plants with spider mites (Tetranychus urticae). Although the spider mites had caused little visible damage to the leaves after 1 d, they had already induced direct defense responses. For example, proteinase inhibitor activity had doubled and the transcription of genes involved in jasmonate-, salicylate-, and ethylene-regulated defenses had been activated. On day four, proteinase inhibitor activity and particularly transcript levels of salicylate-regulated genes were still maintained. In addition, genes involved in phospholipid metabolism were up-regulated on day one and those in the secondary metabolism on day four. Although transcriptional up-regulation of the enzymes involved in the biosynthesis of monoterpenes and diterpenes already occurred on day one, a significant increase in the emission of volatile terpenoids was delayed until day four. This increase in volatile production coincided with the increased olfactory preference of predatory mites (Phytoseiulus persimilis) for infested plants. Our results indicate that tomato activates its indirect defenses (volatile production) to complement the direct defense response against spider mites. PMID:15122016

When do predatory mites (Phytoseiidae) attack? Understanding their diel and seasonal predation patterns.

Science.gov (United States)

Pérez-Sayas, Consuelo; Aguilar-Fenollosa, Ernestina; Hurtado, Mónica A; Jaques, Josep A; Pina, Tatiana

2017-06-16

Predatory mites of the Phytoseiidae family are considered one of the most important groups of natural enemies used in biological control. The behavioral patterns of arthropods can differ greatly daily and seasonally; however, there is a lack of literature related to Phytoseiidae diel and seasonal predation patterns. The predatory activity of three phytoseiid species (two Tetranychidae-specialists, Phytoseiulus persimilis and Neoseiulus californicus, and one omnivore, Euseius stipulatus) that occur naturally in Spanish citrus orchards was observed under laboratory conditions in winter and summer. The temperature and photoperiod of the climatic chamber where the mites were reared did not change during the experiment. Our study demonstrates that phytoseiids can exhibit diel and seasonal predatory patterns when feeding on Tetranychus urticae (Acari: Tetranychidae). Neoseiulus californicus was revealed to be a nocturnal predator in summer but diurnal in winter. In contrast, P. persimilis activity was maximal during the daytime, and E. stipulatus showed no clear daily predation patterns. The predatory patterns described in this study should be taken into account when designing laboratory studies and also in field samplings, especially when applying molecular techniques to unveil trophic relationships. © 2017 Institute of Zoology, Chinese Academy of Sciences.

Possibility in application of electron beam irradiation to plant quarantine of cut flowers

International Nuclear Information System (INIS)

Tanabe, Kazuo

1994-01-01

For the purpose of developing new quarantine procedure alternative to fumigation, electron beam irradiation was examined in the disinfestation of arthroped pests that infest cut flowers. Immature and adult two-spotted spider mites, Tetranychus urticae, which is a typical pest in horticulture due to high fertility, parthenogenesis and chemical resistance, were irradiated at a Van de graaf electron accelerator (2.5 MeV) at 0.2 - 1.4 kGy. They decreased radiosensitivity with aging. Female was much more tolerant than male throughout their life. Irradiation controlled the fertility of both sexes, and also feeding and behavioral activities. Cut flowers irradiated with the Dynamitron accelerator (5 MeV) showed various responses according to species, cultivars and tissues of plants. Carnations, tulips and gladioluses were tolerant in disinfesting or sterilizing, but some cultivars of chrysanthemum and rose showed the symptom of injury, in which flowering was delayed at low dose, and the failure of flowering and the chlorosis of leaves occurred at high dose. Floral organs were much more sensitive to radiation than others. Sensitive plants also showed the reduced production of ethylene. (K.I.)

Ameliorative effects of stinging nettle (Urtica dioica) on testosterone-induced prostatic hyperplasia in rats.

Science.gov (United States)

Nahata, A; Dixit, V K

2012-05-01

The present study investigated the effects of stinging nettle (Urtica dioica L.) (UD) on benign prostatic hyperplasia (BPH) induced by testosterone. In vitro studies were conducted to assess the 5α-reductase inhibitory potential of UD. Two biochemical markers viz., β-sitosterol and scopoletin, were isolated and characterised in the extracts utilising High-performance thin layer chromatographic, FTIR, NMR and overlain UV spectral studies. Hyperplasia was induced in rats by subcutaneous administration of testosterone (3 mg kg(-1) s.c.) for 28 days in all the groups except the vehicle-treated group. Simultaneous administration of petroleum ether and ethanolic extracts (10, 20 and 50 mg kg(-1) p.o.) and isolated β-sitosterol (10 and 20 mg kg(-1) p.o.) was undertaken. Finasteride was used as a positive control (1 mg kg(-1) p.o.). Measurement of prostate/body weight ratio, weekly urine output and serum testosterone levels, prostate-specific antigen levels (on day 28) and histological examinations carried out on prostates from each group led us to conclude that UD can be used as an effective drug for the management of BPH. © 2011 Blackwell Verlag GmbH.

Biologia e tabela de vida do ácaro-vermelho Tetranychus bastosi em pinhão-manso

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Marçal Pedro Neto

2013-04-01

Full Text Available O objetivo deste trabalho foi determinar a biologia e a tabela de vida de Tetranychus bastosi em pinhão-manso (Jatropha curcas. O experimento foi realizado em ambiente controlado a 26ºC e 75% de UR, com fotófase de 12 horas. Os ovos usados nos experimentos foram oriundos de criação estoque. As avaliações foram realizadas duas vezes ao dia, para a biologia do ácaro, e uma vez, para os parâmetros reprodutivos. O ciclo médio de vida das fêmeas foi de 9,63 dias e o dos machos, de 8,94 dias. A razão sexual foi 0,65 e a longevidade média das fêmeas foi de 16 dias, com produção média de 59 ovos por fêmea. Os parâmetros de tabela de vida obtidos foram: taxa líquida de reprodução (Ro, 45,41 indivíduos; duração média das gerações (T, 12,66 dias; taxa intrínseca de crescimento (r m, 0,0538 fêmea por fêmea por dia; razão finita de aumento (λ, 1,023 fêmea por fêmea; e tempo para duplicação da população (TD, 3,15 dias. O ácaro T. bastosi desenvolve-se bem e apresenta alto potencial reprodutivo sobre folhas de pinhão-manso.

Effect of acaricidal components isolated from lettuce (Lactuca sativa) on carmine spider mite (Tetranychus cinnabarinus Boisd.).

Science.gov (United States)

Li, M; Zhang, Y; Ding, W; Luo, J; Li, S; Zhang, Q

2018-06-01

This study aimed to evaluate the acaricidal activity of lettuce (Lactuca sativa) extracts against carmine spider mites (Tetranychus cinnabarinus Boisd.) and isolate the acaricidal components. Acaricidal activities of lettuce extracts isolated from different parts (the leaf, root and seed) using various solvents (petroleum ether, acetone and methanol) were evaluated with slide-dip bioassay and relatively high median lethal concentration (LC50) values were detected. Acetone extracts of lettuce leaves harvested in July and September were fractionated and isolated with silica gel and thin-layer chromatography. Consequently, acetone extracts of lettuce leaves harvested in July exhibited higher acaricidal activity than those harvested in September, with an LC50 value of 0.268 mg ml-1 at 72 h post-treatment. A total of 27 fractions were obtained from the acetone extract of lettuce leaves harvested in July, and mite mortalities with the 11th and 12th fractions were higher than those with the other 25 fractions (LC50: 0.751 and 1.258 mg ml-1 at 48 h post-treatment, respectively). Subsequently, active acaricidal components of the 11th fraction were identified by infrared, nuclear magnetic resonance and liquid chromatography/mass spectrometry. Five components were isolated from the 11th fraction, with components 11-a and 11-b showing relatively high acaricidal activities (LC50: 0.288 and 0.114 mg ml-1 at 48 h post-treatment, respectively). Component 11-a was identified as β-sitosterol. In conclusion, acetone extracts of lettuce leaves harvested in July might be used as a novel phytogenic acaricide to control mites.

Chitosan films incorporated with nettle (Urtica dioica L.) extract-loaded nanoliposomes: I. Physicochemical characterisation and antimicrobial properties.

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Haghju, Sara; Beigzadeh, Sara; Almasi, Hadi; Hamishehkar, Hamed

2016-07-17

The objective of this study was to characterise and compare physical, mechanical and antimicrobial properties of chitosan-based films, containing free or nanoencapsulated nettle (Urtica dioica L.) extract (NE) at concentrations of 0, 0.5, 1 and 1.5% w/w. Nanoliposomes were prepared using soy-lecithin by thin-film hydration and sonication method to generate an average size of 107-136 nm with 70% encapsulation efficiency. The information on FT-IR reflected that some new interaction have occurred between chitosan and nanoliposomes. Despite the increasing yellowness and decreasing whiteness indexes, the nanoliposomes incorporation improved the thermal properties and mechanical stiffness and caused to decrease water vapour permeability (WVP), moisture uptake and water solubility. The possible antimicrobial activity of the films containing NE-loaded nanoliposomes against Staphylococcus aureus was decreased in comparison to free NE-incorporated films, which could be due to the inhibition effect of the encapsulation that prevents the release of NE from the matrix.

Microscopical, macroscopical and chemical investigations and their uses in chemotaxonomy of Crataegus pontica C. Koch

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Nasrollah Ghassemi Dehkordi

2012-06-01

Full Text Available The Crataegus genus is widely distributed in Iran. This genus belongs to Rosaceae family and has 17 species in Iran one of which is Crataegus pontica C. Koch. In this paper, we analyzed some microscopic and macroscopic characteristics of this plant, then compared them with other features that were presented previously in previous reports. We analyzed all components in C. pontica, using thin layer chromatography method and then specified the type of flavonoids and hydroxycinnamic acid in C. pontica. Hyproside, rutin and chlorogenic acid were the main flavonoids and hydroxycinnamic occurred acid in this plant. Also, we analyzed its flavonoids quantitatively based on Deutsch Pharmacopoeia method according to hyproside content. Because, to determine the chemosystematic relevancies in some species flavonoids are used, so in this paper we compared C. pontica with 3 other species of its genus such as C. monogyna, C. melanocarpa and C. curvisepala that are found in Iran, and also with the medicinal standard species of Crataegus genus which is called C. oxyacantha. Finally we concluded that hyproside, rutin and chlorogenic acid were the main and common structural components in all species of that genus which were mentioned above.

Transcriptome Analysis of the Carmine Spider Mite, Tetranychus cinnabarinus (Boisduval, 1867 (Acari: Tetranychidae, and Its Response to β-Sitosterol

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Chunya Bu

2015-01-01

Full Text Available Tetranychus cinnabarinus (Acari: Tetranychidae is a worldwide polyphagous agricultural pest that has the title of resistance champion among arthropods. We reported previously the identification of the acaricidal compound β-sitosterol from Mentha piperita and Inula japonica. However, the acaricidal mechanism of β-sitosterol is unclear. Due to the limited genetic research carried out, we de novo assembled the transcriptome of T. cinnabarinus using Illumina sequencing and conducted a differential expression analysis of control and β-sitosterol-treated mites. In total, we obtained >5.4 G high-quality bases for each sample with unprecedented sequencing depth and assembled them into 22,941 unigenes. We identified 617 xenobiotic metabolism-related genes involved in detoxification, binding, and transporting of xenobiotics. A highly expanded xenobiotic metabolic system was found in mites. T. cinnabarinus detoxification genes—including carboxyl/cholinesterase and ABC transporter class C—were upregulated after β-sitosterol treatment. Defense-related proteins, such as Toll-like receptor, legumain, and serine proteases, were also activated. Furthermore, other important genes—such as the chloride channel protein, cytochrome b, carboxypeptidase, peritrophic membrane chitin binding protein, and calphostin—may also play important roles in mites’ response to β-sitosterol. Our results demonstrate that high-throughput-omics tool facilitates identification of xenobiotic metabolism-related genes and illustration of the acaricidal mechanisms of β-sitosterol.

Urtica dioica modulates hippocampal insulin signaling and recognition memory deficit in streptozotocin induced diabetic mice.

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Patel, Sita Sharan; Gupta, Sahil; Udayabanu, Malairaman

2016-06-01

Diabetes mellitus has been associated with functional abnormalities in the hippocampus and performance of cognitive function. Urtica dioica (UD) has been used in the treatment of diabetes. In our previous report we observed that UD extract attenuate diabetes mediated associative and spatial memory dysfunction. The present study aimed to evaluate the effect of UD extract on mouse model of diabetes-induced recognition memory deficit and explore the possible mechanism behind it. Streptozotocin (STZ) (50 mg/kg, i.p. consecutively for 5 days) was used to induce diabetes followed by UD extract (50 mg/kg, oral) or rosiglitazone (ROSI) (5 mg/kg, oral) administration for 8 weeks. STZ induced diabetic mice showed significant decrease in hippocampal insulin signaling and translocation of glucose transporter type 4 (GLUT4) to neuronal membrane resulting in cognitive dysfunction and hypolocomotion. UD treatment effectively improved hippocampal insulin signaling, glucose tolerance and recognition memory performance in diabetic mice, which was comparable to ROSI. Further, diabetes mediated oxidative stress and inflammation was reversed by chronic UD or ROSI administration. UD leaves extract acts via insulin signaling pathway and might prove to be effective for the diabetes mediated central nervous system complications.

Amistades Internacionales como contribución a la paz. La correspondencia entre Paul Rivet y Theodor Koch - Grünberg en el contexto de la Primera Guerra Mundial.

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Michael Kraus.

2010-07-01

Full Text Available This article analyzes the correspondence between the French anthropologist paul rivet (1876-1958, and the german anthropologist theodor Koch-grünberg (1872-1924 after the First World War. the letters illustrate how both anthropologists struggled to reactivate the scientifc exchange between the two nations which had been interrupted by the war. their interest in common research themes, which had always transcended their national borders, established a collaborative attempt to overcome hostility and further appreciate international discourses over national ideologies.

Influence of Heavy Metal Stress on Antioxidant Status and DNA Damage in Urtica dioica

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Darinka Gjorgieva

2013-01-01

Full Text Available Heavy metals have the potential to interact and induce several stress responses in the plants; thus, effects of heavy metal stress on DNA damages and total antioxidants level in Urtica dioica leaves and stems were investigated. The samples are sampled from areas with different metal exposition. Metal content was analyzed by Inductively Coupled Plasma-Atomic Emission Spectrometer (ICP-AES, for total antioxidants level assessment the Ferric-Reducing Antioxidant Power (FRAP assay was used, and genomic DNA isolation from frozen plant samples was performed to obtain DNA fingerprints of investigated plant. It was found that heavy metal contents in stems generally changed synchronously with those in leaves of the plant, and extraneous metals led to imbalance of mineral nutrient elements. DNA damages were investigated by Random Amplified Polymorphic DNA (RAPD technique, and the results demonstrated that the samples exposed to metals yielded a large number of new fragments (total 12 in comparison with the control sample. This study showed that DNA stability is highly affected by metal pollution which was identified by RAPD markers. Results suggested that heavy metal stress influences antioxidant status and also induces DNA damages in U. dioica which may help to understand the mechanisms of metals genotoxicity.

Influence of heavy metal stress on antioxidant status and DNA damage in Urtica dioica.

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Gjorgieva, Darinka; Kadifkova Panovska, Tatjana; Ruskovska, Tatjana; Bačeva, Katerina; Stafilov, Trajče

2013-01-01

Heavy metals have the potential to interact and induce several stress responses in the plants; thus, effects of heavy metal stress on DNA damages and total antioxidants level in Urtica dioica leaves and stems were investigated. The samples are sampled from areas with different metal exposition. Metal content was analyzed by Inductively Coupled Plasma-Atomic Emission Spectrometer (ICP-AES), for total antioxidants level assessment the Ferric-Reducing Antioxidant Power (FRAP) assay was used, and genomic DNA isolation from frozen plant samples was performed to obtain DNA fingerprints of investigated plant. It was found that heavy metal contents in stems generally changed synchronously with those in leaves of the plant, and extraneous metals led to imbalance of mineral nutrient elements. DNA damages were investigated by Random Amplified Polymorphic DNA (RAPD) technique, and the results demonstrated that the samples exposed to metals yielded a large number of new fragments (total 12) in comparison with the control sample. This study showed that DNA stability is highly affected by metal pollution which was identified by RAPD markers. Results suggested that heavy metal stress influences antioxidant status and also induces DNA damages in U. dioica which may help to understand the mechanisms of metals genotoxicity.

Mineral Properties and Dietary Value of Raw and Processed Stinging Nettle (Urtica dioica L.)

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Xu, Yixiang; Ramirez, Elizabeth

2013-01-01

Stinging nettle (Urtica dioica L.) has a long history of usage and is currently receiving attention as a source of fiber and alternative medicine. In many cultures, nettle is also eaten as a leafy vegetable. In this study, we focused on nettle yield (edible portion) and processing effects on nutritive and dietary properties. Actively growing shoots were harvested from field plots and leaves separated from stems. Leaf portions (200 g) were washed and processed by blanching (1 min at 96–98°C) or cooking (7 min at 98-99°C) with or without salt (5 g·L−1). Samples were cooled immediately after cooking and kept in frozen storage before analysis. Proximate composition, mineral, amino acid, and vitamin contents were determined, and nutritive value was estimated based on 100 g serving portions in a 2000 calorie diet. Results show that processed nettle can supply 90%–100% of vitamin A (including vitamin A as β-carotene) and is a good source of dietary calcium, iron, and protein. We recommend fresh or processed nettle as a high-protein, low-calorie source of essential nutrients, minerals, and vitamins particularly in vegetarian, diabetic, or other specialized diets. PMID:26904610

Mineral Properties and Dietary Value of Raw and Processed Stinging Nettle (Urtica dioica L.

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Laban K. Rutto

2013-01-01

Full Text Available Stinging nettle (Urtica dioica L. has a long history of usage and is currently receiving attention as a source of fiber and alternative medicine. In many cultures, nettle is also eaten as a leafy vegetable. In this study, we focused on nettle yield (edible portion and processing effects on nutritive and dietary properties. Actively growing shoots were harvested from field plots and leaves separated from stems. Leaf portions (200 g were washed and processed by blanching (1 min at 96–98°C or cooking (7 min at 98-99°C with or without salt (5 g·. Samples were cooled immediately after cooking and kept in frozen storage before analysis. Proximate composition, mineral, amino acid, and vitamin contents were determined, and nutritive value was estimated based on 100 g serving portions in a 2000 calorie diet. Results show that processed nettle can supply 90%–100% of vitamin A (including vitamin A as β-carotene and is a good source of dietary calcium, iron, and protein. We recommend fresh or processed nettle as a high-protein, low-calorie source of essential nutrients, minerals, and vitamins particularly in vegetarian, diabetic, or other specialized diets.

Mineral Properties and Dietary Value of Raw and Processed Stinging Nettle (Urtica dioica L.).

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Rutto, Laban K; Xu, Yixiang; Ramirez, Elizabeth; Brandt, Michael

2013-01-01

Stinging nettle (Urtica dioica L.) has a long history of usage and is currently receiving attention as a source of fiber and alternative medicine. In many cultures, nettle is also eaten as a leafy vegetable. In this study, we focused on nettle yield (edible portion) and processing effects on nutritive and dietary properties. Actively growing shoots were harvested from field plots and leaves separated from stems. Leaf portions (200 g) were washed and processed by blanching (1 min at 96-98°C) or cooking (7 min at 98-99°C) with or without salt (5 g·L(-1)). Samples were cooled immediately after cooking and kept in frozen storage before analysis. Proximate composition, mineral, amino acid, and vitamin contents were determined, and nutritive value was estimated based on 100 g serving portions in a 2000 calorie diet. Results show that processed nettle can supply 90%-100% of vitamin A (including vitamin A as β-carotene) and is a good source of dietary calcium, iron, and protein. We recommend fresh or processed nettle as a high-protein, low-calorie source of essential nutrients, minerals, and vitamins particularly in vegetarian, diabetic, or other specialized diets.

Volatile compounds from leaves of the African spider plant (Gynandropsis gynandra) with bioactivity against spider mite (Tetranychus urticae)

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Nyalala, Samuel Odeyo; Petersen, Mikael Agerlin; Grout, Brian William Wilson

2013-01-01

Previous studies have demonstrated that Gynandropsis gynandra emits acetonitrile as a foliar volatile from intact plants and isolated leaves, and that this compound is an effective spider mite repellent. This study has used gas chromatography–mass spectrometry to investigate volatile compounds...... emitted from homogenised G. gynandra leaves to evaluate their tissue acetonitrile content and to look for other compounds that might be exploited for the management of spider mites. Acetonitrile was absent from the homogenised tissues of five lines of G. gynandra, studied over two seasons. Thirteen...... volatile compounds were emitted by G. gynandra at significantly higher levels than mite-susceptible pot roses, including isothiocyanates, aldehydes, esters, alcohols and terpenes. Six representative compounds were selected to assess bioactivity. Spider mite populations were completely inactive after a 2¿h...

Nephila clavata L Koch, the Joro Spider of East Asia, newly recorded from North America (Araneae: Nephilidae

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E. Richard Hoebeke

2015-02-01

Full Text Available Nephila clavata L Koch, known as the Joro spider and native to East Asia (Japan, China, Korea, and Taiwan, is newly reported from North America. Specimens from several locations in northeast Georgia were collected from around residential properties in Barrow, Jackson, and Madison counties in late October and early November 2014. These are the first confirmed records of the species in the New World. Our collections, along with confirmed images provided by private citizens, suggest that the Joro spider is established in northeast Georgia. Genomic sequence data for the COI gene obtained from two specimens conforms to published sequences for N. clavata, providing additional confirmation of species identity. Known collection records are listed and mapped using geocoding. Our observations are summarized along with published background information on biology in Asia and we hypothesize on the invasion history and mode of introduction into North America. Recognition features are given and photographic images of the male and female are provided to aid in their differentiation from the one native species of the genus (Nephila clavipes in North America.

Extraction and HPLC analysis of phenolic compounds in leaves, stalks, and textile fibers of Urtica dioica L.

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Pinelli, Patrizia; Ieri, Francesca; Vignolini, Pamela; Bacci, Laura; Baronti, Silvia; Romani, Annalisa

2008-10-08

In the present study the phenolic composition of leaves, stalks, and textile fiber extracts from Urtica dioica L. is described. Taking into account the increasing demand for textile products made from natural fibers and the necessity to create sustainable "local" processing chains, an Italian project was funded to evaluate the cultivation of nettle fibers in the region of Tuscany. The leaves of two nettle samples, cultivated and wild (C and W), contain large amounts of chlorogenic and 2- O-caffeoylmalic acid, which represent 71.5 and 76.5% of total phenolics, respectively. Flavonoids are the main class in the stalks: 54.4% of total phenolics in C and 31.2% in W samples. Anthocyanins are second in quantitative importance and are present only in nettle stalks: 28.6% of total phenolics in C and 24.4% in W extracts. Characterization of phenolic compounds in nettle extracts is an important result with regard to the biological properties (antioxidant and antiradical) of these metabolites for their possible applications in various industrial activities, such as food/feed, cosmetics, phytomedicine, and textiles.

Chitosan films incorporated with nettle (Urtica Dioica L.) extract-loaded nanoliposomes: II. Antioxidant activity and release properties.

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Almasi, Hadi; Zandi, Mohsen; Beigzadeh, Sara; Haghju, Sara; Mehrnow, Nazila

2016-07-14

Chitosan films were loaded with NE nettle (Urtica dioica L.) extract (NE) at concentrations of 0, 0.5, 1 and 1.5%w/w in the free or nanoliposomal form to obtain active and nanoactive films, respectively. The antioxidant potential of the films containing NE-loaded nanoliposomes was decreased in comparison of free NE incorporated films. Diffusion of NE to soybean oil was enough to delay the induction of the oxidation of soybean oil stored for 60 days in contact with chitosan based films. Release studies indicated that the release rate of NE in 95% ethanol simulant significantly decreased by the nanoencapsulation of NE. The diffusion coefficient (D) for chitosan films containing 1.5%w/w of free and encapsulated NE at 25 °C was 18.80 and 3.68 × 10 -7 cm 2  s -1 , respectively. Moreover, the formation of nanoliposomes diminished the increasing effect of temperature on the release rate as when storage temperature increased from 4 °C to 40 °C.

NUEVOS HOSPEDEROS Y REGISTROS DE ÁCAROS FITÓFAGOS PARA COSTA RICA: PERÍODO 2008-2012

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Hugo Aguilar

2012-01-01

Full Text Available Se actualizan las e especies de á caros fitó - fagos identificadas para Costa Rica entre 2008 y 2012. Se procesó el material vegetal provisto por productores, técnicos, estudiantes e interesados en general, así como el recolectado por personal del Laboratorio de Acarología de la Universidad de Costa Rica, y s e identificó. Se mencionan 63 nuevas especies e n 29 familias de plantas hos - pedantes, p ara 5 familias de ácaros fitófagos. Tetranychus urticae , familia Tetranychidae, fue la segunda especie en cuanto a número de h os - pederos, encontrándose e n 1 2 nuevas p antas. También s e hallaron o tras especies de la familia, como Eutetranychus banksi , Mononychellus planki , Oligonychus peronis , O. pratensis , O. punicae , O. ununguis , O. yothersi , Paraponychus corderoi , Tetranychus cinnabarinus , T. ludeni , T. mexicanus y 3 especies de este género que no fueron identificadas. S e registran 4 especies de la f amilia Tenuipalpidae: Brevipalpus californi - cus , B. gliricidiae , B. obovatus y B. phoenicis . Dentro de la familia Tarsonemidae, se informa de Phytonemus pallidus , Polyphagotarsonemus latus , con 15 nuevos registros, especie con mayor aporte en asociación con plantas para este nuevo período; s e informa también de Steneotarsone - musananas , asociada conpiña. De la familia Eriophyidae, se indica de Abacarus doctus, descrita recientemente como nueva especie p ara la ciencia y asociada con caña de azúcar en el país y de Calepitrimerus muesebecki , relaciona - da con aguacate; además 2 especies de eriófidos expuestos, no descritas aún. Retracrus johnstoni , familia Phytoptidae, recolectado de Heliconia latispatha , de la familia Heliconiaceae y primer registro de un ácaro de este género asociado con una planta ajena a la familia Arecaceae. Por último, se expone la descripción del reconocimiento de campo para algunas especies escogidas dentro de las 5 familias estudiadas.

Performance of Metarhizium anisopliae-treated foam in combination with Phytoseiulus longipes Evans on Tetranychus evansi Baker & Pritchard (Acari: Tetranychidae).

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Azandémè Hounmalon, Ginette Y; Maniania, Nguya K; Niassy, Saliou; Fellous, Simon; Kreiter, Serge; Delétré, Emilie; Fiaboe, Komi K; Martin, Thibaud

2018-05-13

Tetranychus evansi (Te) is an exotic pest of solanaceous crops in Africa. The predatory mite Phytoseiulus longipes (Pl) and the fungus Metarhizium anisopliae (Ma), are potential biocontrol agents of Te. The present study investigated efficacy of fungus-treated foam placed above or below the third Te-infested tomato leaf. The persistence of fungus-treated foam and the performance of Pl with or without fungus-treated foam were evaluated. The fungus-treated foam was effective when Te infestation was below the third tomato leaf as no damage was recorded on all upper tomato leaves up to 30 days post-treatment. However, in the control treatments, the infestation increased considerably from 9±0.3% to 100±0% at 15 days post-treatment. The reuse of the fungus-treated foam at 15, 30 and 45 days post-treatment resulted in 19±1.4%, 25±1.2% and 54±2.1% respective infestation by Te. The fungus-treated foam and Pl alone are efficient, but there is no benefit to combinting both against Te. The fungus-treated foam is an effective method to optimize the use of Ma in screenhouse conditions. These two control agents could be integrated in an IPM strategy for crops protection. However, these results need to be confirmed in large field trials. This article is protected by copyright. All rights reserved. This article is protected by copyright. All rights reserved.

Effect of Urtica dioica on memory dysfunction and hypoalgesia in an experimental model of diabetic neuropathy.

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Patel, Sita Sharan; Udayabanu, M

2013-09-27

Diabetic neuropathy is considered as a disease of the peripheral nervous system, but recent evidences suggest the involvement of central nervous system as well. In this study we evaluated the effect of Urtica dioica (UD) extract against memory dysfunction and hypoalgesia on a mouse model of streptozotocin (STZ) induced diabetic neuropathy. STZ (50 mg/kg, i.p. consecutively for 5 days) was used to induce diabetes, followed by treatment with the UD extract (50 mg/kg, oral) and rosiglitazone (5 mg/kg, oral) for 8 weeks. Cognitive functions were evaluated using Morris water maze and passive avoidance step through task. Pain thresholds were measured using thermal, mechanical and chemical induced hyperalgesia. We observed that chronic diabetes resulted in a decline in circulating insulin level, elevated blood glucose, reduced body weight, increased water intake, cognitive impairment and hypoalgesia. UD significantly reduced the blood glucose and polydypsia, as well as improved the body weight, insulin level, cognition and insensate neuropathy. In conclusion, UD showed results comparable to rosiglitazone in reversing the long standing diabetes induced complications such as central and peripheral neuronal dysfunction. Copyright © 2013 Elsevier Ireland Ltd. All rights reserved.

VARIABILIDAD MORFOLÓGICA MEDIANTE CARACTERES DE SEMILLA DE POBLACIONES DE Amelanchier denticulata (Kunth Koch, ORIGINARIAS DE GUANAJUATO, MÉXICO

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Miguel Ángel Hernández-Martínez

2011-01-01

Full Text Available El membrillo cimarrón (Amelanchier denticulata (Kunth Koch. es un arbusto frutal de la familia Rosaceae subtribu Pyrinae originario de México, del cual no existen estudios para conocer su diversidad ni su sistema reproductivo. Por estas razones y para tener un primer antecedente sobre su variabilidad morfológica, se caracterizaron seis poblaciones de A. denticulata originarias de Guanajuato, México, mediante caracteres de semilla. Todas las poblaciones presentaron alta variabilidad intra e interpoblacional. Las variables de semilla analizadas fueron discriminantes para distinguir las diferentes poblaciones, siendo las más importantes las relacionadas con las de tamaño de las semillas, seguidas de las de forma. El grado de apomixis no es claro en esta especie debido a la alta variación intrapoblacional; por lo tanto, se necesitan estudios más detallados para concluir la existencia o no de apomixis en A. denticulata.

Re-description of Xysticus bimaculatus L. Koch, 1867 (Araneae, Thomisidae and characterization of its subsocial lifestyle

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Jasmin Ruch

2014-07-01

Full Text Available Spiders have become an important model to study the evolution of sociality, but a lack of their detailed natural history and taxonomy hinders broader comparative studies. Group-living crab spiders (Thomisidae provide an excellent contrast to other social spiders since they lack a communal capture web, which was thought to be a critical factor in the evolution of sociality. Only three non-webbuilding crab-spider species are known to be subsocial or social, all of which belong to the genus Diaea Thorell, 1869. The aim of this study is to describe the social lifestyle of Xysticus bimaculatus L. Koch, 1867 for the first time. Furthermore, we present a detailed re-description of this species and discuss its taxonomic implications. Like other subsocial crab spiders, X. bimaculatus builds nests from tree leaves. Nests contain up to 38 spiders and sometimes several adult females, indicating the species may be at a transitory stage between subsociality and permanent sociality.

Seasonal variation in the populations of Polyphagotarsonemus latus and Tetranychus bastosi in physic nut (Jatropha curcas) plantations.

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Rosado, Jander F; Picanço, Marcelo C; Sarmento, Renato A; da Silva, Ricardo Siqueira; Pedro-Neto, Marçal; Carvalho, Marcos Alberto; Erasmo, Eduardo A L; Silva, Laila Cristina Rezende

2015-07-01

Studies on the seasonal variation of agricultural pest species are important for the establishment of integrated pest control programs. The seasonality of pest attacks on crops is affected by biotic and abiotic factors, for example, climate and natural enemies. Besides that, characteristics of the host plant, crop management, location and the pests' bioecology also affect this seasonality. The mites Polyphagotarsonemus latus (Prostigmata: Tarsonemidae) and Tetranychus bastosi (Prostigmata: Tetranychidae) are the most important pests in the cultivation of physic nut, Jatropha curcas (Euphorbiaceae). All parts of J. curcas can be used for a wide range of purposes. In addition many researchers have studied its potential for use as neat oil, as transesterified oil (biodiesel), or as a blend with diesel. However studies about physic nut pests have been little known. The objective of this study was to assess the seasonal variation of P. latus and T. bastosi in physic nut. This study was conducted at three sites in the state of Tocantins, Brazil. We monitored climatic elements and the densities of the two mite species and of their natural enemies for a period of 2 years. Attack by P. latus occurred during rainy seasons, when the photoperiod was short and the physic nut had new leaves. In contrast, attack by T. bastosi occurred during warmer seasons with longer photoperiods and stronger winds. Populations of both mites and their natural enemies were greater in sites with greater plant diversity adjacent to the plantations. The predators found in association with P. latus and T. bastosi were Euseius concordis (Acari: Phytoseiidae), spiders, Stethorus sp. (Coleoptera: Coccinellidae) and Chrysoperla sp. (Neuroptera: Chrysopidae).

Preferência do pulgão-preto, Aphis craccivora Koch, a diferentes genótipos de feijão-de-corda, Vigna unguiculata (L. Walp Black aphid, Aphis craccivora Koch, preference to different cowpea, Vigna unguiculata (L. Walp. cultivars

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João Gutemberg Leite Moraes

2007-12-01

Full Text Available Este trabalho foi desenvolvido visando a avaliar a resposta de cultivares de feijão-de-corda, Vigna unguiculata (L. Walp., à presença do pulgão-preto (Aphis craccivora Koch. Os experimentos foram conduzidos de agosto a outubro de 2004, em casa-de-vegetação da Universidade Federal do Ceará (UFC. As cultivares foram: "Epace-10", "Epace-11", "Patativa", "Pingo de Ouro", "Pitiúba", "BR-10 Piauí", "BR-12 Canindé", "BR-14 Mulato" e "BR-17 Gurguéia". O experimento constou de três ensaios, cada um com cinco tratamentos e seis repetições, sendo o delineamento estatístico inteiramente casualizado. Os genótipos foram cultivados em copos plásticos de 300ml e mantidos em gaiolas protegidas por tela antiafídeos. As plantas foram infestadas após doze dias do plantio através da liberação de cinco fêmeas adultas do pulgão-preto por planta. As avaliações foram realizadas após o terceiro e o quinto dia da infestação, constando da contagem direta das formas adulta e jovem do inseto presentes nas plantas. Os dados obtidos foram analisados através de análise de variância e pelo teste de Tukey em 5% de probabilidade de erro. As cultivares "Epace-10" e "Patativa" foram as menos preferidas por A. craccivora.This research was conducted with the intention of evaluating the response of different cowpea, Vigna unguiculata (L. Walp, cultivars to the black aphid (Aphis craccivora Koch. The bioassays were conducted from August through October of 2004 in a greenhouse at the Ceará Federal University (UFC campus. The cowpea cultivars used were: Epace-10, Epace-11, Patativa, Pingo de Ouro, Pitiúba, BR-10 Piauí, BR-12 Canindé, BR-14 Mulato and BR-17 Gurguéia. Each assay had five treatments and six replications in a completely randomized block design. The genotypes were raised in a 300ml plastic cup and maintained in cages protected by an insect proof net. Plants were infested twelve days after planting with five adult females per plant

Introducing Urtica dioica, A Native Plant of Khuzestan, As an Antibacterial Medicinal Plant.

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Motamedi, Hossein; Seyyednejad, Seyyed Mansour; Bakhtiari, Ameneh; Vafaei, Mozhan

2014-11-01

Urtica dioica is a flowering plant with long history of use in folk medicine and as a food source. This study examined in vitro antibacterial potential of alcoholic extracts of U. dioica. Hydroalcoholic extracts from aerial parts were prepared using aqueous solution of ethanol and methanol and their inhibitory effects against clinical isolates was examined by disc diffusion method at different doses. Minimum inhibitory concentrations (MIC) and minimum bactericidal concentration (MBC) indexes were also investigated. The scanning electron microscopy (SEM) analysis was also performed to find structural changes of affected bacteria consequent to exposing with extracts. Both extracts were active against Bacillus cereus, Staphylococcus aureus, Staphylococcus epidermidis, and Escherichia coli with respectively 16, 10, 18, and 14 mm (methanolic) and 11, 9, 17, and 16 mm (ethanolic) inhibition zone. The MIC of ethanolic extract against S. epidermidis and E. coli was respectively 10 and 40 mg/mL. The MIC of methanolic extract against S. aureus and S. epidermidis was 40 and 10 mg/mL, respectively. The MBC was found only for S. epidermidis (20 mg/mL). In SEM analysis the round shape of S. epidermidis was changed and irregular shapes were appeared, which suggest that the main target of these extracts was cell wall. Extracts of U. dioica showed significant antibacterial effect against some clinically important pathogenic bacteria. Based on the obtained results it can be concluded that U. dioica is useful as antibacterial and bactericidal agent in treating infectious diseases.

Nettle extract (Urtica dioica) affects key receptors and enzymes associated with allergic rhinitis.

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Roschek, Bill; Fink, Ryan C; McMichael, Matthew; Alberte, Randall S

2009-07-01

A nettle (Urtica dioica) extract shows in vitro inhibition of several key inflammatory events that cause the symptoms of seasonal allergies. These include the antagonist and negative agonist activity against the Histamine-1 (H(1)) receptor and the inhibition of mast cell tryptase preventing degranulation and release of a host of pro-inflammatory mediators that cause the symptoms of hay fevers. The nettle extract also inhibits prostaglandin formation through inhibition of Cyclooxygenase-1 (COX-1), Cyclooxygenase-2 (COX-2), and Hematopoietic Prostaglandin D(2) synthase (HPGDS), central enzymes in pro-inflammatory pathways. The IC(50) value for histamine receptor antagonist activity was 251 (+/-13) microg mL(-1) and for the histamine receptor negative agonist activity was 193 (+/-71) microg mL(-1). The IC(50) values for inhibition of mast cell tryptase was 172 (+/-28) microg mL(-1), for COX-1 was 160 (+/-47) microg mL(-1), for COX-2 was 275 (+/-9) microg mL(-1), and for HPGDS was 295 (+/-51) microg mL(-1). Through the use of DART TOF-MS, which yields exact masses and relative abundances of compounds present in complex mixtures, bioactives have been identified in nettle that contribute to the inhibition of pro-inflammatory pathways related to allergic rhinitis. These results provide for the first time, a mechanistic understanding of the role of nettle extracts in reducing allergic and other inflammatory responses in vitro. Copyright 2009 John Wiley & Sons, Ltd.

Urtica dioica leaves modulates muscarinic cholinergic system in the hippocampus of streptozotocin-induced diabetic mice.

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Patel, Sita Sharan; Parashar, Arun; Udayabanu, Malairaman

2015-06-01

Diabetes mellitus is a chronic metabolic disorder and has been associated with cognitive dysfunction. In our earlier study, chronic Urtica dioica (UD) treatment significantly ameliorated diabetes induced associative and spatial memory deficit in mice. The present study was designed to explore the effect of UD leaves extract on muscarinic cholinergic system, which has long been known to be involved in cognition. Streptozotocin (STZ) (50 mg/kg, i.p., consecutively for 5 days) was used to induce diabetes followed by treatment with UD extract (50 mg/kg, oral) or rosiglitazone (5 mg/kg, oral) for 8 weeks. STZ-induced diabetic mice showed significant reduction in hippocampal muscarinic acetylcholine receptor-1 and choline acetyltransferase expressions. Chronic diabetes significantly up-regulated the protein expression of acetylcholinesterase associated with oxidative stress in hippocampus. Besides, STZ-induced diabetic mice showed hypolocomotion with up-regulation of muscarinic acetylcholine receptor-4 expression in striatum. Chronic UD treatment significantly attenuated the cholinergic dysfunction and oxidative stress in the hippocampus of diabetic mice. UD had no effect on locomotor activity and muscarinic acetylcholine receptor-4 expression in striatum. In conclusion, UD leaves extract has potential to reverse diabetes mediated alteration in muscarinic cholinergic system in hippocampus and thereby improve memory functions.

Effects of Urtica dioica on oxidative stress, proliferation and apoptosis after partial hepatectomy in rats.

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Oguz, Serhat; Kanter, Mehmet; Erboga, Mustafa; Toydemir, Toygar; Sayhan, Mustafa Burak; Onur, Hatice

2015-05-01

The present study was performed to investigate the effect of Urtica dioica (UD) on liver regeneration after partial hepatectomy (PH) in rats. A total of 24 male Sprague Dawley rats were divided into three groups: sham-operated, PH and PH + UD; each group contains eight animals. The rats in UD-treated groups were given UD oils (2 ml/kg/day) once a day orally for 7 days starting 3 days prior to hepatectomy operation. At day 7 after resection, liver samples were collected. The levels of malondialdehyde (MDA), superoxide dismutase (SOD) and glutathione (GSH) were estimated in liver homogenates. Moreover, histopathological examination, mitotic index (MI), proliferating cell nuclear antigen labeling, proliferation index (PI), transferase-mediated deoxyuridine triphosphate nick end-labeling assay, apoptotic index (AI) were evaluated at day 7 after hepatectomy. As a result, UD significantly increased MI and PI, significantly decreased AI and also attenuated hepatic vacuolar degeneration and sinusoidal congestion in PH rats. UD treatment significantly decreased the elevated tissue MDA level and increased the reduced SOD activity and GSH level in the tissues. These results suggest that UD pretreatment was beneficial for rat liver regeneration after partial hepatectomy. © The Author(s) 2013.

Protective effects of Urtica dioica L. on experimental testicular ischaemia reperfusion injury in rats.

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Aktas, C; Erboga, M; Fidanol Erboga, Z; Bozdemir Donmez, Y; Topcu, B; Gurel, A

2017-05-01

In this study, it was aimed to examine the effects of Urtica dioica L. (UD) that has antioxidant feature in the experimental testicular I/R model in rats in terms of anti-apoptotic and antioxidative effects. In our study, 24 male rats were divided into three groups: control group, I/R group and I/R + UD (2 mg kg -1 ) group. Seminiferous tubule calibre measurement, Johnson score, haematoxylin-eosin staining, proliferative cell nucleus antigen (PCNA) immunohistochemical staining and TUNEL as histopathological have been conducted. The structural deterioration in the testicular on I/R group has reduced after the treatment of UD. Our data indicate a significant reduction in the activity of in situ identification of apoptosis using terminal dUTP nick end labelling (TUNEL), and there was a rise in the expression of proliferating cell nuclear antigen (PCNA) in testis tissues of UD-treated rats in the I/R group. The I/R + UD group showed a decrease in malondialdehyde levels and an increase in the activities of superoxide dismutase, catalase and glutathione peroxidase in comparison with the I/R group. It could be concluded that protective effects of UD on the I/R testicles are via reduction of histological damage, apoptosis, oxidative stress and lipid peroxidation. © 2016 Blackwell Verlag GmbH.

Arbuscular mycorrhizal infection in two morphological root types of Araucaria araucana (Molina K. Koch Infección por micorrizas arbusculares en dos tipos de raíces de Araucaria araucana (Molina K. Koch

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P. Diehl

2010-06-01

Full Text Available Araucaria araucana (Molina K. Koch is a conifer distributed in the Andean-Patagonian forests in the south of Argentina and Chile. The main objective of this work was to relate the different root classes appearing in A. araucana to mycorrhizal behavior. Samples were collected in three different sites in the Lanín National Park (NW Patagonia, Argentina. Two different root classes were present in A. araucana: longitudinal fine roots (LFR and globular short roots (GSR. Both had extensive mycorrhizal arbuscular symbiosis (AM and presented abundant hyphae and coils in root cells, a characteristic of the anatomical Paris-type. Dark septate fungal endophytes were also observed. Values of total AM colonization were high, with similar partial AM% values for each root class. Seasonal differences were found for total and partial colonization, with higher values in spring compared to autumn. Regarding the percentage of fungal structures between root classes, values were similar for vesicles and arbuscules, but higher coil percentages were observed in GSR compared to LFR. The percentages of vesicles increased in autumn, whereas the arbuscule percentages increased in spring, coinciding with the plant growth peak. Results show that both root classes of A. araucana in Andean-Patagonian forests are associated with AM fungi, which may have ecological relevance in terms of the importance of this symbiosis, in response to soil nutrient-deficiencies, especially high P-retention.La conífera Araucaria araucana (Molina K. Koch se encuentra distribuida en los bosques Andino-Patagónicos de Argentina y Chile. En este trabajo se relacionaron las diferentes clases morfológicas de raíces presentes en la especie con el comportamiento micorrícico. Las muestras fueron tomadas en tres sitios del Parque Nacional Lanín (NO de Patagonia, Argentina. Se observaron dos clases diferentes de raíces: raíces finas longitudinales (RFL y raíces cortas globulares (RCG. Ambas clases

The effect of temperature on the functional response of Phytoseiulus persimilis (Acari: Phytoseiidae).

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Skirvin, David J; Fenlon, John S

2003-01-01

Environmental variables, such as temperature, are important in determining the efficiency of biological control in ornamental crops. This paper examines the effect of temperature on the functional response of adult female Phytoseiulus persimilis to eggs of the spider mite, Tetranychus urticae. The functional response was determined using a new functional response assay technique with plant stems as an arena, rather than leaf discs. The use of plant stems allows the influence that plant structure has on predation to be incorporated into the assay. Control assays were also used (without predators) to estimate natural losses of prey. The data were analysed using a binomial model, with the use of Abbot's formula to correct for the losses in the controls. A combined equation to describe the effect of temperature and prey density on the predation rate of Phytoseiulus persimilis was derived. The results showed that more prey are eaten as the temperature increases from 15 degrees C to 25 degrees C, but the number of prey eaten then declines at 30 degrees C, although not to the levels seen at 20 degrees C. The implication of these results for biological control in ornamental crops, where the temperature can often exceed 30 degrees C, is discussed.

Behavioural responses of two-spotted spider mites induced by predator-borne and prey-borne cues.

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Gyuris, Enikő; Szép, Erna; Kontschán, Jenő; Hettyey, Attila; Tóth, Zoltán

2017-11-01

Applying predatory mites as biological control agents is a well established method against spider mites which are major pests worldwide. Although antipredator responses can influence the outcome of predator-prey interactions, we have limited information about what cues spider mites use to adjust their behavioural antipredator responses. We experimentally exposed two-spotted spider mites (Tetranychus urticae) to different predator-borne cues (using a specialist predator, Phytoseiulus persimilis, or a generalist predator, Amblyseius swirskii), conspecific prey-borne cues, or both, and measured locomotion and egg-laying activity. The reactions to predator species compared to each other manifested in reversed tendencies: spider mites increased their locomotion activity in the presence of P. persimilis, whereas they decreased it when exposed to A. swirskii. The strongest response was triggered by the presence of a killed conspecific: focal spider mites decreased their locomotion activity compared to the control group. Oviposition activity was not affected by either treatment. Our results point out that spider mites may change their behaviour in response to predators, and also to the presence of killed conspecifics, but these effects were not enhanced when both types of cues were present. The effect of social contacts among prey conspecifics on predator-induced behavioural defences is discussed. Copyright © 2017 Elsevier B.V. All rights reserved.

Use of lupin, Lupinus perennis, mango, Mangifera indica, and stinging nettle, Urtica dioica, as feed additives to prevent Aeromonas hydrophila infection in rainbow trout, Oncorhynchus mykiss (Walbaum).

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Awad, E; Austin, B

2010-05-01

Feeding rainbow trout, Oncorhynchus mykiss (Walbaum), with 1% lupin, Lupinus perennis, mango, Mangifera indica, or stinging nettle, Urtica dioica, for 14 days led to reductions in mortality after challenge with Aeromonas hydrophila. In addition, there was significant enhancement in serum bactericidal activity, respiratory burst and lysozyme activity in the treatment groups compared to the controls. Use of lupin and mango led to the highest number of red blood and white blood cells in recipient fish, with use of stinging nettle leading to the highest haematocrit and haemoglobin values; the highest value of mean corpuscular volume and haemoglobin was in the control groups and those fed with stinging nettle.

Can Urtica dioica supplementation attenuate mercury intoxication in Wistar rats?

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Siouda, Wafa; Abdennour, Cherif

2015-12-01

The objective of this study was to investigate the possible protective role of nettle Urtica dioica (UD) against Hg-induced toxicity. A total of 28 rats were equally divided into four groups: the control, the Hg (0.8 g HgCl2/kg in the diet), the UD (1.5 ml UD/rat by gavage), and the Hg+UD group. HgCl2 was daily dissolved in distilled water and immediately mixed with the standard diet. A solution of daily infused fresh nettle leaves in boiling water (16 g in 25 ml) was obtained and then it was administrated by gavage. Biochemical and reproductive markers, in addition to glutathione (GSH) level (liver, kidney and testis) and the histological profiles (testis and epididymis) were evaluated after 1 month exposure. Compared to the control, the levels of glucose, triglycerides, urea, creatinine, alanine aminotransferase (ALT), aspartate aminotransferase (AST), and alkaline phosphatase (ALP) were significantly raised in the Hg group. In the latter group, the concentrations of Mg, Fe, and Ca were significantly decreased. Besides, Hg+UD group has only showed raised AST activity and reduced Mg level. Concerning the fertility markers, Hg has provoked a significant decrease in the spermatozoa's concentration and motility and in plasma testosterone level as well. Furthermore, hepatic, renal and testicular GSH concentrations have declined significantly in the Hg treated rat compared to the control. A remarkable enhancement of the GSH level was observed in all organs of the UD group. The histological examinations of the Hg group have revealed marked testicular degeneration of the most seminiferous tubules, and showed few sperms in the lumen of epididymis ducts. However, the Hg+UD rats have demonstrated an improved histological structure with the presence of important numbers of sperms in the lumen. In addition, a clear stabilization of organized seminiferous tubules and an increased sperms' numbers were noted in the UD supplemented rats. Nettle leaves have not only played a clear

Quantitative determination of plant phenolics in Urtica dioica extracts by high-performance liquid chromatography coupled with tandem mass spectrometric detection.

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Orčić, Dejan; Francišković, Marina; Bekvalac, Kristina; Svirčev, Emilija; Beara, Ivana; Lesjak, Marija; Mimica-Dukić, Neda

2014-01-15

A method for quantification of 45 plant phenolics (including benzoic acids, cinnamic acids, flavonoid aglycones, C- and O-glycosides, coumarins, and lignans) in plant extracts was developed, based on reversed phase HPLC separation of extract components, followed by tandem mass spectrometric detection. The phenolic profile of 80% MeOH extracts of the stinging nettle (Urtica dioica L.) herb, root, stem, leaf and inflorescence was obtained by using this method. Twenty-one of the investigated compounds were present at levels above the reliable quantification limit, with 5-O-caffeoylquinic acid, rutin and isoquercitrin as the most abundant. The inflorescence extracts were by far the richest in phenolics, with the investigated compounds amounting 2.5-5.1% by weight. As opposed to this, the root extracts were poor in phenolics, with only several acids and derivatives being present in significant amounts. The results obtained by the developed method represent the most detailed U. dioica chemical profile so far. Copyright © 2013 Elsevier Ltd. All rights reserved.

Screening of analgesic activity of Tunisian Urtica dioica and analysis of its major bioactive compounds by GCMS.

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Dhouibi, Raouia; Moalla, Dorsaf; Ksouda, Kamilia; Ben Salem, Maryem; Hammami, Serria; Sahnoun, Zouheir; Zeghal, Khaled Mounir; Affes, Hanen

2017-11-20

The present study was aimed to evaluate the analgesic properties of Urtica dioica (UD) and to profile phytochemicals by gas chromatography-mass spectrometry (GC-MS). The ethanolic extracts were prepared by maceration method and extraction using rotary evaporator. The analgesic activity was analysed by hot plate method, formalin test, acetic acid-induced writhing test and the tail-flick test with different doses of the ethanolic extract. In all tests, the leaf's ethanolic extract exhibited significant analgesic activity (p analgesic activity with many tests. The GC-MS analysis of the ethanol extract of leaf revealed many compounds; 2-methyltetradecane dodecane, 2,6,11-trimethyl-; 2,6,11-trimethyldodecane, and trimethylhexane which are pharmaceutically the most important. These findings justify that UD can be a valuable natural analgesic source which seemed to provide potential phototherapeutics against various ailments. The analysis of ethanolic extract of UD by GCMS revealed the presence of several compounds including polyphenols, flavonoids, triterpenes which can explain the analgesic effect of UD and its mechanism of action. Hence, UD could be another therapeutic alternative for relieving pain and for minimising the use of drugs that have long-term secondary effects.

Gamma irradiation as a quarantine treatment of apples infested with diapausing eggs of the European red spider mite, Panonychus ulmi (Koch) (Acarina: Tetranychidae)

International Nuclear Information System (INIS)

Ignatowicz, S.

1997-01-01

Viable eggs of the European red mite, Panonychus ulmi (Koch), on apples have been the concern of several importing countries and exports require preshipment, phytosanitary treatment to reduce or eliminate live eggs. Because fumigation is often detrimental to the commodity appearance and shelf-life, resulting in a loss of commercial value, there is a need for alternatives for chemical pest control as a quarantine treatment, and irradiation could be a new strategy method. The data obtained indicate that a dose of gamma radiation equal to or higher than 0.15 kGy seems to be adequate to prevent post-diapause hatching of wintering eggs of the European red mite. Thus, this dose is suggested for quarantine treatment of apples infested with wintering eggs of the European red mite. (author)

Effect of different temperatures on reproductive performance of Scolothrips longicornis reared on Tetranychus urticae eggs

DEFF Research Database (Denmark)

Pakyari, Hajar; Enkegaard, Annie

2012-01-01

Reproductive parameters for Scolothrips longicornis were determined and compared at six temperatures (15, 20, 26, 30, 35 and 37°C), 60 ± 10% relative humidity and a photoperiod of 16:8 h (light:dark). Reproductive parameters were estimated for individual newly emerged thrips, which had spent...

The effect of extracts of the roots of the stinging nettle (Urtica dioica) on the interaction of SHBG with its receptor on human prostatic membranes.

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Hryb, D J; Khan, M S; Romas, N A; Rosner, W

1995-02-01

Extracts from the roots of the stinging nettle (Urtica dioica) are used in the treatment of benign prostatic hyperplasia. The mechanisms underlying this treatment have not been elucidated. We set out to determine whether specific extracts from U. dioica had the ability to modulate the binding of sex hormone-binding globulin to its receptor on human prostatic membranes. Four substances contained in U. dioica were examined: an aqueous extract; an alcoholic extract; U. dioica agglutinin, and stigmasta-4-en-3-one. Of these, only the aqueous extract was active. It inhibited the binding of 125I-SHBG to its receptor. The inhibition was dose related, starting at about 0.6 mg/ml and completely inhibited binding at 10 mg/ml.

Ameliorative influence of Urtica dioica L against cisplatin-induced toxicity in mice bearing Ehrlich ascites carcinoma.

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Özkol, Halil; Musa, Davut; Tuluce, Yasin; Koyuncu, Ismail

2012-07-01

Cisplatin (CP) is a widely used cytotoxic agent against cancer, and high doses of CP have been known to cause nephrotoxicity and hepatotoxicity. Some reports claim that antioxidants can reduce CP-induced toxicity. This study investigated the hepatoprotective, nephroprotective, and antioxidant activity of Urtica dioica L methanolic extract (UDME) against CP toxicity in Erhlich ascites tumor (EAT)-bearing mice. Levels of serum hepatic enzymes, renal function markers, and oxidant/antioxidant parameters of liver tissue were measured. Mice were inoculated with EAT on day 0 and treated with nothing else for 24 hours. After a single dose of CP administration on day 1, the extract was given at the doses of 50, 100, 200, and 400 mg/kg body weight daily during 6 days. Almost all doses of UDME performed a significant (P < 0.05) preventive role against CP toxicity by decreasing aspartate aminotransferase, alanine aminotransferase, lactate dehydrogenase, blood urea nitrogen, creatinine, lipid peroxidation, protein oxidation levels, and myeloperoxidase activity, as well as increasing reduced glutathione content, superoxide dismutase, catalase, glutathione S-transferase, and glutathione peroxidase activities. This suggests that UDME has a protective capacity and antioxidant activity against CP toxicity in EAT-bearing mice, probably by promoting antioxidative defense systems.

Disease prevalence and transmission of Microsporidium phytoseiuli infecting the predatory mite, Phytoseiulus persimilis (Acari: Phytoseiidae).

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Bjørnson, S; Keddie, B A

2001-02-01

Isolated colonies of the predatory mite, Phytoseiulus persimilis, were used to gain information regarding prevalence and transmission of Microsporidium phytoseiuli. Two colonies of P. persimilis were reared on spider mite (Tetranychus urticae)-infested bean plants in isolated cages. Disease prevalence of predators from Colony 1 remained relatively low (between 0 and 15%) over 57 weeks of observation whereas disease prevalence of predators from Colony 2 increased over 3 months (from 12 to 100%). Disease prevalence among predators from Colony 1 had increased to 100% 2 months after weekly sampling had ceased for this colony and periodic sampling confirmed that disease prevalence among individuals of both colonies remained at 100%. Microsporidian spores were not detected in randomly chosen samples of T. urticae prey mites that were removed and examined biweekly during this period. Although numerous microsporidian spores were observed in smear preparations of fecal pellets examined by light microscopy, spores were not observed on leaf surfaces or predator feces when examined by SEM. The latter appeared as intact aggregates composed of numerous dumbbell-shaped crystals and it is unlikely that spores are liberated from intact fecal pellets onto leaf surfaces. Vertical transmission of M. phytoseiuli was 100%; horizontal transmission was low (14.3%) and occurred only when immature P. persimilis were permitted to develop in contact with infected immature and adult predators. The mean number of eggs produced per mated pair was highest when uninfected females were mated with uninfected males (63.2 eggs per mated pair). Although mean egg production decreased when one or both parents were infected, not all differences were significant. Male predatory mites did not contribute to infection of their progeny. Results suggest that routine examination of P. persimilis for microsporidian spores is essential for the management of M. phytoseiuli within P. persimilis colonies. Low disease

Obituary: Robert H. Koch (1929-2010)

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Koch, Joanne; Corcoran, Michael; Holenstein, Bruce; Sion, Edward

2011-12-01

Robert H. Koch, emeritus professor of astronomy and astrophysics at the University of Pennsylvania, passed away at his home in Ardmore, Pennsylvania on 11 October 2010 after a brief illness. Bob was 80 years old and remained sharp and intellectually engaged with the astronomical community up until the onset of complications from a brain tumor. Bob was born in York, Pennsylvania on 19 December 1929, and graduated from York Catholic High School in 1947. He attended the University of Pennsylvania on a senatorial scholarship, graduating in 1951. After two years in the United States Army, he enrolled in graduate school at the University of Pennsylvania, doing his doctoral research on the photoelectric photometry of R CMa, AO Cas, AS Eri, and XY Leo at the Steward Observatory, University of Arizona in Tucson. Bob would continue this exploration of close binary stars, their atmospheres and interactions, for the rest of his career. Bob met his future spouse, Joanne C. Underwood, while in graduate school in 1957 and they were married in 1959. Bob received his PhD in astronomy in 1959 and moved to Amherst, Massachusetts, where he taught as a member of the Four College Astronomy Department until 1966. Following a year at the University of New Mexico in Albuquerque, Bob joined the Astronomy Department at Penn, teaching and doing research there until his retirement in 1996. Bob's main interests were the study of close and eclipsing binary stars, stellar envelopes and winds, intrinsic variables, transits and occultations, and the Milky Way Galaxy, producing well over 100 refereed publications. Bob was partial to photoelectric photometry and polarimetry, conducting most of his observational research at the University of Pennsylvania Flower and Cook Observatory, and at other ground- and space-based observatories. As an international figure in the area of binary stars, Bob had widespread collaborations with scientists at other institutions, in the US and throughout the world, and

Mugwort (Artemisia L., nettle (Urtica L. and plantain (Plantago L. pollen in the atmosphere of Wrocław in the years 2002-2004

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Małgorzata Malkiewicz

2012-12-01

Full Text Available The paper includes the results of pollen season analysis of the selected plants (mugwort, nettle, plantain regarded as the most allergenic in Wrocław in 2002-2004. The studies were carried out using volumetric method (Burkard trap. The results show strong variation in pollen seasons. The average duration of the pollen season of Artemisia was 82 days. The highest pollen concentration of mugwort was recorded in 2004 (156 grains × m-3. The start of nettle pollen seasons varied in studied period on average by 24 days, on average, but its end was almost the same. The pollen season of Urtica was the earliest in 2004. It started on 5th May and lasted 136 days. The annual pollen total of Plantago was relatively low, on average 0.2-0.4% in annual pollen totals.

Seleção para alto teor de acilaçúcares em genótipos de tomateiro e sua relação com a resistência ao ácaro vermelho (Tetranychus evansi e à traça (Tuta absoluta Selection towards high acylsugar levels in tomato genotypes and its relationship with resistance to spider mite (Tetranychus evansi and to the South American pinworm (Tuta absoluta

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Guilherme Victor Nippes Pereira

2008-06-01

Full Text Available Uma das estratégias do melhoramento do tomateiro, no Brasil, visando à resistência a pragas, tem sido a utilização de aleloquímicos presentes nos folíolos. Objetivou-se no presente trabalho, estudar os níveis de resistência a dois artrópodos-pragas [traça do tomateiro (Tuta absoluta e ácaros (Tetranychus evansi], em genótipos previamente selecionados com base apenas no seu teor foliar de acilaçúcares. Foram selecionadas 11 plantas contrastantes quanto aos níveis de acilaçúcares nos folíolos, de uma população F3RC2, derivada do cruzamento interespecífico Lycopersicon esculentum Mill 'TOM-584' x Lycopersicon pennellii (Correll D'Arcy 'LA-716'. Esses genótipos, juntamente com os genitores TOM-584 e LA-716, foram submetidos a ensaios de repelência/resistência a artrópodos-pragas. No teste de repelência ao ácaro T. evansi, as plantas com altos teores de acilaçúcares se comportaram de forma semelhante ao genitor resistente LA-716. As magnitudes das correlações foram negativas e significativas, confirmando assim a associação entre altos teores do aleloquímico e a resistência (repelência ao ácaro, avaliada pela distância percorrida. No ensaio realizado com a traça do tomateiro, os genótipos foram avaliados para danos nas plantas e lesões nos folíolos. Os genótipos contendo alto teor de acilaçúcares, demonstraram bons níveis de resistência a Tuta absoluta, não diferindo significativamente do acesso selvagem LA-716. Em todas as épocas de avaliação, os teores de acilaçúcares mostraram-se alta e negativamente correlacionados com os níveis de dano causados pela traça. Os resultados obtidos comprovaram a eficiência da seleção de genótipos de tomateiro com elevados teores de acilaçúcares nos folíolos, visando à resistência a artrópodos-praga.Selection for high foliar levels of allelochemicals has been proposed as a suitable strategy for breeding tomatoes for arthropod pest resistance. In the

2D FTIR correlation spectroscopy and EPR analysis of Urtica dioica leaves from areas of different environmental pollution

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Moskal, Paulina; Wesełucha-Birczyńska, Aleksandra; Łabanowska, Maria; Kurdziel, Magdalena; Filek, Maria

2018-01-01

Leaves of Urtica dioica collected from two areas of different environmental pollution were analysed by fourier transform infrared spectroscopy (FTIR) and electron paramagnetic resonance (EPR) spectroscopy. Analysis of FTIR spectra allows to describe main component of plant like proteins, lipids and carbohydrates. Although the FTIR spectra of plants from these two geographical locations of different environmental pollution appear to be relatively similar, 2D correlation shows completely different patterns. Synchronous and asynchronous correlation maps showed sequences of changes occurring during development of plant, manly in Amide I and Amide II, lignin, lipids and cellulose. In addition, 2D analysis revealed another sequence of changes as the function of plant growth depending on the degree of the environmental pollution. Two various kinds of paramagnetic species, transition metal ions (Mn(II), Fe(III)) and stable organic radicals (chlorophyll, semiquinone, tyrosyl and carbon centered) were found in leaves of nettle collected at different stages of development and growing in clean and polluted environment. In plants growing in polluted area the injuries of protein molecules bonding metal ions and the disturbances of photosynthesis and redox equilibrium in cells, as well as instability of polysaccharide structure of cell walls were observed.

The role of detoxifying enzymes in the resistance of the cowpea aphid (Aphis craccivora Koch to thiamethoxam

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Abdallah Ibrahim Saleh

2016-01-01

Full Text Available The cowpea aphid (Aphis craccivora Koch is considered a serious insect pest attacking several crops. We carried out biochemical studies to elucidate the role of the metabolising enzymes in conferring resistance to thiamethoxam, in two strains (resistant and susceptible of the cowpea aphid. Bioassay experiments showed that the thiamethoxam selected strain developed a 48 fold resistance after consecutive selection with thiamethoxam for 12 generations. This resistant strain also exhibited cross-resistance to the tested carbamates; pirimicarb and carbosulfan, organophosphorus (malathion, fenitrothion, and chlorpyrifos-methyl, and the neonicotinoid (acetamiprid. Synergism studies have indicated that S,S,S-tributyl phosphorotrithioate (DEF, a known inhibitor for esterases, increased thiamethoxam toxicity 5.58 times in the resistant strain compared with the susceptible strain. Moreover, the biochemical determination revealed that carboxylestersae activity was 30 times greater in the resistant strain than in the susceptible strain. In addition, the enzyme activity of glutathione S-transferase (GST and mixed function oxidases (mfo increased only in the resistant strain 3.7 and 2.7 times, respectively, in relation to the susceptible (the control. Generally, our results suggest that the higher activity of the detoxifying enzymes, particularly carboxylesterase, in the resistant strain of the cowpea aphid, apparently have a significant role in endowing resistance to thiamethoxam, although additional mechanisms may contribute.

Screening antimicrobial activity of various extracts of Urtica dioica.

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Modarresi-Chahardehi, Amir; Ibrahim, Darah; Fariza-Sulaiman, Shaida; Mousavi, Leila

2012-12-01

Urtica dioica or stinging nettle is traditionally used as an herbal medicine in Western Asia. The current study represents the investigation of antimicrobial activity of U. dioica from nine crude extracts that were prepared using different organic solvents, obtained from two extraction methods: the Soxhlet extractor (Method I), which included the use of four solvents with ethyl acetate and hexane, or the sequential partitions (Method II) with a five solvent system (butanol). The antibacterial and antifungal activities of crude extracts were tested against 28 bacteria, three yeast strains and seven fungal isolates by the disc diffusion and broth dilution methods. Amoxicillin was used as positive control for bacteria strains, vancomycin for Streptococcus sp., miconazole nitrate (30 microg/mL) as positive control for fungi and yeast, and pure methanol (v/v) as negative control. The disc diffusion assay was used to determine the sensitivity of the samples, whilst the broth dilution method was used for the determination of the minimal inhibition concentration (MIC). The ethyl acetate and hexane extract from extraction method I (EA I and HE I) exhibited highest inhibition against some pathogenic bacteria such as Bacillus cereus, MRSA and Vibrio parahaemolyticus. A selection of extracts that showed some activity was further tested for the MIC and minimal bactericidal concentrations (MBC). MIC values of Bacillus subtilis and Methicillin-resistant Staphylococcus aureus (MRSA) using butanol extract of extraction method II (BE II) were 8.33 and 16.33mg/mL, respectively; while the MIC value using ethyl acetate extract of extraction method II (EAE II) for Vibrio parahaemolyticus was 0.13mg/mL. Our study showed that 47.06% of extracts inhibited Gram-negative (8 out of 17), and 63.63% of extracts also inhibited Gram-positive bacteria (7 out of 11); besides, statistically the frequency of antimicrobial activity was 13.45% (35 out of 342) which in this among 21.71% belongs to

Screening antimicrobial activity of various extracts of Urtica dioica

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Amir Modarresi-Chahardehi

2012-12-01

Full Text Available Urtica dioica or stinging nettle is traditionally used as an herbal medicine in Western Asia. The current study represents the investigation of antimicrobial activity of U. dioica from nine crude extracts that were prepared using different organic solvents, obtained from two extraction methods: the Soxhlet extractor (Method I, which included the use of four solvents with ethyl acetate and hexane, or the sequential partitions (Method II with a five solvent system (butanol. The antibacterial and antifungal activities of crude extracts were tested against 28 bacteria, three yeast strains and seven fungal isolates by the disc diffusion and broth dilution methods. Amoxicillin was used as positive control for bacteria strains, vancomycin for Streptococcus sp., miconazole nitrate (30µg/mL as positive control for fungi and yeast, and pure methanol (v/v as negative control. The disc diffusion assay was used to determine the sensitivity of the samples, whilst the broth dilution method was used for the determination of the minimal inhibition concentration (MIC. The ethyl acetate and hexane extract from extraction method I (EA I and HE I exhibited highest inhibition against some pathogenic bacteria such as Bacillus cereus, MRSA and Vibrio parahaemolyticus. A selection of extracts that showed some activity was further tested for the MIC and minimal bactericidal concentrations (MBC. MIC values of Bacillus subtilis and Methicillin-resistant Staphylococcus aureus (MRSA using butanol extract of extraction method II (BE II were 8.33 and 16.33mg/mL, respectively; while the MIC value using ethyl acetate extract of extraction method II (EAE II for Vibrio parahaemolyticus was 0.13mg/mL. Our study showed that 47.06% of extracts inhibited Gram-negative (8 out of 17, and 63.63% of extracts also inhibited Gram-positive bacteria (7 out of 11; besides, statistically the frequency of antimicrobial activity was 13.45% (35 out of 342 which in this among 21.71% belongs to

Protective effects of Urtica dioica seed extract in aflatoxicosis: histopathological and biochemical findings.

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Uyar, A; Yener, Z; Dogan, A

2016-04-01

The ameliorative potential and antioxidant capacity of an extract of Urtica dioica seeds (UDS) was investigated using histopathological changes in liver and kidney, measuring serum marker enzymes, antioxidant defence systems and lipid peroxidation (malondialdehyde (MDA)) content in various tissues of broilers exposed to aflatoxin (AF). A total of 32 broilers were divided randomly into 4 groups: control, UDS extract-treated, AF-treated and AF+UDS extract-treated. Broilers in control and UDS extract-treated groups were fed on a diet without AF. The AF-treated group and AF+UDS extract-treated groups were treated with an estimated 1 mg total AF/kg feed. The AF+UDS extract groups received in addition 30 ml UDS extract/kg diet for 21 d. The AF-treated group had significantly decreased body weight gain when compared to the other groups. Biochemical analysis showed a small increase in the concentrations of serum aspartate aminotransferase, alanine aminotransferase, gamma glutamyl transpeptidase and lactate dehydrogenase in the AF-treated group compared to that of the control group, whereas concentrations of these enzymes were decreased in the AF+UDS group compared to that of the AF-treated group. Administration of supplementary UDS extract helped restore the AF-induced increase in MDA and reduced the antioxidant system towards normality, particularly in the liver, brain, kidney and heart. Hepatorenal protection by UDS extracts was further supported by the almost normal histology in AF+UDS extract-treated group as compared to the degenerative changes in the AF-treated broilers. It was concluded that UDS extract has a protective hepatorenal effect in broilers affected by aflatoxicosis, probably acting by promoting the antioxidative defence systems.

Protective effects of nettle (Urtica dioica extract against acute kidney injury induced by gentamycin in the rat

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سید پژمان مرتضوی

2017-11-01

Full Text Available Aminoglycosides are often used in combination with beta-lactam antibiotics and have a rapid bactericidal effect, are available at an affordable cost and have less incidence of resistance, making them a drug of choice for treatment of several life-threatening infections. However, the nephrotoxic effects of aminoglycosides prevent their long term use. The use of herbal extracts in order to decrease injuries of injurious materials has long been considered. The present study was conducted in order to investigate the protective effects of nettle (Urtica dioica extract against gentamicin induced kidney injuries in the rat. Forty five male Wistar rats were divided into 9 groups consisting of: 1-healthy control group, 2- negative control group that received tween 20 (extract solvent, 3- patient control group which received onlygentamicin at 100 mg/kg, experimental healthy groups 4-6 which received nettle extract at 50, 100 and 200 mg/kg and patient experimental groups 7-9 which received nettle extract along with gentamicin at 100 mg/kg. At the end of the experiment (28 days, blood samples were obtained, and the kidneys were removed for histopathologic investigations. The results showed that gentamicin alone induced renal tissue damage and significantly increased the serum levels of creatinine and urea (p

Effect of Urtica Dioica Extract on Histological and Histometrical Changes of Testis of Hamster after Testosteron Administration

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Hassan Morovvati

2013-11-01

Full Text Available Background: Hyperactivity of testosterone is one cause of infertility and its incorrect use can produces reproductive disorders. Nettle (Urtica dioica has antiandrogenic effect and may antagonized effect of testosterone. In present study structure of testes of golden hamster was evaluated after testosterone and extract. Materials and Methods: In this experimental and animal modeling study, twenty male mature hamsters were divided to 4 groups, group 1 was control, group 2 received testosterone at dose 3 mg/kg subcutaneously, group 3 received nettle extract dose 30 mg/kg orally and group 4 received testosterone and nettle for 30 days daily. The hamsters were euthanized and testes were removed and detected macroscopic parameters (weight, height, wide and volume and fixed with formalin. The samples were sectioned and colored with H & E. Results: The volume, weight, length and wide of testes was at least in testosterone group and statistically was lesser than control and testosterone -nettle group (p<0.05, but did not the height epithelium of seminifer tubules, compact of spermatogenic cells and number of serotolli cells in testosterone group was lesser than control group significantly (p<0.05.Conclusion: The nettle extract decreased histological changes of testes by testosterone and improved its structure.

Can Urtica dioica supplementation attenuate mercury intoxication in Wistar rats?

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Wafa Siouda

2015-12-01

Full Text Available Aim: The objective of this study was to investigate the possible protective role of nettle Urtica dioica (UD against Hg-induced toxicity. Materials and Methods: A total of 28 rats were equally divided into four groups: the control, the Hg (0.8 g HgCl2/kg in the diet, the UD (1.5 ml UD/rat by gavage, and the Hg+UD group. HgCl2 was daily dissolved in distilled water and immediately mixed with the standard diet. A solution of daily infused fresh nettle leaves in boiling water (16 g in 25 ml was obtained and then it was administrated by gavage. Biochemical and reproductive markers, in addition to glutathione (GSH level (liver, kidney and testis and the histological profiles (testis and epididymis were evaluated after 1 month exposure. Results: Compared to the control, the levels of glucose, triglycerides, urea, creatinine, alanine aminotransferase (ALT, aspartate aminotransferase (AST, and alkaline phosphatase (ALP were significantly raised in the Hg group. In the latter group, the concentrations of Mg, Fe, and Ca were significantly decreased. Besides, Hg+UD group has only showed raised AST activity and reduced Mg level. Concerning the fertility markers, Hg has provoked a significant decrease in the spermatozoa’s concentration and motility and in plasma testosterone level as well. Furthermore, hepatic, renal and testicular GSH concentrations have declined significantly in the Hg treated rat compared to the control. A remarkable enhancement of the GSH level was observed in all organs of the UD group. The histological examinations of the Hg group have revealed marked testicular degeneration of the most seminiferous tubules, and showed few sperms in the lumen of epididymis ducts. However, the Hg+UD rats have demonstrated an improved histological structure with the presence of important numbers of sperms in the lumen. In addition, a clear stabilization of organized seminiferous tubules and an increased sperms’ numbers were noted in the UD

The effect of stinging nettle (Urtica dioica) seed oil on experimental colitis in rats.

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Genc, Zeynep; Yarat, Aysen; Tunali-Akbay, Tugba; Sener, Goksel; Cetinel, Sule; Pisiriciler, Rabia; Caliskan-Ak, Esin; Altıntas, Ayhan; Demirci, Betul

2011-12-01

This study investigated the effect of Urtica dioica, known as stinging nettle, seed oil (UDO) treatment on colonic tissue and blood parameters of trinitrobenzene sulfonic acid (TNBS)-induced colitis in rats. Experimental colitis was induced with 1 mL of TNBS in 40% ethanol by intracolonic administration with a 8-cm-long cannula with rats under ether anesthesia, assigned to a colitis group and a colitis+UDO group. Rats in the control group were given saline at the same volume by intracolonic administration. UDO (2.5 mL/kg) was given to the colitis+UDO group by oral administration throughout a 3-day interval, 5 minutes later than colitis induction. Saline (2.5 mL/kg) was given to the control and colitis groups at the same volume by oral administration. At the end of the experiment macroscopic lesions were scored, and the degree of oxidant damage was evaluated by colonic total protein, sialic acid, malondialdehyde (MDA), and glutathione levels, collagen content, tissue factor activity, and superoxide dismutase and myeloperoxidase activities. Colonic tissues were also examined by histological and cytological analysis. Pro-inflammatory cytokines (tumor necrosis factor-α, interleukin-1β, and interleukin-6), lactate dehydrogenase activity, and triglyceride and cholesterol levels were analyzed in blood samples. We found that UDO decreased levels of pro-inflammatory cytokines, lactate dehydrogenase, triglyceride, and cholesterol, which were increased in colitis. UDO administration ameliorated the TNBS-induced disturbances in colonic tissue except for MDA. In conclusion, UDO, through its anti-inflammatory and antioxidant actions, merits consideration as a potential agent in ameliorating colonic inflammation.

Urtica dioica attenuates ovalbumin-induced inflammation and lipid peroxidation of lung tissues in rat asthma model.

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Zemmouri, Hanene; Sekiou, Omar; Ammar, Sonda; El Feki, Abdelfattah; Bouaziz, Mohamed; Messarah, Mahfoud; Boumendjel, Amel

2017-12-01

To find bioactive medicinal herbs exerting anti-asthmatic activity, we investigated the effect of an aqueous extract of Urtica dioica L. (Urticaceae) leaves (UD), the closest extract to the Algerian traditional use. In this study, we investigated the in vivo anti-asthmatic and antioxidant activities of nettle extract. Adult male Wistar rats were divided into four groups: Group I: negative control; group II: Ovalbumin sensitized/challenged rats (positive control); group III: received UD extract (1.5 g/kg/day) orally along the experimental protocol; group IV: received UD extract (1.5 g/kg/day) orally along the experimental protocol and sensitized/challenged with ovalbumin. After 25 days, blood and tissue samples were collected for haematological and histopathological analysis, respectively. The oxidative stress parameters were evaluated in the lungs, liver and erythrocytes. Then, correlations between markers of airway inflammation and markers of oxidative stress were explored. UD extract significantly (p nettle extract was also investigated for the total phenolic content (30.79 ± 0.96 mg gallic acid/g dry extract) and shows DPPH radical scavenging activity with 152.34 ± 0.37 μg/mL IC 50 value. The results confirmed that UD administration might be responsible for the protective effects of this extract against airway inflammation.

Antifungal activity of nettle (Urtica dioica L.), colocynth (Citrullus colocynthis L. Schrad), oleander (Nerium oleander L.) and konar (Ziziphus spina-christi L.) extracts on plants pathogenic fungi.

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Hadizadeh, I; Peivastegan, B; Kolahi, M

2009-01-01

Anti-mycotic activity of the ethanol extracts from Nettle (Urtica dioica L.), Colocynth (Citrullus colocynthis L. Schrad), Konar (Ziziphus spina-christi L.) and Oleander (Nerium oleander L.) floral parts were screened in vitro against four important plant pathogenic fungi viz.; Alternaria alternate, Fusarium oxysporum, Fusarium solani and Rizoctonia solani using agar dilution bioassay. Extracts showed antifungal activity against all the tested fungi. Among the plants, Nettle and Colocynth were the most effective against A. alternate and R. solani while Oleander possesses the best inhibition on F. oxysporum and F. solani. Konar was the most effective extract by reducing the growth of Rizoctonia solani than other fungi. These results showed that extracts could be considered suitable alternatives to chemical additives for the control of fungal diseases in plants.

DISTRIBUCIÓN Y CARACTERIZACIÓN ECO-CLIMÁTICA DEL MEMBRILLO CIMARRÓN (Amelanchier denticulata (Kunth Koch EN MÉXICO.

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Carlos Alberto Núñez-Colín

2010-01-01

Full Text Available El membrillo cimarrón (Amelanchier denticulata (Kunth Koch es un arbusto frutal nativo de México, del cual no existen suficientes estudios sobre su uso, distribución y diversidad. Este estudio tuvo como objetivo hacer un modelo de distribución, una caracterización eco-climática así como modelos actual y futuro de zonas adecuadas de cultivo de A. denticulata con el uso de Sistemas de Información Geográfica (SIG. El membrillo cimarrón se distribuyó principalmente en el centro de México. Se obtuvieron tres grupos climáticos, el grupo 1 presentó un clima C, el grupo 2, un clima A(C, y el grupo 3, un clima Bs. Las regiones más adecuadas de cultivo fueron Guanajuato, Querétaro e Hidalgo. Los tres diferentes grupos climáticos pueden tener germoplasma diverso, por lo que es importante colectar en cada uno de ellos. Las mejores regiones para establecer un banco de germoplasma in vivo son el noreste de Guanajuato, centro y sur de Querétaro y el sur de Hidalgo.

Synthesis and characterization of an effective organic/inorganic hybrid green corrosion inhibitive complex based on zinc acetate/Urtica Dioica

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Salehi, E.; Naderi, Reza; Ramezanzadeh, B.

2017-02-01

This study aims at synthesis and characterization of an effective corrosion inhibitive complex based on zinc acetate/Urtica Dioica (ZnA-U.D) for corrosion protection of mild steel in chloride solution. The chemical structure and morphology of the complex were characterized by Fourier transform infrared spectroscopy (FT-IR), UV-vis, thermal gravimetric analysis (TGA), X-ray photoelectron spectroscopy (XPS) and scanning electron microscopy (SEM). The corrosion protection performance of the mild steel samples dipped in 3.5 wt.% NaCl solutions with and without ZnA-U.D extract was investigated by visual observations, open circuit potential (OCP) measurements, electrochemical impedance spectroscopy (EIS) and polarization test. Results revealed that the ZnA successfully chelated with organic inhibitive compounds (i.e Quercetin, Quinic acid, Caffeic acid, Hystamine and Serotonin) present in the U.D extract. The electrochemical measurements revealed the effective inhibition action of ZnA-U.D complex in the sodium chloride solution on the mild steel. The synergistic effect between Zn2+ and organic compounds present in the U.D extract resulted in protective film deposition on the steel surface, which was proved by SEM and XPS analyses.

Dynamic evolution and biogenesis of small RNAs during sex reversal.

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Liu, Jie; Luo, Majing; Sheng, Yue; Hong, Qiang; Cheng, Hanhua; Zhou, Rongjia

2015-05-06

Understanding origin, evolution and functions of small RNA (sRNA) genes has been a great challenge in the past decade. Molecular mechanisms underlying sexual reversal in vertebrates, particularly sRNAs involved in this process, are largely unknown. By deep-sequencing of small RNA transcriptomes in combination with genomic analysis, we identified a large amount of piRNAs and miRNAs including over 1,000 novel miRNAs, which were differentially expressed during gonad reversal from ovary to testis via ovotesis. Biogenesis and expressions of miRNAs were dynamically changed during the reversal. Notably, phylogenetic analysis revealed dynamic expansions of miRNAs in vertebrates and an evolutionary trajectory of conserved miR-17-92 cluster in the Eukarya. We showed that the miR-17-92 cluster in vertebrates was generated through multiple duplications from ancestor miR-92 in invertebrates Tetranychus urticae and Daphnia pulex from the Chelicerata around 580 Mya. Moreover, we identified the sexual regulator Dmrt1 as a direct target of the members miR-19a and -19b in the cluster. These data suggested dynamic biogenesis and expressions of small RNAs during sex reversal and revealed multiple expansions and evolutionary trajectory of miRNAs from invertebrates to vertebrates, which implicate small RNAs in sexual reversal and provide new insight into evolutionary and molecular mechanisms underlying sexual reversal.

An analysis of radiation-induced damage in the spider mite. Relationship between mortality of haploid and diploid eggs in two successive generations

International Nuclear Information System (INIS)

Leenhouts, H.P.; Chadwick, K.H.

1976-01-01

Unfertilized females of the spider mite (Tetranychus urticae) produce only haploid eggs which develop into a haploid male. Fertilized females produce both haploid eggs (unfertilized), which develop into males, and diploid eggs (fertilized), which develop into females. Radiobiological experiments performed by A.M. Feldmann (Association Euratom-ITAL) made data available on the radiation-induced mortality of haploid and diploid eggs in the F 1 and F 2 generation following irradiation of either males or females with X rays or fast neutrons. The data have been analysed using the molecular theory of cell survival where it is assumed that DNA double strand breaks, induced randomly in the cell, are the critical radiation-induced lesions, which lead to cell death. Theoretical relationships are derived for the dose dependence of hatchability in haploid and diploid eggs in the first and second generations expressed as a function of the radiation damage in the parental genome. These theoretical relationships can be used to derive the inter-relationship between the different hatchabilities, and the results from the spider mite have been analysed using these considerations. It is concluded that the radiation-induced genetic damage arises from one type of initial lesion. The eventual radiobiological implications of this analysis are discussed, expecially with respect to the transmittance of radiation-induced genetic damage after low-level radiation. (author)

The economic importance of acaricides in the control of phytophagous mites and an update on recent acaricide mode of action research.

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Van Leeuwen, Thomas; Tirry, Luc; Yamamoto, Atsushi; Nauen, Ralf; Dermauw, Wannes

2015-06-01

Acaricides are one of the cornerstones of an efficient control program for phytophagous mites. An analysis of the global acaricide market reveals that spider mites such as Tetranychus urticae, Panonychus citri and Panonychus ulmi are by far the most economically important species, representing more than 80% of the market. Other relevant mite groups are false spider mites (mainly Brevipalpus), rust and gall mites and tarsonemid mites. Acaricides are most frequently used in vegetables and fruits (74% of the market), including grape vines and citrus. However, their use is increasing in major crops where spider mites are becoming more important, such as soybean, cotton and corn. As revealed by a detailed case study of the Japanese market, major shifts in acaricide use are partially driven by resistance development and the commercial availability of compounds with novel mode of action. The importance of the latter cannot be underestimated, although some compounds are successfully used for more than 30 years. A review of recent developments in mode of action research is presented, as such knowledge is important for devising resistance management programs. This includes spirocyclic keto-enols as inhibitors of acetyl-CoA carboxylase, the carbazate bifenazate as a mitochondrial complex III inhibitor, a novel class of complex II inhibitors, and the mite growth inhibitors hexythiazox, clofentezine and etoxazole that interact with chitin synthase I. Copyright © 2014 Elsevier Inc. All rights reserved.

Suppression of Plant Defenses by Herbivorous Mites Is Not Associated with Adaptation to Host Plants

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Jéssica T. Paulo

2018-06-01

Full Text Available Some herbivores suppress plant defenses, which may be viewed as a result of the coevolutionary arms race between plants and herbivores. However, this ability is usually studied in a one-herbivore-one-plant system, which hampers comparative studies that could corroborate this hypothesis. Here, we extend this paradigm and ask whether the herbivorous spider-mite Tetranychus evansi, which suppresses the jasmonic-acid pathway in tomato plants, is also able to suppress defenses in other host plants at different phylogenetic distances from tomatoes. We test this using different plants from the Solanales order, namely tomato, jimsonweed, tobacco, and morning glory (three Solanaceae and one Convolvulaceae, and bean plants (Fabales. First, we compare the performance of T. evansi to that of the other two most-commonly found species of the same genus, T. urticae and T. ludeni, on several plants. We found that the performance of T. evansi is higher than that of the other species only on tomato plants. We then showed, by measuring trypsin inhibitor activity and life history traits of conspecific mites on either clean or pre-infested plants, that T. evansi can suppress plant defenses on all plants except tobacco. This study suggests that the suppression of plant defenses may occur on host plants other than those to which herbivores are adapted.

[Associating Serenoa repens, Urtica dioica and Pinus pinaster. Safety and efficacy in the treatment of lower urinary tract symptoms. Prospective study on 320 patients].

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Pavone, C; Abbadessa, D; Tarantino, M L; Oxenius, I; Laganà, A; Lupo, A; Rinella, M

2010-01-01

Serenoa repens (saw palmetto) has been employed for the treatment of lower urinary tract symptoms (LUTS) for several years. Its mechanism of action is believed to be due to antiandrogenic, antiproliferative and antinflammatory properties. An association of Serenoa with the nettle "Urtica dioica" showing antiproliferative activity and the pine "Pinus pinaster" derivative, showing antinflammatory action, has been proposed in recent years. Such an action is hoped to act not only by reducing LUTS but also by preventing the development of prostate cancer. During the years 2007 and 2008, 320 patients suffering from LUTS were treated with an association of Serenoa repens 320 mg, Urtica dioica 120 mg and Pinus pinaster 5 mg, named IPBTRE. This treatment was administered to all patients for a minimal duration of 30 days to a maximum of a year, either alone or in association with antibiotics or alpha-blockers, if needed. Outcome analysis was based on evaluation of symptoms, prostate volume and maximum flow rate (Qmax). From a careful analysis of the data collected in our database, the following observations can be made: ages varied between 19 and 78 years. The patients were affected by BPH in 46% of cases, chronic prostatitis syndrome in 43%, chronic genital-pelvic pain in 7% and other conditions in 4%, the absolute numbers being 147, 138, 22 and 7 patients, respectively. No untoward side effect was reported in any case. Variations in symptom score could be fully evaluated only in 80 of 320 patients (25%), of whom 68 (85%) reported a significant benefit, with special reference to an improvement of pain, urgency, strangury and nocturia. Data on variations in prostate volume, as measured by digital rectal examination, were available in 84 (26.5%) patients. No significant change was observed. Qmax after treatment was measured in 83 (26%) patients. It did not show significant changes from the initial values. The association tested in our study appeared to be safe and well

Microstructural homogeneity of support silk spun by Eriophora fuliginea (C.L. Koch) determined by scanning X-ray microdiffraction

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Riekel, C.; Craig, C. L.; Burghammer, M.; Müller, M.

2001-01-01

Scanning X-ray microdiffraction (SXD) permits the 'imaging' in-situ of crystalline phases, crystallinity and texture in whole biopolymer samples on the micrometre scale. SXD complements transmission electron microscopy (TEM) techniques, which reach sub-nanometre lateral resolution but require thin sections and a vacuum environment. This is demonstrated using a support thread from a web spun by the orb-weaving spider Eriophora fuliginea (C.L. Koch). Scanning electron microscopy (SEM) shows a central thread composed of two fibres to which thinner fibres are loosely attached. SXD of a piece of support thread approximately 60 µm long shows in addition the presence of nanometre-sized crystallites with the β-poly(L-alanine) structure in all fibres. The crystallinity of the thin fibres appears to be higher than that of the central thread, which probably reflects a higher polyalanine content of the fibroins. The molecular axis of the polymer chains in the central thread is orientated parallel to the macroscopic fibre axis, but in the thin fibres the molecular axis is tilted by about 71° to the macroscopic fibre axis. A helical model is tentatively proposed to describe this morphology. The central thread has a homogeneous distribution of crystallinity along the macroscopic fibre axis.

2D FTIR correlation spectroscopy and EPR analysis of Urtica dioica leaves from areas of different environmental pollution.

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Moskal, Paulina; Wesełucha-Birczyńska, Aleksandra; Łabanowska, Maria; Kurdziel, Magdalena; Filek, Maria

2018-01-15

Leaves of Urtica dioica collected from two areas of different environmental pollution were analysed by fourier transform infrared spectroscopy (FTIR) and electron paramagnetic resonance (EPR) spectroscopy. Analysis of FTIR spectra allows to describe main component of plant like proteins, lipids and carbohydrates. Although the FTIR spectra of plants from these two geographical locations of different environmental pollution appear to be relatively similar, 2D correlation shows completely different patterns. Synchronous and asynchronous correlation maps showed sequences of changes occurring during development of plant, manly in Amide I and Amide II, lignin, lipids and cellulose. In addition, 2D analysis revealed another sequence of changes as the function of plant growth depending on the degree of the environmental pollution. Two various kinds of paramagnetic species, transition metal ions (Mn(II), Fe(III)) and stable organic radicals (chlorophyll, semiquinone, tyrosyl and carbon centered) were found in leaves of nettle collected at different stages of development and growing in clean and polluted environment. In plants growing in polluted area the injuries of protein molecules bonding metal ions and the disturbances of photosynthesis and redox equilibrium in cells, as well as instability of polysaccharide structure of cell walls were observed. Copyright © 2017 Elsevier B.V. All rights reserved.

Effect of fertilizer application on Urtica dioica and its element concentrations in a cut grassland

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Müllerová, Vladimíra; Hejcman, Michal; Hejcmanová, Pavla; Pavlů, Vilém

2014-08-01

Little is known about the effects of nutrient availability in cut grasslands on growth characteristics of Urtica dioica and its aboveground chemical composition (N, P, K, Ca, Mg, Cu, Fe, Mn and Zn). The effects of N, P and K application on the growth of U. dioica were studied over five years in a Dactylis glomerata grassland cut twice per year under unfertilized control, P, N, NP and NPK treatments (300, 80 and 200 kg of N, P and K ha-1 per year). Nitrogen application in the form of NH4NO3 over five years decreased the soil pH, while P and K application increased P and K availability in the soil. Over five years, cover of U. dioica increased from 1% initially to 7, 9, 58, 83 and 99% in the control, P, N, NP and NPK treatments, respectively. Concentrations of N, P and Ca in the aboveground biomass of U. dioica were very high in comparison to other species and concentrations of Cu, Fe, Mn and Zn were comparable with other grassland species. N and P limitation of U. dioica growth was expected if concentrations of N and P in the aboveground biomass were lower than 25 g N kg-1 and 4 g P kg-1 in the phenological stage of flowering. We concluded that two cuts per year are not sufficient to suppress expansion of U. dioica under high N, P and K availability. This probably explains why U. dioica survive also in frequently cut intensive grasslands under adequately high nutrient supply.

Characterization of silver nanoparticles synthesized using Urtica dioica Linn. leaves and their synergistic effects with antibiotics

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Kumari Jyoti

2016-07-01

Full Text Available In continuation of the efforts for synthesizing silver nanoparticles (AgNPs by green chemistry route, here we report a facile bottom-up ‘green’ route for the synthesis of AgNPs using aqueous leaves extract of Urtica dioica (Linn.. The synthesized AgNPs were characterized by UV-vis spectroscopy, X-ray diffraction (XRD, Fourier transform-infrared spectroscopy (FTIR, Zeta-sizer and Zeta-potential, Scanning electron microscopy (SEM, Energy dispersive X-ray (EDX spectroscopy, Transmission electron microscopy (TEM and Selected area electron diffraction (SAED. The results obtained from various characterizations revealed that AgNPs were in the size range of 20–30 nm and crystallized in face-centered-cubic structure. The antibacterial activity against Gram-positive (Bacillus cereus, Bacillus subtilis, Staphylococcus aureus and Staphylococcus epidermidis and Gram-negative (Escherichia coli, Klebsiella pneumoniae, Serratia marcescens and Salmonella typhimurium bacterial pathogens was demonstrated by synthesized nanoparticles. Further, synergistic effects of AgNPs with various antibiotics were evaluated against above mentioned bacterial pathogens. The results showed that AgNPs in combination with antibiotics have better antibacterial effect as compared with AgNPs alone and hence can be used in the treatment of infectious diseases caused by bacteria. The maximum effect, with a 17.8 fold increase in inhibition zone, was observed for amoxicillin with AgNPs against S. marcescens proving the synergistic role of AgNPs. Therefore, it may be used to augment the activities of antibiotics.

Mites fluctuation population on peach tree (Prunus persica (L. Batsch and in associated plants Flutuação populacional de ácaros na cultura do pessegueiro (Prunus persica (L. Batsch e em plantas associadas

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Carla Rosana Eichelberger

2011-09-01

Full Text Available Despite the importance of peach (Prunus persica (L. Batsch in Rio Grande do Sul, little is known about mites fluctuation population considered important to this crop. The objective of this study was to know the population diversity and fluctuation of mite species associated with Premier and Eldorado varieties in Roca Sales and Venâncio Aires counties, Rio Grande do Sul. The study was conducted from July 2008 to June 2009 when 15 plants were randomly chosen in each area. The plants were divided in quadrants and from each one a branch was chosen from which three leaves were removed: one collected in the apical region, another in the medium and the other in the basal region, totalizing 180 leaves/area. Five of the most abundant associated plants were collected monthly in enough amounts for the screening under the stereoscopic microscope during an hour. A total of 1,124 mites were found belonging to 14 families and 28 species. Tetranychus ludeni Zacher, 1913, Panonychus ulmi (Koch, 1836 and Mononychellus planki (McGregor, 1950 were the most abundant phytophagous mites, whereas Typhlodromalus aripo Deleon, 1967 and Phytoseiulus macropilis (Banks, 1904 the most common predatory mites. The period of one hour under stereoscopic microscope was enough to get a representative sample. In both places evaluated the ecologic indices were low, but little higherin Premier (H' 0.56; EqJ: 0.43 when compared to Eldorado (H' 0.53; EqJ 0.40. In Premier constant species were not observed and accessory only Brevipalpus phoenicis (Geijskes, 1939, T. ludeni and T. aripo. Higher abundance was observed in December and January and bigger amount in April. Already in Eldorado, T. ludeni and P. ulmi were constants. Greater abundance was observed in November and December, whereas grater richness in December and January. In both orchards were not found mites in buds. Tetranychus ludeni is the most abundant phytophagous mites with outbreak population in November, December and

Effect of pruning and trellising of tomatoes on red spider mite ...

African Journals Online (AJOL)

Key Words: Arthropod pest, Lycopersicon esculentum, Tetranychus evansi. RÉSUMÉ La petite araignée rouge, Tetranychus evansi Baker & Prichard accidentellement introduite en Afrique Australe vers 1980 est une peste relativement nouvelle pour la tomate (Lycopersicon esculentum) de l'Afrique. Depuis lors l'espèce ...

Food-chain transfer of zinc from contaminated Urtica dioica and Acer pseudoplatanus L. to the aphids Microlophium carnosum and Drepanosiphum platanoidis Schrank

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Sinnett, Danielle, E-mail: danielle.sinnett@forestry.gsi.gov.u [Centre for Forestry and Climate Change, Forest Research, Alice Holt Lodge, Farnham, Surrey GU10 4LH (United Kingdom); Department of Soil Science, School of Human and Environmental Sciences, University of Reading, Whiteknights, Reading RG6 6DW (United Kingdom); Hutchings, Tony R., E-mail: tony.hutchings@forestry.gsi.gov.u [Centre for Forestry and Climate Change, Forest Research, Alice Holt Lodge, Farnham, Surrey GU10 4LH (United Kingdom); Hodson, Mark E., E-mail: m.e.hodson@reading.ac.u [Department of Soil Science, School of Human and Environmental Sciences, University of Reading, Whiteknights, Reading RG6 6DW (United Kingdom)

2010-01-15

This study examines the food-chain transfer of Zn from two plant species, Urtica dioica (stinging nettle) and Acer pseudoplatanus (sycamore maple), into their corresponding aphid species, Microlophium carnosum and Drepanosiphum platanoidis. The plants were grown in a hydroponic system using solutions with increasing concentrations of Zn from 0.02 to 41.9 mg Zn/l. Above-ground tissue concentrations in U. dioica and M. carnosum increased with increasing Zn exposure (p < 0.001). Zn concentrations in A. pseudoplatanus also increased with solution concentration from the control to the 9.8 mg Zn/l solution, above which concentrations remained constant. Zn concentrations in both D. platanoidis and the phloem tissue of A. pseudoplatanus were not affected by the Zn concentration in the watering solution. It appears that A. pseudoplatanus was able to limit Zn transport in the phloem, resulting in constant Zn exposure to the aphids. Zn concentrations in D. platanoidis were around three times those in M. carnosum. - Concentrations of Zn in two aphid species are dependant on species and exposure.

Food-chain transfer of zinc from contaminated Urtica dioica and Acer pseudoplatanus L. to the aphids Microlophium carnosum and Drepanosiphum platanoidis Schrank

International Nuclear Information System (INIS)

Sinnett, Danielle; Hutchings, Tony R.; Hodson, Mark E.

2010-01-01

This study examines the food-chain transfer of Zn from two plant species, Urtica dioica (stinging nettle) and Acer pseudoplatanus (sycamore maple), into their corresponding aphid species, Microlophium carnosum and Drepanosiphum platanoidis. The plants were grown in a hydroponic system using solutions with increasing concentrations of Zn from 0.02 to 41.9 mg Zn/l. Above-ground tissue concentrations in U. dioica and M. carnosum increased with increasing Zn exposure (p < 0.001). Zn concentrations in A. pseudoplatanus also increased with solution concentration from the control to the 9.8 mg Zn/l solution, above which concentrations remained constant. Zn concentrations in both D. platanoidis and the phloem tissue of A. pseudoplatanus were not affected by the Zn concentration in the watering solution. It appears that A. pseudoplatanus was able to limit Zn transport in the phloem, resulting in constant Zn exposure to the aphids. Zn concentrations in D. platanoidis were around three times those in M. carnosum. - Concentrations of Zn in two aphid species are dependant on species and exposure.

Screening antimicrobial activity of various extracts of Urtica dioica

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Amir Modarresi-Chahardehi

2012-12-01

Full Text Available Urtica dioica or stinging nettle is traditionally used as an herbal medicine in Western Asia. The current study represents the investigation of antimicrobial activity of U. dioica from nine crude extracts that were prepared using different organic solvents, obtained from two extraction methods: the Soxhlet extractor (Method I, which included the use of four solvents with ethyl acetate and hexane, or the sequential partitions (Method II with a five solvent system (butanol. The antibacterial and antifungal activities of crude extracts were tested against 28 bacteria, three yeast strains and seven fungal isolates by the disc diffusion and broth dilution methods. Amoxicillin was used as positive control for bacteria strains, vancomycin for Streptococcus sp., miconazole nitrate (30µg/mL as positive control for fungi and yeast, and pure methanol (v/v as negative control. The disc diffusion assay was used to determine the sensitivity of the samples, whilst the broth dilution method was used for the determination of the minimal inhibition concentration (MIC. The ethyl acetate and hexane extract from extraction method I (EA I and HE I exhibited highest inhibition against some pathogenic bacteria such as Bacillus cereus, MRSA and Vibrio parahaemolyticus. A selection of extracts that showed some activity was further tested for the MIC and minimal bactericidal concentrations (MBC. MIC values of Bacillus subtilis and Methicillin-resistant Staphylococcus aureus (MRSA using butanol extract of extraction method II (BE II were 8.33 and 16.33mg/mL, respectively; while the MIC value using ethyl acetate extract of extraction method II (EAE II for Vibrio parahaemolyticus was 0.13mg/mL. Our study showed that 47.06% of extracts inhibited Gram-negative (8 out of 17, and 63.63% of extracts also inhibited Gram-positive bacteria (7 out of 11; besides, statistically the frequency of antimicrobial activity was 13.45% (35 out of 342 which in this among 21.71% belongs to

Uncertainties in predicting species distributions under climate change: a case study using Tetranychus evansi (Acari: Tetranychidae), a widespread agricultural pest.

Science.gov (United States)

Meynard, Christine N; Migeon, Alain; Navajas, Maria

2013-01-01

Many species are shifting their distributions due to climate change and to increasing international trade that allows dispersal of individuals across the globe. In the case of agricultural pests, such range shifts may heavily impact agriculture. Species distribution modelling may help to predict potential changes in pest distributions. However, these modelling strategies are subject to large uncertainties coming from different sources. Here we used the case of the tomato red spider mite (Tetranychus evansi), an invasive pest that affects some of the most important agricultural crops worldwide, to show how uncertainty may affect forecasts of the potential range of the species. We explored three aspects of uncertainty: (1) species prevalence; (2) modelling method; and (3) variability in environmental responses between mites belonging to two invasive clades of T. evansi. Consensus techniques were used to forecast the potential range of the species under current and two different climate change scenarios for 2080, and variance between model projections were mapped to identify regions of high uncertainty. We revealed large predictive variations linked to all factors, although prevalence had a greater influence than the statistical model once the best modelling strategies were selected. The major areas threatened under current conditions include tropical countries in South America and Africa, and temperate regions in North America, the Mediterranean basin and Australia. Under future scenarios, the threat shifts towards northern Europe and some other temperate regions in the Americas, whereas tropical regions in Africa present a reduced risk. Analysis of niche overlap suggests that the current differential distribution of mites of the two clades of T. evansi can be partially attributed to environmental niche differentiation. Overall this study shows how consensus strategies and analysis of niche overlap can be used jointly to draw conclusions on invasive threat

Uncertainties in predicting species distributions under climate change: a case study using Tetranychus evansi (Acari: Tetranychidae, a widespread agricultural pest.

Directory of Open Access Journals (Sweden)

Christine N Meynard

Full Text Available Many species are shifting their distributions due to climate change and to increasing international trade that allows dispersal of individuals across the globe. In the case of agricultural pests, such range shifts may heavily impact agriculture. Species distribution modelling may help to predict potential changes in pest distributions. However, these modelling strategies are subject to large uncertainties coming from different sources. Here we used the case of the tomato red spider mite (Tetranychus evansi, an invasive pest that affects some of the most important agricultural crops worldwide, to show how uncertainty may affect forecasts of the potential range of the species. We explored three aspects of uncertainty: (1 species prevalence; (2 modelling method; and (3 variability in environmental responses between mites belonging to two invasive clades of T. evansi. Consensus techniques were used to forecast the potential range of the species under current and two different climate change scenarios for 2080, and variance between model projections were mapped to identify regions of high uncertainty. We revealed large predictive variations linked to all factors, although prevalence had a greater influence than the statistical model once the best modelling strategies were selected. The major areas threatened under current conditions include tropical countries in South America and Africa, and temperate regions in North America, the Mediterranean basin and Australia. Under future scenarios, the threat shifts towards northern Europe and some other temperate regions in the Americas, whereas tropical regions in Africa present a reduced risk. Analysis of niche overlap suggests that the current differential distribution of mites of the two clades of T. evansi can be partially attributed to environmental niche differentiation. Overall this study shows how consensus strategies and analysis of niche overlap can be used jointly to draw conclusions on invasive

Susceptibility of geographically isolated populations of the Tomato red spider mite (Tetranychus evansi Baker & Pritchard to commonly used acaricides on tomato crops in Kenya

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F. J. Toroitich

2014-04-01

Full Text Available Farmers in Kenya continue to raise concerns of difficulty in managing Tetranychus evansi, the most widespread pest species of tomato applying the most commonly used acaricides. This invasive pest species is not only found in Kenya, but in Eastern and Southern Africa, as well as parts of Europe and Asia. In the current study, populations of T. evansi were collected from farms in the four major tomato-growing areas of Kenya (Loitoktok, Kibwezi, Athi-River and Subukia and their susceptibility compared to a laboratory culture (ICIPE that had been maintained for three years without exposure to acaricides. Susceptibility of T. evansi eggs and adults (contact and residual to Brigade (bifenthrin, Dimethoate (dimethoate, Karate (lambdacyhalothrin, Kelthane (dicofol, Omite (propargite and Polytrin (profenofos+ cypermethrin was tested in the laboratory using respective manufacturer’s recommended concentrations. Dimethoate resulted in variable ovicidal mortality while Kelthane, Brigade, Karate, Omite and Polytrin had high mortality across all populations. Similarly, adult contact and residual mortality was lower than that of the other chemicals when exposed to Dimethoate regardless of the location. Furthermore, it also had no residual effect on the mites from ICIPE and Kibwezi. On the other hand, Kelthane was most lethal against the mites from all locations followed by Brigade and Polytrin in that order. Omite caused significantly lower mortality on mites from Subukia while Karate produced variable effects on mites from Kibwezi, Loitoktok and Subukia. The implications of these findings are further discussed.

Chemical Characterization and Release of Polyphenols from Pecan Nut Shell [Carya illinoinensis (Wangenh) C. Koch] in Zein Microparticles for Bioactive Applications.

Science.gov (United States)

Kureck, Itamara; Policarpi, Priscila de Brito; Toaldo, Isabela Maia; Maciel, Matheus Vinícius de Oliveira Brisola; Bordignon-Luiz, Marilde T; Barreto, Pedro Luiz Manique; Block, Jane Mara

2018-05-03

The pecan nut [Carya illinoinensis (Wangenh) C. Koch] is a natural source of polyphenols with antioxidant properties. In this study, the encapsulation of aqueous and hydroalcoholic extracts of pecan nut shell were evaluated for the release of bioactive compounds and antioxidant potential in order to explore food applications using zein as encapsulating agent. The extracts showed high contents of total phenolics, condensed tannins and high antioxidant activity. Concentrations of proanthocyanidins were 9-fold higher in hydroalcoholic extracts. The LC-DAD analysis showed that catechins were the major phenolic compounds in samples, with epigallocatechin levels up to 138.62 mg mL -1 . Zein microparticles loaded with aqueous extract released 2.3 times more phenolic compounds than the hydroalcoholic extracts and the DSC thermograms showed that extracts of pecan nut shell remained thermally stable up to 240 °C. The zein microcapsules obtained in this study were efficiently encapsulated and represent an interesting additive due its high antioxidant capacity, physicochemical characteristics and morphology. The use of zein microparticles combined with natural extracts constitute a step forward in the improvement of current technology for delivering phenolic compounds with applications in functional foods and nutraceuticals.

Synergism effects of pioglitazone and Urtica dioica extract in streptozotocin-induced nephropathy via attenuation of oxidative stress

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Mohammad Shokrzadeh

2017-05-01

Full Text Available Objective(s: Hyperglycemia promotes oxidative stress that plays a crucial role in the pathogenesis of Diabetic nephropathy (DN. In this study, we investigated the synergism effects of hydroalcoholic extract of Urtica dioica and pioglitazone (PIO on the prevention of DN in streptozotocin induced-diabetic mice. Materials and Methods: Forty-two mice were divided into six groups as follows: non-diabetic control group, DMSO group (as solvent, diabetic group and four treatment groups which received U. dioica, pioglitazone, U. dioica plus pioglitazone and vitE. Diabetes was induced by a single dose of streptozotocin (STZ (200 mg/kg body wt, IP diluted in citrate buffer (pH= 4.6. After 4 weeks treatment, all animals were anaesthetized and blood was collected for serum urea and creatinine levels assessment in plasma and kidney tissue were excised for evaluation of oxidative stress markers. Results: Treatment with U. dioica significantly inhibited increase in serum urea and creatinine in plasma that were observed in diabetic mice. Furthermore, the elevated level of oxidative stress markers (glutathione oxidation, lipid peroxidation (LPO, protein carbonyl in renal supernatant of diabetic mice was inhibited by U. dioica treatment.  Interestingly, U. dioica promoted beneficial effects of PIO in reducing STZ-induced hyperglycemia, renal damage and oxidative stress markers. Conclusion: Our findings showed that PIO plus U. dioica have synergism protective effects against STZ-induced nephropathy that can be a candidate as a therapeutic approach in order to treatment of DN.

Synergism effects of pioglitazone and Urtica dioica extract in streptozotocin-induced nephropathy via attenuation of oxidative stress.

Science.gov (United States)

Shokrzadeh, Mohammad; Sadat-Hosseini, Sara; Fallah, Marjan; Shaki, Fatemeh

2017-05-01

Hyperglycemia promotes oxidative stress that plays a crucial role in the pathogenesis of Diabetic nephropathy (DN). In this study, we investigated the synergism effects of hydroalcoholic extract of Urtica dioica and pioglitazone (PIO) on the prevention of DN in streptozotocin induced-diabetic mice. Forty-two mice were divided into six groups as follows: non-diabetic control group, DMSO group (as solvent), diabetic group and four treatment groups which received U. dioica , pioglitazone, U. dioica plus pioglitazone and vitE. Diabetes was induced by a single dose of streptozotocin (STZ) (200 mg/kg body wt, IP) diluted in citrate buffer (pH= 4.6). After 4 weeks treatment, all animals were anaesthetized and blood was collected for serum urea and creatinine levels assessment in plasma and kidney tissue were excised for evaluation of oxidative stress markers. Treatment with U. dioica significantly inhibited increase in serum urea and creatinine in plasma that were observed in diabetic mice. Furthermore, the elevated level of oxidative stress markers (glutathione oxidation, lipid peroxidation (LPO), protein carbonyl) in renal supernatant of diabetic mice was inhibited by U. dioica treatment. Interestingly, U. dioica promoted beneficial effects of PIO in reducing STZ-induced hyperglycemia, renal damage and oxidative stress markers. Our findings showed that PIO plus U. dioica have synergism protective effects against STZ-induced nephropathy that can be a candidate as a therapeutic approach in order to treatment of DN.

Manejo integrado de la plaga Tetranychus urticae (Acari: Tetranychidae) en cultivos de frutilla del Cinturón Hortícola Platense

OpenAIRE

Gugole Ottaviano, María Fernanda

2013-01-01

En el marco de la sustentabilidad de los sistemas agrícolas, el Manejo Integrado de Plagas propone utilizar todas las técnicas y métodos disponibles y compatibles entre sí, para mantener a la población de una plaga en niveles por debajo de aquellos que causan daño económico. Se basa en el análisis de la relación costo/beneficio, considerando los intereses e impactos sobre los productores, la sociedad y el ambiente. Este sistema de manejo tiene un enfoque ecológico y multidisciplinario que req...

The landsnail Cepaea nemoralis regulates internal Cd levels when fed on Cd-enriched stinging nettle (Urtica dioica) leaves at low, field-relevant concentrations

International Nuclear Information System (INIS)

Notten, M.J.M.; Oosthoek, A.J.P.; Rozema, J.; Aerts, R.

2006-01-01

We studied Cd accumulation in Cepaea nemoralis snails at low, but field-relevant Cd concentrations in the diet (Urtica dioica leaves). Six treatments of U. dioica plants were grown, resulting in leaf Cd concentrations between 0 and 2.6 μg g -1 dw. Seven snails per treatment were fed for 38 days. Leaf Cd concentrations did not affect food consumption rates, and consequently Cd intake rates increased with increasing leaf concentrations. No differences were detected among treatments in the final soft tissue Cd concentrations and body burdens in the snails. Regression analyses showed no positive relationship between either snail Cd concentrations or body burdens and total Cd intake. This suggests a regulation of internal Cd concentrations at low food Cd concentrations. Our data suggest that Cd excretion via the mucus plays a substantial role in this regulation, in addition to Cd excretion via the faeces. Snail shells were no sinks for Cd. - Cd excretion via the mucus plays a substantial role in the regulation of C. nemoralis soft tissue Cd concentrations at low, but field-relevant Cd concentrations in the food

The landsnail Cepaea nemoralis regulates internal Cd levels when fed on Cd-enriched stinging nettle (Urtica dioica) leaves at low, field-relevant concentrations

Energy Technology Data Exchange (ETDEWEB)

Notten, M.J.M. [Institute of Ecological Science, Department of Systems Ecology, Vrije Universiteit Amsterdam, De Boelelaan 1085, 1081 HV, Amsterdam (Netherlands)]. E-mail: martje.notten@ecology.falw.vu.nl; Oosthoek, A.J.P. [Institute of Ecological Science, Department of Systems Ecology, Vrije Universiteit Amsterdam, De Boelelaan 1085, 1081 HV, Amsterdam (Netherlands); Rozema, J. [Institute of Ecological Science, Department of Systems Ecology, Vrije Universiteit Amsterdam, De Boelelaan 1085, 1081 HV, Amsterdam (Netherlands); Aerts, R. [Institute of Ecological Science, Department of Systems Ecology, Vrije Universiteit Amsterdam, De Boelelaan 1085, 1081 HV, Amsterdam (Netherlands)

2006-01-15

We studied Cd accumulation in Cepaea nemoralis snails at low, but field-relevant Cd concentrations in the diet (Urtica dioica leaves). Six treatments of U. dioica plants were grown, resulting in leaf Cd concentrations between 0 and 2.6 {mu}g g{sup -1} dw. Seven snails per treatment were fed for 38 days. Leaf Cd concentrations did not affect food consumption rates, and consequently Cd intake rates increased with increasing leaf concentrations. No differences were detected among treatments in the final soft tissue Cd concentrations and body burdens in the snails. Regression analyses showed no positive relationship between either snail Cd concentrations or body burdens and total Cd intake. This suggests a regulation of internal Cd concentrations at low food Cd concentrations. Our data suggest that Cd excretion via the mucus plays a substantial role in this regulation, in addition to Cd excretion via the faeces. Snail shells were no sinks for Cd. - Cd excretion via the mucus plays a substantial role in the regulation of C. nemoralis soft tissue Cd concentrations at low, but field-relevant Cd concentrations in the food.

Mites fluctuation population on peach tree (Prunus persica (L. Batsch and in associated plants

Directory of Open Access Journals (Sweden)

Carla Rosana Eichelberger

2011-09-01

Full Text Available Despite the importance of peach (Prunus persica (L. Batsch in Rio Grande do Sul, little is known about mites fluctuation population considered important to this crop. The objective of this study was to know the population diversity and fluctuation of mite species associated with Premier and Eldorado varieties in Roca Sales and Venâncio Aires counties, Rio Grande do Sul. The study was conducted from July 2008 to June 2009 when 15 plants were randomly chosen in each area. The plants were divided in quadrants and from each one a branch was chosen from which three leaves were removed: one collected in the apical region, another in the medium and the other in the basal region, totalizing 180 leaves/area. Five of the most abundant associated plants were collected monthly in enough amounts for the screening under the stereoscopic microscope during an hour. A total of 1,124 mites were found belonging to 14 families and 28 species. Tetranychus ludeni Zacher, 1913, Panonychus ulmi (Koch, 1836 and Mononychellus planki (McGregor, 1950 were the most abundant phytophagous mites, whereas Typhlodromalus aripo Deleon, 1967 and Phytoseiulus macropilis (Banks, 1904 the most common predatory mites. The period of one hour under stereoscopic microscope was enough to get a representative sample. In both places evaluated the ecologic indices were low, but little higherin Premier (H' 0.56; EqJ: 0.43 when compared to Eldorado (H' 0.53; EqJ 0.40. In Premier constant species were not observed and accessory only Brevipalpus phoenicis (Geijskes, 1939, T. ludeni and T. aripo. Higher abundance was observed in December and January and bigger amount in April. Already in Eldorado, T. ludeni and P. ulmi were constants. Greater abundance was observed in November and December, whereas grater richness in December and January. In both orchards were not found mites in buds. Tetranychus ludeni is the most abundant phytophagous mites with outbreak population in November, December and

Protective effect of Urtica dioica L. on renal ischemia/reperfusion injury in rat.

Science.gov (United States)

Sayhan, Mustafa Burak; Kanter, Mehmet; Oguz, Serhat; Erboga, Mustafa

2012-12-01

Renal ischemia-reperfusion (I/R) injury may occur after renal transplantation, thoracoabdominal aortic surgery, and renal artery interventions. This study was designed to investigate the effect of Urtica dioica L. (UD), in I/R induced renal injury. A total of 32 male Sprague-Dawley rats were divided into four groups: control, UD alone, I/R and I/R + UD; each group contain 8 animals. A rat model of renal I/R injury was induced by 45-min occlusion of the bilateral renal pedicles and 24-h reperfusion. In the UD group, 3 days before I/R, UD (2 ml/kg/day intraperitoneal) was administered by gastric gavage. All animals were sacrificed at the end of reperfusion and kidney tissues samples were obtained for histopathological investigation in all groups. To date, no more histopathological changes on intestinal I/R injury in rats by UD treatment have been reported. Renal I/R caused severe histopathological injury including tubular damage, atrophy dilatation, loss of brush border and hydropic epithelial cell degenerations, renal corpuscle atrophy, glomerular shrinkage, markedly focal mononuclear cell infiltrations in the kidney. UD treatment significantly attenuated the severity of intestinal I/R injury and significantly lowered tubulointerstitial damage score than the I/R group. The number of PCNA and TUNEL positive cells in the control and UD alone groups was negligible. When kidney sections were PCNA and TUNEL stained, there was a clear increase in the number of positive cells in the I/R group rats in the renal cortical tissues. However, there is a significant reduction in the activity of PCNA and TUNEL in kidney tissue of renal injury induced by renal I/R with UD therapy. Our results suggest that administration of UD attenuates renal I/R injury. These results suggest that UD treatment has a protective effect against renal damage induced by renal I/R. This protective effect is possibly due to its ability to inhibit I/R induced renal damage, apoptosis and cell proliferation.

Enfermedad de marchitamiento fúngico en plántulas delechuga: un modelo didáctico-experimental para laenseñanza de los postulados de Koch

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Omar Robledo D\\u2019Angelo

2016-01-01

Full Text Available La enseñanza del método científico se ve facilitada mediante prácticas experimentales sencillas pero rigurosas. Los postulados de Koch representan un avance histórico en el desarrollo del método científico. Éstos constituyen una guía o protocolo a seguir para comprobar empíricamente que un determinado microorganismo es el agente causal de una patología infecciosa en un hospedero susceptible. En el presente trabajo se demuestra que la patología de marchitamiento fúngico (damping-off en plántulas de lechuga constituye un modelo didácticoexperimental para la enseñanza y la puesta en acción de dichos postulados. Fue posible la utilización de materiales de bajo costo con una metodología sencilla, reproducible y libre de riesgos para la salud humana, facilitando su aplicabilidad en cualquier centro de enseñanza secundaria o terciaria.

Molecular cloning and tissue-specific transcriptional regulation of the first peroxidase family member, Udp1, in stinging nettle (Urtica dioica).

Science.gov (United States)

Douroupi, Triantafyllia G; Papassideri, Issidora S; Stravopodis, Dimitrios J; Margaritis, Lukas H

2005-12-05

A full-length cDNA clone, designated Udp1, was isolated from Urtica dioica (stinging nettle), using a polymerase chain reaction based strategy. The putative Udp1 protein is characterized by a cleavable N-terminal signal sequence, likely responsible for the rough endoplasmic reticulum entry and a 310 amino acids mature protein, containing all the important residues, which are evolutionary conserved among different members of the plant peroxidase family. A unique structural feature of the Udp1 peroxidase is defined into the short carboxyl-terminal extension, which could be associated with the vacuolar targeting process. Udp1 peroxidase is differentially regulated at the transcriptional level and is specifically expressed in the roots. Interestingly, wounding and ultraviolet radiation stress cause an ectopic induction of the Udp1 gene expression in the aerial parts of the plant. A genomic DNA fragment encoding the Udp1 peroxidase was also cloned and fully sequenced, revealing a structural organization of three exons and two introns. The phylogenetic relationships of the Udp1 protein to the Arabidopsis thaliana peroxidase family members were also examined and, in combination with the homology modelling approach, dictated the presence of distinct structural elements, which could be specifically involved in the determination of substrate recognition and subcellular localization of the Udp1 peroxidase.

Structure and expression of sulfatase and sulfatase modifying factor genes in the diamondback moth, Plutella xylostella.

Science.gov (United States)

Ma, Xiao-Li; He, Wei-Yi; Chen, Wei; Xu, Xue-Jiao; Qi, Wei-Ping; Zou, Ming-Min; You, Yan-Chun; Baxter, Simon W; Wang, Ping; You, Min-Sheng

2017-06-01

The diamondback moth, Plutella xylostella (L.), uses sulfatases (SULF) to counteract the glucosinolate-myrosinase defensive system that cruciferous plants have evolved to deter insect feeding. Sulfatase activity is regulated by post-translational modification of a cysteine residue by sulfatase modifying factor 1 (SUMF1). We identified 12 SULF genes (PxylSulfs) and two SUMF1 genes (PxylSumf1s) in the P. xylostella genome. Phylogenetic analysis of SULFs and SUMFs from P. xylostella, Bombyx mori, Manduca sexta, Heliconius melpomene, Danaus plexippus, Drosophila melanogaster, Tetranychus urticae and Homo sapiens showed that the SULFs were clustered into five groups, and the SUMFs could be divided into two groups. Profiling of the expression of PxylSulfs and PxylSumfs by RNA-seq and by quantitative real-time polymerase chain reaction showed that two glucosinolate sulfatase genes (GSS), PxylSulf2 and PxylSulf3, were primarily expressed in the midgut of 3rd- and 4th-instar larvae. Moreover, expression of sulfatases PxylSulf2, PxylSulf3 and PxylSulf4 were correlated with expression of the sulfatases modifying factor PxylSumf1a. The findings from this study provide new insights into the structure and expression of SUMF1 and PxylSulf genes that are considered to be key factors for the evolutionary success of P. xylostella as a specialist herbivore of cruciferous plants. © 2017 Institute of Zoology, Chinese Academy of Sciences.

Population dynamics of interacting predatory mites, Phytoseiulus persimilis and Neoseiulus californicus, held on detached bean leaves.

Science.gov (United States)

Walzer, A; Blümel, S; Schausberger, P

2001-01-01

The success of combined release of the predatory mites Phytoseiulus persimilis and Neoseiulus californicus in suppression of spider mites may be related to the effects of the interactions between the two predators on their population dynamics. We studied population growth and persistence of the specialist P persimilis and the generalist N. californicus reared singly versus reared in combination after simultaneous and successive predator introductions on detached bean leaf arenas with abundant prey, Tetranychus urticae. and with diminishing prey. When reared singly with abundant prey, either predator population persisted at high densities to the end of the experiment. In every predator combination system with abundant prey and various initial predator:predator ratios N. californicus displaced P persimilis. When held singly with diminishing prey, the population of P. persimilis grew initially faster than the population of N. californicus but both species reached similar population peaks. Irrespective whether reared singly or in combination. N. californicus persisted three to five times longer after prey depletion than did P. persimilis. Regarding the crucial interactions in the predator combination systems, we conclude that intraguild predation was a stronger force than food competition and finally resulted in the displacement of P. persimilis. Previous studies showed that intraguild predation between the specialist P. persimilis and the generalist N. californicus is strongly asymmetric favoring the generalist. We discuss the implications of potential interactions between P. persimilis and N. californicus to biological control of spider mites.

Prey and Non-prey Arthropods Sharing a Host Plant: Effects on Induced Volatile Emission and Predator Attraction

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Hordijk, Cornelis A.; Posthumus, Maarten A.; Dicke, Marcel

2008-01-01

It is well established that plants infested with a single herbivore species can attract specific natural enemies through the emission of herbivore-induced volatiles. However, it is less clear what happens when plants are simultaneously attacked by more than one species. We analyzed volatile emissions of lima bean and cucumber plants upon multi-species herbivory by spider mites (Tetranychus urticae) and caterpillars (Spodoptera exigua) in comparison to single-species herbivory. Upon herbivory by single or multiple species, lima bean and cucumber plants emitted volatile blends that comprised mostly the same compounds. To detect additive, synergistic, or antagonistic effects, we compared the multi-species herbivory volatile blend with the sum of the volatile blends induced by each of the herbivore species feeding alone. In lima bean, the majority of compounds were more strongly induced by multi-species herbivory than expected based on the sum of volatile emissions by each of the herbivores separately, potentially caused by synergistic effects. In contrast, in cucumber, two compounds were suppressed by multi-species herbivory, suggesting the potential for antagonistic effects. We also studied the behavioral responses of the predatory mite Phytoseiulus persimilis, a specialized natural enemy of spider mites. Olfactometer experiments showed that P. persimilis preferred volatiles induced by multi-species herbivory to volatiles induced by S. exigua alone or by prey mites alone. We conclude that both lima bean and cucumber plants effectively attract predatory mites upon multi-species herbivory, but the underlying mechanisms appear different between these species. PMID:18185960

Complex Odor from Plants under Attack: Herbivore's Enemies React to the Whole, Not Its Parts

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van Wijk, Michiel; de Bruijn, Paulien J. A.; Sabelis, Maurice W.

2011-01-01

Background Insect herbivory induces plant odors that attract herbivores' natural enemies. Assuming this attraction emerges from individual compounds, genetic control over odor emission of crops may provide a rationale for manipulating the distribution of predators used for pest control. However, studies on odor perception in vertebrates and invertebrates suggest that olfactory information processing of mixtures results in odor percepts that are a synthetic whole and not a set of components that could function as recognizable individual attractants. Here, we ask if predators respond to herbivore-induced attractants in odor mixtures or to odor mixture as a whole. Methodology/Principal Findings We studied a system consisting of Lima bean, the herbivorous mite Tetranychus urticae and the predatory mite Phytoseiulus persimilis. We found that four herbivore-induced bean volatiles are not attractive in pure form while a fifth, methyl salicylate (MeSA), is. Several reduced mixtures deficient in one component compared to the full spider-mite induced blend were not attractive despite the presence of MeSA indicating that the predators cannot detect this component in these odor mixtures. A mixture of all five HIPV is most attractive, when offered together with the non-induced odor of Lima bean. Odors that elicit no response in their pure form were essential components of the attractive mixture. Conclusions/Significance We conclude that the predatory mites perceive odors as a synthetic whole and that the hypothesis that predatory mites recognize attractive HIPV in odor mixtures is unsupported. PMID:21765908