ABSTRACT: Plants use light as a source of energy in the process of photosynthesis. Different levels of luminosity cause physiological and morphological changes in the plant, and its success depends on its adaptation to these different levels. Light emitting diodes (LED) have been proposed as a light source in controlled environments. The present research evaluated physiological and morphological aspects in Eucalyptus benthamii (Myrtaceae) seedlings kept under different colors of LED lamps and submitted to water stress. The experiment was carried out in a completely randomized design, in which the treatments were defined as: T1 (control, with white light); T2 (blue light); T3 (red light) and T4 (mixed blue and red light). Red light resulted in the best response to most morphological variables in plant growth. In response to water stress, blue light LEDs resulted in a better seedling response, with slower reduction of photosynthetic rate and other variables. This may indicate the possibility of reducing water deficit damage in seedlings acclimated to blue light prior to field planting.

RESUMO: As plantas utilizam a luz como fonte de energia no processo de fotossíntese. Diferentes níveis de luminosidade causam mudanças fisiológicas e morfológicas na planta, e o seu sucesso depende da sua adaptação a esses diferentes níveis. Diodos de emissão de luz (LED) têm sido propostos como fonte luminosa para ambientes controlados. O objetivo do presente trabalho foi avaliar aspectos fisiológicos e morfológicos em mudas de Eucalyptus benthamii (Myrtaceae) mantidas sob diferentes cores de lâmpadas LED e submetidas ao estresse hídrico. Foram realizados dois experimentos, sendo que um avaliou o efeito de diferentes cores de LEDs no crescimento das mudas e outro analisou o efeito das luzes na aclimatação das mudas e após exposição a deficit hídrico. O experiment foi conduzido em delineamento inteiramente casualizado, em que os tratamentos foram definidos como T1 (controle, com luz branca); T2 (luz azul); T3 (luz vermelha) e T4 (luz azul e vermelha mista). A luz vermelha resultou em melhor resposta para a maioria das variáveis morfológicas no crescimento das plantas. Emresposta ao estresse hídrico, os LEDs de luz azul resultaram em uma melhor resposta das mudas, reduzindo mais lentamente a taxa fotossintética e demais variáveis. Isso pode indicar a possibilidade de reduzir os danos de deficit hídrico nas mudas aclimatadas com luz azul anteriormente ao plantio a campo.

ABSTRACT When producing Ilex paraguariensis seedlings through vegetative propagation, selecting the correct populations and genotypes, and obtaining juvenile material, may be fundamental for its success. Therefore, this search aimed to test its vegetative propagation through cutting and rescue using detached branches of different populations in Santa Catarina state, Brazil. Thus, two experiments were installed in September 2019 in order to test: I) the cuttings of four populations belonging to the municipalities of Catanduvas (CT), Painel (PL), Três Barras (TB), and Urupema (UR), using ten randomly chosen genotypes from each, and; II) the epicormic sprouting of detached branches from these same populations. Both experiments were carried out in Lages, Santa Catarina. In February 2020, the cutting was evaluated according to the percentages of survival, callus, rooting, new sprouts, and original leaves permanence. The branches were evaluated every 30 days after storing, observing the percentages of sprouting branches, number of sprouts, and length of sprouts in centimeters. As for cutting, there was a low survival percentage in all populations (<15%), but some genotypes presented greater vigor, such as TB1 (46%), TB7, and TB3 (both 28%). Most live cuttings presented calluses (>70%), characteristic of material of high maturity. Rooting was low for populations (<1.5%) and genotypes (<10%). Branches presented sprouts up to 60 days, with TB presenting the highest total number of sprouts (approximately 300) and the greatest average length (2.8 cm). In general, survival and rooting of cuttings were affected by both populations and genotypes, highlighting TB. A similar response was observed for the branches’ sprouting. New studies with more populations, further analyses of the branches’ characteristics, and better storage conditions are recommended.

RESUMO Quando produzidas mudas de Ilex paraguariensis através da propagação vegetativa, a seleção correta das populações, genótipos, e ser capaz de obter material juvenil, são fundamentais para seu sucesso. Assim, o objetivo desta pesquisa foi testar sua propagação vegetativa por estaquia e resgate utilizando galhos destacados de diferentes populações do estado de Santa Catarina, Brasil. Desta forma, dois experimentos foram instalados em setembro de 2019 para testar: I) a estaquia de quatro populações, pertencentes aos municípios de Catanduvas (CT), Painel (PL), Três Barras (TB) e Urupema (UR), utilizando dez genótipos escolhidos aleatoriamente de cada, e; II) a brotação epicórmica de galhos destacados destas mesmas populações. Ambos os experimentos foram conduzidos em Lages, Santa Catarina. Em fevereiro de 2020, a estaquia foi avaliada de acordo com as porcentagens de: sobrevivência, calos, enraizamento, novas brotações e permanência das folhas originais. Os galhos foram avaliados a cada 30 dias após seu acondicionamento observando as porcentagens de galhos com brotações, número de brotações e comprimento em centímetros. Para a estaquia, houve baixa sobrevivência em todas as populações (<15%), mas com maior vigor em alguns genótipos, tais como TB1 (46%), TB7 e TB3 (ambos 28%). A maior parte das estacas vivas apresentou calo, característico de material de elevada maturidade. O enraizamento foi baixo nos níveis de população (<1,5%) e genótipo (<10%). Os galhos apresentaram brotações até 60 dias, com TB apresentando o maior número total de brotações (aproximadamente 300) e de maior comprimento médio (2,8 cm). Em termos gerais, a sobrevivência e o enraizamento de estacas foram afetados por ambos população e genótipo, destacando-se TB. Uma resposta similar foi observada para a brotação de galhos. Novos estudos contendo mais populações, análises mais aprofundadas das características dos galhos e melhores condições de acondicionamento são recomendadas..

ABSTRACT Drimys brasiliensis Miers, popularly known as cataia, is a tree species native to the Atlantic Forest that has phytochemical, phytotherapeutic, aromatic and economic importance, with wide use in folk medicine. It is considered a species of difficult multiplication via seeds, presenting dormancy due to embryonic immaturity. Thus, the objective of this study was to analyze the vegetative rescue, in vitro establishment and propagation by way of cuttings of Drimys brasiliensis. For the rescue, the girdling techniques were applied at 30 and 90 cm from the ground, semi-girdling at 30 cm from the ground and pruned branches conditioned vertically and horizontally, being evaluated the shoot emission capacity. With the shoots obtained by vegetative rescue, the explants used for in vitro establishment were made, evaluating different immersion times in sodium hypochlorite 1.0 % (v/v) (0, 10, 15 and 20 minutes). The percentages of total, bacterial, fungal contamination and phenolic oxidation were evaluated. On the cuttings, shoots from vegetative rescue, from the aerial part of an adult individual and from detached branches were tested and placed in a mini-tunnel. The percentage of cuttings survival, percentage of cuttings with callus and percentage of rooting were evaluated. Regarding the vegetative rescue, the technique of pruned branches resulted in the induction of shoots, highlighting the branches conditioned vertically (100%). In the in vitro establishment, the immersion in sodium hypochlorite (1%) for 20 minutes proved to be efficient in the control of fungal contamination, however, no significant differences were observed in relation to the control of bacterial contamination. In cuttings, the use of cuttings from pruned branches or girdling/semi-girdling showed potential for these techniques in the cloning of the species, obtaining results close to 10% rooting. In general, the species has the potential for vegetative propagation, however, adjustments are necessary in the in vitro establishment and cutting protocols.

RESUMO Drimys brasiliensis Miers, conhecida popularmente por cataia, é uma espécie arbórea nativa da Mata Atlântica que apresenta importância fitoquímica, fitoterapêutica, aromática e econômica, com amplo uso na medicina popular. É considerada uma espécie de difícil multiplicação via sementes, apresentando dormência por imaturidade embrionária. Assim, objetivou-se com este estudo analisar o resgate vegetativo, estabelecimento in vitro e a propagação via estaquia de Drimys brasiliensis. Para o resgate, realizou-se a aplicação das técnicas de anelamento a 30 e 90 cm do solo, semianelamento a 30 cm do solo e galhos podados acondicionados vertical e horizontalmente, sendo avaliada a capacidade de emissão de brotações. Com as brotações obtidas pelo resgate vegetativo, foram confeccionados os explantes utilizados para o estabelecimento in vitro, avaliando diferentes tempos de imersão em hipoclorito de sódio 1,0 % (v/v) (0, 10, 15 e 20 minutos). Foram avaliadas as percentagens de contaminação total, bacteriana, fúngica e oxidação fenólica. Na estaquia foram testadas brotações oriundas do resgate vegetativo, da parte aérea de indivíduo adulto e de galhos destacados e acondicionados em mini-túnel. Avaliaram-se a porcentagem de sobrevivência das estacas, porcentagem de estacas com calos e porcentagem de enraizamento. Em relação ao resgate vegetativo, a técnica de galhos podados resultou na indução de brotações, destacando os galhos acondicionados verticalmente (100%). No estabelecimento in vitro, a imersão em hipoclorito de sódio (1%) por 20 minutos se mostrou eficiente no controle da contaminação por fungos, entretanto, não foram observadas diferenças significativas em relação ao controle de contaminação bacteriana. Na estaquia, o uso de estacas provenientes de galhos podados ou anelamento/semianelamento mostrou potencial para estas técnicas na clonagem da espécie, obtendo resultados próximos a 10% de enraizamento. No geral, a espécie apresenta potencial de propagação vegetativa, contudo, são necessários ajustes nos protocolos de estabelecimento in vitro e estaquia.

ABSTRACT The aim of the work was to analyze the influence of variables such as shading, temperature and humidity in the production and rooting of mini-cuttings of Sequoia sempervirens (D. Dom) Endl. in a clonal mini-garden. The experiment was conducted at the Forest Nursery at the University of Santa Catarina State - CAV/UDESC, Lages - SC. The minicuttings were obtained by vegetative rescue of a single clone (A228). The original S. sempervirens individuals studied are located in the National Forest of São Francisco de Paula -RS (FLONA). Sprouts were collected 90 days after the application of girdling rescue techniques. Subsequently, mini-stumps were obtained, which were submitted to three different treatments: T1 - Mini-stumps without shading protection, T2 - Mini-stumps with single layer of shading and T3 - Mini-stumps with double layer of shading. There was no significant difference for humidity and temperature in relation to the production of mini-cuttings by the mini-stumps, while for shading the treatments T2 and T3 showed greater efficiency. It is possible that the shading treatments on S. sempervirens mini-stumps allows the vegetative tissue to be more juvenile, obtaining excellent results in cutting.

Resumo O objetivo do trabalho foi avaliar o efeito do hidrogel no plantio de mudas clonais de Eucalyptus urograndis em vasos, relacionados com diferentes manejos hídricos, buscando fornecer informações sobre a eficiência do uso do hidrogel. O experimento foi conduzido em viveiro florestal, esquema fatorial, em que o fator “A” se referiu à ausência e à presença de hidrogel e o fator “B” ao manejo hídrico (irrigação somente no plantio, 8 dias, 4 dias e diariamente). Foram realizadas avaliações da sintomatologia do estresse hídrico, características morfológicas, teores de clorofila, teor de água no solo, trocas gasosas, incremento em diâmetro e altura e biomassa seca. O hidrogel proporcionou um aumento no teor de água no solo e um atraso nos sintomas de estresse hídrico, aumentando a taxa de sobrevivência. O estresse hídrico foi um fator limitante para a abertura estomática, contribuindo para a queda na assimilação de carbono pela fotossíntese.

Abstract The objective of this study was to evaluate the effect of the hydrogel on the planting of clonal Eucalyptus urograndis seedlings in pots, related to different water management, to provide information about the hydrogel use efficiency. The experiment was carried out in a forest nursery in a factorial scheme, as factor “A” referred to the absence and presence of hydrogel and factor “B” to water management (0 - irrigation only at planting, 1 - daily, 4 - every 4 days, and 8 - every 8 days). Evaluations of the water stress symptomatology, morphological characteristics, chlorophyll content, soil water content, gas exchange, increase in diameter and height, and dry biomass were performed. The hydrogel provided an increase in water content in the soil and a delay in the symptoms of water stress, increasing the survival rate. Water stress was a limiting factor for stomatal opening, contributing to the decrease in carbon assimilation by photosynthesis.

Resumo Sequoia sempervirens (sequoia) é uma espécie conhecida pela qualidade superior de sua madeira, sendo a produção de mudas por miniestaquia uma alternativa viável. O objetivo do trabalho foi avaliar a posição de coleta, presença ou ausência de folhas aciculares em miniestacas e a produção de mudas cultivadas em diferentes substratos e utilização de AIB. Foram utilizadas miniestacas de diferentes clones, oriundas de minijardim clonal. Para o padrão de miniestacas utilizou-se a porção lignificada, com média lignificação e pouca lignificação, na presença ou ausência de folhas aciculares, avaliando-se um clone. Em relação aos substratos, observou-se o comportamento de três clones e quatro substratos de marcas comerciais. Para o emprego de regulador de crescimento utilizou-se um clone e diferentes concentrações de AIB (0,0 a 5000 mg L-1). As miniestacas foram colocadas para enraizar em estufim e avaliadas aos 90 dias. Todos os experimentos foram instalados em delineamento inteiramente casualizado, com posterior avaliação da porcentagem de sobrevivência; porcentagem de miniestacas com calos; porcentagem de miniestacas enraizadas e número de raízes emitidas por miniestaca enraizada. Miniestacas pouco lignificadas (ápice) com folhas aciculares apresentaram os melhores resultados para sobrevivência (96%) e enraizamento (94%); miniestacas muito lignificadas sem folhas aciculares obtiveram baixo enraizamento (10%). Houve considerável variação de enraizamento entre os substratos (66 a 100%) e o número de raízes foi mais influenciado pelo clone utilizado. Os melhores resultados foram observados naqueles com componentes mais orgânicos. O emprego de AIB na miniestaquia não foi significativo para nenhuma das variáveis analisadas. Miniestacas coletadas em porções apicais e com presença de folhas aciculares mostraram-se mais indicadas para trabalhos com a espécie. Para a seleção do melhor substrato deve-se observar o efeito clonal, priorizando-se substratos com composição mais orgânica. A utilização de AIB não influenciou positivamente o enraizamento de miniestacas, não sendo recomendado o seu uso.

Abstract Sequoia sempervirens (sequoia) is a species known for the superior quality of its wood, making plants production by minicuttings a viable alternative. The objective of the work was to evaluate the position of collection, presence or absence of acicular leaves in minicuttings and production of plants grown on different substrates and use of IBA. Minicuttings from different clones, from a clonal minigarden, were used. For the minicuttings pattern, use a lignified portion, with medium lignification and little lignification, in the presence or absence of acicular leaves, available if a clone. Regarding substrates, the behavior of three clones and four substrates of commercial brands. For the growth regulator, was used a clone and different concentrations of IBA (0.0 to 5000 mg L-1). Minicuttings were placed to root in mini-tunnel and evaluated at 90 days. All experiments were installed in completely randomized design, with subsequent assessment of the percentage of survival; percentage of minicuttings with calluses; percentage of rooted minicuttings and number of roots emitted by rooted minicuttings. Little lignified minicuttings (apex) with acicular leaves, showed the best results for survival (96%) and rooting (94%); very lignified minicuttings without acicular leaves obtained low rooting (10%). There was considerable variation in rooting between substrates (66 to 100%) and the number of roots was more influenced by the clone used. The best results were observed in those with more organic components. The use of IBA in the minicutting was not significant for any of the variables analyzed. Minicuttings collected in apical portions and with the presence of acicular leaves are more suitable for work with a species. To select the best substrate, must be observe the clonal effect, prioritizing substrates with a more organic composition. The use of IBA did not positively influence or reduce minicuttings, it was not recommended or its use.

Resumo Objetivou-se avaliar o efeito do hidrogel no plantio de mudas de Eucalyptus dunnii em vasos, relacionados com diferentes manejos hídricos. Utilizou-se mudas de aproximadamente 25 cm de altura plantadas em vasos preenchidos com 4,5 L de solo. O experimento foi realizado em DIC, esquema fatorial 2x3, com ausência e presença de hidrogel relacionados aos manejos hídricos (irrigação somente no plantio, a cada três e seis dias). Do plantio até o 47° dia foram realizadas avaliações da sintomatologia do estresse hídrico, teores de clorofila e trocas gasosas. Avaliou-se o desenvolvimento das mudas através da biomassa seca radicular e da parte aérea, além da determinação da curva de retenção de água. Como resultado, o uso do polímero proporcionou um aumento na retenção de água, e um atraso nos sintomas de estresse hídrico, aumentando assim os níveis de clorofila. Houve efeito direto nas trocas gasosas, sendo visível a recuperação das variáveis analisadas, 24 h após a irrigação. Avaliações da biomassa demonstraram que os tratamentos com o uso do hidrogel, apresentaram melhor desenvolvimento. O uso do polímero aumentou a qualidade das mudas, sendo uma alternativa de plantio em épocas secas do ano.

Abstract This study evaluated the effect of using hydrogel in the planting of Eucalyptus dunnii seedlings in pots, under different water-management regimens. Seedlings of approximately 25 cm height were planted in pots filled with 4.5 L of soil. The experiment was of Completely Randomized Design, in a 2x3 factorial, with absence and presence of hydrogel related to different water-management regimens (irrigation only in planting, every 3 to 6 days). From planting until the 47th day the seedlings were evaluated for the symptoms of water stress, chlorophyll content and gas exchange. Finally, the development of the plants was evaluated using the root dry weights and shoots, as well as by determining the water retention curve. As a result, the use of the polymer yielded an increase in water retention and a delay in the symptoms of drought stress, consequently increasing chlorophyll levels. One can observe the direct effect gas exchange of this kind, where recovery of the variables analyzed 24 h after irrigation was visible. Reviews of dry biomass demonstrated that treatment with the use of hydrogel showed the best development. However, the use of hydro retainer polymer increased the quality of Eucalyptus dunnii seedlings, besides being an alternative planting method in dry periods of the year.

RESUMO: A supressão dos macronutrientes é uma das maneiras de identificar qual ou quais dos elementos químicos é o mais importante no desenvolvimento inicial das mudas de espécies florestais. O estudo objetivou avaliar o crescimento inicial de mudas de Eucalyptus benthamii por meio de variáveis morfológicas e fisiológicas, submetidas a doses de N, P e K, e calagem. O delineamento experimental para instalação do experimento foi em delineamento inteiramente casualizado, com esquema fatorial 2x9, em que os níveis do fator “A” se referiram a ausência e a presença de calagem e os níveis do fator “B” aos diferentes tratamentos de NPK. Variáveis morfológicas de DAC (diâmetro a altura do colo) e H (altura) e as variáveis fisiológicas de A (fotossíntese), E (transpiração), gs (condutância estomática), Ci/Ca (relação entre a concentração intercelular e atmosférica de CO2) e WUE (eficiência no uso da água) foram determinadas. Para as variáveis morfológicas, a ausência do N afetou diretamente as médias, havendo uma relação direta entre o aumento da dose com o aumento das variáveis. Há uma relação positiva do P principalmente em relação a MSPA e MSPR. Para as variáveis fisiológicas, não houve resposta direta com as doses de N ou P, sendo o K o elemento que mais influenciou as variáveis, principalmente quando o calcário foi aplicado, resultando em maiores médias para fotossíntese, transpiração e condutância estomática. Com o objetivo de atender às demandas morfológicas e fisiológicas, a recomendação para o cultivo de Eucalyptus benthamii nas condições deste estudo é a dose 150-200-150, sem aplicação de calagem.

ABSTRACT: Macronutrient suppression is one way to identify which chemical elements is the most important in the early development of seedlings of forest species. This study evaluated the initial growth of Eucalyptus benthamii seedlings through morphological and physiological variables, submitted to doses of N, P and K, and liming. The experimental design to install the experiment was completely randomized, with a 2x9 factorial scheme, in which levels of factor “A” referred to absence and presence of liming and levels of factor “B”, to the different treatments of NPK. Morphological variables of SD (stem diameter) and H (height) and the physiological variables of A (photosynthesis), E (transpiration), gs (stomatal conductance), Ci/Ca (relationship between intercellular and atmospheric CO2 concentration) and WUE (water use efficiency) were measured. For morphological variables, the absence of N directly affected the means and there was a direct relationship between increase of the dose and increase of SD and H. There was a positive relationship of P mainly in relation to shoot dry matter content (SDMC) and root dry matter content (RDMC). For the physiological variables, there was no direct response with the doses of N or P, with K being the element that most influenced the variables, especially when limestone was applied, resulting in higher averages for photosynthesis, transpiration and stomatal conductance. With the purpose of meeting the morphological and physiological demands, the recommendation for cultivation of Eucalyptus benthamii under the conditions of this study is the doses 150-200-150, without liming application.

Resumo A adição de polímeros hidroretentores visa aumentar a capacidade de retenção de água no solo, propiciando maior taxa de sobrevivência das mudas e permitindo o plantio em épocas distintas do ano. O objetivo do presente estudo foi avaliar o efeito do uso do hidrogel no plantio de mudas de Eucalyptus dunnii em vasos, relacionado com diferentes manejos hídricos, simulando condições de campo em solo do tipo Cambissolo Húmico. O experimento foi conduzido em delineamento inteiramente casualizado, com arranjo fatorial (hidrogel e frequência de irrigação). O fator hidrogel foi composto por presença ou ausência do polímero, e a frequência de irrigação por irrigação somente no plantio, a cada 8 dias, 4 dias e diariamente. Foram realizadas avaliações da sintomatologia do estresse hídrico, aspectos morfométricos, teor de água no solo e trocas gasosas. O hidrogel proporcionou aumento no teor de água no solo e o adiamento nos sintomas de estresse hídrico, principalmente quando a irrigação foi efetuada com menor frequência. A adição do polímero também proporcionou melhoria na qualidade das mudas, com maior acúmulo de massa seca. O estresse hídrico foi um fator limitante para a abertura estomática. Quanto menor a disponibilidade de água, menores foram os valores de fotossíntese, condutância estomática e transpiração. Em geral, os resultados obtidos confirmam que a adição de hidrogel no solo otimiza a disponibilidade de água, com possibilidade de redução da mortalidade no plantio e maximização do crescimento das plantas na fase inicial de estabelecimento.

Abstract The addition of water-repelling polymers aims to increase water retention capacity in the soil, providing higher seedling survival rate and allowing planting at different times of the year. The objective of the present work was to evaluate the effect of hydrogel use on planting Eucalyptus dunnii seedlings in pots, related to different water management, simulating field conditions in a Humic Cambisol soil. The experiment was conducted in a completely randomized design with factorial arrangement (hydrogel and irrigation frequency). The hydrogel factor was composed by the presence or absence of the polymer, and the frequency of irrigation by irrigation only at planting, every 8 days, 4 days and daily. Water stress symptomatology, morphometric aspects, soil water content and gas exchange were evaluated. The hydrogel provided an increase in soil water content and delayed symptoms of water stress, especially when irrigation was less frequent. The addition of the polymer also provided improved seedling quality, more accumulated dry mass. Water stress was a limiting factor for stomatal opening. The lower the water availability, the lower the photosynthesis, stomatal conductance and transpiration values. In general, the results confirm that the addition of hydrogel in the soil optimizes water availability, with the possibility of reducing planting mortality and maximizing plant growth in the initial phase of establishment.

RESUMO: O trabalho teve como objetivo mensurar os efeitos de déficit hídrico, saturação e efeito da salinidade em mudas de Toona ciliata. Foram testados sete tratamentos: controle, suspensão completa de irrigação, saturação permanente do solo no vaso e quatro diferentes doses de NaCl (50, 100, 200 e 400 µmol). O delineamento experimental utilizado foi inteiramente casualizado, com oito repetições. Foram realizadas avaliações fisiológicas ao longo do experimento e ao final, avaliações morfológicas. As plantas foram responsivas aos estresses aplicados comparativamente ao controle. Havendo redução em variáveis morfológicas e fisiológicas em todos os tratamentos sobre estresse. Todos os indivíduos sob estresse tiveram uma pequena recuperação ao final do experimento, iniciando a rebrotar, representando uma possível adaptação ao estresse.

ABSTRACT: The objective of this paper was to test the effects of water deficit, saturation and salinity in individuals of Toona ciliata. Seven treatments were tested: the control group, the complete suspension of irrigation, the permanent saturation of the pot soil and four doses of NaCl (50, 100, 200 and 400 µmol). The experimental design was completely randomized, with 8 repetitions in each treatment. Physiologic evaluations were carried out during the experiment, and morphologic evaluations at the end. The plants were responsive to the applied stresses comparatively to the control group. Reductions were observed in morphological and physiological variables in all treatments under stress. All individuals under stress recovered slightly in the end of the experiment, and began to sprout again, representing a probable adaptation to the conditions.

ABSTRACT Sequoia sempervirens is different from other species not only for its excellent vigor and longevity, but also for quality wood productivity. The objective of this work was to evaluate the rooting of Sequoia sempervirens mini-cuttings in different cultivation environments. In both experiments, rooting was evaluated in time to determine the root development in each environment. Mini-cuttings from clone A228 from clonal mini-garden were used. In the first experiment the material was placed to take root in three different environments: greenhouse (GH), shadehouse (SH) and mini-tunnel, with evaluation performed every 30 days (from 30 to 150 days). In the second experiment, we compared the development and rooting in mini-tunnel, greenhouse with intermittent mist (GWIM), with weekly evaluations (from 30 to 93 days). Both experiments were installed in a completely randomized design, with subsequent evaluation of the survival percentage, percentage of rooted cuttings and number of roots emitted by rooted cuttings. Humidity and temperature data were also collected in all environments observed. The mini-tunnel was the most efficient place for sequoia mini-cutting, presenting higher survival, rooting and number of roots when compared to the shadehouse and the greenhouse. In addition, it provided rooting similar to the greenhouse with intermittent mist (close to 90%). It is recommended to keep mini-cuttings in a mini-tunnel or greenhouse with intermittent mist for a period of 90 days for proper rooting to occur. Good temperature control was also observed in this structure, as well as excellent humidity control. The mini-tunnel can be used for sequoia propagation by mini-cuttings as it has shown good rooting results (> 80%).

ABSTRACT The vegetative growth of plants depends on the nutritional conditions of the soil, mainly in relation to the N element. This element favours the formation of cytokines and auxins, essential hormones for sprouting and rooting, respectively. The objective of this study was to evaluate the influence of nitrogen fertilization of Ilex paraguariensis mother trees on epicormic sprouts emission and rooting of its cuttings. Five treatments of fertilization were applied on the mother trees: control; 250 g of urea (N); 250 g of NPK (5-20-10); 500 g of NPK, and; 250 g of NPK with 30 g of micronutrients. Two evaluations (at 240 and 480 days) were carried out for: trees with sprouts emission (%), average sprouts number and their average length (cm). Sprouts were collected at both vegetative evaluations after the application of the experiment (August 2016) and sectioned into cuttings. Cuttings variables were evaluated: survival (%); rooting (%), callus formation (%) and average root number. The best response to epicormic sprouts emission was obtained with 250 g of NPK at 480 days for trees with sprouts (>75%), sprouts number (4.4) and sprouts length (9.9), but considerable results were also obtained at 240 days with urea. For cuttings, the best results were also obtained from sprouts obtained at 480 days for most treatments (>80% survival and rooting). Nitrogen fertilization is essential for a successful vegetative rescue and propagation by cuttings of I. paraguariensis, and longer periods may be able to boost these results.

ABSTRACT We analyzed the rooting of sequoia mini-cuttings from different clones in the four seasons of the year and the use of the logistic model to estimate the time of maximization of rooting in each factor of analysis. Mini-cuttings of five clones grown in clonal mini-garden were placed to root in mini-tunnel in four seasons of the year. Weekly evaluations were performed (from 30 to 93 days) of these variables: survival (%), rooted mini-cuttings (%) and a number of emitted roots. These data were used to adjust the original logistic function. The experiment was set in completely randomized design, in a factorial scheme of 5 (clones) x 4 (seasons), using five replicates of 50 mini-cuttings per experimental unit. During the winter the lowest rooting of mini-cuttings was achieved (85%), with rates higher than 90% in other seasons. In winter, slower rooting also occurred, around 60-70 days, while in other seasons it was between 50-60 days after mini-cutting planting. The rooting process is dependent on the clones. Our data showed that four clones presented rooting greater than 90% and one less than 70%. In general, mini-cuttings can be performed at any time of the year, recommending the period of 90 days in mini-tunnel.

ABSTRACT The induction of epicormic shoots is very important for the success of vegetative propagation in forestry species, due to the high rooting capacity of the reinvigorated material. However, it is necessary to determine the most appropriate technique for this purpose, aiming for greater productivity and better reinvigoration, which may be different for each species. The objective of this search was to evaluate different induction techniques for the production of epicormic shoots in I. paraguariensis mother trees in the municipality of Urupema, Santa Catarina state, considering four rescue techniques: complete girdling (100%); semi-girdling (50%); detached live branches, and; shoots of the treetop (canopy). Three evaluations were made for: trees with epicormic shoots (%), average number of shoots and their average length (cm). Shoots were collected at 180 days after (February 2017) the application of the experiment (August 2016), separating in: rejuvenated shoots and of the treetop. At 90 days, cuttings variables were evaluated: rooting (%), calogenesis (%), average root number and their average length (cm). The semi-girdling was superior to shoot length (5.3 cm). The detached live branches obtained the highest average number of shoots (4.7), however, they were not able for cutting, due to their short length (0,6 cm). For cutting, there was only difference for the number of roots formed, and the rejuvenated material was superior (2,3) than treetop (0.8). It is recommended the use of semi-girdling technique for greater production of juvenile shoots and use reinvigorated cuttings for vegetative propagation, considering the greater number of roots formed.

RESUMO Mimosa scabrella é uma espécie pioneira que ocorre principalmente na floresta ombrófila mista do Sul do Brasil, apresentando considerável importância econômica. Considerando as limitadas informações acerca dos substratos mais adequados para a produção de mudas da espécie, neste trabalho avaliou-se o efeito combinado do uso de hidrogel com três tipos de substratos e quatro fertilizantes no crescimento inicial e qualidade de mudas de M. scabrella. Os substratos foram preparados com proporções distintas de um substrato orgânico comercial, vermiculita (VM) e casca de pinus (PB): 1 (70% de TF, 10% de VM e 20% de PB), 2 (40% de TF e VM e 20% of PB), e 3 (70% de TF, 10% de VM e 20% de PB). Os fertilizantes consistiram de uma fórmula de liberação lenta (A), o tradicional NPK (B), um composto de superfosfato simples e de cloreto de potássio (C) e com fertilizante ausente (D). Os três compostos de substratos foram combinados com cada fertilizante na presença ou ausência de hidrogel (arranjo fatorial). O uso de hidrogel promoveu um efeito positivo no crescimento das mudas de M. scabrella, provavelmente retendo mais água e permitindo maior absorção de nutrientes. No geral, o polímero implicou em aumento no índice de qualidade de Dickson (DQI). Adicionalmente, a combinação do composto orgânico e vermiculita em proporções equilibradas adicionado de casca de pinus (substrato 2) constituíram o melhor substrato. A adição dos fertilizantes A e B resultaram na melhor performance de crescimento. Concluiu-se que a combinação de hidrogel com substrato composto e fertilizantes melhoraram os índices de qualidade de mudas de M. scabrella.

ABSTRACT Mimosa scabrella is a pioneer species that occurs mainly in the ombrophilous mixed forests of southern Brazil, assuming considerable economic relevance. As limited information is available concerning the most adequate substrates for producing seedlings of this species, we evaluated the combined effect of hydrogel with three types of substrates and four fertilizers in the initial growth and quality of seedlings of M. scabrella. The substrates were prepared with distinct proportions of a commercial organic substrate, vermiculite (VM) and pine bark (PB): 1 (70% of TF, 10% of VM and 20% of PB), 2 (40% of each TF and VM and 20% of PB), and 3 (70% of TF, 10% of VM and 20% of PB). The fertilizers consisted of a slow release formula (A), a traditional NPK (B), a compost of superphosphate and potassium chloride (C) and no fertilizer (D). The three soil mixtures were combined with each fertilizer in the presence or absence of hydrogel (factorial arrangement). The use of hydrogel promoted a positive effect on the growth of M. scabrella seedlings, probably by retaining more water and enabling increased nutrient absorption. In general, the polymer implicated in increased Dickson quality index (DQI). Additionally, the combination of organic compound and vermiculite in equilibrated proportions aid by pinus bark (substrate 2) were the best substrate. Finally, adding the fertilizers A or B resulted in the best growth performance. In conclusion, the combined effect of hydrogel, substrate mixture and fertilizers improved the quality indexes of M. scabrella seedlings.