Automação de balanças comerciais como lisímetros em ambiente protegido.

bitstream/CNPDIA-2009-09/11843/1/CT80_2006.pd

Three-year observations of halocarbons at the Nepal Climate Observatory at Pyramid (NCO-P, 5079 m a.s.l.) on the Himalayan range

A monitoring programme for halogenated climate-altering gases has been established in the frame of the SHARE EV-K<sup>2</sup>-CNR project at the Nepal Climate Laboratory – Pyramid in the Himalayan range at the altitude of 5079 m a.s.l. The site is very well located to provide important insights on changes in atmospheric composition in a region that is of great significance for emissions of both anthropogenic and biogenic halogenated compounds. Measurements are performed since March 2006, with grab samples collected on a weekly basis. The first three years of data have been analysed. After the identification of the atmospheric background values for fourteen halocarbons, the frequency of occurrence of pollution events have been compared with the same kind of analysis for data collected at other global background stations. The analysis showed the fully halogenated species, whose production and consumption are regulated under the Montreal Protocol, show a significant occurrence of "above the baseline" values, as a consequence of their current use in the developing countries surrounding the region, meanwhile the hydrogenated gases, more recently introduced into the market, show less frequent spikes. <br><br> Atmospheric concentration trends have been calculated as well, and they showed a fast increase, ranging from 5.7 to 12.6%, of all the hydrogenated species, and a clear decrease of methyl chloroform (−17.7%). The comparison with time series from other stations has also allowed to derive Meridional gradients, which are absent for long living well mixed species, while for the more reactive species, the gradient increases inversely with respect to their atmospheric lifetime. The effect of long range transport and of local events on the atmospheric composition at the station has been analysed as well, allowing the identification of relevant source regions the Northern half of the Indian sub-continent. Also, at finer spatial scales, a smaller, local contribution of forest fires from the Khumbu valley has been detected

Avaliação de linhagens, materiais comerciais e duas populações de milho para tolerância a alumínio.

Neste trabalho realizou-se a avaliacao da tolerancia a Al (4,5 mg.l) de 39 linhagens, 98 materiais comerciais, 167 progenies de uma populacao IAC-Maya e de 466 progenies de uma populacao IAC-Genetica, usando-se a tecnica de solucao nutritiva. Foram usadas na avaliacao as características ICR (indice de crescimento da radicula = comprimento relativo da radicula -CRR (CR+Al.CR-Al)- multiplicado por comprimento relativo da raiz secundaria mais longa - CRRSML (CRSML+Al/CRSML-Al) e CLR (comprimento liquido da radicula = diferenca entre os valores de comprimento da radicula - CR - obtidos no inicio e fim do periodo de crescimento das plantas em presenca de Al). As linhagens e as progenies da populacao IAC-Maya a de milho foram avaliadas através do ICR enquanto que os materiais comerciais e as progenies da populacao IAC-Genetica foram avaliados pelos valores de CLR. Os controles utilizados foram IAC HS1227 (tolerante a Al) e IAC HS7777 (sensivel a Al). O metodo de solucao nutritiva foi eficiente na diferenciacao da tolerancia a Al dentre os materiais testados, evidenciando a ocorrencia de ampla variabilidade genetica para essa caracteristica. As seguintes linhagens e materiais comerciais apresentaram tolerancia a Al (4,5 mg/l): Porto Rico 70. D,2, IP 38-5-3, IP 365-4-I, IA 2992-3-1-2-3, Vic 3-2-3-30-V-6, 490, 519, 532, 536-2 e 820 (linhagens) e AG 82, AG 260, AGROMEM 1022, ASGROW 1255, DINA 03S, DINA 47, IAC Hmd 7974, SS 1243 e UNICAMP 720 (materiais comerciais)

Determination of pesticide residues in tomato using dispersive solid-phase extraction and gas chromatography/ion trap mass spectrometry

Tomato crop is frequently damaged by diseases, pests and abiotic stresses, resulting in lower yielding and loss of fruit quality. The intensive use of pesticides in tomatoes without observation of good agriculture practices and regulations has caused great concern with a probable final product contamination. The QuEChERS method of sample preparation was used for the determination of six pesticides (buprofezin, carbofuran, endosulfan-α, endosulfan-β, endosulfan sulfate and monocrotophos) in thirty three tomato samples collected from local market retailers. The method involved extraction with acetonitrile, liquid-liquid partition with addition of MgSO4 and NaCl followed by dispersive solid phase extraction using primary secondary amine sorbent and the analyses were carried out with a gas chromatography/mass spectrometry equipment by ion trap. Recovery studies for different pesticides ranged from 71 to 111% and the relative standard deviation (RSD) was below 15%. No pesticide residue was detected (> LOD) among the thirty three tomato samples analysed.A cultura do tomate é frequentemente afetada por pragas, doenças e estresses abióticos, resultando em menor produtividade e perda de qualidade dos frutos. O uso intensivo de pesticidas em tomates sem utilização das boas práticas agrícolas tem causado grande preocupação quanto à provável contaminação do produto final. O método QuEChERS foi utilizado para a determinação de seis pesticidas (buprofezina, carbofurano, α-endosulfan, β-endosulfan, sulfato de endosulfan e monocrotofós) em amostras de tomate coletadas em supermercados. O método envolveu a extração líquido-líquido com acetonitrila, adição de MgSO4 e NaCl seguida de extração em fase sólida dispersiva com PSA (amina primária secundária) e as análises foram realizadas com cromatografia gasosa/espectrometria de massa ion trap. O estudo de recuperação para os pesticidas variou de 71 a 111% e o desvio padrão relativo foi inferior a 15%. Não foram detectados resíduos de pesticidas (> LOD) nas trinta e três amostras de tomate analisadas.(FAPESP) São Paulo Research Foundatio