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Seed banking is an essential tool for species conservation. However, two world’s biodiversity hotspots in a megadiverse tropical country have high percentage of short-lived seeds, requiring new strategies for preservation. Information on seed storage behaviour is crucial for conservation, especially on highly impacted biomes. Thus, this study aimed to investigate seed desiccation tolerance/sensitivity in native tree species of two world’s biodiversity hotspots, Atlantic Forest and Cerrado. We assessed seed storage behaviour for 11 species. The tests were conducted immediately after seed collection at 12% and 8–5% of water content followed by 3 months of storage at − 18 °C. In addition, we retrieved data on the literature about water content after dispersal and storage behaviour of seeds for several tree species native from these hotspots. It comprised 79 species from 30 families. From this total, 47.4% of species produced orthodox seeds, 19.2% intermediate, and 33.3% recalcitrant seeds. All species from Lauraceae produced recalcitrant seeds. Most of studied species produce long-lived orthodox seeds; however, a high percentage of species produce sensitive seeds. Species producing short-lived seeds require non-conventional storage methods. Information on seed storage behaviour is fundamental for species management, especially in tropical areas, where the number of recalcitrant species is high. Thus, seed banking and other conservation strategies must be improved to avoid species loss. Technologies to improve storage of recalcitrant seeds are discussed.

The current methodology for comparing the volumetric capacity of containers does not make it possible to differentiate the effects caused by the higher concentration of fertilizers, available by volume of container, from the real effect of the growth space and fertilization. The fertilization compensation aims to correct the effect of the concentration of fertilizers, guaranteeing the same proportion of fertilization in different volumetric capacities of containers, making it possible to be a new methodology for the production of forest seedlings. The methodological proposal was applied to the production of Handroanthus ochraceus seedlings, testing two volumetric capacities, 55 and 115 cm³, of containers, of the tube type and six doses of controlled release fertilizer, namely: 0.19; 0.24; 0.30; 0.40; 0.51, and 0.63 g / tube in a completely randomized design with four replications. The height and diameter of the collection were evaluated biweekly up to 150 days after sowing and the dry matter of the aerial and root parts. The results demonstrate that regardless of the volumetric capacity of the container, the highest doses of fertilizer resulted in greater morphological characteristics. Therefore, the effect responsible for the differential growth between the volumetric capacity of the containers, normally attributed to the greater space available for root development, is actually attributed to the greater availability of nutrients, which the fertilization compensation aims to keep constant. It was concluded that the use of basic fertilization compensation proved to be efficient for comparisons between volumetric container capacities.

Tropical recalcitrant-seeded species, which disperse seeds at different seasons, provide evidence of the role of oxidative metabolism in seed bank dynamics. Our results indicate that CAT may regulate field germination. Oxidative metabolism during viability loss in recalcitrant seeds has been previously documented, but little is known about the role of ROS-scavenging enzymes in soil seed bank dynamics, especially in recalcitrant seeds. To address this, recalcitrant-seeded species were studied, Swartzia langsdorffii and Persea wildenovii. Diaspores were kept on the soil after natural dispersion, to simulate the seed bank, and were assessed for seed water content, viability, germination and changes in catalase (CAT), superoxide dismutase (SOD) and peroxidase (PRX) activity throughout the field experiment. These parameters were tested for correlations with climatic data. S. langsdorffii start to germinate after one month in soil, with an increase after two months, when CAT activity decreased and SOD activity increased. SOD was negatively correlated with CAT, and CAT was negatively correlated with germination. However, SOD and CAT were positively correlated for P. wildenovii, whose seeds did not germinate even after four months in the soil and with high activity of ROS-scavenging enzymes throughout the period in the soil. Seeds of these species remained viable during the period in the soil with no or little changes in seed water content. ROS-scavenging enzymes respond to environmental factors, adjusting their activity to maintain seed viability. P. wildenovii seeds did not germinate in the soil due to the timing of dispersal being at the end of rainy season, when additional water supply is limited; ROS-scavenging enzymes probably play a role in seed protection during this dry period. Relationship between CAT regulation and soil seed bank dynamics is discussed.

This work aims to classify forest seeds native to the Alto Rio Grande region regarding the desiccation tolerance and storage behaviour. Germination and water content tests were performed in seeds of different species. The tests were conducted immediately after seed processing, at 12% and 5% of water content, and at 5% after 3 months of storage in -18°C. Based on the results obtained, seeds were classified into recalcitrant, intermediate and orthodox class. Seeds of Brosimum gaudichaudii, Erythroxylum deciduum, Eugenia pleurantha, Myrcia venulosa, Nectandra megapotamica were classified as recalcitrant (22.7% of all species). Seeds of Aegiphila sellowiana, Aspidosperma parvifolium, Blepharocalyx salicifolius, Casearia lasiophylla, Cassia occidentalis, Dalbergia miscolobium, Diospyros brasiliensis, Diospyros hispida, Ilex brevicuspis, Ilex cerasifolia, Myrocarpus fastigiatus, Senna aversiflora, Senna splendida e Blepharocalyx salicifolius were classified as intermediate (59.1% of all species). Seeds of Miconia albicans, Platycyamus regnellii, Styrax camporum and Piptadenia gonoacantha were classified as orthodox (18.2% of all species).

Candeia [ Eremanthus erythropappus (DC.) MacLeish], a Brazilian tree species, is being threatened by indiscriminate logging because the essential oil present in its wood has economic importance. The aim of this study was to develop a near infrared spectroscopic model for estimating the essential oil content in E. erythropappus wood to select trees with a high amount of essential oil before harvesting them. Essential oil from 103 wood powders was extracted via hydrodistillation. The values were calculated as the ratio between the mass of essential oil extracted and the oven dry mass of wood, and correlated to the NIR spectra recorded from the wood powders. Statistics associated with the predictive models have demonstrated that NIR has the potential to be a fast and feasible method to replace standard procedures for selecting trees with a high essential oil content. The NIR-based predictions in an independent validation set yielded a high correlation ( r = 0.89) with the laboratory-determined values for essential oil content in E. erythropappus wood. This NIR model can be applied to guide wood managers for selecting high-oil-content trees before harvesting them and for developing sustainable strategies for industrial utilisation of Candeia populations.

Diaspore structure has been hypothesised to play a role in seed viability and/or germination of recalcitrant seeds, especially for Swartzia langsdorffii. Thus, this work aims to (i) investigate the in situ contribution of pericarp and aril on seed viability and germination, and (ii) identify morphoanatomical traits of S. langsdorffii diaspores that allow its desiccation-sensitive seeds to remain viable. The role of the pericarp and aril in seed survival and germination was investigated by placing the whole fruit, whole seeds (arillate seed) and bare seeds (without aril) in soil in the forest understorey, assessing germination, emergence, dead, firm and predated seeds, and water content of pericarps, arils and seeds. Correlation analysis was performed between environmental variables and physiological parameters. Histochemical features of diaspores were also investigated. Pericarp water content fell after several months, while the aril maintained its water content. Seeds did not lose water even without the presence of the pericarp and aril. However, presence of the pericarp promoted seed water content, viability and germination long after dispersal. The embryo had a thickened outer periclinal cell wall. Pericarp and aril are not essential to prevent water loss in seeds, but do help to retain seed moisture, favouring viability maintenance and promoting germination during the rainy season. Morphoanatomical features of seeds are suggested as main factors that reduce water loss. Survival of these desiccation-sensitive seeds upon dispersal during the dry season appears to be facilitated by multiple diaspore features that prevent viability loss.

O objetivo deste trabalho foi avaliar a sobrevivência e o crescimento de mudas de Eucalyptus grandis e Eremanthus erythropappus, além de analisar o custo do substrato produzido, em função de diferentes formulações utilizadas. Dessa forma, para cada espécie, foi utilizado um experimento instalado em delineamento inteiramente casualizado (DIC), com as dez formulações de substrato contendo esterco de curral curtido, casca de arroz carbonizada, fibra de coco - estes variando nas proporções de 0, 30, 60 e 90% - e vermiculita média (10%). Ao final do processo de produção, foram quantificados: o percentual de sobrevivência, a altura da parte aérea e o diâmetro do coleto das mudas. Além disso, foi calculado o custo para produzir um metro cúbico de cada um dos dez substratos analisados. Verificou-se que os substratos influenciam significativamente o crescimento de ambas as espécies, sendo que o esterco influenciou de forma negativa no crescimento das mudas de candeia, enquanto, para o eucalipto, influenciou positivamente. O aumento de proporções de esterco diminuiu o custo por metro cúbico de substrato.

Este trabalho teve como objetivo avaliar o efeito do espaçamento, arranjo e composição de grupos ecológicos das mudas plantadas no processo de restauração de margem de reservatório artificial no sudeste do Brasil. As avaliações foram realizadas 12 anos após a implantação do experimento em que cinco modelos de plantios mistos foram testados. Primeiramente, fez-se uma avalição geral do povoamento por meio de levantamentos do estrato arbóreo, regenerante, banco de sementes e de análise química e textural do solo. Em seguida, lançou-se mão dos indicadores de recuperação sobrevivência das árvores plantadas, área basal e densidade da comunidade arbórea, acúmulo de serapilheira sobre o solo e índice de fechamento do dossel para comparar os modelos e checar a influência dos fatores experimentais nestes parâmetros. Como resultado da análise geral, obteve-se que o povoamento encontra-se em situação de baixa diversidade, com regeneração deficiente e banco de sementes dominado majoritariamente por uma espécie arbórea exótica utilizada no plantio e espécies herbáceas invasoras, o que pode comprometer a automanutenção do povoamento no futuro. O fator que mais influenciou os modelos foi a composição de grupos ecológicos com os melhores resultados apresentados pelos modelos em que se usaram ambos os grupos das pioneiras e não pioneiras. Provavelmente, o arranjo e o espaçamento de plantio não tiveram muita influência devido à mortalidade das mudas e à regeneração natural que se desenvolveu até esta idade. Assim, recomenda-se que na implantação de povoamentos para reconstituição de matas ciliares não sejam utilizadas apenas espécies pioneiras e sugere-se que a proporção de 50% de espécies pioneiras e 50% de não pioneiras, com o maior número possível de espécies, seja utilizada em áreas com deficiência da regeneração natural. This work aimed to assess the effect of spacing, arrangement and ecological group composition of planted seedlings on the restoration process of artificial reservoir shores in southeastern Brazil. The assessments were performed 12 years after the settlement of the experiment in which five mixed stand models were tested. First, a general evaluation of the stand was performed when we surveyed the overstory and understory, seed bank and soil for chemical analysis.Then, the restoration indicators survival of planted trees, basal area and density of the tree community, litter accumulated on the soil and canopy closure index were utilized to compare the plantation models and to assess the influence the experimental factors on these parameters. In the general analysis, we found that the studied stand presents low diversity, poor regeneration, and seed bank dominated mostly by one planted exotic tree species and weeds, which may jeopardize the self- maintenance of the stand in the future. The factor that most influenced the models was the ecological group composition with the best performance found for models in which both pioneer and non-pioneer groups were used. Probably, the plantation arrangement and spacing did not have greater influence due to both plant mortality and natural regeneration that has developed to this age. Hence, it is not recommended the use of only pioneer species in the implantation of riparian forest and the proportion of 50% pioneers and 50% non-pioneers using as much species as possible is indicated for areas that might present constraints for the natural regeneration.

Made available in DSpace on 2018-11-27T10:20:23Z (GMT). No. of bitstreams: 0 Previous issue date: 2016-03-01 Fundação de Amparo à Pesquisa do Estado de Minas Gerais (FAPEMIG) Swartzia langsdorffii seeds have recalcitrant characteristics. Nonetheless, dispersal begins in the month with the lowest precipitation in the studied region, which could lead to seed death by desiccation. Therefore, the objectives of this study were: (1) to characterize the physiological behaviour of S. langsdorffii seeds related to their desiccation sensitivity/tolerance; and (2) to assess the morphophysiological characteristics that enable the seeds to remain viable after dispersal. Fruits and seeds were subjected to biometric evaluation and the anatomical and ultrastructural features of the seeds were determined. Field assessments were performed to determine the capacity of the seeds to maintain viability and to verify the relation between seed viability, diaspore water content and environmental variables. Seeds of this species were found to be recalcitrant and showed pores distributed throughout the seed coat, and contained a large number of stomata in the hypocotyl-radicle axis epidermis. Moreover, phenolic compounds were found throughout the radicle region. Seeds remained viable in the soil for up to 7 months after dispersal without a significant decrease in water content, despite the low precipitation and soil water content. Radicle protrusion began 5 months after dispersal and coincided with partial fruit decomposition at the beginning of the rainy season. Thus, the possible microclimate created by the pericarp, with the moisture content of the aril and the soil, the presence of the structures in the axis, such as the pores and stomata, the chemical composition and the morphology of S. langsdorffii seeds could favour maintenance of their viability until the beginning of the rainy season. Univ Fed Lavras, Dept Ciencias Florestais, Lab Sementes Florestais, Caixa Postal 3037, BR-37200000 Lavras, MG, Brazil Univ Fed Minas Gerais, Inst Ciencias Biol, Dept Bot, Lab Fisiol Vegetal, Caixa Postal 486, BR-30161970 Belo Horizonte, MG, Brazil Univ Fed Uberlandia, Inst Ciencias Agr, Caixa Postal 37, BR-38500000 Monte Carmelo, MG, Brazil Univ Estadual Paulista, Fac Ciencias Agron, Lab Sementes, BR-18603970 Botucatu, SP, Brazil Univ Estadual Paulista, Fac Ciencias Agron, Lab Sementes, BR-18603970 Botucatu, SP, Brazil FAPEMIG: CRA APQ 04619-10

O objetivo deste trabalho foi avaliar o efeito do intervalo de tempo entre coleta/preparo e estaqueamento no enraizamento de miniestacas em quatro clones de Eucalyptus urophylla x Eucalyptus grandis. O delineamento experimental utilizado foi o inteiramente casualizado, arranjo bifatorial com parcelas subdivididas, tendo os intervalos de tempo nas parcelas (0, 2 e 4 horas) e clones nas subparcelas (C1, C2, C3 e C4), em três repetições de 192 plantas cada. Avaliou-se o enraizamento e a sobrevivência de miniestacas na saída da casa de vegetação e casa de sombra, a sobrevivência, o crescimento e a qualidade do sistema radicular de mudas aos 50 dias de idade. Em três dos quatro clones estudados, períodos de armazenamento das miniestacas superiores a 2 horas causam redução significativa no percentual de enraizamento e na sobrevivência das mudas aos 50 dias de idade. No entanto, o clone C2 apresenta a máxima eficiência técnica para enraizamento na saída da casa de sombra e para sobrevivência das mudas aos 50 dias, quando suas miniestacas são armazenadas por, respectivamente, 2,3 e 2,5 horas; assim como apresenta maior crescimento em altura, quando armazenadas por 4 horas. Em todos os clones, mudas provenientes de miniestacas armazenadas por 4 horas apresentam qualidade do sistema radicular inferior ao sistema radicular de mudas obtidas a partir de miniestacas com 0 e 2 horas de armazenamento.

Neste estudo, objetivou-se estudar o potencial de enraizamento de estacas lenhosas de 20 espécies florestais nativas. Dois experimentos distintos foram conduzidos. Em ambos, as estacas caulinares apresentavam em média de 15 a 20 cm de comprimento. No primeiro, estacas de nove espécies foram selecionadas em quatro classes de diâmetro, com média de 5,0; 9,0; 14,5 e 24 mm. No segundo, estacas de 20 espécies foram tratadas com ácido indolbutirico (AIB). Cada tratamento foi avaliado em quatro repetições com 10 estacas por parcela arranjadas aleatoriamente. Nos dois ensaios, os propágulos foram estaqueados em tubetes preenchidos com vermiculita e casca de arroz carbonizada na relação 1:1 (v:v). Após 45 dias em casa de vegetação, as porcentagens de enraizamento, número e comprimento de raízes por estaca foram computados. No primeiro experimento, seis apresentaram taxas de enraizamento que variaram de 2 a 88%. Estacas com diâmetro médio de 14,5mm apresentaram melhores resultados em relação ao enraizamento e a qualidade do sistema radicular. Já no segundo, nove espécies enraizaram e o percentual variou de 0,5 a 88%, sendo que não foi verificada influência significativa do tratamento com AIB. The aim of this study was to evaluate the rooting potential of lignified cuttings from 20 native forest species. Two different experiments were conducted and in both cases stem cuttings were about 15 to 20 cm in length. In the first experiment, cuttings from nine species were selected in four diameter classes, 5.0 mm, 9.0 mm, 14.5 mm and 24 mm on average. In the second experiment, cuttings from twenty species were treated with indolebutyric acid (AIB). Each treatment was replicated four times, with 10 randomly arranged cuttings per plot. In both experiments, propagules were placed in seedling tubes containing vermiculite and scorched rice husk at a 1:1 ratio (v:v). They were kept in a greenhouse for 45 days, after this measurements were taken of rooting percentage, number of roots and length of roots per cutting. In the first experiment, six cuttings rooted and rooting rates ranged from 2% to 88%. Best rooting and root system quality results were provided by cuttings 14.5mm in average diameter. As for the second experiment, nine species rooted and rooting percentage ranged from 0.5% to 88%, there being no significant influence of the treatment using AIB.

The aim of this study was to evaluate the rooting potential of lignified cuttings from 20 native forest species. Two different experiments were conducted and in both cases stem cuttings were about 15 to 20 cm in length. In the first experiment, cuttings from nine species were selected in four diameter classes, 5.0 mm, 9.0 mm, 14.5 mm and 24 mm on average. In the second experiment, cuttings from twenty species were treated with indolebutyric acid (AIB). Each treatment was replicated four times, with 10 randomly arranged cuttings per plot. In both experiments, propagules were placed in seedling tubes containing vermiculite and scorched rice husk at a 1:1 ratio (v:v). They were kept in a greenhouse for 45 days, after this measurements were taken of rooting percentage, number of roots and length of roots per cutting. In the first experiment, six cuttings rooted and rooting rates ranged from 2% to 88%. Best rooting and root system quality results were provided by cuttings 14.5mm in average diameter. As for the second experiment, nine species rooted and rooting percentage ranged from 0.5% to 88%, there being no significant influence of the treatment using AIB.

Magnolia ovata seeds have been reported as desiccation sensitive. In order to test if the drying rate would affect the assessment of storage behaviour of these seeds, the effect of different drying rates and storage times on the viability was tested. Seeds were dried over activated silica gel (fast drying) or salt solutions for different periods (slow drying) and stored at -20°C. Partial drying transiently increased the final germination and the germination speed index, but further drying resulted in reduction of these parameters. Drying rate affected the final germination and vigour. Seeds that were slow-dried to 0.10 g H2O  g -1 dw retained high viability when compared with seeds desiccated to the same water content level by the fast drying method, although their vigour was reduced. Only slow-dried seeds could be stored at -20°C for 90 d without reduction of viability. These data suggested that the storage behaviour of seeds of M. ovata seeds should be classified as intermediate.

Submitted by Guilherme Lemeszenski (guilherme@nead.unesp.br) on 2013-08-22T18:41:01Z No. of bitstreams: 1 S1516-89132011000300006.pdf: 458139 bytes, checksum: d82cf0eca855a98a74518800f3b97a82 (MD5) Made available in DSpace on 2013-08-22T18:41:01Z (GMT). No. of bitstreams: 1 S1516-89132011000300006.pdf: 458139 bytes, checksum: d82cf0eca855a98a74518800f3b97a82 (MD5) Previous issue date: 2011-06-01 Made available in DSpace on 2013-09-30T19:27:17Z (GMT). No. of bitstreams: 2 S1516-89132011000300006.pdf: 458139 bytes, checksum: d82cf0eca855a98a74518800f3b97a82 (MD5) S1516-89132011000300006.pdf.txt: 45490 bytes, checksum: 425efcb1747d0f7bcad5e7d00d27dafc (MD5) Previous issue date: 2011-06-01 Submitted by Vitor Silverio Rodrigues (vitorsrodrigues@reitoria.unesp.br) on 2014-05-20T15:07:34Z No. of bitstreams: 2 S1516-89132011000300006.pdf: 458139 bytes, checksum: d82cf0eca855a98a74518800f3b97a82 (MD5) S1516-89132011000300006.pdf.txt: 45490 bytes, checksum: 425efcb1747d0f7bcad5e7d00d27dafc (MD5) Made available in DSpace on 2014-05-20T15:07:34Z (GMT). No. of bitstreams: 2 S1516-89132011000300006.pdf: 458139 bytes, checksum: d82cf0eca855a98a74518800f3b97a82 (MD5) S1516-89132011000300006.pdf.txt: 45490 bytes, checksum: 425efcb1747d0f7bcad5e7d00d27dafc (MD5) Previous issue date: 2011-06-01 Royal Botanic Gardens, Kew, UK Millennium Seed Bank (Kew) Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES) The effect of seed drying and imbibition was studied by differential protein expression using two dimensional gel electrophoresis. After drying to a range of water contents, seeds were germinated to assess the viability. Seeds of Magnolia ovata did not withstand the desiccation down to 0.10 g H2O · g-1 dw. The critical water content below which the desiccation sensitivity became apparent was around 0.18 g H2O · g-1 dw (-26.5 MPa). Total protein was extracted and separated by 2D electrophoresis from fresh seeds (0.28 g H2O · g-1 dw), mild dried seeds (0.25 g H2O · g-1 dw) and seeds at low water content (0.10 g H2O · g-1 dw) before and after imbibition for 10 days. The proteome profile revealed the presence of 588 spots on each silver stained gel, from which 21 showed differential expression, correlated with desiccation and germination, by increased or decreased expression. After MS/MS sequencing, three protein spots produced spectra that matched to a Magnolia salicifolia legumin precursor. Results suggested an involvement of this protein in the events taking place during the drying and subsequent imbibitions of the dried seeds. Universidade Federal de Lavras (UFLA) Departamento de Ciências Florestais Universidade Estadual Paulista Júlio de Mesquita Filho Faculdade de Ciências Agronômicas de Botucatu Royal Botanic Gardens Seed Conservation Department Universidade Estadual Paulista Júlio de Mesquita Filho Faculdade de Ciências Agronômicas de Botucatu

Este trabalho teve como objetivo analisar o crescimento e o vigor de espécies arbóreas e arbustivas plantadas na margem do reservatório da UHE Camargos, em Minas Gerais, e verificar o processo de sucessão secundária em função da distância do reservatório e ao longo da área de plantio. Decorridos 150 meses, foi realizado o inventário das espécies arbóreas, medindo-se todos os indivíduos plantados e os provenientes de regeneração natural com DAP ≥ 5cm. Foram atribuídas notas que variaram de 1,0 a 5,0 para avaliação do vigor das árvores. Para o levantamento da regeneração natural, foram demarcados quatro transecções e estabelecidas três parcelas de 1 x 15 m em cada transecção, orientadas no sentido do declive. Os resultados mostram que algumas espécies pioneiras demonstram sinais de senescência após 13 anos de plantio. Foram identificadas na regeneração natural 55 espécies de 27 famílias. Espécies da família Asteraceae predominaram nas áreas mais alteradas, pois são adaptadas a essas condições. Houve predominância da dispersão zoocórica para as espécies regenerantes. Próximo ao reservatório, foram encontradas as maiores densidades de regeneração, enquanto a maior diversidade e altura média foi encontrada do lado da pastagem.

Background Solanaceae seed morphology and physiology have been widely studied but mainly in domesticated crops. The present study aimed to compare the seed morphology and the physiology of germination of Solanum lycocarpum, an important species native to the Brazilian Cerrado, with two species with endospermic seeds, tomato and coffee. Methods Morphological parameters of fruits and seeds were determined by microscopy. Germination was monitored for 40 d under different temperature regimes. Endosperm digestion and resistance, with endo-beta-mannanase activity and required force to puncture the endosperm cap as respective markers, were measured during germination in water and in abscisic acid. Key Results Fruits of S. lycocarpum contain dormant seeds before natural dispersion. The best germination condition found was a 12-h alternating light/dark and high/low (20/30 degrees C) temperature cycle, which seemed to target properties of the endosperm cap. The endosperm cap contains 7-8 layers of elongated polygonal cells and is predestined to facilitate radicle protrusion. The force required to puncture the endosperm cap decreased in two stages during germination and showed a significant negative correlation with endo-beta-mannanase activity. As a result of the thick endosperm cap, the puncture force was significantly higher in S. lycocarpum than in tomato and coffee. Endo-beta-mannanase activity was detected in the endosperm cap prior to radicle protrusion. Abscisic acid inhibited germination, increase of embryo weight during imbibition, the second stage of weakening of the endosperm cap and of endo-beta-mannanase activity in the endosperm cap. Conclusions The germination mechanism of S. lycocarpum bears resemblance to that of tomato and coffee seeds. However, quantitative differences were observed in embryo pressure potential, endo-beta-mannanase activity and endosperm cap resistance that were related to germination rates across the three species.

The direct sowing to tropical forest restoration can be viable when the ecological and silvicultural aspects of species areknown. This work evaluated the effect of breaking seed dormancy and a physical protector on the initial growth of riparian treespecies. The experiment was carried out in a randomized blocks design, in a factorial (2x2), with four blocks and four plots for eachtreatment. The treatment to break seed dormancy used were: immersion in sulphuric acid for 20 minutes and washing in water for 1hour plus soaking for 24 hours for Trema micrantha; immersion in boiling water (100oC) with following soaking until refreshing for24 hours to Senna multijuga and Senna macranthera and pre-soaking in water for 2 hours for Solanum granuloso-leprosum. Thephysical protector used was a transparent plastic cup (500mL). The breaking seed dormancy used was efficient in laboratory, exceptfor S. macranthera. In field conditions, it was efficient only for S. multijuga and S. macranthera. The physical protector did notpresented any benefit for the studied tree species regarding seedlings emergence and survival, but it provided significant differencesin height and base diameter for S. multijuga and in height for S. macranthera after three months. After 24 months, T. micranthapresented the highest values for height and basal diameter. S. macranthera presented the height relative growth and T. micrantha thehighest basal diameter. The studied species can be recommended for ecological forest restoration, using direct sowing.

Sementes de cinco espécies florestais ocorrentes em matas ciliares da bacia do Rio Grande, no Estado de Minas Gerais, foram classificadas de acordo com a tolerância à dessecação e ao armazenamento, como forma de subsidiar futuros programas de propagação e conservação ex situ. Sementes de Miconia argyrophylla DC. (Melastomastaceae), Allophylus edulis (A. St.-Hil., Cambess. e A. Juss.) Radlk. (Sapindaceae), Ixora warmingii Müll. Arg. (Rubiaceae), Aulomyrcia venulosa DC. (Myrtaceae) e Metrodorea stipularis Mart. (Rutaceae) foram coletadas e levadas ao Laboratório de Sementes Florestais, sendo beneficiadas e submetidas à secagem, armazenamento e avaliação da germinação. Após a classificação fisiológica, verificou-se que M. argyrophylla e M. stipularis possuem sementes do tipo ortodoxas, as quais podem ser armazenadas à baixa temperatura (-20ºC) e com baixo conteúdo de água (

The knowledge of morphological characters of seedlings is very important to laboratory studies, to seedlings production in nursery and to evaluate the natural regeneration, aiding to recognize and identify the species. The objectives of this study were to describe and illustrate the external morphological aspects of seedlings of trema (Trema micrantha (L) Blum.) - ULMACEAE, to taxonomy identifying. The method used was efficient to promote the recognizing of species by external characters, aiding to evaluation in laboratory, identify the species in nursery and to natural regeneration studies. Aspects like germination phaneroctyl and philotaxy modification of first leaves were the most important. O conhecimento dos caracteres morfológicos de plântulas e mudas é de grande importância em trabalhos de laboratório, viveiros de produção de mudas e estudos de avaliação da regeneração natural, facilitando assim, o reconhecimento e a identificação das espécies. Neste sentido, os objetivos deste trabalho foram descrever e ilustrar os aspectos morfológicos externos do desenvolvimento de plântulas e mudas de trema (Trema micrantha (L.) Blum.) – ULMACEAE, para fins de identificação taxonômica. O reconhecimento taxonômico da espécie é possível por meio dos caracteres morfológicos externos, seja a partir da plântula ou da muda. Aspectos como a germinação fanerocotiledonar e a modificação da filotaxia, passando de protófilos opostos para metáfilos alternos são importantes para a identificação da espécie. Londrina

This work studied the physiological answers of Tabebuia impetiginosa seeds to desiccation when dried at climatizedroom (20oC/40%RH) (slow dry) and at oven (38o C) (fast dry). At different times during slow and fast dry samples were taken fordetermination of the physiological quality which was done through the germination test, germination index speed and electricconductivity. The slow drying method reduced the water content from 51.33% to 6.33% in 840 hours of drying, under theses conditionsthe germination percentage was 53% and germination index speed of 1.37. During fast drying there was a faster reduction of the seedwater content to a minimum of 1.87% in 240 hours, under these conditions the seeds had shown germination percentage of 47% andgermination index speed of 1.78. Independently of the drying method used the electric conductivity reached a maximum value up to 37hours and levels off thereafter. The drying methods used were efficient in reducing the water content of the seeds without interfering on seed quality. In addition, the results indicated that ipê-roxo seeds presented orthodox behavior during storage.

The objective of this research was to verify the distribution of the tree and shrubs species along the soil humiditygradient in the punctual headwaters environment localized at the Santa Cruz stream watershed, Lavras, Minas Gerais State, Brazil.To understanding the vegetation it was performed a structural survey of shrubs and trees stratum of three degraded and disturbedheadwaters. In each sampled headwaters it was instaled 4 plots of 50 x10m located above (P1), below (P2), on the right (P3) and onthe left (P4) of the headwaters. The area around of the headwaters was separated in two gradients of species. The first gradientconsisted in species present in the plot P2, following the river bed and in the firsts 10m length of the plots P1, P3 and P4. The secondgradient comprised of species present in the plots P1, P3 and P4 from of the 10m length of each plot. In the structural surveys they wererecorded 1.217 individuals distributed in 110 species, 80 genus and 43 botanical families. It was concluded that the exclusiveness ofthe species in the distinct gradients, the value of density of the contrasty individuals for the species in the gradients and the model ofspatial distribution of the species along the river bed demonstrated the specificity of the environment to the headwaters. The specificitydemands different strategies for conservation and reclamation of the headwaters.

This research verified different methods of pre-conditioning and concentrations of tetrazolium solutions for evaluatingof canafistula seed lot quality. Seeds collected in Lavras-MG- were submitted to the following methods of pre-conditioning: a)scarification and immersion in water of 25oC for 14 hours; and b) immersion in water of 95oC and left in the same water to rest withoutheating for 24 hours at 25oC. The teguments of the seeds were removed and the embryos were immerged in 0.07, 0.1 and 0.3%tetrazolium solution during 150 minutes at 25oC. To verify the reliability of the results through the tetrazolium test, germination test,first counting, index of germination velocity and nursery emergency were done. Scarification and immersion in water of 25oC for 14hours were efficient in pre-conditioning canafistula seeds and 0,1% tetrazolium solution for 150 minutes at 25oC allowed evaluatingseed lots of this species.

The objectives of this study were: (a) to accomplish the physical characterization of the Santa Cruz Stream watershed,and b) to analyze the accomplishment of the environmental legislation in the areas of permanent preservation of the streamlets,springs and hillsides. Topographic maps, satellite data, aerial vertical photos and field surveys were used. The gathered data wereprocessed in a GIS using SPRING. The data base was composed by thematic maps of the drainage network, slope, soil, nativeforest, land use, areas of permanent preservation (APPs) and of conflicting land use. About 50% of the watershed area presentedslope above 12%. The predominant types of soil in the watershed were Latosol. Pasture was the predominant land use (62,41%),representing 84.57% of the conflicting use occurring in the watershed. The total area under conflicting use in the watershed was11.04%. The total area of permanent preservation (17.5%) together with the 20% of the area of legal reserve totalized 37.5%.Yet, the native vegetation occupied only 25.74% of the watershed, demanding reforestation of 11.75% of the area.

Direct seeding method of regeneration in mixed plantation was analyzed. The analyzed species were: Cedrela fissilis Vell., Copaifera langsdorffii Desf., Enterolobium contortisiliquum (Vell.) Morong, Piptadenia gonoacantha (Mart.) Macbr. and Tabebuia serratifolia (Vahl) Nich. The trial analyzed three seeding environments: Trema micrantha under story, planted in 5x2m spacing, aged 5 years and named “under story”, seeding in "full sun light" and “pioneer tree species seeding". Seeding density and the germinative protector use were also analyzed. Germinated seeds number, plants survival and soil temperature and moisture, in and out of the germinative protector, were evaluated. The obtained results indicated that the protector increased germination values and velocity, and plants survival of the 5 species, but were not essential for the forest establishment. The seeding density didn’t affect the analyzed factors. The direct light incidence was the best condition for seed germination and survival. However, the under story condition propitiated germination and survival too. Direct seeding showed good results for the studied species.

Sementes de leguminosas florestais, como canafístula, muitas vezes são alvos de injúrias durante sua extração e processamento, além de apresentarem problemas de má-formação do embrião. Estes danos não são comumente detectados, devido à presença de tegumento espesso e duro que impede a visualização das estruturas internas das sementes. O objetivo deste trabalho foi definir a metodologia e verificar a possibilidade de utilização do teste de raios-X, na avaliação dos danos internos em sementes de canafístula, bem como, verificar o efeito desses danos na germinação das sementes. Sementes de três lotes de canafístula foram expostas a radiação em aparelho de raios-X Faxitron HP modelo 43855A por vários tempos e intensidades. Posteriormente, foram divididas em três categorias, de acordo com a anatomia interna visualizada nas radiografias, em sementes cheias, sementes com pequenos danos e sementes com danos severos. Após tratamento para a quebra da dormência, as sementes das diferentes categorias foram submetidas ao teste de germinação. A morfologia interna de sementes de canafístula pode ser visualizadas, com exposição a raios-X por 60 segundos na intensidade de 25 KVp. Os danos na morfologia interna visualizados em radiografias, classificados como severos (mais de 50% da área do embrião danificada) afetam drasticamente a germinação das sementes, justificando sua remoção para promover a melhoria da qualidade física e fisiológica de lotes de sementes de canafístula. Leguminous seeds are common targets for mechanical injury, many times invisible to the human eye. Because of this, it was found necessary to utilize tests, such as the X-ray test, which makes possible the evaluation of this type of injury. The objectives of this project were: to verify the efficiency of the X-ray tests in relationship with physical damage to canafistula seed, to verify the effect of this damage to germination and also to evaluate the regularity that machine should be used. Seeds collected in Lavras-MG in 1986 and 1998, and Lins-SP in 1998 were utilized. Seeds from three groups were placed in an acrylic support with 100 partitions and exposed to radiation for various amounts of time and intensity, utilizing equipment 43855 A X-Ray System (Faxitron-HP). Four partitions of 100 seeds were used for each group. The seeds were divided into three categories according to their internal anatomy visualized by radiographs in full seeds, seeds with little physical damage and seeds with severe physical damage. Subsequently, seed dormancy was broken and then submitted to germination tests. The results obtained provided that a time of 60 seconds and an intensity of 25 KVp allowed the brighter internal visualization of seeds. Severe internal damage detected by radiographs might effect the germination of canafístula seeds, and its justify the remotion of those seeds to improve the physical and physiological quality of canafístula lots.

O objetivo deste trabalho foi avaliar os efeitos da disponibilidade de P no solo, da micorriza formada por Glomus etunicatum e de Mycoform, um estimulante desta última, no crescimento e competição inicial de seis espécies arbóreas semeadas diretamente. O trabalho foi realizado em casa de vegetação com as espécies Senna macranthera (fedegoso), Guazuma ulmifolia (mutamba), Senna multijuga (cássia-verrugosa), Solanum granuloso-leprosum (gravitinga), Schinus terebenthifolius (aroeira) e Trema micrantha (trema), em solo com níveis de P na solução considerados muito baixo, baixo e alto, com inoculação ou não do fungo micorrízico arbuscular G. etunicatum, além do tratamento G. etunicatum + Mycoform. O crescimento das mudas respondeu à inoculação em P muito baixo e baixo. As mudas apresentaram moderada dependência das micorrizas, não respondendo ao G. etunicatum em P alto. Gravitinga morreu em P muito baixo, mas foi dominante com P baixo e alto. Fedegoso foi dominante com P muito baixo, mostrando-se adaptado à baixa fertilidade. G. etunicatum influenciou a dominância das espécies, auxiliando as menos competitivas e gerando maior equilíbrio. Mycoform influenciou pouco o crescimento, nutrição e competição. O crescimento de espécies pioneiras semeadas diretamente é favorecido pela elevação do P e pelas micorrizas, as quais também favorecem o equilíbrio entre espécies. The objective of this work was to evaluate the effects of soil P availability, mycorrhiza and a mycorrhiza stimulatory product (Mycoform) upon growth and initial competition of six sown woody species, in the greenhouse. The species Senna macranthera, Guazuma ulmifolia, Senna multijuga, Solanum granuloso-leprosum, Schinus terebenthifolius and Trema micrantha were sown together in a soil with very low, low and high levels of P in soil solution combined with inoculation treatments of the arbuscular mycorrhizal fungus Glomus etunicatum, G. etunicatum + Mycoform and a non-inoculated control. Growth response to mycorrhizal inoculation occurred with very low and low phosphorus. The seedlings presented moderate mycorrhizal dependency, because there was no response with high phosphorus. Solanum granuloso-leprosum died with very low P, but was the dominant specie with low and high P, and very responsive to phosphorus. Senna macranthera was dominant only with very low P, indicating that it is quite adapted to low fertility soils. Glomus etunicatum influenced the species dominance, promoting the least competitive species and favoring uniformity in plant growth. Growth, nutrition and competition were little influenced by Mycoform. The growth of pioneer species is favored by increasing P availability and by mycorrhiza which also favores the growth equilibrium between them in mixed and direct seeding on low fertility soil.

Este trabalho teve como objetivo testar a eficiência de diferentes tratamentos para quebra da dormência e desinfestação de sementes de canafístula na realização do teste de germinação. O experimento foi realizado em esquema fatorial com três lotes × cinco tratamentos para quebra da dormência × quatro tratamentos de desinfestação das sementes. As sementes utilizadas foram coletadas nos municípios de Lavras-MG, em 1986 e 1998, e em Lins-SP, em 1998. Os tratamentos para quebra da dormência foram constituídos por escarificação manual com lixa, água quente (a- fervura das sementes por 3 minutos com imersão por 24 horas, fora do aquecimento; e b - imersão das sementes em água quente por 24 horas, fora do aquecimento) e ácido sulfúrico (imersão por 15, 17, 20 e 30 minutos). Para desinfestação das sementes foram testados os tratamentos, utilizando Polyfluanide (0,2% por 30 minutos), Benomyl (0,02% por 1 minuto) e hipoclorito de sódio (2% por 3 minutos). Foram utilizadas quatro repetições de 25 sementes em cada tratamento. O teste de germinação foi instalado sobre areia, na temperatura de 25 ºC, sob luz branca constante. As contagens de germinação (plântulas normais) foram realizadas diariamente. O tratamento de imersão das sementes de canafístula em água quente (95 ºC) e posterior permanência na mesma água por mais 24 horas, fora do aquecimento, é eficiente na promoção da germinação, sendo prático e dispensando o uso de tratamentos de desinfestação. This research was carried out to test the different treatments for dormancy breaking and disinfestation of canafistula seeds. The experiment was carried out using a factorial system with three groups × five treatments of dormancy breaking × four treatments of seed disinfestation. The seeds were collected in Lavras-MG in 1986 and 1998, and in Lins-SP, in 1998. The treatments used for dormancy breaking consisted of manual scarification with sand paper. The treatments used for dormancy breaking consisted of scarification with sand paper, hot water, (a - boiling the seeds for three minutes with immersion for 24 hours away from heat; and b- immersion 24 hours away from heat) and sulfuric acid (immersion for 15, 17, 20 and 30 minutes). For seed disinfestation, the treatments were tested using polyfluanide (0.2% for 30 minutes), Benomyl (0.02% for 1 minute) and sodium hypochlorite (2% for 3 minutes). Four repetitions of 25 seeds were used for each treatment. The germination test was installed in sand, at 25 ºC, with white light. Germination counts of normal seedlings were performed daily. The immersion of canafístula seeds in hot water (95 ºC) and posterior permanence in the same water, away from heat, for another 24 hours is effective in promoting germination, practical and does not need disinfestation treatments.

This research determined physiological maturity indicators in Tabebuiaimpetiginosa seeds. In the period of August 6th until October 6th, eight collections were made in trees located in the Federal University of Lavras – UFLA, Minas Gerais State and in itssurroundings. After collections, water content, dry matter, fruits and seeds color; percentage of radicle emission; normal and abnormal seedlings; deteriorated seeds and germination index(GI) were determined. The results obtained showed that when the fruits started the dehiscencethey present green color with purple points. The seeds showed green-brownish-yellow color.At this point, the water content in the fruit and in the seeds was 69.02% and 50.98%,respectively. The fruit and seeds dry matter were, respectively, 30.98g/100g and 49.02g/100g offresh matter. The percentage of radicle emission was 73%; normal seedlings 53%, abnormalseedlings 20%; deteriorated seeds 27%; and GI 2.29%. The presence of cracks and greenspots with purple points in the fruits and green-brownish-yellow color in the seeds are goodpractical indicators to determine the time of harvesting Tabebuia impetiginosa seeds.

A restauração ecológica do papel fundamental na retomada da integridade dos ecossistemas, a partir do restabelecimento da riqueza das espécies e da estrutura das comunidades vegetais. Assim, caso seja a realização de uma realização de planejamento, uma produção de mudas florestais com alta riqueza específica subsidiado ou sucesso da prática. O objetivo deste estudo foi analisar a riqueza de mudas de espécies florestais nativas potencialmente produzidas em viveiros na Bacia do Rio Grande, sul de Minas Gerais. A análise foi revisada no Catálogo das Árvores Nativas de Minas Gerais, considerando como espécies presentes nos subdomínios fitogeográficos Alto Rio Grande, Mantiqueira Sul, Planalto de Poços de Caldas e Noroeste. Para análise das espécies com potencial de produção nos viveiros da Bacia do Rio Grande, Foram utilizados nos dados do registro nacional de sementes e mudas (RENASEM) de 2013. Foram encontradas 1.251 espécies de ocorrência natural, 102 espécies cadastradas e 49 produtos de consumo, distribuídos em 36 municípios. Apenas cinco séries presentes na lista oficial de espécies ameaçadas de extinção foram cadastradas pelas unidades de produção. A riqueza de espécies florestais cadastradas por produto importado Não RENASEM na região estudada é muito baixa, o que pode comprometer o sucesso dos projetos de restauração ecológica.

The external and internal morphological aspects of fruit and seed and the external aspects of germination process, seedlings and saplings of D. mollis Benth. were studied, these observations being made both in the laboratory and greenhouse. Some aspects observed were that the fruit is indehyscent, seed is albuminous, the germination is epigeous-phanerocotylar, and there was an enlargement of primary and secondary roots. These results can be used to identify the species in taxonomic studies, laboratory and nursery practices as well as in natural regeneration studies. Foram estudados os aspectos morfológicos externos e internos do fruto e da semente, além de aspectos externos do processo germinativo e das fases de plântula e planta jovem de Dimorphandra mollis Benth. O trabalho foi realizado em laboratório e casa de vegetação, sendo observado que os frutos são indeiscentes, as sementes são albuminosas, a germinação é epígea fanerocotiledonar e, na fase de planta jovem, ocorre um espessamento das raízes primária e secundárias. Os resultados apresentados podem ser úteis em estudos taxonômicos, em trabalhos de laboratório e viveiro, bem como para estudos de regeneração natural. São Paulo

Made available in DSpace on 2015-02-02T12:39:25Z (GMT). No. of bitstreams: 0 Previous issue date: 2014-09-01Bitstream added on 2015-02-02T13:08:38Z : No. of bitstreams: 1 S0104-77602014000300018.pdf: 202127 bytes, checksum: 12db96e88b30df9a6cf087376ff30278 (MD5) Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP) Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq) Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES) Objetivou-se, com essa pesquisa, realizar a classificação quanto a tolerância à dessecação e a capacidade de armazenamento de sementes de cinco espécies florestais de matas ciliares da bacia do Alto Rio Grande, no Estado de Minas Gerias. Sementes de Casearia sylvestris Swart (Salicaceae), Qualea grandiflora Mart. (Vochysiaceae), Guarea kunthiana A. Juss. (Meliaceae), Eremanthus incanus Less. (Asteraceae), Protium heptaphyllum March. (Burseraceae) foram coletadas e transportadas ao Laboratório de Sementes Florestais, aonde foram beneficiadas e submetidas a dois tipos de secagem, rápida e lenta. Em seguida, foram armazenadas em freezer ou em câmara fria e avaliadas quanto à viabilidade. Após a classificação fisiológica, verificou-se que sementes de C. sylvestris e E. incanus são ortodoxas. Em contra-partida, sementes de G. kunthiana e P. heptaphyllum foram classificadas como recalcitrantes e Q. grandiflora como intermediárias, pois não toleram a secagem a baixos conteúdos de água. Seeds of five forest species were classified according to their physiological storage behavior. Seeds of Casearia sylvestris Swart (Salicaceae), Qualea grandiflora Mart. (Vochysiaceae), Guarea kunthiana A. Juss. (Meliaceae), Eremanthus incanus Less. (Asteraceae), Protium heptaphyllum March. (Burseraceae) were collected and taken to the laboratory, where they were processed and submitted to both rapid and slow drying, storage and assayed for viability. After physiological classification regarding storage behavior, it was observed that seeds of C. sylvestris and E. incanus presented orthodox behavior. Seeds of G. kunthiana and P. heptaphyllum were classified as recalcitrant and Q. grandiflora as an intermediate, which did not tolerate low moisture content. Universidade Federal dos Vales do Jequitinhonha e Mucuri Universidade Federal de Lavras Universidade Estadual Paulista Júlio de Mesquita Filho Universidade Federal de Viçosa Universidade Federal de São João Del-Rei Universidade Estadual Paulista Júlio de Mesquita Filho

Com o objetivo de se estudar as exigências nutricionais no desenvolvimento inicial de mudas de Peltophorum dubium (Spreng.) Taub., foi realizado um experimento em casa de vegetação. Usou-se como substrato um latossolo vermelho-amarelo com baixa disponibilidade de nutrientes, utilizando-se 10 tratamentos, sob a técnica do elemento faltante. Foram aplicados um tratamento completo (com N, P, K, Ca, Mg, S, B e Zn), outros com omissão de um nutriente por vez (-N, -P, -K, -Ca, -Mg, -S, -B e -Zn) e uma testemunha (solo natural). Foram avaliadas as seguintes características: altura, diâmetro, peso de matéria seca da parte aérea e das raízes, e teor de nutrientes na matéria seca da parte aérea. Concluiu-se que as plantas do angico-amarelo apresentam elevada exigência nutricional; os nutrientes P, N, S e o Ca seguidos pelo Mg, K e pelo B são limitantes ao crescimento das plantas; as omissões de K, Ca e de Mg afetam a absorção de S pelas plantas.

Differences in arbuscular mycorrhizal colonization, mycotrophic growth and response to superphosphate were studied in seedlings of 28 native woody species belonging to different successional groups in woodland fragments in the state of Minas Gerais, Southeastern Brazil. The experiment was carried out in a glasshouse in plastic bags filled with a soil-mix composed of soil+burnt rice shell (6:1 v/v) amended or not with superphosphate (Control, P) and infested or not with a mixture of arbuscular mycorrhizal (AM) fungi Glomus etunicatum Becker and Gerdermann and Gigaspora margarita Becker and Hall (M) and co-application of P and M (MP), with 10 replications per species. Successional groups were represented by 8, 5, 4 and 11 species of pioneers, early secondary, late secondary and climax species, respectively. It was found that dry matter yield of climax species was 6.8-fold higher than the pioneer ones in control treatments. However, pioneers were markedly more responsive to soil-mix treatments than climax ones. Based upon shoot dry matter, overall response for M, P and MP overcontrols was 813, 575 and 1688% for pioneers and 0, 48 and 106% for climax ones. Mycorrhizal effects were much greater in soil-mix with no added P than when superphosphate was added. They were maximum and consistent among pioneers and markedly diminished in climax species in which positive response to M was found in only 27% of the species of this group. AM colonization ranged from 0 to 81% of the root length colonized and it was inversely related to succession and directly related to mycorrhizal response. Growth responses to soil-mix treatments were inversely related to seed weight and to succession. Pioneer species have light seeds, high susceptibility to infection and colonization rate and are responsive to both mycorrhiza and superphosphate, whereas, late successional species are more dependent upon their seed reserves than upon AM and superphosphate for initial growth. However, late successional species may become mycorrhiza-dependent in later growth stages. The Glomalean fungi and soil phosphorus are important factors in light of the forest ecology and reforestation technology in low-fertility soils in the tropics.

Pelo importante papel ecológico que a espécie Eremanthus erythropappus (candeia) desempenha, aliado à crescente demanda pelos produtos obtidos dessa espécie, trabalhos vêm sendo feitos com o intuito de desenvolver sua silvicultura. Dentre os estudos com a espécie, é necessário iniciar o processo de clonagem, em razão da necessidade de melhorar a qualidade dos povoamentos a serem implantados. Portanto, o passo inicial para esse objetivo foi definir uma metodologia para resgate de matrizes e enraizamento de estacas da espécie. Como forma de resgatar as matrizes, 24 árvores de um povoamento de candeia com seis anos de idade foram decepadas a 15, 30, 45 e 60 cm de altura em relação à superfície do solo, sendo que em 12 árvores, procedeu-se ao tratamento de escarificação do solo. A contagem e a coleta de brotos foram executadas aos 65 e 135 dias após a decepa, respectivamente. Das brotações obtidas, foram confeccionados três tipos de estacas: Apical 1, Apical 2 e Basal, que foram tratadas com AIB nas concentrações de 0, 200, 400, 800 ou 1600 mg kg-1 e colocadas para enraizarem em casa de vegetação climatizada. Com base nos resultados, conclui-se que a decepa, independente da altura, seguida da escarificação do solo e o enraizamento das estacas preparadas a partir das brotações coletadas de raízes é um método eficiente para resgate de matrizes e enraizamento de estacas de candeia, sendo que os maiores percentuais de enraizamento foram encontrados para as estacas apicais, não variando em função da concentração de AIB. Due to the important ecological function of Eremanthus erythropappus (candeia) wood, combined with the growing demand for its products, studies are being made to develop its silviculture. Among these studies, it is important and strategic to start with the cloning process due to the need for improvement of the stand quality that are to be planted. The initial step toward this goal was to define a methodology for rescue of stock plants and rooting of the species cuttings. As a way to rescue the stock plants, 24 trees aged six years of a candeia stand were severed at 15, 30, 45 and 60 cm in height above ground. In 12 trees, it was proceeded soil scarification. The counting and harvesting of sprouts were performed 65 and 135 days after cut, respectively. From the shoots obtained, three types of cuttings were prepared: Top 1, Top 2 and Basal, which were treated with IBA at concentrations of 0, 200, 400, 800 or 1600 mg kg-1 and placed in a greenhouse for rooting. Based on the results, it was conclude that cut, independent of the height, followed by soil scarification and the rooting of cuttings prepared from the shoots collected in the roots, is an effective method for rescue of stock plants and rooting of candeia cuttings and the highest percentage of rooting was found in the Top1 cuttings and did not vary in function of AIB concentration.

Genipa americana (Rubiaceae) is important for restoration of riparian forest in the Brazilian Cerrado. The objective was to characterize the mechanism and control of germination of G. americana to support uniform seedling production. Morphology and morphometrics of seeds, embryo and endosperm were assessed by light and scanning electron microscopy during germination. Imbibition and germination curves were generated and over the same time interval endosperm digestion and resistance were measured by puncture force analysis and activity assay of endo-β-mannanase (EBM) in water and in abscisic acid (ABA). The gene encoding for EBM was partially cloned and its expression monitored by quantitative real-time-polymerase chain reaction. Embryos displayed growth prior to radicle protrusion. A two-phase increase in EBM activity coincided with the two stages of weakening of the micropylar endosperm. The second stage also coincided with growth of the embryo prior to radicle protrusion. Enzyme activity was initiated in the micropylar endosperm but spread to the lateral endosperm. ABA completely inhibited germination by inhibiting embryo growth, the second stage of weakening and expression of the EBM gene, but EBM activity was not significantly inhibited. This suggests that a specific isoform of the enzyme is involved in endosperm weakening. EBM may cause a general 'softening' of micropylar endosperm cell walls, allowing the embryo to puncture the endosperm as the driving force of the decrease in puncture force.

Made available in DSpace on 2013-08-12T19:23:22Z (GMT). No. of bitstreams: 0 Previous issue date: 2011-07-01 Made available in DSpace on 2013-09-30T17:45:08Z (GMT). No. of bitstreams: 0 Previous issue date: 2011-07-01 Submitted by Vitor Silverio Rodrigues (vitorsrodrigues@reitoria.unesp.br) on 2014-05-20T13:20:13Z No. of bitstreams: 0 Made available in DSpace on 2014-05-20T13:20:13Z (GMT). No. of bitstreams: 0 Previous issue date: 2011-07-01 Item merged in doublecheck by Felipe Arakaki (fe.arakaki@gmail.com) on 2015-11-20T16:38:58Z Item was identical to item(s): 5461, 113396 at handle(s): http://hdl.handle.net/11449/5586, http://hdl.handle.net/11449/114288 Fundação de Amparo à Pesquisa do Estado de Minas Gerais (FAPEMIG) Conduziu-se este trabalho, com os objetivos de desenvolver métodos de beneficiamento e análise de raios X, e estudar o padrão de embebição de sementes de candeia (Eremanthus incanus). As sementes foram colhidas em 2001 e 2002, respectivamente, em Morro do Pilar e Lavras, beneficiadas e guardadas em câmara fria (5ºC/60%UR) até o início dos experimentos. Para identificar sementes vazias, foi desenvolvido um protocolo utilizando raios X combinando potência de radiação e tempo de exposição. Para a eliminação das sementes vazias foi realizado um experimento utilizando soprador tipo South Dakota, combinando aberturas do aparelho e tempo de ventilação. Os lotes originais e as categorias encontradas pelas radiografias foram testadas por testes de germinação, no qual as sementes foram lavadas em hipoclorito de sódio e distribuídas sobre papel, em gerbox, levadas para germinadores com temperatura alternada 20-30ºC, com 10 horas de luz, por até 15 dias. Foram determinadas as curvas de embebição, nas condições de 30ºC, 20-30ºC/10 horas de luz e 30-20ºC/10 horas de luz. O protocolo de raios X que melhor permitiu a visualização das estruturas internas da semente foi 30Kv por 45 segundos. A separação das sementes no soprador na abertura 3,0 por 30 segundos elevou o número de sementes com embrião para valores superiores a 99%, tendo como consequência, a elevação das taxas de germinação. O padrão de embebição é trifásico e o processo de germinação se completa em 72 horas. Sob temperatura alternada, o crescimento da raiz primária é favorecido. The objective of this work was to develop a methodology for seed processing and X-ray analysis and to study imbibition pattern in seeds of candeia (Eremanthus incanus). Seeds were gathered in 2001 and 2002 in Morro do Pilar and Lavras respectively, processed and stored in a cold chamber (5ºC/60%RH) until the start of experiments. In order to identify unfilled seeds, a protocol was developed for X-ray use combining radiation energy (Kv) and exposure time (seconds). For elimination of unfilled seeds, an experiment was conducted using a South Dakota seed blower whereby different opening settings and ventilation times were combined. Original seed lots and categorized lots following radiograph viewing were tested by germination tests, with seeds being cleansed in sodium hypochlorite and scattered over blotting paper in 'gerboxes' and then taken to germinators with alternating temperatures of 20º-30ºC and 10 hours of light, for up to 15 days. Imbibition curves were determined under the conditions 30ºC, 20º-30ºC/10 hours of light and 30º-20ºC/10 hours of light. The X-ray protocol that best allowed viewing of internal seed structures was 30Kv for 45 seconds. Seed separation using the blower setting at a 3.0 opening for 30 seconds raised the number of embryonic seeds to values exceeding 99%, also raising the germination rates as a consequence. The imbibition pattern is three-phased and the germination process is completed in 72 hours. Under alternate temperatures, primary root growth is favored. Universidade Federal de Lavras Departamento de Ciências Florestais Universidade Estadual Paulista Júlio de Mesquita Filho Departamento de Produção Vegetal Universidade Estadual Paulista Júlio de Mesquita Filho Departamento de Produção Vegetal

Made available in DSpace on 2022-04-28T18:56:44Z (GMT). No. of bitstreams: 0 Previous issue date: 2011-01-01 Seed priming is a treatment to improve seed quality and plant growth upon germination and is applied widely to crop species to improve uniformity and yield. The present study aimed to establish a priming protocol for Solanum lycocarpum St.Hil., to improve germination of the dormant seeds and seedling development for in situ restoration, and to determine the mechanism underlying priming. Priming for 15 d at 15°C in water delivered the optimal priming effect, resulting in the fastest and most uniform germination and a high final germination percentage compared with shorter treatments, higher temperatures and lower water potentials. Seedling development following priming was significantly improved. To determine the role of endosperm weakening during priming, the force required to puncture the endosperm and endo-β-mannanase activity were determined during priming and subsequent germination. Mechanical weakening of the endosperm and development of endo-β-mannanase activity appeared to contribute to the priming effect. Despite the difference in dormancy the mechanism behind priming is similar to that in tomato. Seedling production of S. lycocarpum, e.g. for in situ restoration, would benefit from priming. Universidade Federal de Lavras Departamento de Ciências Florestais Laboratório de Sementes Florestais, CP 3037, 37200-000, Lavras, MG Universidade Estadual Paulista Faculdade de Ciências Agronómicas Departamento de Produçaandtild;o Vegetal, CP 237, 18603-970, Botucatu, SP Royal Botanic Gardens Kew Seed Conservation Department, Wakehurst Place, Ardingly, West Sussex RH17 6TN Universidade Estadual Paulista Faculdade de Ciências Agronómicas Departamento de Produçaandtild;o Vegetal, CP 237, 18603-970, Botucatu, SP

Foi avaliado o processo de regeneração natural de mata em função da distância do rio, da compactação do solo e da distância da fonte de sementes em uma área degradada por uso como área de empréstimo de terra para construção da barragem da UHE Camargos, MG, aos 155 meses após o plantio. Para o levantamento da regeneração natural foram implantadas parcelas de 2 x 15 m a cada 10 m, dentro de três transectos, alocados no sentido do declive, com 15 m de largura e comprimento variável, onde foi identificada e medida a altura de todos os indivíduos com DAP 10cm were identified and measured in height. Sixty four species of 27 families were found. The adjacent fragment provides a great amount of propagules for the natural regeneration, since many regenerative species in the recovering area were found only in the arboreal stratum of that fragment. A distance of up to 75m to the fragment did not affect the regeneration density, height and diversity, but in the plots taken by the grass Mellinis minutiflora, the density was smaller and the plants higher.

A candeia, Eremanthus erythropappus (DC.), é uma espécie florestal com múltiplos usos, como o do seu óleo, que possui propriedades antiflogísticas, dermatológicas e espasmódicas. Por possuir sementes com baixa porcentagem de germinação, o objetivo deste trabalho foi estudar a qualidade dessas sementes, visando conhecer melhor o seu desempenho germinativo. Realizou-se no Laboratório de Sementes Florestais da Universidade Federal de Lavras – UFLA, um experimento utilizando-se sementes originárias de Carrancas, Itabirito, Morro do Pilar, Baependi e Delfim Moreira, aplicando-se o delineamento experimental inteiramente casualizado com quatro repetições de 25 sementes. Realizou-se teste de germinação com temperaturas alternadas de 20–30 °C e fotoperíodos de 10 e 14 horas de luz, ocorrendo a avaliação no 14° dia. As sementes não germinadas foram dissecadas para verificação da presença ou ausência do embrião, sendo divididas em sementes cheias e vazias. Sementes das mesmas progênies submetidas ao teste de germinação passaram por análise de raios X, com a finalidade de melhor visualização das estruturas internas, ou seja, verificar a presença ou não de embrião. Foram selecionadas duas progênies de cada procedência que se destacaram nos testes anteriores (germinação e raios X). Essas sementes passaram por soprador e a fração retida foi submetida à análise de raios X e germinação. Para as características avaliadas, as progênies C6, I18, M24, B9 e D2 se destacaram em qualidade, conforme a germinação e semente vazia. As sementes das progênies C25, I17, M22, B24 e D16 foram as que apresentaram as taxas mais baixas, respectivamente. Após o tratamento com soprador, constatou-se que as progênies atingiram um alto número de sementes cheias, possibilitando um incremento na germinação de 9% para I12 e de 47% para B24. O baixo percentual germinativo pode ter se dado em razão do grande número de sementes sem embrião.