ABSTRACT Copper (Cu)-contaminated soils are becoming more common, and phytoremediation is an effective strategy for reducing the negative effects of Cu on soils. Tree species are commonly used for this technique because they act as a barrier to this type of contamination. It is necessary to evaluate Cu tolerance and toxicity thresholds together with the harm this metal causes to plants. The objective of the current study was to investigate the tolerance of Handroanthus heptaphyllus plants to Cu through morpho-physiological, biochemical, and tissue Cu concentration analyses. H. heptaphyllus seedlings were subjected to nutrient solutions with varying concentrations of copper: 0, 5, 32, 64, 96, and 128 µM Cu in a hydroponic system. We conducted a morpho-physiological trait analysis on shoot height, root length, dry weight, morphological variables of the root system, leaf area, and photosynthetic variables. In addition, we also looked into photosynthetic pigments, antioxidant enzymes, lipid peroxidation, hydrogen peroxide concentration, and Cu accumulation in tissues. The values obtained for variables such as dry weight and pigments did not show significant differences, regardless of Cu concentration. Moreover, photosynthetic and transpiration rates were negatively affected only at the highest Cu concentration (128 µM). Overall, excess Cu had no effect on Handroanthus heptaphyllus below 128 µM. Cu accumulated mainly in the roots without a decrease in biomass, which could indicate the tolerance of the species to this metal as well as its great potential in the phytostabilization of Cu in contaminated soils.

RESUMO Solos contaminados com cobre (Cu) são um problema crescente, e o uso da fitorremediação tem evidenciado resultados positivos na redução dos efeitos nocivos desse elemento nos solos. Espécies arbóreas têm sido amplamente utilizadas para esta técnica, pois funcionam como barreira a esse tipo de contaminação. Portanto, é necessário avaliar os limites de tolerância/toxicidade ao Cu, bem como os danos causados por este metal nas plantas. Assim, o presente estudo teve como objetivo investigar a tolerância de plantas de Handroanthus heptaphyllus ao Cu através de análises morfofisiológicas e bioquímicas, bem como a concentração de Cu nos tecidos. Mudas de H. heptaphyllus foram submetidas a diferentes concentrações de Cu adicionadas na solução nutritiva: 0,5, 32, 64, 96 e 128 μM Cu em sistema hidropônico. Foram analisados atributos morfofisiológicos, como altura da parte aérea e comprimento da raiz, massa seca, variáveis morfológicas do sistema radicular, área foliar e variáveis fotossintéticas. Além disso, foram investigados pigmentos fotossintéticos, enzimas antioxidantes, peroxidação lipídica, concentração de peróxido de hidrogênio e Cu acumulado nos tecidos. Os valores registrados para variáveis como massa seca e pigmentos não apresentaram diferença significativa, independentemente das concentrações de Cu. Além disso, as taxas fotossintéticas e transpiratórias foram afetadas negativamente apenas na maior concentração de Cu (128 μM). No geral, a espécie Handroanthus heptaphyllus foi afetada pelo excesso de Cu apenas em 128 μM. O Cu se acumulou principalmente nas raízes, sem registrar diminuição da biomassa, o que pode indicar a tolerância da espécie a esse metal, bem como seu grande potencial para ser utilizado na fitoestabilização de Cu em solos contaminados com este metal.

Abstract Cadmium (Cd) is a heavy metal that may bring about harmful pollution of water and soil. Phytoremediation involving elements beneficial for plant development is a strategy to alleviate this problem. Silicon (Si) has shown potential in neutralizing biotic and abiotic stresses in plants, especially those caused by heavy metals. Thus, the aim of this study was to evaluate whether Si could mitigate the effects of Cd toxicity on growth, photosynthetic activity, and oxidative stress in seedlings of Enterolobium contortisiliquum. The experiment consisted of a completely randomized design with four replications. In addition to a control treatment, the following amounts of Cd, Si, and combinations were added to the complete nutrient solution: 1.5 mM Si; 3.0 mM Si; 1.5 mM Si + 100 μM Cd; 3.0 mM Si + 100 mM Cd; 100 mM Cd. Each sampling unit consisted of a tray containing 16 plants. Silicon concentrations of 1.5 and 3.0 Si mM were adequate to mitigate the effects of cadmium toxicity on Enterolobium contortisiliquum seedlings. The results showed that Si promoted photosynthetic activity, increased total chlorophyll, and decreased shoot lipid peroxidation in the presence of Cd. Furthermore, the lack of significant differences in shoot and root dry weight among treatments and low peroxidation content in roots suggest that E. contortisiliquum is tolerant to cadmium.

Resumo O cádmio (Cd) é um metal pesado nocivo capaz de poluir a água e o solo. A fitorremediação ligada a elementos benéficos para o desenvolvimento vegetal é uma estratégia para amenizar esse problema. O silício (Si) tem mostrado potencial para neutralizar estresses bióticos e abióticos em plantas, principalmente aqueles causados por metais pesados. Assim, o objetivo deste estudo foi avaliar os efeitos do Si sobre a toxicidade do Cd no crescimento, na atividade fotossintética e no estresse oxidativo em mudas de Enterolobium contortisiliquum. O experimento constou de um delineamento inteiramente casualizado, com quatro repetições. Além de um tratamento controle, as seguintes combinações de Cd e Si foram adicionadas à solução nutritiva completa: 1,5 mM de Si; Si 3,0 mM; 1,5 mM de Si + 100 μM de Cd; 3,0 mM de Si + 100 μM de Cd; 100 μM Cd. Cada unidade amostrai consistiu de uma bandeja contendo 16 plantas. Os resultados mostraram que o Si promoveu a atividade fotossintética, aumentou a clorofila total e diminuiu a peroxidação lipídica da parte aérea na presença de Cd. As concentrações de 1.5 e 3.0 Si mM de silício podem ser consideradas adequadas para amenizar os efeitos da toxicidade de cádmio em mudas de Enterolobium contortisiliquum. Além disso, a ausência de diferenças significativas no peso seco da parte aérea e da raiz entre os tratamentos e baixo teor de peroxidação nas raízes sugerem que E. contortisiliquum é tolerante ao cádmio.

ABSTRACT Plantations with native tree species, which emphasize biodiversity conservation, may not succeed because of a lack of forestry knowledge about the native species. Cabralea canjerana is an important tree species, which is rarely present in area restoration programs because of the difficulty in establishing it in plantations. Despite this, the species is also known for its adaptation to different light conditions. Therefore, this research sought to answer: a) What is the appropriate light level for the initial establishment of Cabralea canjerana seedlings in the field? b) Does seasonality influence the morphological and physiological attributes of Cabralea canjerana plants? The treatments used were: four shade intensities (0, 18, 50 and 70%) and two seasonal periods (spring-summer and autumn-winter). Survival was evaluated at 30 and 360 days after planting, while the morphological and physiological attributes were evaluated at 180 (spring-summer) and 360 (autumn-winter) days after planting. We suggest that Cabralea canjerana be classified as a moderately shade-tolerant species, considering that even in a region with four well-defined seasons, like the one in the present study, its mortality rate was high in full sun, a fact that is corroborated by the morphological and physiological parameters. The planting of Cabralea canjerana seedlings in full sunlight is not appropriate because it causes low seedling survival. It is recommended that planting be carried out under 50% shading. Seasonality influenced the morphological and physiological attributes of Cabralea canjerana plants.

SUMMARY: Light is an important environmental factor in the establishment of vegetation. The knowledge of the behavior of the species in response to light demand for survival and growth in the field becomes essential. Thus, the present study aimed at evaluating the survival and initial growth of Myrocarpus frondosus seedlings under different levels of shade in the field. The treatments used were: 0 % (full sun); 18 %; 50 % and 70 % shading in a randomized block design. The survival of seedlings was evaluated 30 and 540 days after planting (d.a.p.) and the morphological attributes height (H), stem diameter (DC) and H/DC ratio every 90 days. Leaf area, leaf dry matter, dry matter of stem and branches and dry matter of shoot were obtained 540 d.a.p. The analyses of the physiological attributes fluorescence of chlorophyll a and photosynthetic pigments were performed 180, 360 and 540 d.a.p. The use of shading in the planting of Myrocarpus frondosus influences the survival and the morphological and physiological attributes of the species. The morphological and physiological attributes of Myrocarpus frondosus plants show that the species requires shading of 50 to 70 % in its initial growth phase in the field (540 d.a.p.). It is recommended to use the species in sub-forest enrichment plantations and in consortium with other species more demanding in light.

RESUMEN: La luminosidad es un factor ambiental importante en el establecimiento de la vegetación, siendo imprescindible el conocimiento del comportamiento de las especies en respuesta a la demanda de luz para supervivencia y crecimiento en el campo. El presente estudio tuvo como objetivo evaluar la supervivencia y el crecimiento inicial de plantas de Myrocarpus frondosus bajo diferentes niveles de sombreamiento en el campo. Los tratamientos utilizados fueron 0 % (pleno sol), 18 %, 50 % y 70 % de sombreamiento en un diseño de bloques al azar. La supervivencia de las plantas fue evaluada a los 30 y 540 días después de la plantación (ddp) y los atributos morfológicos altura (H), diámetro del cuello (DAC) y relación H/DC cada 90 días. A los 540 ddp se obtuvo el área foliar, materia seca foliar, materia seca del tallo y ramas y la materia seca de la parte aérea. Los análisis de los atributos fisiológicos fluorescencia de la clorofila α y los pigmentos fotosintéticos fueron realizados a los 180, 360 y 540 ddp. La utilización de sombreamiento en la plantación de Myrocarpus frondosus evidencian que la especie necesita de 50 y 70 % de sombra en la fase inicial de crecimiento en el campo (540 ddp). Se recomienda el uso de la especie en plantaciones de enriquecimiento de sub bosque y en consorcio con otras especies más exigentes en luminosidad.

RESUMO A aplicação de doses de fósforo (P) no solo pode aumentar o crescimento de espécies arbóreas nativas de interesse econômico e ambiental, como a Cordia trichotoma. Assim, esta pesquisa tem por objetivo avaliar parâmetros morfológicos e fisiológicos em mudas de C. trichotoma cultivadas em solo com aumento do teor de P. O experimento foi conduzido em casa de vegetação, em vasos com 2,5 dm-3 de solo, com quatro doses de P (0, 150, 300 e 450 mg dm-3) e seis repetições. O teor de P no solo, as concentrações de P nas folhas, os atributos morfológicos (altura, diâmetro do coleto, matéria seca aérea, matéria seca radicular e área foliar) e os atributos fisiológicos (teor de pigmentos fotossintéticos e fluorescência da clorofila a) foram determinados aos 180 dias após o transplante. O incremento no teor de P disponível no solo permitiu maior absorção desse elemento pelas raízes das plantas, elevando a concentração nas folhas. Isso favoreceu o metabolismo energético das plantas, proporcionando maior crescimento. Além disso, o maior influxo e acúmulo de P na planta quando utilizado 450 mg dm-3, incrementou a concentração dos pigmentos fotossintéticos e elevou a capacidade fotossintética das mudas de C. trichotoma. O maior aproveitamento da energia luminosa pelo fotossistema II (Fv/Fm = 0,76) foi observado nas mudas cultivadas com 450 mg dm-3 de P, com aumento de 95% quando comparadas às mudas sem adição de P. Assim, percebemos que essa espécie arbórea, é exigente e responsiva em relação ao maior teor de P disponível no solo.

ABSTRACT The application of phosphorus (P) doses in the soil can increase the growth of native tree species of economic and environmental interest, such as Cordia trichotoma. Thus, this research aims to evaluate the morphological and the physiological parameters in C. trichotoma seedlings, cultivated in soil with increased P content. The experiment was conducted under greenhouse conditions in pots with 2.5 dm-3 of soil, four doses of P (0, 150, 300 and 450 mg dm-3), and six replicates. P content in the soil, P concentrations in the leaves, morphological attributes (height, stem diameter, aerial dry matter, root dry matter, and leaf area) and physiological attributes (photosynthetic pigment content and chlorophyll α fluorescence) were determined 180 days after transplantation. The increase in the available P content in the soil allowed greater absorption of this element by the plant’s roots, increasing the concentration in the leaves, and therefore favoring the energetic metabolism of the plants. In addition, the higher influx and accumulation of P in the plant when 450 mg dm-3 was used, increased the concentration of the photosynthetic pigments and increased the photosynthetic capacity of the C. trichotoma seedlings. The highest use of the light energy by photosystem II (Fv/Fm = 0.76) was observed in the seedlings cultivated with 450 mg dm-3 of P, with a 95% increase when compared to seedlings without P. Thus, we observed that this tree species is demanding and responsive to the higher P content available in the soil.

Abstract In forest nurseries, one of the factors that change the growth and quality of seedlings is water supply, which has a direct influence on metabolic processes such as stomatal conductance and photochemical efficiency of photosystem II. This study aims to identify the influence of different watering regimes as well as the use of a water-retaining polymer on the initial growth and metabolic processes of Enterolobium contortisiliquum seedlings. The experimental design was in random blocks with a factorial scheme. Morphological attributes, as well as physiological and biochemical attributes were investigated. We verified that the performance of E. contortisiliquum seedlings depends on the watering regime provided to the plants; furthermore, up to 60 days after the application of the treatments, both the height and diameter of the collection and the leaf water potential were similar in the water regimes of 8 mm day-1 and 12 mm day-1.

Abstract This work aimed to evaluate the influence of the substrate composition on the emergence, vigor, and growth of Tabernaemontana catharinensis seedlings in a greenhouse. Seeds were placed to germinate by testing the following substrates: pure Mecplant and combined with fine texture vermiculite (V) or charcoal rice husk (CRH) in different proportions. Variables of emergence percentage, emergence speed index, height, collection diameter, root length, leaf area, dry mass (shoot, root, and total), Dickson quality index, and photosynthetic pigment contents were evaluated. Germinated plants on pure Mecplant substrate presented lower emergence values and morphophysiological parameters. This commercial substrate associated with vermiculite at 1:1 and 1:3 proportions provided higher seed vigor and higher seedling growth, proving to be more adequate for the seedling formation of the species. The formulated substrates did not show a significant influence on the photosynthetic pigment contents.

ABSTRACT Potato cultivation is widespread around the world, being exposed to several abiotic stresses, including soils with high aluminum (Al) availability. Silicon (Si) is recognized for alleviating the stress caused by Al in various plant species. Thus, the aim of this study was to investigate the potential of Si to mitigate the oxidative stress caused by Al in potato genotypes, exhibiting differential sensitivity toward this element. Plants of the Al-sensitive genotype (SMIJ319-7) and Al-tolerant genotype (SMIF212-3) were grown for two weeks in a hydroponic system with the nutrient solution containing combinations of Al (0 and 1.85 mM) and Si (0, 0.5 and 1.0 mM). At the end of the experiment, photosynthetic parameters, pigment content, root and shoot growth, superoxide dismutase and guaiacol peroxidase activity and lipid peroxidation were evaluated. In both potato genotypes Al inhibited root and shoot growth and decreased all photosynthetic parameters and superoxide dismutase activity. Silicon was able to partially alleviate the damage caused by Al in parameters of root growth in the Al-tolerant genotype while increasing the activity of antioxidant enzymes and mitigating the Al-induced damage to membrane lipids in roots and shoot in both genotypes. The Al-tolerant genotype showed greater water use efficiency and transpiration rate in control conditions as compared to the Al-sensitive genotype. These data indicate that Si application can improve the defense ability of the tested potato genotypes against Al toxicity and that the Al-tolerant genotype is more responsive to Si.

RESUMO Este trabalho foi realizado com o objetivo de verificar a plasticidade dos folíolos de plantas jovens de Cabralea canjerana e sua capacidade de adaptação a diferentes ambientes luminosos por meio de características morfológicas e fisiológicas. Para isto, foram selecionadas 12 plantas de fragmento de Floresta Estacional Decidual secundário, sendo seis crescendo sob dossel e seis a pleno sol. As árvores foram classificadas conforme sua posição sociológica em emergentes e dominadas. As folhas foram classificadas em apicais, intermediárias e basais de acordo com a sua posição na copa. Foram mensuradas as variáveis número total de folhas, largura, comprimento, espessura, área foliar e massa seca dos folíolos; teor de clorofilas a e b e carotenoides. Folíolos de árvores a pleno sol, emergentes e da posição superior da copa, considerados os mais expostos a luminosidade, apresentaram características xeromórficas como redução do tamanho do folíolo, maior espessura do limbo, menor área foliar e menor teor de clorofila b. A semelhança na massa seca e no conteúdo de pigmentos evidenciam que a atividade fotossintética das plantas de C. canjerana analisadas não está sendo prejudicada pelas diferentes condições do ambiente, o que demonstra a plasticidade da espécie e sua capacidade de desenvolvimento em diversas condições de luminosidade.

ABSTRACT This work was carried out to verify the plasticity of saplings of Cabralea canjerana plants and their capacity to adapt to different light environments by means of morphological and physiological characteristics. For this, 12 plants of a secondary Deciduous Seasonal Forest fragment were selected, six growing under canopy and six in full sun. Trees were classified according to their sociological position as emergent and dominated. The leaves were classified as apical, intermediate and basal according to their position in the canopy. The variables measured were: total number of leaves, width, length, thickness, leaf area and dry mass of leaflets; content of chlorophyll a and b and carotenoids. Emergent leaflets of the upper position of the canopy in full sun, which are considered the most exposed to luminosity, presented xeromorphic characteristics such as leaflet size reduction, greater limbus thickness, smaller leaf area and lower content of chlorophyll b. The similarity in the dry mass and pigment content demonstrates that the photosynthetic activity of the C. canjerana plants analyzed is not being affected by the different conditions of the environment, which demonstrates the plasticity of the species and its capacity of development in several light conditions.

ABSTRACT The quantification of the hydric requirement during the production of quality seedlings is of extreme importance and the substrate used is a mediator of this influence. However, few studies are carried out in this context, particularly on native species such as Luehea divaricata, which has great potential for lumber production and the restoration of riparian forests. The aim of this study was to characterize the survival and growth of L. divaricata seedlings in different substrates and under different irrigation schemes. The experimental design used a factorial scheme composed of four formulations of substrate (100T: 100% turf (peat); 80T: 80% peat and 20% carbonized rice husk - CRH; 60T: 60% peat and 40% CRH; 40T: 40% peat and 60% CRH) and six irrigation schemes. Survival, height, stem diameter, aerial dry matter, root and total leaf area, and Dickson Quality Index were evaluated. We observed elevated survival, height, stem diameter, aerial dry matter, and leaf area under an irrigation of 16 mm. day-1 with substrates 100T and 80T. The dry matter and Dickson Quality Index, independent of the irrigation, resulted in greater carbon accumulation. Thus, we concluded that substrates based on peat, mixed with up to 20% CRH, allowed greater seedling growth, facilitating earlier hardening and expedition, under an irrigation scheme of 16 mm.day-1. L. divaricata is a native species that can be considered to have high hydric demand during the seedling production phase.

This study aimed at identifying the most appropriate level of shading for initial growth of Apuleia leiocarpa seedlings, through their survival, morphological and physiological/biochemical parameters. The following treatments were evaluated: 0 (full sun), 18, 50 and 70 % of shading. Survival was assessed at 30 and 360 days after planting and morphological parameters such as height (H), stem diameter (SD) and H/SD ratio were measured bimonthly for a year. Physiological parameters as contents of chlorophyll a, chlorophyll b, chlorophyll a/b ratio, carotenoids, lipid peroxidation, acid phosphatase enzyme activity, initial fluorescence, maximum fluorescence, maximum quantum yield of photosystem II and electron transport rate were estimated at 180 and 360 days after planting. At 30 days after planting (d.a.p) there was no mortality of Apuleia leiocarpa seedlings influence of different levels of shading. In the assessments performed at 180 and 360 d.a.p., there was no significant difference among levels of shading for H and SD. However, high mortality rates were observed at 360 d.a.p., especially in full sun. Morphological and physiological parameters of Apuleia leiocarpa plants showed this species requires shading (18 and 50 %) in their early stages of growth.

El objetivo de este estudio fue identificar la intensidad de sombra más adecuada para el crecimiento inicial de plantas de Apuleia leiocarpa, por medio de la supervivencia y parámetros morfológicos y fisiológicos/bioquímicos. Los tratamientos fueron: 0 (pleno sol); 18, 50 y 70 % de sombra. La supervivencia se evaluó a los 30 y 360 días después del trasplante y los parámetros morfológicos altura (H), diámetro del cuello (DC) y la relación H/DC, bimensualmente durante un año. Los parámetros fisiológicos contenido de clorofila a, clorofila b, relación clorofila a/b, carotenoides, peroxidación lipídica, actividad de la enzima fosfatasa ácida, fluorescencia inicial, fluorescencia máxima, rendimiento cuántico máximo del fotosistema II y la tasa de transporte de electrones fueron estimados a los 180 y 360 días después del trasplante. A los 30 días después de la siembra (d.a.p) no hubo mortalidad de plántulas de Apuleia leiocarpa ni influencia de diferentes niveles de sombreado En las evaluaciones realizadas a 180 y 360 d.a.p. No hubo diferencia significativa entre los niveles de sombreado para H y SD. Los parámetros morfológicos y fisiológicos de las plantas de Apuleia leiocarpa evidencian que la especie necesita sombra (18 y 50 %) en su etapa inicial de crecimiento.

Resumo: O estudo teve como objetivo avaliar a relação entre o teor de lignina no tegumento de sementes de soja com tolerância à deterioração por umidade e ao estresse oxidativo. Foram utilizadas quatro cultivares de soja: CD 208, CD 215, CD 202 e BRS 184, com teores de lignina no tegumento de 4,2; 2,6; 2,0 e 1,7%, respectivamente. As sementes foram submetidas a uma deterioração por umidade através de chuvas simuladas (4 horas), e, posteriormente, secas em estufa (35 °C), por 37 horas, totalizando dois ciclos de umedecimento e secagem. Foram realizados os testes: germinação, envelhecimento acelerado e teste de tetrazólio. Foi medida a atividade das enzimas antioxidantes: Superóxido Dismutase e Guaiacol Peroxidase; e a peroxidação lipídica. As avaliações foram realizadas no delineamento inteiramente casualizado, em esquema fatorial 2x4, com quatro repetições. As cultivares de soja CD 208 e CD 215, com maior teor de lignina no tegumento, são menos suscetíveis ao dano por umidade. As sementes da cultivar CD 208 também apresentaram menor estresse oxidativo, quando submetidas a deterioração por umidade.

Abstract: This study aimed at evaluating the relationship among lignin content in the seed coat of soybean seeds with tolerance to weathering damage and oxidative stress. Four soybean cultivars (CD 208, CD 215, CD 202 and BRS 184), with lignin contents in the seed coat of 4.2, 2.6, 2.0 and 1.7%, respectively, were used. Seeds were subjected to deterioration by moisture, through artificially simulated rains. Pods of all cultivars were subjected to irrigation by constant sprinkling during 4 hours, and then dried in oven, set at 35 °C, for 37 hours; repeating twice such procedure. After these treatments seeds were subjected to tests and then compared to the control. Tests performed were: germination, accelerated aging and tetrazolium test; thereby quantifying the occurrence of damages by weathering damage. The activity of enzymes superoxide dismutase and guaiacol peroxidase was measured; and the lipid peroxidation was assessed. Soybean cultivars CD 208 and CD 215, with higher lignin content in the seed coat, were less susceptible to weathering damage. Seeds of cultivar CD 208 have also presented lower oxidative stress, when subjected to weathering damage stress.

RESUMO O objetivo deste estudo foi avaliar a influência da adição da cama de frango ao solo sobre o crescimento, produção de biomassa, conteúdo de fenóis e flavonoides e atividade antioxidante em folhas de pimenta-rosa. O experimento foi realizado na Universidade Federal da Grande Dourados, em Dourados-MS, de outubro de 2009 a maio de 2010. A pimenta-rosa foi cultivada em fileira simples e dupla com cama de frango incorporada nas doses de 0, 5, 10, 15 e 20 t ha-1. Os tratamentos foram arranjados em fatorial 2 x 5 em blocos casualizados com quatro repetições. Houve uma interação significativa entre doses de cama de frango e épocas de avaliação para altura de plantas e conteúdo de clorofila. Foi observado um aumento linear na área foliar, massa fresca e seca de folhas e diâmetro dos ramos principais com o aumento das doses de cama de frango. As plantas cultivadas em fileira simples apresentaram maior massa fresca de caules com o aumento das doses de cama de frango. A cama de frango nas doses de 15 e 20 t ha-1 promoveu um incremento no conteúdo de fenóis e flavonoides nas folhas. Nenhum efeito significativo na atividade antioxidante foi observado com o método químico utilizando DPPH. Portanto, recomenda-se o cultivo de plantas de pimenta-rosa em fileira dupla e 20 t ha-1 de cama de frango para maior crescimento, produção de biomassa, e conteúdo de fenóis e flavonoides.

ABSTRACT The aim of this study was to evaluate the influence of the addition of poultry litter on growth, biomass yield, flavonoid and phenol content, and antioxidant activity in leaves of pink pepper. The experiment was carried out at the Federal University of Grande Dourados, in Dourados, Mato Grosso do Sul state, from October 2009 to May 2010. Pink pepper was grown in single or double row in soil with incorporated poultry litter at doses of 0, 5, 10, 15 and 20 t ha-1. Treatments were arranged as 2 x 5 factorial in a randomized block design with four replications. There was a significant interaction between the doses of poultry litter and evaluation times for plant height and chlorophyll content. A linear increase in leaf area, fresh and dry weight of leaves and diameter of main stems with increasing doses of poultry litter was observed. Plants grown in single row showed higher fresh weight of stem with increasing doses of poultry litter. Poultry litter at 15 and 20 t ha-1 promoted an increase in flavonoid and phenolic contents in the leaves. No significant effect on the antioxidant activity was observed by the chemical method using DPPH. Therefore, it is recommended the cultivation of pink pepper plants with double row and 20 t ha-1 of poultry litter to higher growth, biomass yield, and flavonoid and phenol content.

RESUMO: O alumínio (Al) é altamente tóxico para as plantas, causando estresse e inibindo o crescimento e o silício (Si) é considerado benéfico para as plantas. Este elemento químico tem uma alta afinidade com o Al. O objetivo deste estudo foi investigar o potencial do Si em amenizar os efeitos tóxicos do Al sobre plantas de batata ( Solanum tuberosum L.) e avaliar se esse comportamento é diferente entre os genótipos com diferente sensibilidade ao Al. Plantas de batata dos genótipos SMIJ319-7 (sensível ao Al) e SMIF212-3 (tolerante ao Al) foram cultivadas por 14 dias em solução nutritiva (sem P e pH 4,5±0,1), sob exposição a combinações de Al (0 e 1,85mM) e Si (0; 0,5 e 1,0mM). Após esse período, parte aérea e raízes dos dois genótipos foram coletadas para determinar o conteúdo de Al nos tecidos e avaliar parâmetros morfológicos das raízes e parte aérea. Raízes de ambos os genótipos acumularam mais Al do que a parte aérea, e o genótipo tolerante ao Al acumulou mais Al do que o sensível, tanto nas raízes quanto na parte aérea. Além disso, a presença de 0,5 e 1,0mM de Si juntamente com Al reduziu o conteúdo de Al na parte aérea em ambos os genótipos e nas raízes do genótipo tolerante ao Al, respectivamente. O Si amenizou os efeitos tóxicos do Al para número de ramificações de raízes e de folhas em ambos os genótipos de batata. Si tem o potencial para amenizar os efeitos tóxicos do Al em plantas de batata, independente da sensibilidade ao Al.

ABSTRACT: Aluminum (Al) is highly toxic to plants, causing stress and inhibiting growth and silicon (Si) is considered beneficial for plants. This chemical element has a high affinity with Al. The aim of this study was to investigate the potential of Si to mitigate the toxic effects of Al on potato ( Solanum tuberosum L.) plants and assess whether this behavior is different among genotypes with differing degrees of sensitivity to Al. Potato plants of the genotypes SMIJ319-7 (Al-sensitive) and SMIF212-3 (Al-tolerant) were grown for fourteen days in nutrient solution (without P and pH 4.5±0.1) under exposure to combinations of Al (0 and 1.85mM) and Si (0, 0.5 and 1.0mM). After this period, shoot and roots of the two genotypes were collected to determine Al content in tissues and assess morphological parameters of root and shoot growth. Roots of both genotypes accumulated more Al than shoots and the Al-tolerant genotype accumulated more Al than the sensitive one, both in roots and in shoot. Furthermore, the presence of 0.5 and 1.0mM Si together with Al reduced the Al content in shoot in both genotypes and in roots of the Al-tolerant genotype, respectively. Si ameliorated the toxic effects of Al with regard to number of root branches and leaf number in both potato genotypes. Si has the potential to mitigate the toxic effects of Al in potato plants regardless of Al sensitivity.

RESUMO O presente trabalho teve como objetivo geral caracterizar a influência do solo e da topografia no componente arbóreo de fragmentos, no entorno do Reservatório Divisa, na região dos Campos de Cima da Serra, Sul do Brasil. O levantamento da vegetação foi realizado em quatro fragmentos, sendo em cada parcela (10 x 20 m) efetuada a identificação e medição da circunferência à altura do peito (CAP) dos indivíduos com CAP ≥ 30 cm. Os dados de vegetação foram submetidos à análise de agrupamento. Adicionalmente, foram obtidas as variáveis ambientais, como declividade média das parcelas e amostras de solo, na camada de 0-20 cm de profundidade. A correlação entre os dados ambientais e de vegetação foi realizada por meio da Análise de Correspondência Canônica. As características físicas do solo não apresentaram influência nos grupos formados e nas espécies. Nos capões, a constante presença do gado influenciou negativamente a estrutura do sub-bosque, assim como as características químicas do solo. Alumínio e saturação por alumínio apresentaram maior influência nas espécies predominantes da mata ciliar enquanto cobre e enxofre influenciaram as espécies presentes nos capões. Espécies como Araucaria angustifolia, Eugenia uruguayensis, Blepharocalyx salicifolius, Calyptranthes concinna, Lithraea brasiliensis, Myrsine coriacea, Ocotea pulchella e Sebastiania commersoniana são adaptadas à mata ciliar, podendo ser utilizadas na recuperação e enriquecimento desses ambientes.

ABSTRACT This study aimed to characterize the influence of the soil and topography in the tree component of the fragments, in around the Divisa Reservoir, in the region of the Campos de Cima da Serra, Southern Brazil. The vegetation survey was conducted in four fragments, with each plot (10 x 20 m) performed the identification and measurement of the circumference at breast height (CAP) of subjects with CAP ≥ 30 cm. The vegetation data were subjected to cluster analysis. In addition, environmental variables were obtained as an average slope of plots and soil samples at 0-20 cm depth. The correlation between vegetation data and environmental data was performed by means of Canonical Correspondence Analysis. The soil physical characteristics showed no influence on the groups formed and species. In the geldings, the constant presence of cattle influenced negatively the structure of the understory, as well as the chemical characteristics of the soil. Aluminium and aluminum saturation have higher influenced on the predominant species of riparian vegetation as influenced copper and sulfur species present in geldings. Species such as Araucaria angustifolia, Eugenia uruguayensis, Blepharocalyx salicifolius, Calyptranthes concinna, Lithraea brasiliensis, Myrsine coriacea, Ocotea pulchella and Sebastiania commersoniana are adapted to riparian and can be used in the recovery and enrichment of these environments.