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Population dynamic of guava psyllid Triozoida limbata (Hemiptera: Psyllidae) in Londrina Parana, Brazil/ Flutua o populacional do psilídeo-da-goiabeira, Triozoida limbata (Hemiptera: Psyllidae) na regi o de Londrina, Pr  [cached]
Fernanda Maura Sassiotti Dalberto,Ayres de O. Menezes Junior,Homero Christoval Sim?es,Norton Polo Benito
Semina : Ciências Agrárias , 2004,
Abstract: The Psyllidae are sap-suckers insects, highly host and food specific, found mainly in sprouts, and are considered important guava pests. Large populations of these insects can be hazardous, since they cause plant weakness by the toxic action of the saliva injected during their feeding process. The objective of this work was to verify the population fluctuation of the psyllidae Trizoida limbata in guava trees in Londrina, Paraná, Brazil. The monitoring of an adult T.limbata population was carried out in areas of wild guava trees, using 10 yellow adhesive traps, 30 m far from each other. Collection took place monthly from March 2002 to May 2003. T.limbata populations were found during every month of the year, reaching their peak in October. Average and maximum temperatures showed a significant correlation with the psyllidae population fluctuation, affecting it positively. Heavy rain periods and low temperatures were not restricting, but they caused a reduction in population Os psilídeos s o insetos sugadores de seiva, muito específicos com rela o ao hospedeiro e alimenta o, ocorrendo principalmente em brota es, sendo considerados uma importante praga de goiabeira. Altas popula es podem tornar-se nocivas, pois provocam depauperamento das plantas pela a o tóxica da saliva injetada durante sua alimenta o. O objetivo deste trabalho foi conhecer a flutua o populacional do psilídeo Triozoida limbata em goiabeiras na regi o de Londrina, Paraná. Em áreas de ocorrência natural de plantas de goiaba foi realizado o monitoramento da popula o de adultos utilizando-se 10 armadilhas adesivas amarelas, colocadas uma por planta, distanciadas cerca de 30 metros entre si. As coletas foram realizadas mensalmente de mar o de 2002 a maio de 2003. Popula es de T. limbata ocorreram durante todos os meses do ano, com pico em outubro. Temperaturas médias e máximas apresentaram correla o significativa com a popula o do psilídeos, afetando-a positivamente. Períodos com alta pluviosidade ou baixas temperaturas n o foram limitantes, mas causaram redu o na popula o.
Dinamica populacional e evolu??o de dano de Triozoida limbata (Hemiptera: Psillydae) em goiabeira, em Jaboticabal, SP
Colombi, Carlos Alexandre;Galli, Júlio César;
Ciência e Agrotecnologia , 2009, DOI: 10.1590/S1413-70542009000200008
Abstract: the present work aimed at learning the population dynamic of triozoida limbata (enderlein, 1918) (hemiptera: psyllidae) in a guava orchard submitted to the minimum use of insecticide in jaboticabal - sp. for the study of population fluctuation and the evolution of damage from the psillid we analyzed 20 plants of the orchard biweekly, during the period from march 2005 to june 2006. for each plant we evaluated 10 leaves containing the symptom of the attack from the psillid. the evaluated parameters were the number of nymphs and the percentage of damage caused in the leaves, in accordance with a scale of notes. these parameters were analyzed in histograms and correlated to the meteorological factors. the population density of the psillid increased considerably with the approach of the spring and presented a positive correlation with the temperature. the level of damage of the psillid accompanied the population density of the pest. according to the data found in this work we may conclude that the increase of the temperature causes an increase in the population density of t. limbata and the largest population densities from psillid occur in the months of september to november and the smallest densities occur between the months of may and july.
Redu??o de aplica??es de inseticidas através da ado??o de táticas de manejo integrado do Triozoida limbata (Enderlein, 1918) (Hemiptera: triozidae) em goiabeira
Pazini, Wilson Carlos;Galli, Júlio Cesar;
Revista Brasileira de Fruticultura , 2011, DOI: 10.1590/S0100-29452011000100010
Abstract: the guava tree pest that has been requesting larger control frequency, in the area of jaboticabal - s?o paulo in the last years, is the psilídeo triozoida limbata. thus, the objectives of this research were: a) compare control tactics t. limbata based on monitoring and selectivity of insecticide to decrease the applications; b) to register and to correlate the natural enemies in habitants in guava tree ecosystem with the key pest and with meteorological factors; c) see if the control of t. limbata affects the population of fruit flies and d) to verify the efficiency of appropriate insecticides to imp, in control of t. limbata. the experiment was conducted in 2004, in an orchard of paluma cultivar in vista alegre do alto, sp. the used strategies were (doses in g.a.i./100l water): control; imidacloprid + beta-cyfluthrin (2.5 + 0.3); acetamiprid (4.0); fenpropathrin (15.0) and regional conventional treatment. it was concluding that is possible to reduce the number of applications of less aggressive insecticides to the environment and the man, with the adoption of monitoring of t. limbata and implementing the action level. the natural enemies' populations densities (scymnus spp., cycloneda sanguinea, azia luteipes, crysoperla spp., polybia spp., brachygastra ssp.) present positive correlations with the populations of t. limbata. population fluctuations of t. limbata and natural enemies are not altered by meteorological factors (precipitation and temperature) in irrigated orchard. the population of anastrepha spp. is minimized when of the applications is for control t. limbata. the insecticides imidacloprid, imidacloprid + beta-cyfluthrin, acetamiprid and fenpropathrin are efficient in the control of t. limbata.
Residual dynamics of thiacloprid in medical herbs marjoram, thyme, and camomile and in soil
Residual dynamics of thiacloprid in medical herbs marjoram, thyme, and camomile in soil

YU Yun-long,WU Jia-lun,STAHLER Matthias,PESTEMER Wilfried,
YU Yun-long
,WU Jia-lun,STAHLER Matthias,PESTEMER Wilfried

环境科学学报(英文版) , 2007,
Abstract: Thiacloprid is a new insecticide of the chloronicotinyl family. To assess its risk after application, residual characteristics of thiacloprid in marjoram, thyme, and camomile and in soil were studied under field conditions. The active ingredient was extracted from the plant material using a mixture of acetone-water. After filtration, the extract was concentrated to the aqueous phase, diluted with water, and portioned against ethyl acetate on a matrix solid phase dispersion column. Thiacloprid was extracted from soil using a mixture of methanol-water, filtered, and reextracted (clean up) with dichloromethane. The residues were quantified using HPLC-MS-MS. The methods were validated by recovery experiments. Thiacloprid residues in marjoram, thyme, and camomile and in soil persisted beyond 10, 14, 14, and 21 d but no residues were detected after 14, 21, 21, and 28 d, respectively. The data obtained in this study indicated that the biexponential model is more suitable than the first-order function to describe the decline of thiacloprid in fresh marjoram, fresh thyme, and dried camomile flowers with half-life (t1/2) of 1.1, 0.7, and 1.2 d, respectively. However, both the first-order function and biexponential model were found to be applicable for dissipation of thiacloprid in soil with almost the same t1/2 values of 3.5 and 3.6 d.The results indicated that thiacloprid dissipates rapidly and does not accumulate in the tested herbs and in soil.
A new name for the Neotropical genus Aniarella Enderlein (Diptera, Sciaridae)
?zdikmen, Hüseyin;Ba?ar, Kadir;
Revista Brasileira de Entomologia , 2011, DOI: 10.1590/S0085-56262011000100003
Abstract: a new name for the neotropical genus aniarella enderlein (diptera, sciaridae). a junior homonym was detected among neotropical sciarid flies genera and the following replacement name is proposed: novaniarella nom. nov. for aniarella enderlein, 1911 (nec bolivar, 1906). accordingly, new combinations are herein proposed for the species currently included in this genus: novaniarella azteca (lane, 1959) comb. nov., novaniarella brevis (rubsaamen, 1894) comb. nov. and novaniarella pelluscens (enderlein, 1911) comb. nov.
José Pinochet-Roco,Irma Northland-Leppe,Juana Capetillo-Arcos,Pedro Jara-Seguel
Gayana (Concepción) , 2008,
Abstract: Fissurella limbata (Sowerby, 1835), presenta un número cromosómico diploide 2n = 32 similar al descrito previamente para otras especies del género Fissurella Reeve 1849. El juego cromosómico haploide deF limbata tiene siete cromosomas metacéntricos, seis submetacéntricos y tres subtelocéntricos. Los cromosomas son peque os y no exceden de 4,0 mm en longitud.
Investigation of the mechanism of binding of thiacloprid to human serum albumin using spectroscopic techniques and molecular modeling methods  [PDF]
Chuanxian Wang,Qinghua Chu,Changyun Chen,Zhao Bo
Spectroscopy: An International Journal , 2011, DOI: 10.3233/spe-2011-0498
Abstract: Fluorescence spectroscopy, UV absorption, circular dichroism (CD) spectroscopy and molecular modeling methods were used to characterize the binding properties of thiacloprid (TL) with human serum albumin (HSA) at molecular level under physiological conditions. The fluorescence intensity of HSA decreased regularly with the gradually increasing concentration of thiacloprid. The binding constant K at three different temperatures (290, 300 and 310 K) were 3.07, 2.74 and 1.35 × 104 M−1, respectively, for TL–HSA interaction have been calculated from the relevant fluorescence data. CD spectroscopic measurements have shown that the secondary structures of the protein have been changed by the interaction of thiacloprid with HSA. Furthermore, the study of molecular modeling indicated that thiacloprid could be located on the surface of the binding pocket of subdomains IIA in HSA. The hydrophobic interaction was the major acting force and there are H-bonds and electrostatic interactions between TL and HSA, which is in good agreement with the results from the experimental thermodynamic parameters (the enthalpy change ΔH0 and the entropy change ΔS0 were calculated to be ?20.378 kJ/mol and 16.328 J/mol K according to the Van9t Hoff equation).
Interaction of thiacloprid with bovine hemoglobin using spectroscopic and molecular modeling methods  [PDF]
Chang-Yun Chen,Bo Zhao,Zheng-Wu Wang
Spectroscopy: An International Journal , 2010, DOI: 10.3233/spe-2010-0477
Abstract: The interaction of thiacloprid (TL) to bovine hemoglobin (BHb) under physiological conditions was investigated by using fluorescence spectroscopy, circular dichroism spectroscopy (CD) and molecular modeling. The fluorescence intensity of BHb decreased regularly with the gradual increasing concentration of TL. It is observed that there was a prominent interaction between TL and BHb. The binding constants KA at 288, 298 and 308 K obtained are 8.04, 5.26 and 3.08×104 l?·?mol–1, respectively. The standard enthalpy change (ΔH°) and the standard entropy change (ΔS°) are calculated to be –34.54 KJ?·?mol–1 and –25.77 J?·?mol–1?·?K–1, which indicated that hydrogen bonding forces play major role in the interaction between TL and BHb. The alternations of protein secondary structure in the presence of TL were determined by CD spectroscopy. The results revealed that the content of α-helix was decreased from 51.85% in free BHb to 48.14% in TL–BHb complex. Molecular modeling study and our experimental results both showed that the binding mode of TL–BHb complex could be attributed to hydrogen bonding and hydrophobic interaction.
Chemical composition of the essential oil of Salvia limbata C. A. Mey
Seyed Ebrahim Sajjadi,Zahra Shahpiri
DARU : Journal of Pharmaceutical Sciences , 2004,
Abstract: The essential oil obtained by hydrodistillation of the aerial parts of Salvia limbata C.A. Mey. (Lamiaceae) was analyzed by GC/MS. Among the forty-two constituent, forty components were characterized representing 98.6% of the total component which were detected. Bicyclogermacrene (21.1%), α-pinene (15.5%), 1,8-cineole (11.0%), sabinene (10.6%), β-pinene (9.2%), spathulenol (8.2%), β-caryophyllene (5.3%) and δ-elemene (5.1%) were found to be the major constituents.
Pinochet-Roco,José; Northland-Leppe,Irma; Capetillo-Arcos,Juana; Jara-Seguel,Pedro;
Gayana (Concepción) , 2008, DOI: 10.4067/S0717-65382008000200015
Abstract: fissurella limbata (sowerby, 1835), presenta un número cromosómico diploide 2n = 32 similar al descrito previamente para otras especies del género fissurella reeve 1849. el juego cromosómico haploide def limbata tiene siete cromosomas metacéntricos, seis submetacéntricos y tres subtelocéntricos. los cromosomas son peque?os y no exceden de 4,0 mm en longitud.
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