ABSTRACT. The aim of the study was to assess the effect of plant regulators (gibberellic acid and naphthalene acetic acid) and adjuvant LI 700® with and without hand pollination on the fruiting and quality of Annona squamosa L. cultivars. The experiment was conducted in the experimental orchard of the Florida Tropical Research and Education Center (TREC/UF) in Homestead, Florida, USA. The experimental design in random blocks comprised 14 treatments, 10 repetitions and 3 flowers per treatment and per tree for ‘Red’ and ‘Lessard Thai’ cultivars. To assess quality, 9 fruit from each treatment were used, with 3 repetitions and 3 fruit per repetition. High instability was observed in fruit fixation rates between cultivars. The application of growth regulators did not increase fruit fixation in the tested cultivars. The application of naphthalene acetic acid had a deleterious effect on the flowers of the sugar apple cultivars. The most uneven (asymmetrical) fruit was obtained in the treatments with the application of growth regulators. The application of the adjuvant showed toxicity, causing damage to the skin of the fruit. The fruit with the greatest symmetry had the lowest levels of soluble solids and the highest toxicity. The application of growth regulators associated with hand pollination was not efficient, presenting a low percentage of fruit fixation for Annonaceae cultivars. None of the studied treatments produced parthenocarpic fruit (without seeds). The utilization of an adjuvant in the applied concentration caused damage to the fruit peels (darkening) due to toxicity in both cultivars.

RESUMO Objetivou-se verificar a qualidade fisiológica de sementes de Myrciaria dubia, armazenadas em diferentes ambientes e embalagens durante 300 dias, a partir dos testes de condutividade elétrica, e vigor das plântulas. As sementes foram armazenadas dentro de embalagem de vidro e potes plásticos com água até à superfície do recipiente, no laboratório à temperatura ambiente entre 23 a 25°C e 60-70% UR e em câmara fria à temperatura entre 14-16°C e 50-60% UR. A cada período de armazenamento (0, 30, 60, 120, 180, 240 e 300 dias), foi retirada, de cada recipiente, uma amostra de 110 sementes e submetida às seguintes avaliações: curva de embebição de água, massa seca de sementes, teste de condutividade elétrica, emergência de plantulas e índice de velocidade de emergência. De acordo com os resultados, verificou-se que o armazenamento das sementes de Myrciaria dubia em potes plásticos com água até superfície do recipiente, quer no laboratório e quer na câmara fria, foi indicado para manter a qualidade fisiológica e vigor de plântulas até 300 dias.

ABSTRACT The study aimed to verify the physiological quality of seeds of Myrciaria dubia, stored for 300 days in different conditions and packaging, using tests of electrical conductivity and seedling vigour. The seeds were classified into three weight classes (small, medium and large). Small seeds were considered those with a weight of less than 0.84 g, medium seeds with a weight between 0.86 g and 1.20 g, and large seeds, a weight of greater than 1.22 g. The seeds were stored in glass containers and plastic pots topped up with water, in the laboratory at a room temperature of 23 to 25°C and relative humidity of 60-70%, and in a cold chamber at a temperature of 14-16°C and relative humidity of 50-60%. For each storage period (0, 30, 60, 120, 180, 240 and 300 days), a sample of 110 seeds was used for analyses, including imbibition curve, seed dry weight, electrical conductivity, seedling emergence and emergence speed index. According to the results obtained, the responses of the seeds in both the laboratory and cold-chamber, and stored in plastic pots topped up with water, were indicated for maintaining physiological quality and seedling vigour up to 300 days.

Abstract Due to limited information on sweet potato (Ipomoea batatas L.) cultivation in uncultivated savanna areas, the objective of this research was to determine the ideal dose and type of organic fertilizer for sweet potato cultivation in savanna soils with no history of use. In four experiments, the following fertilizer doses were tested: cattle manure (0, 10, 20, 30, and 40 t·ha-1), poultry manure (0, 5, 10, 15, and 20 t·ha-1), compost A (0, 0.75, 1.5, 2.25, and 3.0 t·ha-1), and compost B (0, 0.75, 1.5, 2.25, and 3.0 t·ha-1). The fifth experiment consisted of an organic fertilizer efficiency test using applications already recommended for sweet potato crops, which resulted in six treatments: control (without organic fertilization), cattle manure (20 t·ha-1), poultry manure (10 t·ha-1), compost A (1.5 t·ha-1), compost B (1.5 t·ha-1), and compost C (0.375 t·ha-1). In the first four experiments, the products and their recommended doses were defined in order of production efficiency, as follows: poultry manure (doses between 13 and 20 t·ha-1) > cattle manure (doses between 30 and 40 t·ha-1) > compost B (doses between 0.75 and 2.25 t·ha-1) = compost A (doses between 2.25 and 3.00 t·ha-1). The fifth experiment concluded that: 1) poultry manure was the most suitable starting point for sweet potato cultivation in savanna soils and 2) sweet potato yield was directly linked to the commercial root mass, number of commercial roots, and branch productivity, which, in turn, were maximized by an increase in organic matter and satisfactory amounts of phosphorus in the soil.

Resumen Debido a la limitada información sobre el cultivo de camote (Ipomoea batatas L.) en áreas silvestres de la sabana, el objetivo de este estudio fue determinar la dosis ideal y el tipo de fertilizante orgánico para el cultivo de camote en suelos de la sabana sin antecedentes de explotación. Se probaron diferentes dosis de fertilizantes en cuatro experimentos: estiércol de ganado (0, 10, 20, 30 y 40 t·ha-1), pollinaza (0, 5, 10, 15 y 20 t·ha-1), compost A (0, 0.75, 1.5, 2.25 y 3.0 t·ha-1) y compost B (0, 0.75, 1.5, 2.25 y 3.0 t·ha-1). El quinto experimento consistió en una prueba de eficiencia de fertilizantes orgánicos utilizando dosis recomendadas para el cultivo de camote, lo cual resultó en seis tratamientos: testigo (sin fertilización orgánica), estiércol de ganado (20 t·ha-1), pollinaza (10 t·ha-1), compost A (1.5 t·ha-1), compost B (1.5 t·ha-1) y compost C (0.375 t·ha-1). En los primeros cuatro experimentos, los productos y dosis recomendadas se definieron en orden de eficiencia de producción: pollinaza (dosis entre 13 y 20 t·ha-1) > estiércol de ganado (dosis entre 30 y 40 t·ha-1) > compost B (dosis entre 0.75 y 2.25 t·ha-1) = compost A (dosis entre 2.25 y 3.00 t·ha-1). Con el quinto experimento se concluyó que: 1) la pollinaza fue el fertilizante inicial más adecuado para el cultivo de camote en suelos de la sabana y 2) el rendimiento del camote estuvo vinculado directamente a la masa de las raíces comerciales, el número de raíces comerciales y la productividad de tallos; las cuales, a su vez, fueron maximizadas al incrementar la materia orgánica y las cantidades de fósforo en el suelo.

ABSTRACT. In vitro culture systems based on liquid culture media are considered to be more effective than semisolid culture medium systems. Liquid culture media systems provide better nutrient availability for plant tissues, easier culture handling, and the potential for scaling up and automation. However, in vitro liquid culture requires more careful handling due to the potential for contamination and the possibility of negative effects, such as hyperhydricity or vitrification, that hinder the growth and development of the plant material. Temporary immersion bioreactors have emerged as a workable alternative for capturing the benefits of liquid media, though semisolid systems are still traditional. Many studies have shown that silicon (Si) is a beneficial plant nutrient. Silicon might have a positive effect in both semisolid and liquid in vitro systems. The objective of this study was to evaluate the effect of silicon on the micropropagation and acclimatization of banana plants cultivated in vitro by comparing liquid temporary immersion bioreactor technology and semisolid traditional culture systems. Different silicon concentrations (0 and 1 mL L-1) and culture systems (liquid temporary immersion bioreactor and semisolid traditional culture) were evaluated over a 36-day period. The growth characteristics plant size, fresh and dry weight, and number and length of leaves and roots were evaluated. After the 36-day in vitro growth period, plants were transferred to a greenhouse for acclimatization and were evaluated after 30 days for the same growth characteristics used in the in vitro studies. The temporary immersion bioreactor system resulted in greater growth of banana plants compared to the traditional semisolid system. Temporary immersion bioreactors also showed a positive interaction with Si and resulted in higher values for all growth characteristics in the acclimatization phase.

ABSTRACT. Sugar apples have attracted attention in recent years due to their medicinal and nutritional properties. However, the shelf life of sugar apples is one of the most concerning problems owing to their perishability. This work aimed to determine the ideal harvest time for sugar apple fruits in relation to different classes of carpel interspaces. Therefore, fruits were classified into three stages according to the carpel interspace: stage 1 (0.0 - 2.0 mm); stage 2 (2.1 - 3.0 mm); and stage 3 (3.0 - 4.0 mm). After harvesting, the fruits were evaluated daily in the laboratory regarding their physical and physicochemical aspects until they reached the point of consumption (horticultural maturation). The following variables were evaluated: fruit diameter and length (mm); fruit, peel, pulp, and seed masses (g); color index, including the chromatic attributes L* (luminosity), C* (chroma), and h* (hue angle); bark firmness (N); soluble solids (°Brix); titratable acidity (g citric acid 100 g-1 of pulp-1); pulp yield; and ratio SS/TA. Fruits at stage 3 showed larger diameters, less firmness, and better chromaticity means. Fruits at stages 2 and 3 had eight days of postharvest life. However, fruits at stage 2 took longer for 50% of the fruits to be ready for consumption. The results demonstrate that stages 2 and 3 can be determinants for the harvest time of sugar apples.

Abstract: Caçari is a fruit tree that is native to the Amazon region of Brazil. The fruit is considered to have the highest vitamin C content of any edible fruit (13.757 mg 100 g-1 dry weight). The objective of this study was to evaluate the effects of 2,4-D and 6-BAP alone or in combination on in vitro callus induction and pro-embryogenic mass formation in caçari stem segments in different culture media as a precursor for caçari micropropagation. The experiment consisted of two culture media (MS and WPM) and combinations of four concentrations of 2,4-D (0, 1, 2 and 4 mg L-1) and BAP (0, 0.25, 0.5 and 1 mg L-1). The results showed that the highest percentage of callus formation (99%) was obtained in WPM supplemented with 4 mg L-1, 2,4-D and 1 mg L-1 BAP, and this combination resulted in 93% pro-embryogenic mass formation.

ABSTRACT. The present study was carried out to evaluate the antioxidant activity of and the content of bioactive compounds in camu-camu fruits harvested at different maturation stages and stored. The fruits were harvested in the municipality of Cantá, Roraima State, Brazil. The experimental design was completely randomized, with three replications, in a factorial arrangement consisting of three different maturation stages (immature, semi-mature and mature) and eight days of storage (3 x 8). The fruits were analysed every day regarding total vitamin C, carotenoids, anthocyanins, flavonoids, total phenolic compounds, and antioxidant activity (FRAP and DPPH). According to the results obtained, the interaction of maturation stages x eight days of storage had a significant effect according to the F test at 5% probability. The highest antioxidant activity (FRAP) was observed in the fruits harvested in the semi-mature stage, providing a longer shelf life. The carotenoid pigment, flavonoid, anthocyanin, and vitamin C contents were higher in the fruits harvested in the mature stage, and this stage was the most suitable for obtaining these functional biocompounds. Additionally, in mature fruits, the highest mean content of total phenolics and antioxidant activity (DPPH) were observed during storage. It was concluded that the mature stage is the most recommended for the extraction of pigments and antioxidant biocompounds from camu-camu fruits.

Abstract Myrciaria dubia (Kunth) McVaugh is a fruit tree native to the Amazon with great potential due to its nutraceutical properties; thus, ex situ adaptation technologies should be developed. The objective of this study was to determine the evapotranspiration (ETc) and crop coefficient (Kc) of Myrciaria dubia for domestication and conservation on uplands. Two Myrciaria dubia plants of 2, 4, and 6 years old with similar morphological characteristics of height, number of branches (basal and terminal), and diameter (stem and canopy) were transplanted into drainage lysimeters. Residue of organic mulching composed of a native grass (Trachypogon plumosus) was applied once to one plant of each age category. The mean ETc values for 2-, 4-, and 6-year-old plants in the presence and absence of mulch were 2- and 2.7-mm·day-1, 3.2- and 3.9-mm·day-1, and 6.1- and 7.2-mm·day-1, respectively. The mean Kc values in the EI, EII, and EIII phenological stages with and without mulch were 0.4 and 0.6, 0.6 and 0.8, and 1.1 and 1.3, respectively. The ETc and Kc values for Myrciaria dubia plants with organic mulching can be used in irrigation planning for cultivation, domestication, conservation, and efficient use of water resources in tropical savannas of Roraima, Brazil.

Resumen Myrciaria dubia (Kunth) McVaugh es un árbol frutal nativo de la Amazonía con gran potencial debido a sus propiedades nutracéuticas, por lo que se considera necesario desarrollar tecnologías de adaptación ex situ. El objetivo de este estudio fue estimar la evapotranspiración (ETc) y el coeficiente de cultivo (Kc) de Myrciaria dubia para su domesticación y conservación en suelos de tierra firme. Se trasplantaron, a lisímetros de drenaje, dos plantas de Myrciaria dubia de 2, 4 y 6 años de edad con características morfológicas similares en altura, número de ramas (basales y terminales) y diámetro (de tallo y dosel). Se aplicó, a una planta de cada categoría de edad y en una ocasión, acolchado orgánico compuesto de una hierba nativa (Trachypogon plumosus). Los valores promedio de la ETc de las plantas de 2, 4 y 6 años de edad en presencia y ausencia de acolchado fueron 2 y 2.7 mm·día-1, 3.2 y 3.9 mm·día-1, y 6.1 y 7.2 mm·día-1, respectivamente. Los valores promedio del Kc en las etapas fenológicas EI, EII y EIII, con y sin acolchado, fueron 0.4 y 0.6, 0.6 y 0.8, y 1.1 y 1.3, respectivamente. Los valores de la ETc y el Kc de las plantas de Myrciaria dubia con acolchado orgánico se pueden utilizar en la planificación del riego, la domesticación, la conservación y el uso eficiente de los recursos hídricos en las sabanas tropicales de Roraima, Brasil.

Abstract The camu-camu tree (Myrciaria dubia (Kunth) Mc Vaugh) is fruit-bearing tree belonging to the family Myrtaceae. This work was conducted with the purpose of evaluating the type of storage temperature and package which allow better conservation of the quality attributes of camu-camu. The experimental design utilized was the completely randomized with three replications in a factorial arrangement (3x3x8), constituted of three different storage temperatures (laboratory ambiente or 25 ± 2 °C, 15 °C and 20 °C), three types of packages (no package, PET and PVC) and fourteen days’ storage, the fruits being analyzed every two days. The fruits were evaluated as to fresh mass loss, pH, soluble solids contents, titrable acidity, ascorbic acid, carotenoids, anthocyanins, chlorophylls A and B and maturation index (SS/AT). According to the results obtained, the quality attributes and ascorbic acid content were conserved for longer time in the fruits stored on PVC-film covered expanded polystyrene trays at 15 °C. It follows that the best temperature for the storage of camu-camu is 15 °C and the package that best keeps its quality attributes is the PVC-film covered expanded polystyrene tray.

Resumo Como a maioria dos programas de melhoramento de espécies nativas, o camu-camu (Myrciaria dubia (Kunt) McVaugh), apresenta limitações pelas escassas experiências de pesquisas. Dessa forma, a prospecção, coleção e conservação através dos Bancos de Germoplasma são uma garantia para a realização de trabalhos de seleção e melhoramento da espécie. Neste sentido, objetivou-se com o presente trabalho realizar a caracterização intraespecífica da variabilidade biométrica em frutos de populações nativas de camu-camu, prospectados no estado de Roraima, Amazônia Setentrional. Foram avaliados 247 subamostras provenientes de 16 populações. As análises foram realizadas com auxilio da técnica multivariada de componentes principais e de agrupamento hierárquico. As análises permitiram determinar as variáveis que aportaram à maior variabilidade intraespecífica nas características avaliadas. As populações oriundas da região do baixo rio Branco apresentaram os maiores atributos nas características avaliadas, representando uma região com grande potencialidade na obtenção de subamostras promissores para futuros planos de melhoramento da espécie na Amazônia Setentrional.

Abstract Similarly to most breeding programs of native species, camu-camu (Myrciaria dubia (Kunt) McVaugh) improvement is also restricted, due to the scarcity of research results. In this situation, the prospection, collection and conservation of germplasm in genebanks ensure successful selection and breeding studies of the species. In this sense, the purpose of this study was the intraspecific characterization of the biometric variability in fruits of native camu-camu populations of the State of Roraima, in the northern Amazon region. Of 16 populations, 247 sub-samples were evaluated. Analyses were performed with the multivariate technique of principal components and hierarchical clustering, to determine the variables with highest intraspecific variability for the studied traits. The populations found in the lower Rio Branco region performed best for the studied traits, indicating the great potential of the region as a reservoir of promising subsamples for future breeding programs of the species in the northern Amazon.

Objetivou-se avaliar o desempenho adaptativo, produtivo e atributos de qualidade de cultivares de macieira nas condições subtropicais da região leste paulista. Para tal, um ensaio de competição de cultivares foi implantado no município de Jundiaí, SP, com sete cultivares ('Eva', 'Condessa', 'Princesa', 'Rainha', 'Imperial Gala', 'Daiane', e 'Baronesa'). O experimento foi implantado em 2006, no espaçamento de 3,0mx1,5m, com mudas enxertadas no porta-enxerto Marubakaido e interenxerto M9. As avaliações foram realizadas em dois ciclos produtivos (2008/09 e 2009/10), analisando-se os aspectos fenológicos, produtivos e atributos de qualidade do fruto. As cultivares de macieira 'Eva', 'Baronesa' e 'Princesa' apresentaram maior produção de frutos. A cultivar 'Baronesa' apresentou atributos de qualidade mais adequados ao consumo ao natural, com menor acidez titulável e boa firmeza de polpa e ratio mais elevado.

These research aimed evaluate the production and quality attributes of apple tree cultivars in subtropical conditions at eastern of São Paulo state. For such, an assay of competition among cultivars was implanted in the Jundiaí city, SP, with seven cultivars ('Eva', 'Condessa', 'Princesa', 'Rainha', 'Imperial Gala', 'Daiane', and 'Baronesa'). The experiment was implanted in 2006, the spacing was 3,0mx1,5m, and the plants were grafting in Marubakaido roostock and M9 inter-grafting. The evaluations had been carried through in two production cycle (2008/09 and 2009/10), the phenological stage, productive aspects and fruit quality attributes were evaluated. 'Eva', 'Baronesa' and 'Princesa' showed higher productive performance. The 'Baronesa' apple presented fruit quality attributes most suitable for the fresh market, i.e., lower acidity and good firmness, and the highest ratio.

Considerando a baixa produção dos marmeleiros em regiões de inverno ameno, o presente trabalho foi desenvolvido com o intuito de selecionar cultivares produtivas para o Estado de São Paulo. Plantas de três anos de idade dos marmeleiros 'Marmelo Pera', 'Smyrna', 'Cheldow', 'Van Deman', 'Meliforme', 'Portugal', 'Provence', 'Mendoza Inta-37', 'Rea´s Mamouth', 'Fuller', 'Meech Prolific', 'De Patras' e 'Pineapple', cultivadas no Centro APTA de Frutas do IAC (Jundiaí-SP), em espaçamento 3 x 4 m, foram avaliadas nas safras 2008/09 e 2009/10. Durante as duas safras, foram avaliadas as fases fenológica, número médio de frutos, produção média e produtividade estimada, massa, diâmetro e comprimento médio de frutos, coloração da epiderme e polpa, firmeza da polpa, sólidos solúveis, acidez titulável e relação SS/AT. Concluiu-se que os marmeleiros 'Fuller', 'Smyrna', 'Portugal', 'Provence' e 'Mendoza Inta-37' apresentaram maior desempenho produtivo. A cultivar Mendoza Inta-37 apresentou atributos de qualidade mais adequados ao consumo in natura, com maior teor de sólidos solúveis, menor acidez titulável e firmeza de polpa e ratio mais elevado, seguida pelos marmeleiros 'Fuller', 'Provence' e 'Portugal'.

Considering the low average production of quince tree in subtropical regions, the present study was developed in order to select productive cultivars for São Paulo state. Plants of three years of quince tree 'Marmelo Pêra', 'Smyrna', 'Cheldow', 'Van Deman', 'Meliforme', 'Portugal', 'Provence', 'Mendoza Inta-37', 'Rea´s Mamouth', 'Fuller', 'Meech Prolific', 'De Patras' and 'Pineapple', located at the Fruit Center APTA, Agronomic Institute (Jundiaí/SP, Brazil) in a spacing of 3 x 4 m, were evaluated in 2008/09 and 2009/10 crop years. During the two seasons were measured phenological description, average number of fruit, average and estimated yield, mass, diameter and length of the fruit, skin and pulp color, flesh firmness, total soluble solids, titratable acidity and the ratio SS/TA. It was concluded that the quince 'Fuller' 'Smyrna', 'Portugal', 'Provence', and 'Mendoza Inta-37' showed higher productive performance. The quince 'Mendoza Inta-37' showed quality attributes most suitable for the fresh market, i.e., higher soluble solids content, lower acidity and firmness, and the highest ratio, followed by quince 'Fuller', 'Provence', and 'Portugal'.

O ensacamento é uma operação de extrema importância no cultivo da nespereira por proporcionar qualidade à colheita de frutas, além de permitir uma minimização na utilização de produtos químicos. Entretanto, ainda existe carência de informações quanto ao momento adequado de realizar a operação, principalmente considerando-se o estádio limite de ensacamento em que se podem obter frutos de qualidade comercial. Em função do exposto, objetivou-se avaliar a qualidade dos frutos ensacados de cultivares de nespereiras em diferentes estádios. Avaliaram-se as cultivares 'Mizuho', 'Mizumo', 'Mizauto', 'Centenária', 'Néctar de Cristal' e a seleção IAC NE-3 a três estádios de ensacamento, ou seja, quando os diâmetros médios deles atingiram 0,5cm, 1,0cm e 1,5cm. Após os frutos atingirem o tamanho de acordo com cada tratamento, realizou-se o ensacamento das panículas, utilizando papel jornal. Quando maduros, os frutos foram colhidos e avaliados quanto ao comprimento, diâmetro e massa do fruto, presença de danos internos e externos. O ensacamento em diferentes estádios de desenvolvimento interferiu na qualidade dos frutos de nespereira. Frutos ensacados com diâmetros entre 0,5 e 1,0cm foram os que apresentaram a melhor qualidade comercial. A seleção IAC NE-3 se destacou entre as nespereiras quanto às dimensões dos frutos.

The bagging is an operation of extreme importance in the loquat culture because it provides fruit quality, and allows minimization of chemical products use. However, there is still lack of information, related to the adequate moment to carry through the operation, especially considering the limit of bagging stage, in which there are fruits of marketable quality. Therefore, this study aimed to evaluate the quality of bagged fruits of loquat cultivars in different stadiums of development. The cultivars 'Mizuho', 'Mizumo', 'Mizauto', 'Centennial', 'Crystal Nectar' and selection IAC NE-3 were evaluated in three stages of bagging, that is, when fruits reached an average diameter of 0.5cm, 1.0cm and 1.5cm. After fruits reached the size in accordance to each treatment, the panicles were bagged using newsprint. When mature, the fruits were harvested and evaluated regardless to length, diameter and fruit mass, presence of internal and external damages. The bagging at different developmental stages interfered in the quality of loquat fruit. bagged with diameters between 0.5 and 1.0cm were the ones that had presented the best commercial quality. The IAC NE-3 selection detached e among the loquat fruit due to its dimensions.

Devido à falta de informações sobre a aplicação de nitrogênio na produção de mudas de licheira na fase de viveiro, o experimento foi conduzido em viveiro no município de Urânia-SP (20°11' 25,4'' S e 50° 37' 42,9'' O). O delineamento experimental utilizado foi de blocos ao acaso, com cinco tratamentos, que consistiram em doses de nitrogênio aplicadas na forma de uréia (45% de N) (0, 800, 1.600, 2.400, 3.200 mg dm-³ de substrato) com quatro repetições e dez plantas por parcela. Após 104 dias do início do experimento, foi avaliado o comprimento da parte aérea e do sistema radicular, número de folhas e o teor de clorofila. Houve efeito significativo das doses de N apenas para comprimento da parte aérea e teor de clorofila. Na adubação nitrogenada de mudas de licheira, a dose de 2.188,33 mg dm-³ de N no substrato proporcionou o maior comprimento da parte aérea das plantas. O teor de clorofila nas folhas das mudas de lichia aumentou linearmente com o aumento das doses de nitrogênio.

Because the lack of information on nitrogen application in the production of lychee seedlings in the nursery stage, the present work was carried out in a nursery in the municipality of Urânia-SP (20°11' 25.4'' S and 50° 37' 42.9'' W). The experiment was arranged in a randomized block design with five treatments (five rates of nitrogen in form of urea - 45% N): 0, 800, 1600, 2400 and 3200 mg.dm-3 of substrate, with four replications and ten plants for replication. One hundred and four days days after planting, the length of aerial part and roots, number of leaves and content of chlorophyll were evaluated. There was significant effect of N rates only for length of aerial part and chlorophyll content. Nitrogen fertilization of lychee seedlings at the concentration of 2188.33 mg.dm-³ of N in the substrate provided the greatest length of the aerial part. Chlorophyll content in the leaves increased linearly with nitrogen rates.

Visando a dar suporte a trabalhos de melhoramento genético para porta-enxertos de pera e ajuste de protocolo de germinação de pólen para fins de polinização intra e interespécies, objetivou-se ajustar os componentes básicos do meio de cultura e as condições ambientais para a realização de testes de germinação in vitro e viabilidade de grãos de pólen dos porta-enxertos para pereiras 'Taiwan Nashi-C' (Pyrus calleryana) e 'Taiwan Mamenashi' (P. betulaefolia). O pólen utilizado foi obtido de anteras provenientes de flores em estádio de balão. Em seguida, com auxílio de um pincel n°2, os grãos de pólen foram espalhados sobre a superfície de placas de Petri, contendo 20ml de meio de cultura de acordo com os seguintes experimentos: 1) concentrações de sacarose (0, 30, 60 e 90g L-1) e agar (4, 6, 8 e 10g L-1); 2) concentrações de nitrato de cálcio (0, 200, 400 e 800mg L-1) e ácido bórico (0, 400, 800 e 1200mg L-1); 3) valores de pH (4,0; 4,5; 5,0; 5,5; 6,0 e 6,5); 4) temperaturas (20; 25; 30 e 35); e 5) tempo de emissão do tubo polínico (1, 2, 3, 4, 5, 6 e 12 horas após a inoculação), os quais foram montados de forma sequencial. A utilização de 10g L-1 de agar e 90g L-1 de sacarose para o porta-enxerto 'Taiwan Mamenashi' e 47,78g L-1 para 'Taiwan Nashi-C', com 795 a 838mg L-1 de ácido bórico, na ausência de nitrato de cálcio, pH entre 5,2 e 5,8 e temperatura de 28°C, proporcionou as melhores condições de germinação de grãos de grãos. A porcentagem máxima de polens germinados é obtida com oito horas após a inoculação para 'Taiwan Nashi-C' e com 12 horas para 'Taiwan Mamenashi'.

In order to support the works with genetic improvement for pear rootstocks and adjust the pollen germination protocol for intra and inter species polinization, this study aimed to adjust the culture medium basic compounds and environmental conditions for the realization of in vitro pears pollen grains germination and viability tests of 'Taiwan Nashi-C' (Pyrus calleryana) e 'Taiwan Mamenashi' (P. betulaefolia) pear rootstock. Thus, five experiments were performed: 1) Sucrose concentrations (0, 30, 60 and 90g L-1) and agar (4, 6, 8 and 10g L-1); 2) calcium nitrate (0, 200, 400 and 800mg L-1) and boric acid (0, 400, 800 and 1200mg L-1); 3) pH (4.0; 4.5; 5.0; 5.5; 6.0 and 6.5); 4) temperatures (20; 25; 30 and 35 ) and 5) emission time of the pollen tube (1, 2, 3, 4, 5, 6 and 12 hours after inoculation), which were assembled sequentially. The use of 10g L-1 of agar combined with 90g L-1 sucrose for the rootstock 'Taiwan Mamenashi' and 47.78g L-1 for the 'Taiwan Nashi-C', with 795 to 838mg L-1 of boric acid, under absence of calcium nitrate and pH between 5.2 and 5.8 and temperature of 28 °C, provided the best conditions to the germination of the pollen grains. The maximum percentage of germinated pollen is obtained with eight hours after inoculation for 'Taiwan Nashi-C' and twelve hours for 'Taiwan Mamenashi'.