Resumen Syagrus schizophylla es una especie de palmera ornamental en peligro de extinción. El objetivo de esta investigación fue estudiar los aspectos fisiológicos del crecimiento y la calidad de las plantas producidas bajo gradientes de luz. Los tratamientos de gradientes de luz fueron: G1 - PAR = 1234.10 μmol fotones m-2 s-1, G2 - PAR = 913.16 μmol fotones m-2 s-1, G3 - PAR = 666.34 μmol fotones m-2 s-1), G4 - PAR = 419,56 μmol fotones m-2 s-1 y G5 - PAR = 534,77 μmol fotones m-2 s-1. Antes de aplicar los tratamientos y a los tres, cinco y siete meses de tratamiento, se analizaron la altura de la planta, diámetro del collar, número de hojas, largo del pecíolo, largo y ancho de la hoja), intercambio gaseso, fluorescencia de la clorofila a y color verde de la hoja. Las tasas fotosintéticas netas más altas se observaron en plantas bajo G2, G3 y G4. Em G2 se observaron valores de Fv/Fm superiores a 0,75. En el séptimo mes, los valores estimados del índice SPAD fueron 36 en plantas bajo G2 y 32 en plantas bajo G1. El mejor crecimiento y desarrollo de las plantas se observó en G2 de acuerdo con DQI que muestra que este gradiente debe usarse para plantas destinadas al campo, mientras que G3 sería mejor para plantas destinadas a entornos sombríos.

Abstract This research studied growth and yield of Syagrus schizophylla, an extinction-endangered ornamental palm, grown under five light gradients. The treatments were: G1 - PAR=1234.10 μmol photons m-2 s-1, G2 - PAR=913.16 μmol photons m-2 s-1, G3 - PAR=666.34 μmol photons m-2 s-1, G4 - PAR=419.56 μmol photons m-2 s-1 and G5 - PAR=534.77 μmol photons m-2s-1. Before the experiment and at three, five and seven months of treatment, growth (plant height, collar diameter, number of leaves, petiole length, leaf length and width), gas exchange, chlorophyll a, and leaf green color intensity were assessed. The highest net photosynthetic rates were observed in plants under G2, G3 and G4. Values of maximum quantum efficiency (F v /F m ) over 0.75 were observed under G2. At seven months, estimated SPAD values were 36 in G2 plants and 32 in G1 plants. According to the Dickson quality index (DQI), presented the highest growth and development rates. We conclude that G2 suits plants to be transplanted into the field, whereas G3 would be best for plants grown under shade environments.

Resumo Joannesia princeps, popularmente conhecida como cutieira, é uma Euphorbiaceae endêmica do Brasil, cuja madeira é utilizada para diversos fins industriais. As sementes possuem aproximadamente 37% de óleo útil para fins industrias e medicinais, servem de alimento para cutias (Dasyprocta azarae), além de apresentarem destacada importância na sucessão ecológica em áreas degradas. Objetivou-se estudar a germinação, fenologia e a morfometria de frutos, sementes e plântulas de Joannesia princeps. Foram utilizados 1000 frutos de Joannesia princeps colhidos de 40 matrizes de Mata Atlântica do Entorno do Caparaó, que compõem um bosque existente no Horto Municipal da cidade de Alegre - ES, nos quais foram analisados os atributos qualitativos em relação à morfologia. Na análise biométrica, foram analisados: comprimento, diâmetro e espessura. As análises das plântulas foram conduzidas periodicamente no 6°, 7º, 14º, 21º, 28º, 35º e 42º dia após a germinação, utilizando-se quatro repetições de 15 plântulas normais e sadias para as descrições. Observou-se que as raízes mudaram o tom de sua coloração de esbranquiçada para branco-amarelada entre o 14º para o 21º dia após a germinação (DAG), enquanto o hipocótilo, nos estádios iniciais, apresentava coloração avermelhada passando para verde após o 14º DAG. Os demais órgãos não apresentaram mudanças consideráveis, contudo, biometricamente, todos os órgãos apresentaram acréscimo nas suas dimensões, conforme a evolução do desenvolvimento. Os aspectos morfológicos descritos e ilustrados demonstraram-se estáveis e, portanto, informativos para a caracterização e identificação da espécie em processo de germinação e nos primeiros estádios de desenvolvimento.

Abstract Joannesia princeps, popularly known as a cutieira, is a Euphorbiaceae endemic to Brazil and its wood is used for various industrial purposes and the seed has approximately 37% of useful oil for industrial and medicinal purposes, besides presenting outstanding importance in ecological succession in degraded areas, whose seeds serve as food for agoutis. The objective was to study germination, phenology and morphometry of fruits, seeds and seedlings of Joannesia princeps. We used 1,000 fruits of Joannesia princeps harvested from 40 matrices of Atlantic Forest surrounding Caparaó, which make up an existing forest in the Municipal Garden of the city of Alegre, in Espírito Santo state, in which qualitative attributes were analyzed in relation morphology. In the biometric analysis, the following were analyzed: length, diameter and thickness and seedling analyses were conducted periodically on the 6th, 7th, 14th, 21th, 28th, 35th and 42th days after germination (DAG), using four replicates of 15 normal and healthy seedlings for descriptions. It was observed that the roots have changed their color of whitish for yellowish-white between the 14th and 21st DAG, while the hypocotyl, in the initial presented reddish color passing to green after the 14th DAG. The other organs did not present considerable changes, however, biometrically, all organs showed an increase in their dimensions, according to the evolution of development. The morphological features described and illustrated were stable, and therefore, informative for the characterization and identification of the species in the germination process and in the first stages of development.

Resumen Phoenix roebelenii es una especie de palma muy utilizada en Brasil debido a sus hojas exuberantes y su adaptabilidad a diferentes tipos de clima. Por esto, resulta importante obtener información detallada sobre la viabilidad, vigor y longevidad de sus semillas deshi dratadas y almacenadas. La presente investigación comprendió dos etapas. La primera tuvo como objetivo evaluar la respuesta de las semillas a la desecación y almacenamiento con base en protocolos formales. En la segunda, las semillas se desecaron hasta alcanzar el 33, 30, 25, 23, 20, 18, 16, 12, 10 y 7% de contenido de agua. Luego de alcanzar cada nivel de agua establecido para cada tratamiento, las semillas fueron sometidas a pruebas de germi nación. A los 65 días después de la siembra se midió: longitud del sistema radicular y del brote, el área, volumen y diámetro del sistema radicular, la longitud del eófilo y el peso fresco y seco de las plántulas. Por um lado, se observó un aumento significativo en el porcentaje de germinación y en la longitud del eófilo en función del menor contenido de agua de la semilla. Por otro lado, el diámetro del collar disminuyó como consecuencia de la desecación de la semilla.

Abstract Phoenix roebelenii is a palm species widely used in Brazil due to its exuberant leaves and adaptability to different climatic variations. For proper propagation, detailed information about seed viability, vigor and longevity subjected to dehydration and storage is yet to be obtained. For this purpose, the present research comprised two stages. The first one aimed at evaluating the response of seeds to desiccation and storage based on formal protocols. In the second stage, seeds were desiccated to 33, 30, 25, 23, 20, 18, 16, 12, 10 and 7% of water content by monitoring water loss in a convection oven at 35±2°C. After reaching each established water content, the seeds were subjected to germination tests. At 65 days after sowing, root length, root area, volume and diameter, shoot and eophyll length, and total seedling fresh and dry weights, were measured. Significant increases in germination and eophyll length were observed for lower seed water contents. Aversely, collar diameter decreased with seed desiccation.

Resumen El presente estudio evaluó el efecto de la inoculación de hongos micorrízicos arbuscu lares (AMF) en el crecimiento y la nutrición de plántulas de Euterpe edulis en ausencia y presencia de fertilización con fosfato. El experimento se realizó en invernadero. El diseño de bloques al azar, consistió en un arreglo factorial 3x2, con 4 repeticiones, dos dosis de fósforo (0 y 50 mg dm-3 de suelo), dos tratamientos microbiológicos (Rhizophagus clarus; Claroideoglomus etunicatum; R. clarus + C. etunicatum) y un testigo (sin hongos). La siembra y la inoculación ocurrieron simultáneamente en bolsas de plástico de 2 kg. Después de 226 días, se determinó altura, diámetro de cuello, área foliar, masa seca del brote, el contenido de macronutrientes y el porcentaje de colonización micorrízica. R. clarus resultó superior, considerándose entonces una especie fúngica beneficiosa para las plántulas de E. edulis. En ausencia de fertilización con fosfato, R. clarus y el inóculo mixto aumentaron todas las variables biométricas en comparación con el testigo. Además, se observó un aumento en el contenido de macronutrientes en las plántulas.

Abstract The present study evaluated the effect of arbuscular mycorrhizal fungi (AMF) inoculation on growth and nutrition of Euterpe edulis seedlings, supplemented or not with phosphate fertilization. The experiment was conducted in a greenhouse. The randomized block design, consisted of a 3x2 factorial arrangement and 4 replicates, with two phosphorus doses (0 and 50 mg dm-3 of soil), two microbiological treatments (Rhizophagus clarus; Claroideoglomus etunicatum; R. clarus + C. etunicatum) and control (without fungus). Sowing and inoculation occurred concurrently in 2 kg plastic bags. Height, collar diameter, leaf area, dry shoot mass, macronutrient content and mycorrhizal colonization percentage were determined after 226 days. Regarding mycorrhizal colonization percentage, R. clarus resulted significantly beneficial for the production of E. edulis seedlings. In the absence of phosphate fertilization, R. clarus and mixed inoculum increased all biometric variables and macronutrient contents in seedlings. Therefore, it is concluded that AMF inoculations provide beneficial effects for growth and nutrition of E. edulis seedlings, resulting in more vigorous plants at a low-cost strategy.

Sclerotium rolfsii, a widespread fungus in tropical and subtropical regions, is a phytopathogen that affects a large number of cultivated and wild plants-e.g. Brachiaria species-, causing plant damping-off events. Current disease control strategies include chemical treatment of seeds, genetic resistance and crop rotation. Compared to synthetic agrochemicals, silicon may induce plant resistance. This study examined the efficiency of calcium silicate in the coating of Brachiaria seeds on the incidence of the disease during plant germination and establishment. The experiment consisted of six Brachiaria brizantha seed-coating treatments involving different calcium silicate and sand proportions and two controls. The fungus was inoculated at three different times in relation to seed sowing: inoculation at sowing (IN0); inoculation 10 days after sowing (IN10); inoculation 20 days after sowing (IN20); and no inoculation (control). Radicle emergence, germination, abnormal seedlings, damped-off seedlings and dead seeds were evaluated. Increase in the germination rate of B. brizantha cv. MG5 seeds coated with calcium silicate was observed, which showed protective effect against the incidence of S. rolfsii, directly reflecting in lower damping- off percentages. The application of calcium silicate as coating provided protection to MG5 seeds and plants inoculated with S. rolfsii.

El hongo Sclerotium rolfsii es un fitopatógeno distribuido en regiones tropicales y subtropicales que infecta una gran cantidad de plantas cultivadas y silvestres, entre ellas la brachiaria, causando el vuelco. Las estrategias actuales de control de enfermedades implican el tratamiento químico de semillas, la resistencia genética y la rotación de cultivos. En este trabajo se evaluó la eficiencia del silicato de calcio en el recubrimiento de semillas de brachiaria bajo la incidencia de la enfermedad durante la germinación y el establecimiento de la planta. El experimento consistió en seis tratamientos de recubrimiento de semillas de Brachiaria brizantha con diferentes proporciones de silicato de calcio/arena y dos controles. La inoculación del hongo ocurrió en tres momentos diferentes en relación con la siembra de semillas: inoculación junto con siembra (IN0); inoculación 10 días después de la siembra (IN10), inoculación 20 días después de la siembra (IN20) y control no inoculado. Se evaluó emisión de radícula, germinación, plántulas anormales, plántulas caídas y semillas muertas. Germinación de B. brizantha cv. MG5 recubierto con silicato cálcico, que tuvo un efecto protector sobre la incidencia de S. rolfsii, reflejando directamente el menor porcentaje de inclinación de la planta.

Resumo As coroas de frutos de abacaxi são muito pouco utilizadas como material de plantio no Brasil. No entanto, podem servir para a produção de mudas em situações de escassez de material de plantio de qualidade adequada. O objetivo deste trabalho foi avaliar a produção e o estado nutricional de rebentos precoces de diferentes tamanhos produzidos em coroas de abacaxi com adubação nitrogenada bem como verificar as variáveis morfológicas e o estado nutricional das coroas de abacaxi da cv. Smooth Cayenne, após a extirpação do seu meristema apical. Ainda, avaliou-se o efeito de doses crescentes de adubo nitrogenado sobre o rendimento, vigor e qualidade nutricional das mudas. O delineamento experimental adotado foi o de blocos ao acaso em esquema fatorial 4x4, sendo quatro doses de nitrogênio (5, 10, 15 e 20 g de ureia por vaso), quatro comprimentos mínimos para colheita de rebentos (10, 15, 20 e 25 cm), com quatro repetições. Em condições de cultivo em pleno sol, as coroas produziram 18,11 e 6,83 rebentos com 10 e 25 cm de comprimento, respectivamente, até 380 dias após o plantio e extirpação do meristema apical. Os tamanhos de colheita dos rebentos influenciam sobre a massa seca da raiz e do caule das coroas. A adubação nitrogenada aumenta os teores de N e influencia negativamente os teores foliares de P, K, Ca e S das coroas do abacaxizeiro ‘Smooth Cayenne’.

Abstract Pineapple fruit crowns are rarely used as planting material in Brazil. However, they can be used to produce plantlet in situations of scarcity of planting material of adequate quality. The aim of this work was to evaluate the production and nutritional status of early shoots of different sizes produced from ‘Smooth Cayenne’ pineapple crowns with nitrogen fertilization after the removal of its apical meristem. The experimental design adopted was that of randomized blocks in a 4x4 factorial scheme, with four nitrogen doses (5, 10, 15 and 20 g of urea per pot), four minimum shoot lengths at harvesting (10, 15, 20 and 25 cm), with four replicates. Under full sun cultivation conditions, crowns produced 18.11 and 6.83 shoots with 10 and 25 cm in length, respectively, up to 380 days after planting and removal of the apical meristem. Pineapple shoots harvested at 180 days presented better biometric quality and can be harvested up to 380 days after crown planting. Increasing urea doses reduce P, K and Ca levels in the dry mass of shoots.

RESUMO Objetivou-se analisar a distribuição espacial dos atributos que determinam a qualidade fisiológica de sementes de Joannesia princeps. As sementes foram coletadas, individualmente, de 40 plantas matrizes no Horto Florestal Municipal Laerth Paiva Gama, em Alegre-ES, que constituíram a malha amostral georreferenciada. Para a germinação, as sementes tiveram o tegumento trincado e foi realizada a embebição em solução de ácido giberélico GA3 500 mg L-1 durante 24 h em câmara tipo BOD a 30 ºC. A semeadura foi realizada em sacos plásticos de ± 600 cm3 contendo terra+areia+esterco na proporção de 1:1:1. No 65º dia após a semeadura foram avaliadas as seguintes variáveis: emergência (E), índice de velocidade de emergência (IVE), comprimento da raiz (CR), diâmetro do coleto (DC), comprimento da parte aérea (CPA), massa fresca do sistema radicular (MFSR), massa fresca da parte aérea (MFPA), massa seca do sistema radicular (MSSR) e massa seca da parte aérea (MSPA). Os dados foram submetidos à análise estatística descritiva, geoestatística e interpolação por krigagem. Com exceção do CPA e da MFSR, verificou-se dependência espacial para as demais variáveis estudadas: E, IVE, CR, DC, MFSR, MFPA, MSSR e MSPA; com alcance variando de 14,0 a 47,5 m, sendo o menor alcance obtido para o CR e o maior alcance e grau de dependência espacial para o IVE. A análise da distribuição espacial da qualidade fisiológica de sementes de J. princeps pode ser utilizada como uma ferramenta para definição da região de amostragem de sementes com alto e baixo vigor.

ABSTRACT The objective of this study was to analyze the spatial distribution of the attributes that determine the physiological quality of Joannesia princeps seeds. Seeds were collected, individually from, 40 mother plants in the Horto Florestal Municipal Laerth Paiva Gama, in Alegre-ES, which constituted the georeferenced sampling mesh. For germination, the seeds tegument was cracked and was held the imbibition in gibberellic acid GA3 500 mg L-1 for 24 h in environmental chamber with temperature adjusted to 30 ºC. The seeds were sown in plastic bags of ± 600 cm3 containing soil+sand+manure in the proportion of 1:1:1. On the 65th day after sowing, the following variables were analised: emergence (E), emergence speed index (IVE), root length (CR), diameter of base (DC), shoot length of the aerial part (CPA), fresh mass of the root system (MFSR), fresh mass of the aerial part (MFPA), dry mass of the root system (MSSR) and dry mass of the aerial part (MSPA). Data were subjected to descriptive statistics, geostatistics and kriging. With the exception of CPA and MFSR, it was found spatial dependence for the other studied variables: E, IVE, CR, DC, MFPA, MSSR e MSPA; varying of 14,0 a 47,5 m, so that the lowest range for the CR and longer range and degree of spatial dependence for the IVE. The analysis of the spatial distribution of the physiological quality of seeds of J. princeps can be used as a tool to define the sampling region of seeds with high and low vigor.