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In the Metropolitan Region of Campinas (MRC), Brazil, high levels of primary pollutants contribute to ozone (O3) formation. However, little is known regarding the O3 effects in the tropics. Objectives in this study were to characterize the present levels of O3 pollution and to evaluate the relevance of current concentration-based indices for assessing the phytotoxic potential of O3. Changes in O3 concentrations and precursors at 5 monitoring stations within towns of MRC were analyzed. The daily O3 profile was typical for urban sites and showed little yearly variation. Given the permanently foliated forest canopy, yearly rather than seasonal O3 indices were thus more appropriate for estimating the effective ozone dose. With yearly SUM00, SUM60 and AOT40 of 156, 16 and 14 ppm h and confirmed by evidence of O3 injury in foliage, oxidative stress in the MRC has reached levels high enough to affect trees from the Atlantic Semi-deciduous Forest.

Brazilian soybean cultivars (Glycine max Sambaíba and Tracajá) routinely grown in Amazonian areas were exposed to filtered air (FA) and filtered air enriched with ozone (40 and 80 ppb, 6 h/day for 5 days) to assess their level of tolerance to this pollutant by measuring changes in key biochemical, physiological, and morphological indicators of injury and in enzymatic and non-enzymatic antioxidants. Sambaíba plants were more sensitive to ozone than Tracajá plants, as revealed by comparing indicator injury responses and antioxidant stimulations. Sambaíba exhibited higher visible leaf injury, higher stomatal conductance, and a severe decrease in the carbon assimilation rate. Higher ozone level (80 ppb) caused an increase in cell death in both cultivars. Levels of malondialdehyde and hydrogen peroxide also increased in Tracajá exposed under 80 ppb. Sambaíba plants exhibited decreases in ascorbate and glutathione levels and in enzymatic activities associated with these antioxidants. The higher tolerance of the Tracajá soybean appeared to be indicated by reduced physiological injuries and lower stomatal conductance, which might decrease the influx of ozone and enhance oxidation-reduction reactions involving catalase, ascorbate peroxidase, ascorbate, and glutathione, most likely stimulated by higher hydrogen peroxide.

We investigated whether the fructan content, a storage carbohydrate, of Lolium multiflorum ‘Lema’ plants grown in a subtropical urban environment characterized by typical diurnal profiles of air pollutants and meteorological conditions changed over the course of a day during different seasons. Plants were collected every 2 h on the last day of each two-month seasonal field experiment and separated into shoot (stubble or stubble+leaf blades) and roots for carbohydrate analyses and biomass determination. Diurnal contents of total fructose in the stubbles increased with high temperatures. In the roots, fructose accumulation showed a positive relation with hourly variations of both temperature and particulate matter and a negative relation with irradiance and SO2. Seasonal variation in shoot and root biomasses coincided with the seasonal variation of total fructose and were negatively affected by relative humidity and SO2, respectively. We concluded that hourly changes of fructans over the course of a day may increase the ability of L. multiflorum to tolerate short-term oscillations in weather and air pollution commonly observed in the subtropical urban environment, increasing its efficiency in monitoring air quality.

The wide use of the herbicide diuron has compromised surrounding uncultivated areas, resulting in acute and/or chronic damage to non-target plants. Thus, the aim of this research was to evaluate physiological and morphoanatomical responses in Bauhinia variegata L. plants to different doses of diuron. Seedlings of 90-day-old B. variegata were transplanted into 10liter pots. After an acclimation period (about 30 days), treatments consisting of different diuron doses were applied: 0 (control), 400, 800, 1600, and 2400g ai ha-1. The experiment was conducted in a randomized block design in a 5×5 factorial scheme with five doses of diuron five evaluation times, and five replicates per treatment. Anatomical and physiological injuries were observed in leaves of Bauhina variegata 10h after diuron application. Disruption of waxes was observed on both sides of the leaves of plants exposed since the lowest dose. Plasmolysis in cells were observed in treated leaves; more severe damage was observed in plants exposed to higher doses, resulting in rupture of epidermis. The diuron herbicide also caused gradual reduction in the gas exchange and chlorophyll fluorescence variables. Among the morphoanatomical and physiological variables analyzed, the non-invasive ones (e.g., ETR, YII, and Fv/Fm) may be used as biomarkers of diuron action in association with visible symptoms. In addition, changes in leaf blade waxes and chlorophyll parenchyma damage may also be considered additional leaf biomarkers of diuron herbicide action.

The aim of this study was to evaluate the growth and development of Aechmea blanchetiana Baker L.B. Sm. in vitro on medium with 0.0, 0.145, 1.45 and 14.5 μM Cu and 0.0, 2.75, 27.5 and 275 μM Zn. Significant accumulation of Cu and Zn occurred at 14.5 μM Cu and 27.5 and 275 μM Zn, respectively, and there were no significant changes in contents of the other macro- and micronutrients. Superoxide dismutase (SOD) activity significantly changed in the presence of both metals. Spermine content increased as Zn concentration increased and decreased with increasing concentrations of Cu. There was an accumulation of H2O2 in the leaf tissue of plants grown in 1.45 and 14.5 μM Cu and 27.5 and 275 μM Zn. A. blanchetiana was found tolerant to the Cu and Zn in concentrations used in this study and displays the capacity to accumulate these metals.

The occurrence of visible leaf injury caused by ozone in Ipomoea nil 'Scarlet O'Hara' may be regulated by their redox state, affecting its bioindicator efficiency. Thus, this study aimed to determine whether the redox state of I. nil plants in a subtropical area (São Paulo, SE-Brazil) contaminated by ozone oscillates, and to identify the environmental factors behind these variations. We comparatively evaluated indicators of redox state (ascorbic acid, glutathione, superoxide dismutase, ascorbate peroxidase, glutathione reductase) and leaf injury during nine field experiments of 28 days each. The variations in the redox indicators were explained by the combined effects of chronic levels of ozone and meteorological variables (mainly global solar radiation and air temperature) 3-6 days prior to the sampling days. The ascorbic acid and glutathione were crucial for increasing plant tolerance to ozone. Weak visible injury was observed in all experiments and occurred in leaves with low levels of ascorbic and dehydroascorbic acids.

This study intended to determine whether the redox state in plants of Nicotiana tabacum ‘Bel-W3’ fluctuates in response to the environmental factors in a sub-tropical area contaminated by ozone (Sao Paulo, SE – Brazil) and which environmental factors are related to this fluctuation, discussing their biomonitoring efficiency. We comparatively evaluated the indicators of redox state (ascorbic acid, glutathione, superoxide dismutase, ascorbate peroxidase, and glutathione reductase) and leaf injury in 17 field experiments performed in 2008. The redox state was explained by the combined effects of chronic levels of O3 and meteorological variables 4–6 days prior to the plant sampling. Moderate leaf injury was observed in most cases. The redox state of tobacco decreases few days after their placement in the sub-tropical environment, causing them to become susceptible to oxidative stress imposed by chronic doses of O3. Its bioindicator efficiency would not be diminished in such levels of atmospheric contamination.

We intended to establish how efficient the leaf antioxidant responses of C. echinata are against oxidative environmental conditions observed in an urban environment and their relations to growth and biomass parameters. Plants were grown for 15 months in four sites: Congonhas and Pinheiros, affected by pollutants from vehicular emissions; Ibirapuera, affected by high O3 concentrations; and a greenhouse with filtered air. Fifteen plants were quarterly removed from each site for analysis of antioxidants, growth and biomass. Plants growing in polluted sites showed alterations in their antioxidants. They were shorter, had thicker stems and produced less leaf biomass than plants maintained under filtered air. The fluctuations in the levels of antioxidants were significantly influenced by combined effects of climatic and pollution variables. The higher were the antioxidant responses and the concentrations of pollutant markers of air contamination in each site the slower were the growth and biomass production.

The aims of this study were to investigate the sensitivity of Tradescantia pallida ‘Purpurea’ to genotoxicity induced by ozone, by means of the micronucleus (MCN) bioassay, to verify whether the intensity of genotoxic responses in inflorescences is modulated by concentrations of ascorbic acid (AA) in their bracts, and/or by air temperature variations during the progress of the bioassay, and to define the time lag necessary after ozone exposure to observe maximal genotoxic effects. Flowering branches were exposed to filtered air (control) and to 60 ppb of ozone (ozone) for 3 h in fumigation chambers during spring, autumn, winter and summer. After exposure, they were maintained for 24–120 h under filtered air for recovery. A sub-group of each treatment was taken every 24 h, when MCN was scored in inflorescences and the levels of AA were determined in bracts. Ozone caused a significant increase in the frequency of MCN after 24–120 of recovery, compared to measurements in inflorescences from the control treatment, but maximal MCN rate was reached between 72 and 120 h of recovery. The highest percentages of MCN in both fumigation treatments were found during the winter experiment. Ozone exposure did not induce significant changes in the content of AA. However, it was positively influenced by daily amplitude of air temperature during the period of the bioassay. The intensity of genotoxic damage and the time lag necessary to visualize an enhanced number of MCN depended on the levels of ascorbic acid in bracts 24 h before MCN scoring and on the daily amplitude of air temperature during the development of the bioassay. Narrower ranges between daily maximum and minimum temperatures (around 4 °C) during the days of experiment seemed to promote a more efficient diagnostic of genotoxiciy induced by ozone.

Previous studies have reported that the extent of leaf injury in Nicotiana tabacum “Bel-W3” exposed to environmental conditions in the city of Sao Paulo is influenced by weather conditions. This influence may occur by means of antioxidant responses. Thus, this study aimed to evaluate whether daily antioxidant responses to environmental variations interfere on the progression of leaf injury on plants of this cultivar during their exposure in a state park of Sao Paulo and to determine a linear combination of variables, among antioxidants and environmental factors, which mostly explain this visible response. Plants were exposed at the mentioned site for 14 days in four different experiments. During each experiment, three plants were daily sampled to determine the accumulated percentage of leaf area affected by necrosis and antioxidant responses (concentrations of total ascorbic acid (AA) and activity of superoxide dismutase (SOD) and peroxidases (POD)). Ozone concentrations and weather conditions were also daily measured. Pearson correlations and multivariate analyses assessed the relationship between biological and environmental variables. Leaf injury appeared between the 3rd and 6th days of exposure and increased over the exposure periods. The daily concentrations of AA tended to decrease with time of exposure in all experiments, but the activity of SOD and POD oscillated during plant exposure. Positive correlations were observed between AA or SOD and O3 concentrations, as well as negative correlations between AA and air temperature. The increasing percentage of leaf necrosis across the whole period was explained by decreasing levels of AA 2 days before injury estimation and by higher O3 concentrations 5 days before (R2 = 0.36; p

This study analyzed the relationship between environmental factors, especially air pollution and climatic conditions, and non-structural carbohydrates (NSC) in plants of Lolium multiflorum exposed during 10 consecutive periods of 28 days at a polluted site (Congonhas) and at a reference site in São Paulo city (Brazil). After exposure, NSC composition and leaf concentrations of Al, Fe, Cu, Zn, Pb and Cd were measured. The seasonal pattern of NSC accumulation was quite similar in both sites, but plants at Congonhas showed higher concentrations of these compounds, especially fructans of low and medium degree of polymerization. Regression analysis showed that NSC in plants growing at the polluted site were explained by variations on temperature and leaf concentration of Fe (positive effect), as well as relative humidity and particulate material (negative effect). NSC in the standardized grass culture, in addition to heavy metal accumulation, may indicate stressing conditions in a sub-tropical polluted environment.

A sensibilidade de Abelmoschus esculentus ao ozônio (O3) foi determinada em plantas expostas por quatro dias, seis horas/dia, ao ar filtrado (AF) e ao AF enriquecido com 80 ppb de O3 (AF+O3), em câmaras de fumigação, analisando-se sintomas foliares visíveis e alterações nas trocas gasosas e em antioxidantes. Avaliaram-se os sintomas foliares diariamente e as trocas gasosas e antioxidantes (ácido ascórbico e superóxido dismutase) ao fim do experimento. Todas as plantas em AF+O3 apresentaram sintomas foliares, caracterizados por pontuações avermelhadas na superfície adaxial, entre as nervuras. Em média, o índice de injúria foliar foi de 15% e a severidade de 62%. Fotossíntese líquida, condutância estomática, transpiração, concentração de ácido ascórbico e atividade da superóxido dismutase foram reduzidas significativamente nestas plantas, em comparação com as mantidas sob ar filtrado. Os resultados sugerem que Abelmoschus esculentus é sensível ao O3, apresentando baixos níveis de defesas antioxidativas e distúrbios fisiológicos. ABSTRACT - The sensitivity of Abelmoschus esculentus to ozone (O3) was assessed in plants exposed during four days, six hours/day, to filtered air (AF) and to AF plus 80 ppb of O3 (AF+O3) into fumigation chambers, by determining visible leaf symptoms and changes on gas exchange and on antioxidants. Visible symptoms were daily evaluated. Gas exchange and antioxidants (ascorbic acid and superoxide dismutase) were analyzed at the end of the experiment. All plants from AF+O3 treatment showed leaf injury, characterized by interveinal reddish punctuations on the adaxial surfaces. In average, 15% of leaf injury index and 62% of severity were estimated. Net photosynthesis, stomatal conductance, transpiration rate, ascorbic acid level and superoxide dismutase activity were significantly reduced in those plants, compared to measurements performed in plants exposed to AF only. The results suggest that Abelmoschus esculentus is sensitive to ozone, showing low levels of antixidative defenses and physiological distubances.

Bioindicators plants are important for the evaluation of air quality and Tillandsia usneoides L., an atmospheric epiphyte bromeliad, has been used for this purpose. The present study aims at evaluate the structural pattern of the leaf of this species when exposed to urban air pollutants, and determining whether the leaves present structural parameters that could be used as indicators of such pollutants. Samples of T. usneoides were exposed in Sao Paulo, the biggest city of Brazil, for 8, 16 and 24 weeks, and compared with others kept in a rural area. The urban pollution of Sao Paulo affected the structure of the leaves of T. usneoides causing alterations, especially in the scales, density of stomata and epidermis thickness. Qualitative alterations in the mesophyll were not observed in plants exposed at the polluted sites. These structural characteristics of T. usneoides seem to account for its high tolerance to heavy metal accumulation. The percentage of anomalous scales may potentially be used as an alternative bioindicator parameter.

Psidium guajava ‘Paluma’ saplings were exposed to carbon filtered air (CF), ambient non-filtered air (NF), and ambient non-filtered air + 40 ppb ozone (NF + O3) 8 h per day during two months. The AOT40 values at the end of the experiment were 48, 910 and 12 895 ppb h−1, respectively for the three treatments. After 5 days of exposure (AOT40 = 1497 ppb h−1), interveinal red stippling appeared in plants in the NF + O3 chamber. In the NF chamber, symptoms were observed only after 40 days of exposure (AOT40 = 880 ppb h−1). After 60 days, injured leaves per plant corresponded to 86% in NF + O3 and 25% in the NF treatment, and the average leaf area injured was 45% in NF + O3 and 5% in the NF treatment. The extent of leaf area injured (leaf injury index) was explained mainly by the accumulated exposure of ozone (r2 = 0.91; p

Saplings of Tibouchina pulchra and Psidium guajava, cultivated under standardized soil conditions, were placed in two sites at Cubatão (state of São Paulo, southeast Brazil) to study the effects of air pollution on growth, biomass allocation and foliar nitrogen and fluoride concentrations. Thirty-six potted plants were maintained over two periods of one year (Jul/00 to Jun/01; Dec/00 to Nov/01) at each of two experimental sites with distinct levels of air pollution: Pilões River Valley (PV) with vegetation virtually unaffected by air pollution; and Mogi River Valley (MV) severely affected by pollutants released mainly by chemical, fertilizer, iron and steel industries. For both species, saplings growing at MV showed alterations of growth and biomass allocation, as well as increased leaf concentrations of nitrogen and fluoride. Comparing both experimental periods, the one starting in winter (the driest season in Southeastern Brazil) seemed to affect the saplings more severely, the differences of the measured parameters between MV and PV being higher than in the second period. Multivariate analysis revealed two groups of data: one representing the MV and the other the PV saplings. For both species, saplings growing at MV showed differences in chemical composition, growth and biomass allocation, compared with the PV saplings. The results suggested that seasonal conditions of the first months of sapling exposure (summer or winter) modulate the intensity of responses to pollution stress.

Tillandsia usneoides is an aerial epiphytic bromeliad that absorbs water and nutrients directly from the atmosphere by scales covering its surface. We expanded the use of this species as a broader biomonitor based on chemical and structural markers to detect changes in air quality. The usefulness of such comprehensive approach was tested during the construction and opening of a highway (SP-21) in Sao Paulo State, Brazil. The biomonitoring study was performed from 2009 to 2012, thus comprising the period during construction and after the highway inauguration. Metal accumulation and structural alterations were assessed, in addition to microscopy analyses to understand the metal chelation in plant tissues and to assess the causes of alterations in the number and shape of scale cells. Altogether, our analyses support the use of this species as a wide biomonitor of air quality in urbanized areas.

The distribution of n -alkanes of foliar epicuticular waxes of Psidium guajava (Myrtaceae) exposed to air pollutants was determined by GC-EIMS. Saplings were exposed for two periods of one year (July 2000–June 2001 and December 2000–November 2001) in two experimental sites: Piloes River Valley (PV), where the contamination of air pollutants is relatively low, and Mogi River Valley (MV), which is severely affected by pollutants released by chemical, fertilizer, ceramic, iron and steel industries. On average, total leaf waxes were higher for plants that were exposed initially in the rainy season (December). Leaf waxes showed different n -alkane composition comparing both sites, especially during the first period of exposure (July 2000–June 2001). The main n -alkane waxes in both areas were C 25 , C 26 and C 27 . However, in both experimental periods, an increase of the relative amounts of homologous of shorter carbon chains (C 18 –C 23 ) under pollutants influence was observed. While the total percents of such homologues were on average 9.5 and 10.2 at PV for the first and second experimental periods, the observed percents at MV were on average 15.6 and 13.7, respectively. The results of the present work are in agreement with previous findings that air pollutants affect the synthesis of surface waxes, leading to alterations of the distribution of wax constituents.

In temperate grasses, fructans are the major storage polysaccharides, being accumulated mainly in mature leaf sheaths, and also in the roots. The partitioning of carbohydrates within different organs regulates plant growth and development. The aim of the present work was to analyze the partitioning of water soluble carbohydrates in five different parts (elongating leaf blades, expanded leaf blades, upper and lower segments of the stubble, and roots) of plants of L. multiflorum cv. Lema, in order to contribute to an understanding of soluble carbohydrates distribution in these plants. Soluble carbohydrates and total fructose were analyzed in plants cultivated during 4 months in a glasshouse, by colorimetric, TLC and HPAEC-PAD techniques. Results showed that the greatest portion of total soluble carbohydrates was constituted of free and combined fructose, in all parts of the plants. The stubble contained the highest level of carbohydrates, followed by the elongating leaf blades, expanded leaf blades and roots. The leaf sheaths were not analyzed separately from the stubble, which explains the high levels of carbohydrates found in this part of the plant. The high metabolism of the elongating leaf blades, when compared to that of the expanded leaf blades, could explain the increased amounts of fructans stored in those tissues. Analysis by HPAEC-PAD showed that the elongating leaf blades and the roots had the highest proportions of low molecular weight fructans that could be readily mobilized, supplying the demand of growing tissues in other organs.

We used a short-term bioassay—the Tradescantia stamen-hair assay (TSH)—to evaluate the toxicity of ambient particles with an aerodynamic diameter less than 10 μm sampled in the metropolitan region of Sao Paulo, Brazil. Two exposure locations were selected: downtown Sao Paulo and Caucaia do Alto (mean PM10 levels of 64 and 14 μg/m3, respectively). The experiment was conducted July 11–August 15, 2002, and toxicity was assessed with the Tradescantia stamen-hair assay (TSH) employing clone KU-20 of Tradescantia. Four experimental groups were defined: inflorescences collected from plants cultivated in Caucaia, inflorescences collected from plants cultivated in Sao Paulo (to establish the baseline level of mutations in stamen hairs at both sites), inflorescences collected from plants cultivated in Caucaia and brought to Sao Paulo and maintained in chambers that received ambient air, and inflorescences collected from plants cultivated in Caucaia and brought to Sao Paulo and maintained in chambers that received air passed through a particle filter. The frequency of mutations observed in Caucaia was significantly lower than that in the remaining groups. Flower cuttings brought from Caucaia and receiving ambient air of Sao Paulo showed a rate of mutations similar to that of plants cultivated in Sao Paulo. Filtering particles from the air reduced the rate of mutation but not sufficiently to reach the level of that in Caucaia. The frequency of mutations observed in Sao Paulo was significantly associated with PM10 levels on the fifth day before the opening of the flowers (r = 0.47, p = 0.025). Our results indicate that urban particles play a significant role in the development of pollution-dependent mutations. © 2004 Wiley Periodicals, Inc. Environ Toxicol 19: 578–584, 2004.

This report attempts to bring together contributions from technicians and scientists studying and dealing with the manifold aspects of the São Paulo City Green Belt Biosphere Reserve. It will highlight the understanding by UNESCO of the important role that biosphere reserves can play in the urban setting.

Fully expanded leaves of trees of Tibouchina pulchra were collected at three sites around the industrial complex of Cubatao: the valley of Piloes river (VP), bearing virtually undamaged vegetation; Caminho do Mar (CM), affected mainly by petrochemical industries; and the valley of Mogi river (VM), severely affected by pollution. The amounts of leaf nitrogen, soluble phenols, tannins, lignins and dietary fibers were determined. Leaf area consumed by herbivores and numbers of leaf galls were used to evaluate the influence of fluctuations of those parameters on the leaf damage caused by herbivores. Comparing with the reference site, leaves from VM and CM were shown to have higher amounts of nitrogen and dietary fibers and lower amounts of soluble phenols and tannins. The highest, lowest and intermediate amounts of lignins corresponded, respectively, to CM, VM and reference site. The largest, lowest and intermediate leaf area consumed by herbivores corresponded, respectively, to VM, CM and reference site. The observed percentages of galled leaves were higher at VM and lower at CM in comparison with the reference site. In all sites, the amounts of nitrogen, fibers and lignins in 1997 were higher than in 1996, but the reverse occurred as to the total soluble phenols. Leaf areas consumed by herbivores were not different in 1996 in comparison with 1997, but galled leaf percentages were lower at VM in 1997. Although air pollution damage is evident at the selected sites and certain chemical parameters and leaf herbivory are significantly correlated, the coefficients of explanation in regression analysis are low.

Epiphytic bromeliadTillandsia usneoides was used as a biomonitor of metal atmospheric pollution in the city of Sao Paulo, Brazil. The samples were collected from an unpolluted area and were exposed for 8 weeks in 10 sites of the city and in a control site. The data obtained showed that the control site presented lower concentration for most elements analyzed and the highest concentrations of Na, Cl, Br, K. The highest concentrations of Zn, Cu and V were observed in stations submitted to industrial and vehicular sources. The results obtained for rare earth elements, Al, Fe, Mg, Mn, Rb and Sc indicate mineral dust origin. The elements Ba, As and Sb presented higher values in stations near streets with heavy traffic.

The Tradescantia stamen hair mutation assay (Trad-SHM) was employed for assessing the environmental mutagenesis in two areas of São Paulo City. The study sites were defined as follows: 1) Celso Garcia Avenue, an industrial area on the outskirts of the urban center (Belém neighborhood), with an average daily traffic volume of 8,750 vehicles; 2) Doutor Arnaldo Avenue, in downtown area (Pinheiros neighborhood), with a mostly residential and business offices occupation, with an average daily traffic volume of 46,125 vehicles. The negative control (background) site is located in the city of Jaguariúna, 138 km from São Paulo, in an area of low atmospheric pollution. The mutation frequency observed for Belém was similar to the background for clone 4430, whereas plants exposed in Pinheiros showed significant increases in mutation rate. Positive correlation was observed between mutation frequency and the levels of particulate matter in the atmosphere. This indicated a relationship between mutation frequency and the amount of atmospheric pollution present at the exposure sites in São Paulo City, with special reference to vehicular emissions. O bioensaio de mutação em pêlos estaminais de Tradescantia (clone 4430) (Trad-SHM) foi utilizado para a avaliação comparativa da mutagênese ambiental em duas áreas do centro urbano de São Paulo durante a estação chuvosa, aquela mais propícia à dispersão dos poluentes atmosféricos. Os locais de exposição foram a Avenida Celso Garcia, uma área de pequenas indústrias no Bairro Belém, com um volume médio diário de tráfego de 8.750 veículos automotores e a Avenida Doutor Arnaldo, na área central (Bairro Pinheiros) com ocupação predominantemente residencial e comercial, mas com um volume médio diário de tráfego de 46.125 veículos. O controle negativo foi localizado na cidade de Jaguariúna, a 138 km de São Paulo, em uma área com baixos níveis de poluição atmosférica. Plantas de Tradescantia foram expostas cronicamente em vasos contendo solo padronizado, amostradas bimensalmente e a freqüência de mutações nos pêlos estaminais foi comparada por ANOVA (=0,05). A freqüência de mutações observada para o Belém foi similar ao controle para o clone 4430, enquanto as plantas expostas em Pinheiros apresentaram aumentos significativos nas taxas de mutação. Certa correlação foi observada entre a freqüência de mutações e os níveis de material particulado na atmosfera. Isto indica uma associação entre taxa de mutação detectada pelo ensaio Trad-SHM e a poluição presente em locais sujeitos a maiores níveis de poluição atmosférica, em especial aquela derivada de fontes veiculares.

High deposition of gaseous/particulate fluorides and other air pollutants has resulted in an acidification and probable formation of soluble AlFx complexes in the soil in the vicinity of the industrial complex of Cubatao, SE Brazil. With the present field study we aimed at determining the contribution of F and Al uptake from fluoride-contaminated soil, supposedly as AlFx complexes, to the increase of foliar F and Al contents in saplings of an Al-accumulator tree species (Tibouchina pulchra) which were concomitantly exposed to fluoride-contaminated air and also the proportional contribution of both air and soil contamination to the mentioned foliar accumulation of these elements. The seasonal variations in F and Al accumulation and possible metabolic changes in the plants due to F and Al accumulation were also investigated. The saplings were exposed during three consecutive periods of 16 weeks to: (a) air and soil from a reference site (PVnoF); (b) air or soil from two polluted sites (CM-high air pollution, low F and MV-high air pollution, high F); and (c) both air and soil from these polluted sites. After exposure, the changes in the foliar concentrations of F and Al, the relations between both element contents and their relationships with oxidative stress indicators were determined. The data were grouped in three matrices: PVnoF–CMlwF and PVnoF–MVhgF, taking in account the possible air/soil exposure combinations in each, and soil/air from all sites. The slight F accumulation in plants of PVnoF–CMlwF matrix was a result of higher uptake from soil than from air (54 and 46%, respectively). At PVnoF–MVhgF matrix, the extremely high F accumulation in leaves of T. pulchra could be attributed to the combination of both air and soil contamination (83 and 17%, respectively). T. pulchra always showed higher foliar Al concentrations than 1000 μg g−1 dry mass, mainly after exposure to air and soil of both polluted sites (CMlwF and MVhgF). A highly significant linear regression was estimated between molar Al and F contents, taking in account the data obtained for saplings of T. pulchra cultivated in the different soils and exposed to ambient air of PVnoF, suggesting that both elements were taken as Al–F complexes from soil. The uptake of fluorides from air and/or soil of MVhgF caused significant metabolic changes in T. pulchra, but visible injury supposedly induced by fluorides were observed only when the foliar F contents surpassed 700 μg g−1 dry mass. On the contrary, Al did not cause any metabolic stress to the plants.

The risks posed by nutrient deposition due to air pollution on ecosystems and their respective services to human beings can be appropriately estimated by bioindicator plants when they are well acclimated to the study region environmental conditions. This assumption encouraged us to comparatively evaluate the accumulation potential of ryegrass cv. Lema and guava cv. Paluma macro and micronutrients. We also indicated the most appropriate species for biomonitoring nutrient contamination risks in tropical areas of Southeastern Brazil, which are characterized by marked dry and wet seasons and complex mixtures of air pollutants from different sources (industries, vehicle traffic and agriculture). The study was conducted in 14 sites with different neighboring land uses, within the Metropolitan Region of Campinas, central-eastern region of Sao Paulo State. The exposure experiments with ryegrass and guava were consecutively repeated 40 (28 days each) and 12 (84 days each) times, respectively, from Oct/2010 to Sept/2013. Macro and micronutrients were analyzed and background concentrations and enrichment ratios (ER) were estimated to classify the contamination risk within the study region. Significantly higher ER suggested that ryegrass were the most appropriate accumulator species for N, S, Mg, Fe, Mn, Cu and Zn deposition and guava for K, Ca, P and B deposition. Based on these biomonitoring adjustments, we concluded that the nutrient deposition was spatially homogeneous in the study area, but clear seasonality in the contamination risk by nutritional inputs was evidenced. Significantly higher contamination risk by S, Fe, K and B occurred during the dry season and enhanced contamination risk by Mn, Cu and Zn were highlighted during the wet season. Distinctly high contamination risk was estimated for S, Fe and Mn in several exposure experiments.

Psidium guajava L., Psidium cattleyanum Sabine and Mangifera indica L. were tested under field conditions as possible tropical bioindicators of industrial air pollution. The study was performed around the industrial complex of Cubatão, SE Brazil, which comprises 23 industries, including fertilizer, cement, chemical, petrochemical, and steel plants, with 110 production units and 260 emission sources of pollutants. Saplings were exposed to environmental conditions during four periods of 16 weeks each (September 1994–September 1995), at four different sites in the coastal mountains near the industrial complex: the Valley of Pilões River (VP), the reference area; the Valley of Mogi River (VM), with high contamination of particulate matter, fluorides (F), sulfur (S) and nitrogen (N) compounds; Caminho do Mar (CM1, CM2), mainly affected by organic pollutants, S and N compounds, and secondary pollutants; and Paranapiacaba (PP), affected by secondary pollutants, such as ozone. M. indica did not adapt to the climatic conditions at the exposure sites. In the two Psidium species, the presence of visible symptoms, root/shoot ratio, foliar contents of F, S and N, amounts of ascorbate (AA) and water-soluble thiols (–SH), as well as peroxidase activity (POD) were determined. P. guajava showed higher foliar accumulation of F, S and N, more pronounced alterations of biochemical indicators, and less visible leaf injury than P. cattleyanum. P. guajava may be used as an accumulative indicator in tropical climates, while further studies will be needed before P. cattleyanum might be applied as a sensitive species in biomonitoring programs. Keywords: Biomonitoring, Industrial air pollution, Fluoride, Sulfur, Nitrogen, Psidium guajava, Psidium cattleyanum

Air pollutant emissions from the industrial complex of Cubatao, SE-Brazil, have caused a severe decline of the Atlantic Forest in that region. In order to test the influenceof air pollution on the mineral nutrition of trees, leaves of the native species Tibouchina pulchra Cogn. (Melastomataceae), Miconia pyrifolia Naud. (Melastomataceae) and Cecropia glazioui Snethl. (Cecropiaceae) were sampled during winter and summer seasons at four sites with different pollution characteristics. Additionally, saplings of T. pulchra were cultivated in uniform soil and exposed to ambient air at the same experimentalsites for periods of 16 weeks. In both kinds of leaf samples, the concentrations of macro-nutrients were determined and nutrient ratios calculated. In leaves of mature T. pulchraand C. glazioui growing at polluted sites N, P and S levels were significantly higher than in trees from the reference area. With respect to K contents, C. glaziouishowed an increase, T. pulchra a decrease when compared to reference trees. Mg and Ca concentrations generally did not exhibit great variations. As a consequence of the changes in mineral contents nutrient ratios (N/K, N/Ca, S/K, S/Ca) shifted to higher values. The results of the exposure experiments together with data on pollutant concentrations inambient air and rain water demonstrated that atmosphericdeposition to the plants and pollution effects on the soilchemistry are the main reasons for the observed alterations inmineral nutrition of trees.

The predicted increases in emissions of primary pollutants in many rapidly industrializing countries may have severe consequences for the health and productivity of forest trees and agricultural crops. This paper presents a review of air pollution impacts on vegetation in developing countries by summarising information describing the direct impacts to vegetation caused by a number of air pollutants (sulphur dioxide (SO2), nitrogen oxides (NOx), ozone (O3) and Suspended Particulate Matter (SPM)). This information has been collected by experts from a number of rapidly industrializing countries in Asia, Latin America and Africa and includes observations of visible injury in the field and the use of transect studies and controlled experimental investigations to ascribe damage to different pollutant concentrations. The ability to synthesise this information to define exposure-response relationships and subsequent air quality guidelines similar to those established in North America and Europe is assessed. In addition, the use of regional and global models describing pollution concentrations is discussed with reference to assessing the extent of adverse impacts and identifying regions likely to be most at risk from air pollution, both for the present day and in the future. The evidence summarised in the paper clearly shows that current pollutant concentrations experienced in many developing countries, particularly Asia, can result in severe damage to vegetation and that without appropriate control measures such damage is likely to worsen in the future as pollutant emissions increase.

This study was designed to determine the clastogenicity of particulate matter (aerodynamic diameter smaller than 10 microm) in the urban polluted air in the city of São Paulo. The Tradescantia-micronucleus (Trad-MCN) assay was used throughout this study to evaluate the clastogenicity of the extracts of the particulate matter. Tradescantia pallida (Rose) Hunt. cv. purpurea, an indigenous cultivar, was used in the Trad-MCN assay. The efficacy of this plant material for the Trad-MCN assay was validated with dose-response studies using formaldehyde and beta radiation. Dose-response curves were established with these known mutagens. The extracts of the PM10 particles at concentrations between 5 and 50 ppm induced a dose-related increase in MCN frequencies. The results indicate that T. pallida is equally sensitive to mutagens as the standard Tradescantia clone 4430 or 03 and the particulate matter in the urban air are clastogenic to the chromosomes of this plant. Inhalation of these particles by urban dwellers may affect their health by inducing similar genetic damage.

The industrial complex of Cubatao, SE-Brazil, is presented as a typical example of the increasing environmental problems of developing and threshold countries. As a consequence of high air pollutant emissions the Atlantic Rain Forest shows severe decline symptoms. Studies with native tree species including field investigations in the stand and exposure experiments with young trees revealed an accumulation of toxic elements like fluoride and sulphur in the leaves, alterations of mineral economy, metabolic changes typical for stress situations and modifications of growth characteristics. These findings are discussed with respect to the vegetation risk by air pollution.

We assessed the level of atmospheric contamination by S, N and metals before, during and after the installation of a new thermoelectric plant that provides power to an oil refinery in Cubatao, SE Brazil. We measured the foliar accumulation in Lolium multiflorum "Lema" with the aim of evaluating risks to the Atlantic Rainforest that grows in the region. Al, Co, Cr, Cu, K, N, Ni, S, V and Zn were appropriate markers of the new air contamination profile associated with the modern technology. With the exception of V, the leaf contents of these elements significantly increased between the pre-operation to post-operation phases (Al, Co, N, K, S), or only during the transition phase (Zn, Cu, Cr, Ni), and returned to the previous levels after the total shutdown of the old system. Therefore, the expected environmental gain was not achieved with the installation of the new technology.

RESUMO - (Produção de serapilheira e retorno de nutrientes em um trecho de Mata Atlântica secundária, na Reserva Biológica de Paranapiacaba, SP). A produção e o conteúdo de nutrientes da serapilheira foram quantificados em área de Mata Atlântica na Reserva Biológica de Paranapiacaba, estado de São Paulo, não afetada pela poluição aérea do pólo industrial de Cubatão. Os objetivos do estudo foram realizar uma comparação com resultados de trabalho semelhante, desenvolvido em áreas da Reserva mais e menos afetadas pela poluição e determinar a extensão dos impactos desse estresse naquela região. Utilizaram-se 30 coletores de 0,25 m² com coletas mensais durante um ano (abr/88 a mar/89). As amostras mensais foram separadas em folhas, ramos, partes reprodutivas e miscelânea, pesadas e analisadas quanto aos teores de N, P, K, Ca, Mg e S. A produção anual de serapilheira total foi de 7007 kg.ha-1 (72% de folhas, 22% de ramos, 4% de miscelânea e 2% de partes reprodutivas). A produção de serapilheira foi contínua ao longo do ano, sem apresentar efeitos de sazonalidade. As folhas apresentaram os maiores teores de Ca e Mg, e a miscelânea, os maiores de N, P, K e S. O retorno de macronutrientes pela serapilheira total produzida obedeceu à seqüência decrescente dada por N>Ca>S>K>Mg>P. Com base em comparações com resultados obtidos em outros estudos desenvolvidos em florestas tropicais e na própria Reserva de Paranapiacaba, conclui-se que o trecho da floresta estudado não apresenta alterações causadas pela poluição nessa etapa da ciclagem de nutrientes. ABSTRACT - (Litter production and nutrient return in a portion of the secondary Atlantic Forest, at the Biological Reserve of Paranapiacaba, SP). The litter production and nutrient contents have been quantified in an area of Atlantic Forest at the Biological Reserve of Paranapiacaba, in the state of São Paulo, free from the impact of the air pollution from the industrial complex of Cubatão. The objectives of this study were to compare the results obtained here with those of a similar study performed at more and less affected areas of the Reserve and to determine the extension of the air pollution impacts at that region. Thirty litter trays with 0,25 m² were randomly distributed, sampling the litter monthly during one year (Abr/88 to Mar/89). The samples were sorted by leaves, twigs, reproductive parts and miscellaneous, weighed and N, P, K, Ca, Mg and S concentrations were determined. The annual total litter production was 7007 kg.ha-1 (72% of leaves, 22% of twigs, 4% of miscellaneous and 2% of reproductive parts) The litterfall and nutrient fluxes were continuous along the year, without any clear seasonal pattern. Leaves showed higher levels of Ca and Mg while miscellaneous presented more N, P, K and S. The macronutrient return through total litterfall followed the decreasing sequency N>Ca>S>K>Mg>P. Through comparison with results from other studies on tropical forests and on the Paranapiacaba Reserve itself, it is concluded that the part of the forest here studied does not present changes caused by air pollution in this step of nutrient cycling.

The present study aimed to establish the seasonal variations in the redox potential ranges of young Tibouchina pulchra plants growing in the Cubatao region (SE Brazil) under varying levels of oxidative stress caused by air pollutants. The plants were exposed to filtered air (FA) and non-filtered air (NFA) in open-top chambers installed next to an oil refinery in Cubatao during six exposure periods of 90 days each, which included the winter and summer seasons. After exposure, several analyses were performed, including the foliar concentrations of ascorbic acid and glutathione in its reduced (AsA and GSH), total (totAA and totG) and oxidized forms (DHA and GSSG); their ratios (AsA/totAA and GSH/totG); the enzymatic activities of superoxide dismutase (SOD), ascorbate peroxidase (APX), catalase (CAT) and glutathione reductase (GR); and the content of malondialdehyde (MDA). The range of antioxidant responses in T. pulchra plants varied seasonally and was stimulated by high or low air pollutant concentrations and/or air temperatures. Glutathione and APX were primarily responsible for increasing plant tolerance to oxidative stress originating from air pollution in the region. The high or low air temperatures mainly affected enzymatic activity. The content of MDA increased in response to increasing ozone concentration, thus indicating that the pro-oxidant/antioxidant balance may not have been reached.

The Atlantic Rain Forest near the industrial complex of Cubatao, south-eastern Brazil, suffers from the impact of severe air pollution. Gaseous and particulate fluorides which are emitted by fertiliser plants are assumed to play an important role in the forest decline. In order to obtain information on the air pollution situation and the spatial and temporal distribution of pollution effects, standardised bioindication methods from temperate climates were introduced and applied during a three-year study. A sensitive Gladiolus cultivar developed typical fluoride-induced leaf lesions in areas affected by airborne fluorides, and Lolium multiflorum cultures accumulated large quantities of fluoride. Highly significant linear regression was found between foliar fluoride contents of both species as well as between leaf damage and fluoride accumulation in Gladiolus plants. By using these indicator species, four different areas of the region were identified with respect to vegetation risk by airborne fluorides.

Air pollutant emissions from the industrial complex of Cubatao, Brazil, have led to a severe deterioration of the Atlantic Forest ecosystem. In a field study, leaves of the tree speciesTibouchina pulchra, Miconia pyrifolia, andCecropia glazioui were collected at four sites with different pollution characteristics. Leaf fluoride contents of the three species were found to be highly elevated in a valley near to fertilizer factories. In an area further from the emission sources, which in the past had been affected by fluoride pollution, fluoride concentrations inTibouchina andMiconia continued to be elevated. Preliminary exposure experiments using Tibouchina seedlings as accumulative indicators are reported.

Saplings of the tropical trees Tibouchina pulchra (Cham.) Cogn., Caesalpinia echinata Lam., and Psidium guajava L. cv. Paluma were exposed in open-top chambers with charcoal filtered air and measurements of gas exchange and chlorophyll fluorescence were made before (t1) and after exposure to non-filtered air plus O3 (t2), simulating 6-h peaks of O3 similar to those observed in Sao Paulo city (SE Brazil, reaching an AOT40 of 641 nmol mol−1). After the fumigation, the net photosynthetic rate, stomatal conductance, transpiration rate, and Fv/Fm were reduced (p

This study aimed to analyze critically the potential of Ipomoea nil'Scarlet O'Hara' for O(3) biomonitoring in the sub-tropics. Four field experiments (one in each season of 2006) were carried out in a location of the city of São Paulo mainly polluted by O(3). Each experiment started with 50 plants, and lasted 28 days. Sub-lots of five plants were taken at intervals between three or four days long. Groups of four plants were also exposed in closed chambers to filtered air or to 40, 50 or 80 ppb of O(3) for three consecutive hours a day for six days. The percentage of leaf injury (interveinal chloroses and necroses), the concentrations of ascorbic acid (AA) and the activity of superoxide dismutase (SOD) and peroxidases (POD) were determined in the 5th, 6th and 7th oldest leaves on the main stem of the plants taken in all experiments. Visible injury occurred in the plants from all experiments. Seasonality in the antioxidant responses observed in plants grown under field conditions was associated with meteorological variables and ozone concentrations five days before leaf analyses. The highest levels of antioxidants occurred during the spring. The percentage of leaf injury was explained (R(2) = 0.97, p0.01) by the reduction in the levels of AA and activity of POD five days before the leaf analyses and by the reduction in the levels of particulate matter, and enhancement of temperature and global radiation 10 days before this same day. Although I. nil may be employed for qualitative O(3) biomonitoring, its efficiency for quantitative biomonitoring in the sub-tropics may be compromised, depending on how intense the oxidative power of the environment is.

This study extends the current knowledge regarding the use of plants for the passive accumulation of anthropogenic PAHs that are present in the atmospheric total suspended particles (TSP) in the tropics and sub-tropics. It is of major relevance because the anthropic emissions of TSP containing PAHs are significant in these regions, but their monitoring is still scarce. We compared the biomonitor efficiency of Lolium multiflorum ‘Lema’ and tropical tree species ( Tibouchina pulchra and Psidium guajava ‘Paluma’) that were growing in an intensely TSP-polluted site in Cubatao (SE Brazil), and established the species with the highest potential for alternative monitoring of PAHs. PAHs present in the TSP indicated that the region is impacted by various emission sources. L. multiflorum showed a greater efficiency for the accumulation of PAH compounds on their leaves than the tropical trees. The linear regression between the logBCF and logKoa revealed that L. multiflorum is an efficient biomonitor of the profile of light and heavy PAHs present in the particulate phase of the atmosphere during dry weather and mild temperatures. The grass should be used only for indicating the PAHs with higher molecular weight in warmer and wetter periods.

As a result of air pollutant emissions from the industrial complex of Cubatão, Brazil, the Atlantic Forest vegetation of the Serra do Mar shows severe and widespread damage. In order to obtain information on the type, intensity and causes of the vegetation damage, bioindicator plants were exposed at different distances from the emission sources. Air-pollution-induced effects were evaluated by estimation of visible injury symptoms and chemical analyses of leaves. The results prove the occurrence of phytotoxic levels of photochemical oxidants in wide parts of the research area. Intense fluoride-induced damage and high leaf fluoride concentrations were found in a valley downwind of fertiliser industries. The study showed that some of the traditional standardised bioindication methods from temperate climates may be successfully employed in biomonitoring programmes in tropical and subtropical regions.

The Tradescantia micronucleus test is a sensitive bioassay for mutagenesis that may be employed both under field and laboratory conditions. This test has been standardized mostly on the basis of the results obtained with clone 4430. However, this clone is not well adapted to tropical weather, frequently showing problems with growth and flowering. In addition, it is attacked by parasites and insects, a fact that limits its use in field studies aiming at the biomonitoring of air pollution. In the city of São Paulo, Tradescantia pallida (Rose) Hunt. var. purpurea Boom is widely distributed as an ornamental plant in gardens and along roadsides and streets, mostly because of its natural resistance and its easy propagation. In this report, we present dose-response curves indicating that the sensitivity of T. pallida and clone 4430 to X-radiation (1, 10, 25 and 50 cGy) is similar. The results confirm our previous suggestion that T. pallida represents a good alternative for in situ mutagenesis testing in tropical regions, especially biomonitoring studies in which the exposure conditions may not be fully controllable. Made available in DSpace on 2017-09-19T00:13:17Z (GMT). No. of bitstreams: 1 Suyamapollen.pdf: 129033 bytes, checksum: e7dd750df919db6ef13cd706f7a5cf22 (MD5) Previous issue date: 2007-07-12

Reactive oxygen species can be produced in leaf cells during normal aerobic metabolism or in a variety of exogenous factors, which may cause oxidative damage to plants, unless they have an efficient antioxidant defense system, consisting of enzymatic and non-enzymatic substances. This work raised the hypothesis that plants of Ipomoea nil cv. Scarlet O'Hara, a native species and ornamental vine of the tropics, might tolerate oxidative stress factors imposed by natural fluctuations in weather conditions through changes in the antioxidant profile.The objective of this study was to determine the variations in three leaf antioxidants in plants growing inside a greenhouse without air pollutants and exposed to varying meteorological conditions throughout the four seasons of the year and to observe if such variations are related to the oscillations in meteorological factors. Four experimental campaigns were carried out, one in each season of 2006. Each campaign lasted 28 days and started with 45 plants. Ascorbic acid (AA) concentrations and superoxide dismutase (SOD) and peroxidase (POD) activities were determined in leaves of five plants in nine sampling days of each campaign. The antioxidant responses oscillated throughout the year. The highest values were found during the spring. This seasonal antioxidant profile was associated to variations in temperature, relative humidity and global radiation. Plants of this cultivar may then tolerate oxidative stress naturally imposed by meteorological conditions.

We aimed to verify whether hydrogen peroxide (H(2)O(2)) accumulation and cell death are detected early in three bioindicators of ozone (O(3)), Nicotiana tabacum 'Bel-W3', Ipomoea nil 'Scarlet O'Hara' and Psidium guajava 'Paluma', and whether environmental factors also affect those microscopic markers. The three species were exposed to chronic levels of O(3) in a subtropical area and a histo-cytochemical technique that combines 3,3'-diaminobenzidine (DAB) with Evans blue staining was used in the assessments. The three species accumulated H(2)O(2), but a positive correlation with O(3) concentration was only observed in N. tabacum. A positive correlation between O(3) and cellular death was also observed in N. tabacum. In I. nil and P. guajava, environmental factors were responsible for symptoms at the microscopic level, especially in P. guajava. We conclude that the most appropriate and least appropriate bioindicator plant for O(3) monitoring in the subtropics are N. tabacum 'Bel-W3' and P. guajava 'Paluma', respectively.

The present study was made to check if the Trad-MCN bioassay, developed with inflorescences of Tradescantia pallida cv. Purpurea, might discriminate genotoxic risks in areas of the city of Santo Andre (SE Brazil) contaminated by different air pollutants, and periods of the year when risks are higher, and to determine if the variations in the frequency of micronuclei (MCN) can be explained by environmental factors that characterize the stressful situation in each site. Potted plants were exposed in sites highly contaminated by ozone (Capuava and School) and in sites reached by high vehicular emissions (downtown and Celso Daniel Park). Pedroso Park, far from the polluted areas, was taken as reference. From September 2003 to September 2004, 20 young inflorescences were collected twice a week from each place and the frequencies of MCN were estimated. The environmental conditions observed in the polluted sites were stressful enough to promote an increase of MCN, mainly in sites reached by high vehicular emissions. But MCN rates in Capuava and at Celso Daniel Park could not be predicted only by pollutants which characterized the air contamination in these sites. More severe weather conditions, mainly low temperature, relative humidity and rainfall, caused an increase of MCN. Improvement of the biomonitoring system is recommended to minimize this negative influence of weather factors.

Nicotiana tabacum ‘Bel W3’ is a widely used sensitive bioindicator for ambient ozone, but it is rarely used in tropical countries. Our goal was to determine the suitability of this plant for biomonitoring ozone in the city of Sao Paulo by evaluating the relationships between leaf necroses and ozone under field conditions and measurements of chlorophyll a fluorescence and antioxidants in plants exposed to different concentrations of ozone in closed chambers. While a weak linear relationship between leaf injury and ozone concentrations (R2 = 0.10) was determined in the field, a strong linear relationship was observed in the chamber experiments. Maximum leaf injury was observed in plants submitted to 40 ppb, which coincided with a significant decrease in fluorescence and total ascorbic acid. The relationship between leaf damage observed in the field and ozone was improved when the concentrations were limited to 40 ppb (R2 = 0.28).

Tibouchina pulchra saplings were exposed to carbon filtered air (CF), ambient non-filtered air (NF) and ambient non-filtered air+40 ppb ozone (NF+O3) 8 h per day during two months. The AOT40 values at the end of the experiment were 48, 910 and 12,895 ppb h(-1), respectively, for the three treatments. After 25 days of exposure (AOT40=3871 ppb h(-1)), interveinal red stippling appeared in plants in the NF+O3 chamber. In the NF chamber, symptoms were observed only after 60 days of exposure (AOT40=910 ppb h(-1)). After 60 days, injured leaves per plant corresponded to 19% in NF+O3 and 1% in the NF treatment; and the average leaf area injured was 7% within the NF+O3 and 0.2% within the NF treatment. The extent of leaf area injured (leaf injury index) was mostly explained by the accumulated exposure of ozone (r2=0.89; p

Caesalpinia echinata Lam. (brazilwood) is an endangered tree species occurring along the eastern coast of Brazil from latitudes 5°56´S to 22°56´S. With such a range of distribution it is expected that temperature and daylength may affect plant development, which was examined in this study. One- and five-year-old saplings were grown under controlled photoperiods of 8 h, 12 h and 20 h, and in a greenhouse under natural light during 16 months. In another experiment, one-year-old saplings were cultivated for six months in a growth cabinet, with reduced maximum temperature, and in the greenhouse. Leaf number, stem height and stem diameter at the soil surface were evaluated every two months (experiment 1) or every month (experiment 2). In experiment 1, no significant effect of photoperiod on growth of saplings was observed. The increase of leaf number with time followed a polynomial model, and the slope of the curves differed significantly for saplings of the two ages. Stem height increased linearly in younger saplings and fitted a polynomial curve in older saplings. Stem diameter enlarged linearly with time in all saplings. Growth parameters were significantly related to high temperatures. In experiment 2, significant regressions between growth and the maximum daily temperatures recorded were also found for increase of leaf number and stem height increment. Our results show that vegetative growth of the saplings of this tropical species is affected by temperature but not by photoperiod. Caesalpinia echinata Lam. (pau-brasil) é uma espécie arbórea ameaçada, que ocorre na costa leste do Brasil, em latitudes de 5°56´S a 22°56´S. Em tal faixa de distribuição espera-se que a temperatura e o comprimento do dia possam afetar o desenvolvimento da planta, o que foi investigado no presente estudo. Plantas jovens com um e cinco anos de idade foram cultivadas sob fotoperíodos controlados de 8 h, 12 h e 20 h e em casa de vegetação, sob luz natural, durante 16 meses. Em outro experimento, plantas jovens com um ano de idade foram cultivadas por seis meses em câmara de crescimento, onde a temperatura máxima foi reduzida, e em casa de vegetação. O número de folhas, a altura do caule e o diâmetro do caule à superfície do solo foram avaliados a cada dois meses (experimento 1), ou mensalmente (experimento 2). No experimento 1, não foi encontrada alteração de crescimento nas plantas crescendo sob os diferentes tratamentos fotoperiódicos. Foi possível ajustar regressão polinomial para o aumento do número de folhas, em função do tempo, com diferença significativa na inclinação da curva para as plantas das duas idades. A altura do caule aumentou linearmente nas plantas mais jovens e, nas mais velhas, tal parâmetro ajustou-se à regressão polinomial. As medidas de crescimento relacionaram-se significativamente com as médias das temperaturas máximas diárias registradas. No experimento 2, também foram encontradas regressões significativas entre o crescimento das plantas e as temperaturas máximas para aumento do número de folhas e da altura do caule. Os resultados mostraram que o crescimento vegetativo dessa espécie tropical é afetado pela temperatura e não pelo fotoperíodo.

The aims of this study were to determine clastogenic responses of Tradescantia pallida cv. Purpurea to naphthalene (NAPH) by means of the bioassay Trad-MCN with inflorescences of T. pallida cv. Purpurea and to verify if this assay might be an indicator of the potential risk imposed in a workplace, where solid insecticide containing NAPH is usually applied. The clastogenic potential of NAPH was assessed by using static and dynamic experimental systems. In both systems, increased micronucleus frequencies were observed in inflorescences submitted to increasing concentrations of solid or gaseous NAPH. The evident clastogenicity verified in inflorescences exposed experimentally to 25–50 mg m −3 of NAPH during 6 h points to a narrow threshold of plant sensitivity, indicating risks under lower NAPH levels than the standards established by OSHA and therefore revealing its suitability for biomonitoring purposes. However, the clastogenic risk should be carefully investigated by other monitoring methods if human health is taken into consideration.