ABSTRACT Light is a determining factor in plant morphophysiology, as it influences the growth and development of agricultural crops. Thus, the objective was to investigate the effects of light sources on the growth and development of “biquinho” pepper cultivars. The experiment was performed in two stages (Exp1 and Exp2), evaluating two cultivars (BRS Moema; Airetama biquinho) in five light sources (white LEDs, red LEDs, blue LEDs, red/blue LEDs, and fluorescent lamps). In Exp1 the plants were kept in a controlled condition, with a completely randomized design, in a 2x5 factorial scheme (cultivars x light sources) until 76 days after emergence (DAE), in which growth variables and photosynthetic pigments were evaluated. In Exp2, the plants were removed from the above conditions and transplanted in pots, being kept in greenhouse for more 76 DAE. At 152 DAE, the same variables as Exp1 were evaluated, as well as gain of shoot fresh and dry mass, and gain of root fresh and dry mass. In both experiments, growth variables were affected by cultivar and the light sources, however, the behavior did not follow the same trend for all variables, indicating that the light quality influences the growth of the crops, and impacting during greenhouse conditions.

ABSTRACT. Strawberry is an economically and socially important crop in several regions worldwide. Thus, studies that provide information on topics in strawberry growth are important and must be constantly updated. The aims of this study were to fit a logistic growth model to describe strawberry fruit production and to estimate the partial derivatives of the fitted model in order to estimate and interpret the critical points, in addition to using multivariate analyses. To do this, data on 16 treatments [combinations of two cultivars (Albion and Camarosa), two origins (national and imported), and four mixed organic substrates (70% crushed sugar cane residue + 30% organic compost, 70% crushed sugar cane residue + 30% commercial substrate, 70% burnt rice husk + 30% organic compost, and 70% burnt rice husk + 30% commercial substrate)] conducted in a randomized complete block design (RCBD) with four replicates were used. A logistic model was fitted to the accumulated fruit production stratified by treatment and replication. Partial derivatives related to the accumulated thermal sum were estimated in order to quantify the critical points of the model. Subsequently, a principal component analysis was performed. The results show that the use of growth models substantially increases the inferences that can be made about crop growth, and the multivariate analysis summarizes this information, simplifying its interpretation. Approaches such as those carried out in this study are still rarely used, but, compared to simpler models, they increase the amount of inferences that can be made and provide greater elucidation of the results.

ABSTRACT Eugenia uniflora is an American tree species with ecological, agronomical and medicinal importance. However, just few studies have focused on the in vitro propagation and production of secondary metabolites. This study investigated the explant sources and culture conditions for the in vitro callogenesis in E. uniflora towards induction of somatic embryogenesis and production of antioxidant compounds. Nodal segments, leaf sections and root segments from in vitro germinated seeds were used as explants and eight different combinations of auxins (2,4-D or NAA) and cytokinins (BAP or TDZ) were tested for the callus induction. The best callogenic response was observed in nodal segments, followed by leaf sections. Root segments presented comparatively poorer callogenic performance. Calli from nodal segments cultivated in MS medium with NAA (10 µM) + TDZ (5 µM) originated putative pro-embryogenic structures, while the culture in liquid medium using MS supplemented with NAA (10 µM) + TDZ (5 µM) revealed significantly higher content of phenols and flavonoids, as well as higher reducing capacity than the tested treatments and the control (fresh leaves). In summary, the calli obtained from nodal segments revealed competence for somatic embryogenesis induction and development as well as the production of secondary metabolites with pharmaceutical potential.

RESUMEN Eugenia uniflora es una especie arbórea americana de importancia ecológica, agronómica y medicinal. Sin embargo, pocos estudios se han centrado en la propagación y producción in vitro de metabolitos secundarios. Este estudio investigó las fuentes de explantes y las condiciones de cultivo para la callogénesis in vitro en E. uniflora para la inducción de embriogénesis somática y la producción de compuestos antioxidantes. Se utilizaron segmentos nodales, secciones de hojas y segmentos de raíz de semillas germinadas in vitro como explantes y se probaron ocho combinaciones diferentes de auxinas (2,4-D o ANA) y citoquininas (BAP o TDZ) para la formación de callos. La mejor respuesta callogénica se observó en segmentos nodales, seguidos de secciones foliares. Los segmentos de raíz presentaron un rendimiento callogénico comparativamente menor. Los callos de segmentos nodales cultivados en medio de cultivo MS con NAA (10 µM) + TDZ (5 µM) originaron estructuras proembriogénicas putativas, mientras que el cultivo en MS medio líquido con ANA (10 µM) + TDZ (5 µM) reveló un contenido significativamente mayor de fenoles y flavonoides, así como una mayor capacidad reductora que los tratamientos probados y el control (hojas frescas). En resumen, los callos obtenidos de segmentos nodales revelaron competencia para la inducción y el desarrollo de embriogénesis somática, así como para la producción de metabolitos secundarios con potencial farmacéutico.

RESUMO O nitrogênio (N) é um elemento dinâmico no solo. Dessa forma, novas alternativas de fertilização nitrogenada são demandadas, como forma de maximizar a sua eficiência. Aliado a isso, os sensores de vegetação surgem como forma de avaliar e manejar as demandas nutricionais das plantas. Objetivou-se avaliar o efeito de fontes de nitrogênio nos pigmentos fotossintéticos e sua correlação com o rendimento de grãos e biomassa seca em milho. O experimento foi conduzido em blocos casualizados com fontes de nitrogênio (mineral, orgânica e biológica). Avaliaram-se os teores de clorofila a, b e total, bem como de carotenoides. Os índices de clorofila avaliados por ambos os métodos se correlacionaram positivamente entre si e com o rendimento de grãos por planta. A adubação nitrogenada 100 % mineral foi superior, quando comparada com os demais tratamentos, com incrementos de até 44 %. Verificou-se relação positiva entre os métodos de determinação e a estimativa dos teores de clorofila. O rendimento de grãos por planta apresentou os maiores valores quando se utilizou a fonte de adubação 100 % mineral, apresentando incrementos acima de 10 %, em relação às demais fontes, com gasto de US$ 89.77 com o fertilizante e ganho acima de US$ 538.60 para o rendimento de grãos. Verificou-se correlação positiva entre os pigmentos fotossintetizantes avaliados por ambos os métodos e o rendimento de grãos por planta. Recomendam-se ambos os métodos para a avaliação das concentrações de clorofila.

ABSTRACT Nitrogen (N) is a dynamic element in the soil, so new nitrogen fertilization alternatives are required as a way of maximizing its efficiency. Besides, vegetation sensors are a way to assess and manage the nutritional demands of plants. This study aimed to evaluate the effect of nitrogen sources on photosynthetic pigments and their correlation with corn grain yield and dry biomass. The experiment was carried out in a randomized block design with nitrogen sources (mineral, organic and biological). Contents of chlorophyll a, b and total, as well as carotenoids, were evaluated. The chlorophyll indices evaluated by both methods were positively correlated with each other and with the grain yield per plant. Nitrogen fertilization 100 % mineral was superior, when compared to the other treatments, with increments of up to 44 %. There was a positive relationship between the methods of determining and estimating the chlorophyll contents. The grain yield per plant showed the highest values when using the 100 % mineral fertilizer source, with increments above 10 %, in relation to the other sources, spending US$ 89.77 on fertilizer and earning over US$ 538.60 on grain yield. There was a positive correlation between the photosynthetic pigments obtained by both methods and grain yield per plant. Both methods are recommended for the evaluation of chlorophyll concentrations.

RESUMO: O objetivo deste estudo foi caracterizar a produção de pimenta biquinho através da interpretação dos parâmetros do modelo Logístico e seus pontos críticos obtidos pelas derivadas parciais da função, bem como indicar qual a melhor cultivar e a melhor época de cultivo para locais de clima subtropical. Conduziu-se um experimento em esquema fatorial 2x3 sendo duas cultivares de pimenta biquinho (BRS Moema e Airetama biquinho), em três épocas de cultivo (E1: outubro de 2015, E2: 01 de novembro 2015 e E3: janeiro de 2016). Ajustou-se o modelo logístico para massa de frutos em função da soma térmica acumulada, e calculou-se os pontos críticos através das derivadas parciais do modelo com a finalidade de caracterizar o desempenho produtivo da cultura através da interpretação biológica destes parâmetros. Temperaturas próximas a 0 ºC durante o experimento foram letais às plantas, e por isso, para a época 3, ajustou-se um modelo de regressão linear. A interpretação dos parâmetros do modelo Logístico e seus pontos críticos permitiram que a produção das cultivares nas épocas 1 e 2 fossem caracterizadas, sendo que a cultivar mais produtiva é Airetama biquinho em todas as épocas de transplante. Essa cultivar também apresenta maior concentração de produção no período. Quanto a precocidade produtiva as duas cultivares não diferiram significativamente. Sobre a época 3, não foi possível interpretar da mesma forma, pois o ajuste do modelo linear não permite as mesmas interpretações realizadas para o modelo não linear, reafirmando a sua aplicabilidade em cultura olerícolas de múltiplas colheitas.

ABSTRACT: The objective of this study was to characterize the production of biquinho pepper through the interpretation of parameter estimates from the logistic model and its critical points obtained by the partial derivatives of the function, and to indicate the best cultivar and growing season for subtropical climate sites. For this, a 2x3 factorial experiment was conducted with two cultivars of biquinho pepper (BRS Moema and Airetama biquinho) in three growing seasons (E1: October 2015, E2: November 2015, E3: January 2016). The logistic non-linear model for fruit mass was specified as a function of the accumulated thermal sum, and the critical points were calculated through the partial derivatives of the model, in order to characterize the productive performance of the crop by the biological interpretation of the estimates of the three set parameters. In E3, temperatures close to 0 ºC during the experiment were lethal to the plants, and a linear regression model was used in this case. The production of the cultivars in E1 and E2 were well characterized by the estimated logistic models, and the most productive cultivar was Airetama biquinho in all evaluated seasons. This cultivar also presented higher concentration of production. The two cultivars did not differ significantly with regards to productive precocity. For E3, it was not possible to interpret the parameters in the same way as for E1 and E2, since the use of the linear model did not allow the same interpretations performed for the nonlinear model, reaffirming its applicability horticultural crops of multiple harvests.

ABSTRACT. The objective of this study was to estimate the coefficient of repeatability and the number of measurements required for production and quality variables in a strawberry crop. An experiment was conducted with two strawberry cultivars from two origins grown in four substrate mixtures, totaling 16 treatments, evaluated in a randomized block design with four replications. Mass (MF) and number (NF) of fruits per plant were evaluated as measures of production, and total soluble solids (SST), titratable acidity (AT) and firmness (FIR) of fruits during the crop cycle were evaluated as measures of quality. Subsequently, the repeatability coefficient was estimated by the following methods: analysis of variance (ANOVA), principal component analysis using a correlation matrix (PCcor), principal component analysis using a variance-covariance matrix (PCcov) and structural analysis (SA). The number of measurements was adjusted for each studied variable based on determination coefficients of 0.80, 0.85, 0.90, and 0.95. The repeatability coefficients ranged from low to medium. The ANOVA method gave the lowest r values, while the PCcov method presented the highest values of r. When using the PCcov method, 3.6, 2.9, 6.2, 3.2, and 3.8 measurements were needed to reach 80% confidence for the variables MF, NF, SST, AT, and FIR, respectively, and this increased to 7.3, 14.0, 29.6, 15.4, and 18.1 for 95% confidence in the results for MF, NF, SST, AT, and FIR, respectively.

RESUMEN Los metabolitos secundarios son producidos por ciertas especies de plantas, y pueden influir en el desarrollo de algunas especies, debido a la acción de los efectos alelopáticos. Por lo tanto, el objetivo del trabajo fue evaluar el efecto alelopático del aceite esencial de Lippia alba en la germinación, emergencia y vigor de las plántulas de diferentes lotes de semillas de lechuga. El experimento se realizó en un diseño completamente al azar, en un esquema factorial 3x5, que consta de tres lotes de semillas del cultivar Grand Rapids® y cinco dosis de aceite esencial de L. alba (0; 0,25; 0,50; 0,75 y 1,00%) diluido en agua destilada y homogeneizado en Tween® 80. Se evaluó la germinación y el vigor de la semilla en el laboratorio (experimento I) y la emergencia en un ambiente protegido (experimento II). Los resultados obtenidos mostraron que hubo un efecto inhibitorio con una reducción significativa de la germinación, el vigor y la emergencia de la semilla cuando se añadió aceite esencial de L. alba a partir de concentraciones de 0.25%. El aceite esencial mostró potencial alelopático sobre diferentes lotes de semillas de lechuga, afectando la germinación, el vigor y la emergencia de las semillas.

ABSTRACT Secondary metabolites are produced by certain plant species and may influence the development of some species through the action of allelopathic effects. Thus, the objective of this study was to evaluate the allelopathic effect of Lippia alba essential oil on the germination, emergence and vigor of seedlings of different batches of lettuce seeds. This experiment was conducted in a completely randomized design with a 3x5 factorial scheme consisting of three batches of seeds of the cultivar Grand Rapids® and five doses of L. alba essential oil (0, 0.25, 0.50, 0.75 and 1.00%) diluted in distilled water and homogenized in Tween® 80. Seed germination and vigor, in the laboratory (experiment I), and emergence, in a protected environment (experiment II), were evaluated. The results demonstrated that there was an inhibitory effect with a significant reduction of germination, vigor and seed emergence when L. alba essential oil was added starting at concentrations of 0.25%. The essential oil showed allelopathic potential over different lettuce seed lots, affecting germination, vigor and seed emergence.

Resumo Devido a sua relevante importância econômica, tanto para o setor alimentício quanto farmacêutico, a oliveira vem sendo cada vez mais cultivada em todo o mundo. Para isso, a obtenção de mudas de qualidade com uniformidade e idoneidade varietal surge como fator altamente relevante na implantação dos pomares de oliveiras. Dessa forma, o objetivo deste trabalho foi desenvolver protocolo de estabelecimento in vitro a partir de segmentos nodais de duas cultivares de oliveira sob diferentes concentrações de hipoclorito de sódio e concentrações de BAP. O experimento foi conduzido no delineamento inteiramente casualizado, em esquema fatorial triplo (2x3x3), sendo duas cultivares de oliveira (Arbequina e Koroneiki), três concentrações de BAP (0,00; 2,22 e 4,44 µM) e três concentrações de hipoclorito de sódio (0,6; 0,8 e 1,0% de cloro ativo) para a descontaminação dos explantes. Cada tratamento contou com três repetições e a unidade experimental constituída por cinco tubos de ensaio com um explante cada. Após 28 dias, foi possível observar que os tratamentos testados não promoveram o estabelecimento in vitro de Olea europaea cv. Arbequina. A concentração de 2,22 µM de BAP adicionada ao meio WPM e a concentração de 1,0% de hipoclorito de sódio, utilizada na desinfestação dos explantes, apresentaram resultados promissores no estabelecimento in vitro de Olea europaea cv. Koroneiki.

Abstract Due to its relevant economic importance, both for the food and pharmaceutical sectors, the olive tree is being increasingly cultivated around the world. For this, obtaining quality seedlings with uniformity and varietal suitability emerges as a highly relevant factor at the implantation of olive orchards. Thus, the objective of this work was to develop in vitro establishment protocol from nodal segments of two olive cultivars under different concentrations of sodium hypochlorite and different concentrations of BAP. The experiment was conducted on completely randomized design, in a triple factorial scheme (2x3x3), two olive cultivars (Arbequina and Koroneiki), three BAP concentrations (0,00; 2,22 e 4,44 µM) and three concentrations of sodium hypochlorite (0,6; 0,8 and 1,0% active chlorine) for the decontamination of the explants. Each treatment had three replicates and the experimental unit consisted of five test tubes with one explant each. After 28 days, it was possible to observe that the treatments tested did not promote in vitro establishment of Olea europaea cv. Arbequina. The concentration of 2,22 µM of BAP added to the WPM and the 1,0% concentration of sodium hypochlorite used in disinfestation of the explants, presented promising results in the in vitro establishment of Olea europaea cv. Koroneiki.

RESUMEN El objetivo de este trabajo fue identificar y estimar las relaciones entre variables componentes de producción y rendi miento de frutos en tomate. El experimento se realizó con diseño de bloques al azar con un arreglo factorial 2x3x3, correspondiendo a dos híbridos de tomate (Netuno y San Vito), tres dosis de boro (H3BO3 - 0, 2, 4 g/sitio) y calcio (si aplicación, aplicación cada 7 días y aplicación cada 14 días), para un total de 18 tratamientos, cuatro repeticiones y 20 plantas por parcela. Se estimaron los coeficientes de correlación de Pearson entre las variables medidas, poste riormente, se seleccionaron aquellos con mayor significancia para la productividad mediante el método Stepwise y la verificación de la multicolinealidad por el número de condiciones y el factor de inflación de la varianza. Las correla ciones de las variables seleccionadas fueron descompuestas en efectos directos e indirectos sobre la productividad de los frutos mediante el análisis de coeficientes de trayectoria. Se encontró una fuerte correlación entre las variables, excluyendo las variables altura, diámetro y masa promedio de los frutos. Por lo tanto, existen relaciones de causa y efecto entre la variable independiente la masa total de frutos y la variable principal de productividad total de frutos, y las variables diámetro y número total de frutos no contribuyeron a aumentar la productividad de tomate.

ABSTRACT The objective of this study was to identify and estimate the relationships between production component variables and fruit yields in tomatoes. This experiment was conducted in a randomized block design with a 2x3x3 factorial arrangement, with two tomato hybrids (Netuno and San Vito), three doses of boron (H3BO3 - 0, 2, 4 g/pit) and three calcium floral applications (no application; application every 7 days; and application every 14 days), totaling 18 treatments with four replications and 20 plants per plot. Pearson correlation coef ficients were estimated between the measured variables and, after that, those with greater significance were selected for productivity with the Stepwise method and verification of multicollinearity using the number of condition and inflation factor of the variance. The correlations of the selected variables were decomposed into direct and indirect effects on fruit productivity with path analysis. There was a strong correlation be tween the variables, excluding the variables height, diameter and average mass of the fruits. Thus, there were cause and effect relationships between the independent variable total mass of the fruits and the principal variable total fruit yield. The variables diameter and total number of fruits did not contribute to an increased tomato production.

Resumo A fonte de luz na cultura de tecidos muitas vezes é um dos fatores pontuais para a adequação da produção de plantas, para isso, vêm se utilizando os diodos emissores de luz (LEDs) no intuito de aumentar o crescimento e desenvolvimento das plantas propagadas in vitro. O objetivo do trabalho foi avaliar a propagação in vitro de cultivares de Alpinia purpurata ‘Red Ginger’ e ‘Pink Ginger’ em duas diferentes fontes de luz (lâmpadas tubulares fluorescentes ou LED Branco). O experimento foi conduzido em delineamento inteiramente casualizado, esquema fatorial (2x2), totalizando quatro tratamentos com dez repetições, e a unidade experimental composta por um frasco contendo cinco explantes. Após 55 dias, foi possível observar que lâmpadas LED branco e a cultivar Red Ginger proporcionaram o maior número de brotos. Já para o número de folhas, a cultivar Red Ginger e lâmpadas LED branco proporcionaram resultados superiores. Para comprimento da parte aérea, a cultivar Red Ginger mantida sob lâmpadas fluorescentes foi superior, e a Pink Ginger apresentou superioridade quando cultivada sob luzes LED. Assim, mesmo com respostas diferenciadas entre genótipos, sugere-se o uso de lâmpadas LED branco na propagação in vitro das cultivares de Alpinia purpurata ‘Red Ginger’ e ‘Pink Ginger’.

Abstract The light source in tissue culture is often one of the punctual factors for the adequacy of plant production. For this, light emitting diodes (LEDs) have been used in order to increase the growth and development of the plants propagated in vitro. The objective was to evaluate the in vitro propagation of cultivars of Alpinia purpurata ‘Red Ginger’ and ‘Pink Ginger’ in two different light sources (fluorescent or LEDs tubes). The experiment was conducted in a completely randomized design, factorial scheme (2x2), totaling four treatments with ten replicates, and the experimental unit composed of one flask containing five explants. After 55 days, white LED and the ‘Red Ginger’ provided the highest number of shoots. For the number of leaves, the cultivar ‘Red Ginger’ and white LED lamps provided superior results. For shoot length (cm), the cultivar ‘Red Ginger’ kept under fluorescent lamps was superior, and ‘Pink Ginger’ presented superiority when cultivated under LED lights. Thus, even with differentiated responses among genotypes, the use of white LED lamps in the in vitro propagation of Alpinia purpurata ‘Red Ginger’ and ‘Pink Ginger’ cultivars is suggested.

RESUMO A produção e a qualidade dos morangos podem variar de acordo com a cultivar, a origem das mudas e o sistema de cultivo das plantas. O objetivo deste trabalho foi avaliar o efeito de diferentes substratos orgânicos e diferentes origens de mudas na produção de morangos e na qualidade dos frutos. O experimento foi conduzido em blocos ao acaso, em esquema fatorial 2x2x4, com duas cultivares (Albion e Camarosa, de dias neutros e dias curtos, respectivamente), duas origens de mudas (nacional-Brasileira e importada-Argentina) e quatro combinações de substratos: (Bagaço de cana-de-açúcar triturada [70%] + Composto orgânico [30%], Bagaço de cana-de-açúcar triturada [70%] + substrato comercial Carolina® [30%], casca de arroz queimada [70%] + composto orgânico [30% ] e cascas de arroz queimadas [70%] + substrato comercial Carolina® [30%]). A unidade experimental foi composta por oito plantas, com repetição em quatro blocos. Foram avaliados parâmetros de qualidade: acidez total titulável, sólidos solúveis totais, proporção de açúcar/acidez, firmeza, coloração da polpa (chroma, ângulo de matiz e L *, a * e b *), bem como parâmetros de produção: número total de frutas, produção total de frutas, massa média de frutas, produção de frutas não comerciais, produção comercial de frutas e produtividade total. A cultivar Camarosa de origem nacional, quando cultivada em cascas de arroz queimadas+composto orgânico, apresentou os melhores resultados de produção e qualidade dos frutos.

ABSTRACT The production and quality of strawberries may vary according to cultivar, transplant origin, and the system of plant cultivation. The objective was to evaluate the effect of different organic substrates and different transplant origins on strawberry production and fruit quality. The experiment was conducted in a randomized complete block design with a 2x2x4 factorial scheme using two cultivars (Albion and Camarosa) obtained from different origins (National-Brazilian and Imported-Argentine) and four combinations of substrates: (crushed sugarcane bagasse [70%] + organic compost [30%], crushed sugarcane bagasse [70%] + Carolina® commercial substrate [30%], burnt rice husks [70%] + organic compost [30%], and burnt rice husks [70%] + Carolina® commercial substrate [30%]). The experimental unit was composed of eight plants, with repetition in four blocks. The quality parameters of titrable total acidity, total soluble solids, ratio of sugar / acidity, firmness, and pulp coloration (chroma, hue angle, and L*, a* and b*) were evaluated, as were the production parameters of total number of fruits, total fruit production, average fruit mass, non-commercial fruit production, commercial fruit production and total productivity. The substrate influences the strawberry production variables. Fruit yield was highest in the Camarosa cultivar grown on the S3 substrate mixture. The cultivar, the transplant origin and the cultivation substrate influence fruit AT. SST and AT / SST are influenced only by cultivar and transplant origin. Chroma differs between plants with different transplant origins. Camarosa of National origin cultivated in burnt rice husks + organic compost presented the best production results and fruit quality.

Os modelos de simulação são ferramentas utilizadas na área de agrometeorologia para quantificar o desenvolvimento de culturas agrícolas e florestais. O trabalho teve como objetivo comparar os modelos do Filocrono (linear) e de Wang e Engel (não linear) para estimar o desenvolvimento foliar, através do aparecimento de folhas, nas cultivares de oliveira 'Arbequina' e 'MGS ASC315' durante a fase de muda. O experimento foi instalado no campo experimental da Empresa Agropecuária de Minas Gerais (EPAMIG), Maria da Fé (MG), sob o delineamento inteiramente casualizado e organizado em arranjo fatorial, sendo duas cultivares e nove épocas de transplantio com 15 repetições em cada tratamento. Os coeficientes dos modelos foram estimados pelos dados obtidos nas três primeiras épocas de transplantio e as demais épocas foram utilizadas para avaliar o desempenho dos modelos. As respostas dos modelos foram divergentes para os dois modelos. O modelo de Wang e Engel foi mais eficiente para a cultivar 'Arbequina', com raiz do quadrado médio do erro (RQME) de 3,41 folhas, enquanto a cultivar 'MGS ASC315' teve a RQME de 6,58 folhas. O modelo do Filocrono se mostrou mais eficiente para a cultivar 'MG ASC315' com RQME de 2,98 folhas, inferior ao da cultivar 'Arbequina', com RQME de 7,49 folhas.

Simulation models are tools used in the Agrometeorology to quantify the development of agricultural and forest crops. The aim of this work was to evaluate and compare the Phyllochron (linear) and the Wang and Engel (non-linear) models for estimating the leaf development, by leaf appearance, in two olive cultivars during the seedling phase. A field experiment was carried out in the Agricultural Company of Minas Gerais (EPAMIG), Maria da Fé (MG). The experimental design was completely randomized in a factorial arrangement, with two cultivars, nine planting dates and 15 repetitions in each treatment. The three first planting dates were used to estimate the models coefficients and other planting dates were used as independent data to evaluate the models. The response was different for the two cultivars. The Wang and Engel model estimations performed better for 'Arbequina', with a Root Mean Square Error (RMSE) of 3.41 leaves while the Phyllochron model better estimated for 'MGS ASC315'with RMSE of 2.98 leaves, below the one obtained for the 'Arbequina' cultivar with a RMSE of 7.49 leaves.

O objetivo foi estabelecer um protocolo para indução de embriogênese somática em Anthurium andraeanum cv. Eidibel. O experimento foi arranjado em delineamento inteiramente casualizado, com esquema fatorial 5 x 5 x 5, cinco explantes (folha inteira e seccionada ao meio; pecíolo; segmento nodal e de raiz); cinco auxinas (AIA, ANA, AIB, 2,4-D e Picloram) em cinco concentrações (0,0; 2,5; 5,0; 7,5 e 10 µM) e cinco repetições, consistindo de cinco placas de Petri, mantidas em sala de crescimento a 25 ± 2 ºC, no escuro. Após 60 dias de cultivo, a maior produção de calos embriogênicos foi registrada nos segmentos nodais cultivados na presença de ANA (5; 7,5 e 10 µM), 2,4-D (10 µM) ou Picloram (7,5 e 10 µM). As análises histológicas confirmaram a presença de embriões com polaridade definida, procâmbio, meristema fundamental e protoderme em segmentos nodais cultivados em meio Pierik com 10 µM ANA. Depois da conversão dos embriões somáticos, as plantas foram aclimatizadas e transferidas para as condições in vivo, com crescimento normal das mesmas.

This study establishes a protocol for the induction of somatic embryogenesis in Anthurium andraeanum cv. Eidibel. The experiment was arranged in a completely randomized 5 x 5 x 5 factorial design using five explant types (whole leaves, half leaves; petiole; nodal segments and root segments) from in vitro plantlets; five auxins: indole-3-acetic acid (IAA), α-naphthaleneacetic acid (NAA), indole-3-butyric acid (IBA), 2,4-dichlorophenoxyacetic acid (2,4-D), and 4-amino-3,5,6-trichloropicolinic acid (Picloram); at five concentrations (0, 2.5, 5, 7.5 and 10 µM), with five replications using five Petri dishes. The cultures were maintained in a growth room at 25 ± 2ºC in the dark. The explant type was investigated for the induction of somatic embryogenesis in anthurium cv. Eidibel, and nodal segments were shown to be the most suitable explant for this process. After 60 days in culture, the highest number of embryogenic calli was recorded for the nodal segments cultured in NAA (5, 7.5 and 10 µM), 2,4-D (10 µM) and Picloram

Os objetivos deste trabalho foram estabelecer in vitro as cultivares de oliveira 'Arbequina' e 'Maria da Fé' e avaliar a influência das tampas com membranas permeáveis a gases na morfogênese in vitro dessas cultivares. Inocularam-se segmentos nodais com gemas previamente descontaminadas pelo protocolo aqui desenvolvido. Utilizaram-se o delineamento inteiramente casualizado (DIC) em esquema fatorial 2³, duas cultivares; dois meios de cultura OM (Olive medium) (OM + 20 µM de zeatina [1]; e OM + 20 µM de zeatina + 10 µM de GA3 [2]); dois tipos de vedação (tampa rígida sem orifício e com membrana porosa) com cinco repetições/ tratamento; e a unidade experimental constituída por quatro tubos de ensaio. Avaliaram-se: a porcentagem de contaminação total; a porcentagem de contaminação fúngica e bacteriana; o número de gemas intumescidas; o número de brotos; e a porcentagem de oxidação. Aos 30 dias de cultivo, constatou-se a contaminação de 15% e 8,8% dos explantes de 'Arbequina' e 'Maria da Fé', respectivamente. Em 'Arbequina', 33,3% e 66,7% ocorreram por contaminação fúngica e bacteriana, respectivamente. Em 'Maria da Fé', 28,6% e 71,4% decorreram de contaminação fúngica e bacteriana, respectivamente. O número de gemas foi superior (p<0,05) em 'Arbequina', comparativamente à 'Maria da Fé', quando se utilizou tampa com membrana porosa para vedar os frascos. Em tampa rígida não houve diferença entre cultivares. O número de brotos no meio 1 foi superior estatisticamente (p<0,05) ao no meio 2. Não houve diferença estatística em porcentagem de oxidação. Sugere-se a utilização do protocolo de desinfestação aqui desenvolvido, como também do meio 1 e tampas com membranas porosas, pois isso favorecerá o desenvolvimento das gemas e a posterior formação de plantas.

The objectives of this work were to establish cultivars of Olea europaea L., namely 'Arbequina' and 'Maria da Fé', and to evaluate the influence of gas exchange on in vitro morphogenesis of these cultivars. Under aseptic conditions, single-bud nodal segments were previously decontaminated using disinfestation protocol developed in this work. The treatments followed a completely randomized design, in a 2³ factorial scheme: two cultivars and two olive (Olive medium) culture media (OM) (OM + 20 µ M zeatin [1]; and OM + 20 µ M zeatin + 10 µM GA3 [2]); and two types of sealing (rigid lid without orifice and porous membrane) in five repetitions/treatment. The experimental unit consisted of four tubes. The following parameters were assessed: percentage of total contamination; percentage of fungal and bacterial contamination; number of explants with swollen buds; number of axillary buds, and oxidation percentages. At 30 days of cultivation, the total contamination indexes of 15% and 8.8% were recorded for 'Arbequina' and 'Maria da Fé', respectively. For bacterial and fungal contamination percentages, respectively, 'Arbequina' had 33.3% and 66.7%, whereas 'Maria da Fé' presented 71.4% and 28.6%. Regarding the number of responsive cultures showing swollen buds, there was no difference between cultivars when rigid lids without porous membranes were used. However, lids with porous membranes led to statistically superior values for 'Arbequina' as compared to 'Maria da Fé'. For the number of shoots, culture medium 1 was statistically superior to 2. There was no statistical difference for oxidation percentages among treatments. Thus, because of the low level of contamination, it is suggested to use the disinfestation protocol developed in this work. In addition, the use of culture medium 1 and lids with porous membranes did favoured further development of axillary buds into plants.