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Invasões biológicas e as monodominâncias de espécies vegetais podem alterar as propriedades físico-químicas e biológicas do solo, afetando a sua microbiota, que é um importante indicador da sanidade desse ambiente. A aroeira (Myracrodruon urundeuva) é uma espécie arbórea que ocorre em monodominâncias na região do Médio Rio Doce (Minas Gerais), e sua elevada densidade vem acarretando sérios problemas socioambientais. Grandes áreas do município de Tumiritinga-MG estão tomadas por aroeirais e são visualmente perceptíveis diferenças entre o solo das áreas monodominadas por aroeiras e solos sob vegetação nativa. Para investigar se as altas densidades dessas árvores estão causando alterações nas propriedades biológicas do solo sob elas, as comunidades de bactérias, fungos e actinomicetos foram avaliados e raízes de aroeiras foram investigadas a procura de infecções por Fungos Micorrízicos Arbusculares (FMA). Foi constatado que solos sob monodominância das aroeiras são microbiologicamente mais pobres, havendo menor densidade de bactérias, fungos e actinomicetos do que nos solos sob a mata. Também foram encontrados esporos de FMA nos solos dos aroeirais, mas não foram encontradas raízes de aroeira colonizadas por esses fungos. Para avaliar a infectividade desses esporos, substratos estéreis foram inoculados com esporos provenientes dos aroeirais, onde foram colocadas plantas teste para crescer. Decorrido o tempo experimental, não houve colonizações das raízes dessas plantas por FMA. Os resultados obtidos permitiram concluir que a alta abundância da aroeira está afetando negativamente a microbiota do solo, o que pode estar favorecendo o estabelecimento das aroeiras em detrimento de outras espécies, por um efeito de feed-back positivo.

Background: Herbivores cause biochemical, physiological, and morphological changes on plants. The ultimate effects of the herbivore activities are damages on the plant's body that can lead from local tissues death to the plant death. The intensity of herbivore attack and the plant's capability to defend itself determine the outcomes of herbivory. When the plant under attack has economic importance, such damages can diminish the productivity of the plantation and compromise the economy of families and the local communities. Although the adverse effects of herbivory on plants and economy are entirely known, some biological mechanisms underlying these damages remain unclear, especially at the anatomical and hormonal levels. The psyllid Triozoida limbata (Hemiptera: Triozidae) is a critical guava (Psidium guajava) pest in the Neotropical region, causing productivity plantation losses up to 55%. Psyllids cause visible morphological changes on guava leaves; however, there is a lack of detailed studied of the cellular, anatomical, and hormonal aspects of the subject. Thus, this work aimed to determine the alterations caused in guava leaves by T. limbata through anatomical and hormonal analyzes. Results: We found that the psyllid's nymphs feeding causes cells hypertrophy and hyperplasia determining the formation of the leaf-roll galls. Although there was no anatomical differentiation of the mesophilic tissues, the cells accumulate starch. Along with the anatomical changes, we observed increasing in the jasmonic acid and reduction of zeatin concentrations in the leaves. Conclusions: The alteration of phytohormone contents and the anatomical changes indicates that the feeding of T. limbata activates plant defenses, but it is not active toward the insects off. The insect nymphs live inside the leaf-roll galls until adults' phase, feeding on the guava leaves xylem and phloem. In commercial guava orchard, the control of T. limbata nymphs have been difficult. Thus, the understanding of the composition of this protective layer can help to find the most effective and efficient control solution for this pest.

Drought is the major abiotic stress which contributes to the reduction in the productivity of soybeans in Brazil, especially in the savanna regions. Two parental genotypes contrasting in drought tolerance (Embrapa 48–tolerant and BR 16–sensitive) were used to study the molecular mechanism underlying this process in soybeans. The hydric potential of the BR 16 reached values of −1.0 and −1.5 MPa, three days before the Embrapa 48, confirming the contrasting drought tolerance. The proteomic, phosphoproteomic and metabolomic profiles were evaluated to detect the metabolic pathways, which were affected by the drought stress. An integrative overview showed that the tolerant plants maintain cell homeostasis and the photosynthetic metabolism was unchanged under the stress condition in contrast to the sensitive genotype that showed several dysregulated pathways. These findings were confirmed by the protein expression and protein regulation by phosphorylation. Furthermore, just small deviations in the metabolic pathways were observed for drought-tolerant plants in comparison to the sensitive genotype. Complex post-translational modification patterns by phosphorylation were detected in some key enzymes, such as carbonic anhydrase, rubisco activase, transketolase and RNA binding proteins during water deficiency. Osmoprotection does not appear to be the major mechanism for tolerance, as indicated by the accumulation of the metabolite and the phytohormone profiles from tolerant and sensitive soybean plants. Thus, regulatory cascades of the metabolic activities, mediated by protein phosphorylation, may cause a higher water use efficiency in the leaves as well as the translocation from the root to the shoot system.

http://dx.doi.org/10.5902/1980509819605O objetivo do presente estudo foi avaliar o comportamento do fogo em um trecho de Floresta Estacional Semidecídua, usando as variáveis: intensidade do fogo, tempo de queima, material combustível, poder calorífico e calor liberado por área. Foram instaladas 10 parcelas de 5 x 5 m interdistantes em 1 m, perfazendo um total de 250 m2, em um fragmento denominado “Reserva da Biologia”, pertencente à Universidade Federal de Viçosa, Minas Gerais, (20º35’-28º50’S e 42º45’-43º00’W) onde foi realizada a queima controlada utilizando a técnica do fogo a favor do vento, obedecendo ao sentido do aclive. Determinou-se a quantidade de matéria seca, velocidade de propagação do fogo, intensidade, calor liberado e poder calorífico. O tempo de duração da queima variou entre as parcelas de 3’30” a 9’18”. A velocidade do vento, temperatura e umidade relativa do ar no dia da queima permaneceram constantes em todas as parcelas, apresentando valores de 3,5 m s-1 Norte, 20ºC e 79%, respectivamente. Os parâmetros do comportamento do fogo variaram entre as parcelas em: 0,32 a 1,10 kg m-2 para materialcombustível, 11,94 a 75,79 Kcal s-1 m-1 para a intensidade de queima e 1111 a 3789 Kcal m-2 para o calor liberado por área. Os valores médios para velocidade de propagação e poder calorífico foram 0,017 m s-1 e 4411 Kcal Kg-1, respectivamente. As condições climáticas de Viçosa em 2005 foram atípicas em relação aos outros anos, não apresentando nenhum mês seco. Esta condição interferiu nos parâmetros do comportamento do fogo, fazendo com que a queima fosse classificada como de baixa intensidade.

The waterlogging of commonly non-flooded soils acts as a filtering for plant communities. River impoundments can flood a large area never flooded before, changing the local conditions and affecting seeds and growing plants. Therefore, the recruitment process in the regenerating community on these new formed margins may be inhibited. Lists containing plant species indicated for restoration of periodically flooded habitats have been published but the germination and initial development behavior of these species are poorly known. We hypothesize that species indicated to restore flooded habitats (FH) are faster to germinate and their seedling also develop better than species from non-flooded habitats (NH) under waterlogging conditions. Seeds of species from flooded and non-flooded habitats were submitted to treatments of flooding (F) and non-flooding (N) for 90 days, and germination was daily registered. Seedlings of Psidium guajava and Handroanthus serratifolius were submitted to flooding and morphophysiological parameters were measured. Species from both groups had similar patterns of germination, and for most species flooding led to a faster germination. In general, the number of germinated seeds was smaller under flooding. P. guajava seedlings presented decreasing growth and photosynthesis under flooding and H. serratifolius seedlings presented chlorosis, foliar abscission, negative net photosynthetic rate, and root-rotting. Flooding was harmful for plants of both groups, but was worse for seeds and seedlings from NH species. The outcomes show that the use of plant species in restoration programs of dams and reservoir margins must take into account if it will be used seeds or seedlings, since the success and sustainability of this action will depend on the fast and well development of the plants.

RESUMO Este estudo foi realizado no fragmento "Reserva da Biologia", situado na Universidade Federal de Viçosa, Minas Gerais, (20º35'-28º50'S e 42º45'-43º00'W) onde foram instaladas 10 parcelas de 5 x 5 m interdistantes em 1 m. Foi realizada uma queima controlada nas parcelas instaladas, utilizando a técnica do fogo a favor do vento, obedecendo ao sentido do aclive. O objetivo foi caracterizar o banco de sementes do solo antes e depois do fogo, para verificar os efeitos desse distúrbio na densidade das populações e na composição florística da comunidade vegetal. No centro de cada parcela foi coletada uma amostra de solo de 40 x 25 cm, a partir da superfície da serapilheira até 5 cm de profundidade. Um dia após a coleta das amostras de solos as parcelas foram submetidas à queima controlada. Imediatamente após a queima foram realizadas novas coletas de solo seguindo a mesma metodologia adotada anteriormente. Foram obtidas 528 e 429 sementes germinadas das amostras do banco de sementes do solo antes e após o fogo, respectivamente, pertencentes a 23 espécies de 14 famílias botânicas, sendo as mais representativas Melastomataceae, Asteraceae e Urticaceae. Entre as duas amostragens (antes e após o fogo) não houve redução significativa da riqueza de espécies e a similaridade florística foi de 34 %. Miconia cinnamomifolia e Leandra purpurascens foram as espécies mais abundantes nas duas amostragens. As espécies pioneiras se destacaram com 44 e 40 % das espécies presentes no banco de sementes antes e após o fogo, respectivamente. ABSTRACT This study was carried out in a fragment called "Reserva da Biologia", which belongs to the Universidade Federal de Viçosa, in Minas Gerais State, Brazil (20º35'-28º50'S e 42º45'-43º00'W), where 10 plots of 5 x 5 m plots, 1m away from each other, were set up. A controlled burning was performed on the plots, following the wind-driven fire technique, according to the slope orientation. The objective was to characterize the soil seed of the tree community before and after fire, in order to verify the effects of such discontinuance on both population density and floristic composition. In the centre of each plot, one 40 x 25 cm soil sampling was collected, from the leaf litter downward 5cm deep. One day after the soil sampling the plots underwent controlled burning. New soil samplings were done immediately after burning, following the previous methodology. It was counted 528 and 429 seedlings emerging from the soil seed bank before and after the fire, respectively. Such plants were of 23 species and 14 botanical families, from which Melastomataceae, Asteraceae and Urticaceae stood out. There was no meaningful reduction in the species richness or in the density of individuals of the populations between both samplings. The floristic similarity was 34 %. Miconiacinnamomifolia and Leandra purpurascens were the most frequent/abundant species. Pioneer species stood out making up 44 and 40 % of the species found in the area before and after fire, respectively.

The area of the stdy is located in the municipality of vicosa, Minas Gerais State, Brazil, in the geographical coordinates 20 46’ 30.2’’S and 42 52’ 18.4’’W. The objective of this work was to determine the phytosociologic structure and the ecologic groups of the arboreous vegetation of a fragment of Montane Semideciduous Seasonal Forest called “Mata da Agronomia”. For the phytosociologic study the quarter-point-centered method was used. The species sampled were classified acconding to their ecologic group (pioneers, initial secondaries, late secondaries and indifferent). The diversity index found was of 3,728. The greatest Importance Value was represented by Piptadenia gonoacantha with 20,76%, followed by Vernonia diffusa with 8,12% and Anadenanthera colubrina with 5,43%. The family Fabaceae showed the greatest Importance Value with 39,43% followed by Asteraceae with 10,08% and Euphorbiaceae with 3,81%. Among the ecologic groups, taking into account the Importance Value, the pioneers totalized 51,97% followed by the initial secondaries with 39,93%, late secondaries with 5,58%, indifferents with 0,79%, and the non identified with 0,79%. The presence of pioneers with a high Importance Value and low values for the late secondaries allow the conclusion that the area is in a medium secondary succession stadium.

The outcome of plant-mediated interactions among herbivores from several feeding guilds has been studied intensively. However, our understanding on the effects of nematode root herbivory on leaf miner oviposition behavior and performance remain limited. In this study, we evaluated whether Meloidogyne incognita root herbivory affects Tuta absoluta oviposition preference on Solanum lycopersicum plants and the development of the resulting offspring. To investigate the M. incognita-herbivory induced plant systemic responses that might explain the observed biological effects, we measured photosynthetic rates, leaf trypsin protease inhibitor activities, and analyzed the profile of volatiles emitted by the leaves of root-infested and non-infested plants. We found that T. absoluta females avoided laying eggs on the leaves of root-infested plants, and that root infestation negatively affected the pupation process of T. absoluta. These effects were accompanied by a strong suppression of leaf volatile emissions, a decrease in photosynthetic rates, and an increase in the activity of leaf trypsin protease inhibitors. Our study reveals that root attack by nematodes can shape leaf physiology, and thereby increases plant resistance.

This study aimed to recognized the preferential location of species of the tree sinusiae in response to a moisture gradient in Pantanal Matogrossense, Brazil. We established sampling plots of arboreal sinusiae along a soil moisture and flood gradient. Piezometers were installed, allowing monthly measurements of water table depth and flood height during one year. Detrended Correspondence Analysis, Gradient Direct Analysis, Multi-response Permutation Procedures and Indicator Species Analysis were performed to evaluate the effect of moisture gradient on tree distribution. The annual variation of water table is shallower and similar in Seasonally Flooded Forest and Termite Savanna, with increasing depths in Open Savanna, Savanna Forest and Dry Forest. Circa 64% of the species were characterized as having a preferential location in "terrestrial habitats normally not subjected to inundation", while 8% preferentially occur in "wet habitats". Lowest tree richness in flood-affected vegetation types is related to both present-day high climatic seasonality and Late Pleistocene dry paleoclimates in the Pantanal wetland. The tree distribution across different formations in the Pantanal shows a direct relationship with soil moisture gradient. RESUMO O objetivo deste estudo foi conhecer a localização preferencial de espécies da sinúsia arbórea em resposta ao gradiente de umidade no Pantanal Matogrossense, Brasil. Foram estabelecidas parcelas para amostragem da sinúsia arbórea ao longo dos gradiente de umidade do solo e de inundação. Piezômetros foram instalados permitindo medições mensais da profundidade do lençol freático e da altura da lâmina de inundação durante um ano. Análise de Correspondência Destendenciada, Análise Direta de Gradientes, Procedimento de Permutação Multi-resposta e Análise de Espécies Indicadoras foram realizadas para avaliar o efeito do gradiente de umidade sobre a distribuição das plantas. A oscilação do lençol freático é mais superficial e similar na Floresta Sazonalmente Inundada e nos Campos de Murundus, com acréscimo da profundidade no Cerrado no Cerradão e nas Florestas Secas. Cerca de 64% das espécies foram caracterizadas como de localização preferencial em "habitats terrestres normalmente não sujeitos a inundação", enquanto 8% ocorrem preferencialmente em "habitats inundáveis". A baixa riqueza de espécies arbóreas em tipos vegetacionais sujeitos a inundação está relacionada à alta sazonalidade climática atual e aos paleoclimas secos do Pleistoceno Superior no Pantanal. A composição de espécies arbóreas ao longo das diferentes formações no Pantanal apresenta uma relação direta com o gradiente de umidade no solo estudado.

As sementes no solo desempenham o importante papel de promover a regeneração da vegetação e a conservação da biodiversidade local, mas, a despeito dessa importância, estão sujeitas a fatores bióticos e abióticos que podem inibir sua germinação, entre eles efeitos alelopáticos desencadeados pelas plantas que estão presentes no ambiente do solo. Neste trabalho foi testada a hipótese de que a germinação das sementes presentes no banco do solo sob vegetação de Floresta Estacional Semidecidual (FES) é inibida sob o dossel de espécies arbóreas exóticas. Foram coletadas 50 amostras simples de 0,25 x 0,25 x 0,05 m do solo em um fragmento de FES, que foram homogeneizadas, constituindo amostra composta. Desta, foram retiradas amostras que foram submetidas a quatro tratamentos: depositadas em casa de vegetação (SMN-CV); devolvidas ao fragmento de mata (SMN-MN); depositadas sob dossel homogêneo de Pinus elliottii (SMN-P); e alocadas sob plantio homogêneo de Eucalyptus sp. (SMN-E). Foram coletadas, também, amostras de solo sob dossel de P. elliotti (SP-CV) e de Eucalyptus sp. (SE-CV), que foram transferidas para casa de vegetação. A cada 15 dias, o número de plantas foi contado em cada amostra e as plantas obtidas, identificadas quando possível. Foram obtidas, ao todo, 515 plantas de 15 famílias botânicas, 21 gêneros e 13 morfoespécies. A análise de variância dos dados e a comparação das médias pelo teste de Tukey-Kramer a 0,01% evidenciaram que não existem diferenças estatisticamente significativas entre o número de plantas obtidas em cada local. Esses resultados indicam que a baixa densidade e diversidade de plantas frequentemente verificadas no subosque de P. elliotti e Eucalyptus sp. não estão diretamente relacionadas com efeitos supressores promovidos pela presença dessas espécies, suportando dados recentes da literatura que apontam os plantios florestais de espécies exóticas como possíveis áreas de conservação da biodiversidade, em oposição à alcunha de "desertos verdes" que lhe são atribuídos. The seeds in the soil play an important role in promoting the plant regeneration and acts on the local biodiversity conservation, but despite their importance, they are subject to biotic and abiotic factors that may inhibit their germination, including allelopathic effects triggered by the plants that are present in the soil environment. In this study we tested the hypothesis that the germination of seeds of seedbeds from Semidecidual Seasonal Forest (SSF) is inhibited under the canopy of exotic trees. Fifty (50) single samples of soil were collected (0.25 x 0.25 x 0.05 m) in a fragment of SSF; the samples were homogenized and from that new samples were taken and submitted to four (4) treatments: 10 samples were deposited in the greenhouse (SMN-CV); other 10 were returned to the forest fragment understory (SMN-MN); 10 were deposited on the soil under homogeneous canopy of Pinus elliottii (SMN-P) and the last 10 samples were allocated under homogeneous plantation of Eucalyptus sp (SMN-E).We also collected samples of soil under the canopies of P. elliottii (SP-CV) and Eucalyptus sp.(SE-CV) that were transferred to a greenhouse. The number of seedlings was counted at intervals of 15 days in each seedbed sample and the plants obtained were identified when possible. We obtained 515 plants from 15 botanical families, 21 genera and 13 morphospecies. The analysis of variance and comparison of means by Tukey-Kramer 0.01% showed no statistical differences between the treatements. Outcomes indicate that the low density and diversity of plants in P. elliottii and Eucalyptus sp understory are not directly corelated to suppressive effects promoted by the presence of these species, supporting recent data from literature that stands out the forest plantations of exotic species as possible areas for biodiversity conservation, in opposition to the designation of "green deserts" that are assigned to them.

O objetivo do presente estudo foi avaliar o comportamento do fogo em um trecho de Floresta Estacional Semidecídua, usando as variáveis: intensidade do fogo, tempo de queima, material combustível, poder calorífico e calor liberado por área. Foram instaladas 10 parcelas de 5 x 5 m interdistantes em 1 m, perfazendo um total de 250 m2, em um fragmento denominado "Reserva da Biologia", pertencente à Universidade Federal de Viçosa, Minas Gerais, (20º35'-28º50'S e 42º45'-43º00'W) onde foi realizada a queima controlada utilizando a técnica do fogo a favor do vento, obedecendo ao sentido do aclive. Determinou-se a quantidade de matéria seca, velocidade de propagação do fogo, intensidade, calor liberado e poder calorífico. O tempo de duração da queima variou entre as parcelas de 3'30" a 9'18". A velocidade do vento, temperatura e umidade relativa do ar no dia da queima permaneceram constantes em todas as parcelas, apresentando valores de 3,5 m s-1 Norte, 20ºC e 79%, respectivamente. Os parâmetros do comportamento do fogo variaram entre as parcelas em: 0,32 a 1,10 kg m-2 para material combustível, 11,94 a 75,79 Kcal s-1m-1 para a intensidade de queima e 1111 a 3789 Kcal m-2 para o calor liberado por área. Os valores médios para velocidade de propagação e poder calorífico foram 0,017 m s-1 e 4411 Kcal Kg-1, respectivamente. As condições climáticas de Viçosa em 2005 foram atípicas em relação aos outros anos, não apresentando nenhum mês seco. Esta condição interferiu nos parâmetros do comportamento do fogo, fazendo com que a queima fosse classificada como de baixa intensidade. The purpose of this study was to evaluate the fire behavior on a part of Semideciduous Seasonal Forest, using the variables: fire intensity, burning time, fuel, heat content and heat released. Ten plots of 5 by 5 meters were used , totalizing 250 m2 , and the distance between each plot was 1 meter in a place named “Reserva da Biologia” property of Universidade Federal de Viçosa, Minas Gerais, (20o35’-28o50’S e 42o45’-43o00’W) . In this place a control burning was performed using strip headfire technique, obeying the slope direction. The amount of local dry matter, fire propagation velocity, intensity, heat released and heat content were measured. The time duration of the burning ranged between plots of 3’30 “to 9’18”. Wind velocity, temperature, relative humidity were constant in all plots, with values 3, 5 m s-1 North, 20o C and 79% respectively. The values found for fire behavior variables ranged between plots: from 0, 32 to 1, and 10 Kg m-2 for fuel, from 11, 94 to 75,79 Kcals-1m-1 for burning intensity and from 1111 to 3789 Kcal m-2 for heat released. The average values for rate of spread and heat released were 0,017 m s-1 and 4411 Kcal Kg-1, respectively. In the year 2005, the weather conditions were atypical comparing to another years in Viçosa, witch in every month occurs a certain amount of rain. This fact had interference in the fire behavior parameters, for that reason the burning were classified as low intensity.

This study was carried out in a fragment of a Seasonal Semideciduous Forest, which belongs to the Universidade Federal de Vicosa, Minas Gerais, Brazil (20o35'-28o50'S e 42o45'-43o00'W), where ten 5 x 5m plots, 1m away from each other, were set up. A controlled burning was performed on the plots, following the wind-driven fire technique, according to the slope orientation. The natural regeneration layer was floristically and structurally characterized before and after the fire. The floristic survey was performed on the upper right corner of each plot aided by a 1 x 1m wooden square strung with rubber bands each 10cm, making up a net for mapping the sampled individuals in two distinct periods; before fire treatment and then two years after that. Twenty four species and 12 families were sampled for both inventories. The families with greater species richness were: Rubiaceae (6), Fabaceae (4) e Myrtaceae (4). The floristic similarity found was 35% and the species with higher cover value were: Sorocea bomplandii, Psychothria sessilis, and Anadenanthera macrocarpa. There was no meaningful reduction in the species density between the samplings, the same cannot be considered for the Shannon diversity index. The individuals sampled belonged to shrubby or woody vegetation, with resprouting being the key mechanism for this fragment regeneration. RESUMO - Este estudo foi realizado em um fragmento de Floresta Estacional Semidecidual pertencente a Universidade Federal de Vicosa, Minas Gerais (20o35'-28o50'S e 42o45'-43o00'W), onde foram instaladas 10 parcelas de 5 x 5 m interdistantes 1 m. Realizou-se a queima controlada nas parcelas utilizando a tecnica do fogo a favor do vento e obedecendo ao sentido do aclive do terreno. Caracterizou-se floristica e estruturalmente o estrato de regeneracao natural antes e depois do fogo. O levantamento foi feito no canto superior direito de cada parcela, com o auxilio de um quadro de madeira de 1 x 1 m trancado com elastico em intervalos de 10 cm, formando uma rede para mapeamento dos individuos amostrados em dois periodos distintos: antes do tratamento com o fogo e dois anos apos. Foram amostradas nos dois inventarios 24 especies, pertencentes a 12 familias. As familias com maior riqueza especifica foram: Rubiaceae (6), Fabaceae (4) e Myrtaceae (4). A similaridade floristica foi de 35%, sendo as especies Sorocea bomplandii, Psychothria sessilis e Anadenanthera macrocarpa com maior valor de cobertura. Nao houve reducao significativa na densidade das especies entre as amostragens, mas, sim, no indice de diversidade de Shannon. Os individuos amostrados eram de vegetacao arbustiva e arborea, sendo a rebrota mecanismo-chave na regeneracao do fragmento. Palavras-chave: Ecologia do fogo, Regeneracao pos-fogo e Restauracao ecologica.

(Chuva de sementes em Floresta Estacional Semidecidual no município de Viçosa, MG, Brasil). Este estudo objetivou avaliar a composição florística, a densidade e a freqüência de sementes, em 25 coletores, em um trecho de Floresta Estacional Semidecidual. Além disso, classificar os táxons quanto à forma de vida, às síndromes de dispersão e, nas arbóreas, quanto ao estádio sucessional e verificar a similaridade florística entre as espécies identificadas na chuva de sementes e as espécies arbóreas localizadas nas mesmas parcelas dos coletores. O trabalho foi realizado entre dezembro/2004 a novembro/2006. Foram reconhecidos 43 táxons, sendo que Leguminosae foi representada por 11 espécies. A forma de vida dominante foi arbórea (63,1%), as lianas foram representadas por 28,9% das espécies amostradas, as herbáceas por 5,3% e as arbustivas por 2,6%. A densidade média de sementes no primeiro ano foi de 113,92 sementes.m -2 e no segundo de 2.603,84 sementes.m -2 . Essas diferenças demonstraram heterogeneidade espacial e temporal da chuva de sementes. A similaridade florística encontrada pelo índice de Sørensen entre as espécies da chuva de sementes e as espécies arbóreas do trecho do fragmento estudado foi de 32%, valor considerado baixo (≤ 50%). Esse resultado mostrou que a composição da vegetação arbórea adjacente pouco influenciou na chuva de sementes. (Seed rain in a seasonal semideciduous forest at Viçosa, Minas Gerais State, Brazil). This study aims to evaluate the floristic composition, density and frequency of seeds in 25 traps in a section of seasonal semideciduous forest, as well as classify taxons as to life form, dispersal syndromes, and succession phase of the tree species, and verify floristic similarities between seed rain species and tree species located in the same plots. The work was carried out from December/2004 to November/2006. Forty three taxons were recognized and Leguminosae was represented by 11 species. The dominant life form was arboreal (63.1%), climbers were represented by 28.9% of the sampled species, herbs by 5.3% and shrubs by 2.6%. Mean seed density in the first year was 113.92 seeds.m -2 and 2603.84 seeds.m -2 in the second year. These differences showed spatial and seasonal heterogeneity of the seed rain. Floristic similarity using Sørensen’s index between seed-rain species and tree species from the studied fragment was 32%, a value considered to be low (≤ 50%). This result showed that the adjacent arboreal vegetation composition had little influence on the seed rain.

This study examines how habitat structure affects the home range use of a group of Brachyteles hypoxanthus in the Brigadeiro State Park, Brazil. It has been reported that most of the annual feeding time of woolly spider monkeys is spent eating leaves, but they prefer fruits when available. We hypothesise that the protein-to-fibre ratio (PF; best descriptor of habitat quality for folivorous primates) is a better descriptor of habitat quality and abundance for these primates than the structural attributes of forests (basal area is the best descriptor of habitat quality for frugivorous primates of Africa and Asia). We evaluated plant community structure, successional status, and PF of leaf samples from the dominant tree populations, both within the core and from a non-core area of the home range of our study group. Forest structure was a combination of stem density and basal area of dominant tree populations. The core area had larger trees, a higher forest basal area, and higher stem density than the non-core area. Mean PF did not differ significantly between these sites, although PF was influenced by differences in tree regeneration guilds. Large-bodied monkeys could be favoured by later successional stages of forests because larger trees and denser stems prevent the need for a higher expenditure of energy for locomotion as a consequence of vertical travel when the crowns of trees are disconnected in early successional forests. Forest structure variables (such as basal area of trees) driven by succession influence woolly spider monkey abundance in a fashion similar to frugivorous monkeys of Asia and Africa, and could explain marked differences in ranging behaviour and home range use by B. hypoxanthus.

Submitted by Guilherme Lemeszenski (guilherme@nead.unesp.br) on 2013-08-22T18:57:18Z No. of bitstreams: 1 S0102-33062007000300016.pdf: 80214 bytes, checksum: 48c3f1fa1df48e0fd722ef5e697199f5 (MD5) Made available in DSpace on 2013-08-22T18:57:18Z (GMT). No. of bitstreams: 1 S0102-33062007000300016.pdf: 80214 bytes, checksum: 48c3f1fa1df48e0fd722ef5e697199f5 (MD5) Previous issue date: 2007-09-01 Made available in DSpace on 2013-09-30T19:51:59Z (GMT). No. of bitstreams: 2 S0102-33062007000300016.pdf: 80214 bytes, checksum: 48c3f1fa1df48e0fd722ef5e697199f5 (MD5) S0102-33062007000300016.pdf.txt: 42047 bytes, checksum: 1a5c80331c8cf129a191c1d58f4498a0 (MD5) Previous issue date: 2007-09-01 Submitted by Vitor Silverio Rodrigues (vitorsrodrigues@reitoria.unesp.br) on 2014-05-20T15:13:32Z No. of bitstreams: 2 S0102-33062007000300016.pdf: 80214 bytes, checksum: 48c3f1fa1df48e0fd722ef5e697199f5 (MD5) S0102-33062007000300016.pdf.txt: 42047 bytes, checksum: 1a5c80331c8cf129a191c1d58f4498a0 (MD5) Made available in DSpace on 2014-05-20T15:13:32Z (GMT). No. of bitstreams: 2 S0102-33062007000300016.pdf: 80214 bytes, checksum: 48c3f1fa1df48e0fd722ef5e697199f5 (MD5) S0102-33062007000300016.pdf.txt: 42047 bytes, checksum: 1a5c80331c8cf129a191c1d58f4498a0 (MD5) Previous issue date: 2007-09-01 Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq) Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES) Estudos de alelopatia investigam os efeitos positivos e negativos que metabólitos secundários de plantas, microrganismos ou fungos exercem sobre o desenvolvimento de indivíduos vizinhos. Nesse trabalho foram investigados os efeitos de extratos aquosos de folhas, cascas de tronco e cascas de raízes de canela-sassafrás (Ocotea odorifera (Vell.) Rowher) sobre a germinabilidade das sementes, desenvolvimento do sistema radicular e da parte aérea, teor de clorofila da parte aérea e respiração das células radiculares de plântulas de sorgo (Sorghum bicolor L. Moench cv. Empresa Brasileira de Pesquisa Agropecuária (EMBRAPA) BR 303). Os extratos foram preparados adicionando o material vegetal seco e moído oriundo de cada órgão à água destilada e deionizada na proporção 1:10 (p/v). Após agitação constante por 24 h, as soluções foram decantadas e filtradas através de papel de filtro sob vácuo, constituindo os extratos testados. Os extratos aquosos de cascas de tronco e de raízes causaram inibição do desenvolvimento do sistema radicular das plântulas de sorgo e a sua parte aérea teve o crescimento estimulado pelo extrato de cascas de raízes. Os extratos de folhas e de cascas de tronco induziram aumento da biomassa fresca do sistema radicular e diminuição significativa do teor de clorofila. Todos os extratos causaram efeitos negativos sobre a respiração radicular das plântulas de sorgo. Concluiu-se que metabólitos secundários da canela-sassafrás causaram alterações metabólicas e morfológicas nas plantas de sorgo e que, portanto, a presença de canela-sassafrás no ambiente pode desencadear efeitos similares sobre outras espécies vegetais na sua vizinhança. Allelopathic studies investigate the positive and negative effects of secondary metabolites of plants, microorganisms and fungi on the development of neighboring individuals. In this work, the allelopathic effects of aqueous extracts of leaves, bark and root bark of Brazilian sassafras (Ocotea odorifera (Vell.) Rowher) on seed germination, root and shoot growth, chlorophyll content and respiratory activity of the root cells of sorghum seedlings (Sorghum bicolor (L) Moench cv. Empresa Brasileira de Pesquisa Agropecuária (EMBRAPA) BR 303) were analyzed. The extracts were prepared by adding dried, powdered plant material to distilled non-ionized water at 1:10 (w/v). After continuous agitation for 24 h, these solutions were decanted and vacuum-filtered through filter paper, thus constituting the tested extracts. Bark and root bark aqueous extracts caused root growth inhibition in sorghum seedlings while shoot growth was stimulated by the root bark extract. Leaf and bark extracts induced an increase in wet root biomass and a decrease in chlorophyll content. All extracts caused negative effects on sorghum seedling root cell respiration. We concluded that secondary metabolites from Brazilian sassafras caused metabolic and morphological alterations in the sorghum seedlings and the presence of these plants in the environment can cause similar effects on other neighboring plant species. Universidade Federal de Viçosa (UFV) Departamento de Biologia Vegetal Universidade Federal de Viçosa (UFV) Departamento de Engenharia Florestal Universidade Estadual Paulista Júlio de Mesquita Filho Instituto de Biociências Departamento de Botânica Universidade Estadual Paulista Júlio de Mesquita Filho Instituto de Biociências Departamento de Botânica

O objetivo deste trabalho foi investigar se o consumo de folhas de mudas de eucalipto por insetos herbívoros pode ser influenciado pela condição nutricional a que essas plantas estão submetidas. Para tal, mudas de Eucalyptus grandis W. Hill ex Maiden foram mantidas em soluções nutritivas, constituindo tratamentos diferenciados entre si pela presença e ausência dos macronutrrientes nitrogênio, fósforo e potássio, além da solução completa e da testemunha, sendo este último tratamento constituído somente por água destilada. Após as plantas estarem submetidas às diferentes condições de nutrição por 30 dias, suas folhas foram arrancadas e oferecidas como dieta a lagartas de Eupseudossoma involuta (Lepidoptera - Arctiidae). Decorridas 20 horas do início do período de alimentação, o restante da dieta de folhas foi pesado. Avaliaram-se os parâmetros altura e número de folhas das mudas de E. grandis antes e depois de submetidas aos tratamentos, bem como o peso das folhas antes e depois de serem oferecidas aos insetos. Concluiu-se que houve preferência alimentar das lagartas em função da nutrição com que as plantas de E. grandis eram mantidas. This work aimed at investigating whether the consumption of eucalyptus seedling leaves by a herbivorous insect can be affected by the nutritional condition to which these plants have been submitted. To do so, leaves of Eucalyptus grandis W. Hill ex Maiden seedlings (9 months old) kept for 30 days in several nutrient solutions, were offered to Eupseudossoma involuta (Lepidoptera - Arctiidae) caterpillars. Nutrient solutions differed from each other by the presence/absence of nitrogen, phosphorus and potassium. Control treatments consisted of a complete solution (N, P, K present) and a treatment consisting of distilled water. The following parameters were measured: size and number of E. grandis leaves before and after having submitted to the treatments and leaf weight before and after they were offered to caterpillars. We concluded that the preference of caterpillars is a function of the nutritional conditions where the plants of E. grandis were maintained.