This study aimed to determine the physiological maturity of A. edulis seeds, check if this is achieved in the same maturation stage, regardless of the collection region and, colorimetry of the fruit can be indicative of the time of harvest. Fruits were harvested in three counties of the western region of Paraná and visually classified into five ripening stages according to the color of the pericarp with the help of a digital colorimeter. Analyzed seed variables included morphological characteristics, germination and vigor. The experiment was conducted in a completely randomized design with four replications. The maximum dry matter accumulation of seeds was reached when the fruits reached the color orange. With the advance of the ripening process, red color fruits had seeds with lesser moisture content, coinciding with the maximum germination percentage and speed, besides generating seedlings with larger size and biomass accumulation. The green spectrum allowed to discriminate maturity from different places of harvest. A. edulis seeds with physiological maturity should be harvested when fruits present the red color, independent of the harvesting region or, with reflectance values between 28.0 and 49.2 nm in the green range of the color spectrum.

-The study aimed to adjust the methodology of the tetrazolium test to estimate seed viability of Eugenia uniflora L. (Surinam Cherry). Seeds were collected in September 2012 and divided into four lots: freshly harvested (Lot I); stored in plastic bags in a refrigerator at 10 °C for: 15 days (Lot II); 30 days (Lot III); and 45 days (Lot IV). The freshly harvested seeds were preconditioned with direct immersion in water and wet paper towel, followed or not by longitudinal cutting. The seeds were immersed in a 0.1% tetrazolium solution for 4 hours at 30 °C. Appropriate soaking and preparation methods were applied to the seeds lots using three tetrazolium concentrations: 0.1; 0.5; and 1.0%; and four preconditioning periods (2, 4, 6 and 8 hours) at 30 °C. The viability results obtained by the tetrazolium test were compared with those of the germination test. Direct immersion of seeds in water for 24 hours at 25 °C, followed by a longitudinal cut was efficient for preconditioning the seeds. Seed staining with tetrazolium solution at a concentration of 0.5% for 2 hours at 30 °C can be used to estimate the viability of freshly harvested and stored Surinam Cherry seeds.Index terms: viability test, surinam cherry, native fruit.Adequação da metodologia do teste de tetrazólio para estimativa da viabilidade de sementes de Eugenia uniflora L. submetidas ao armazenamento RESUMO -O estudo teve como objetivo adequar a metodologia do teste de tetrazólio para estimativa da viabilidade de sementes de Eugenia uniflora (pitanga). As sementes colhidas em setembro de 2012 foram divididas em quatro lotes: recém-colhidas (lote I), armazenadas em sacos plásticos em refrigerador a 10 °C durante 15 (lote II); 30 (lote III) e 45 dias (lote IV). As sementes recém-colhidas foram submetidas aos pré-condicionamentos: embebição direta em água e em rolo de papel umedecido, ambos por 24 horas a 25 ºC e, em seguida, submetidas ou não ao corte longitudinal. Posteriormente, as sementes foram imersas em solução de tetrazólio a 0,1% por quatro horas a 30 ºC. O método de embebição e preparo mais adequados foram aplicados aos lotes, utilizando-se três concentrações de tetrazólio: 0,1; 0,5 e 1,0% e quatro tempos de coloração (2, 4, 6 e 8 horas) a 30 ºC. Os resultados obtidos pelo teste de tetrazólio foram comparados com os de germinação. A imersão direta das sementes em água por 24 horas a 25 ºC, seguida do corte longitudinal, apresentou eficiência no pré-condicionamento de sementes de pitanga. O teste de tetrazólio a 0,5% por 2 horas a 30 ºC pode ser utilizado para estimar a viabilidade tanto de sementes recém-colhidas como armazenadas.Termos para indexação: teste de viabilidade, pitanga, frutífera nativa.

-The study aimed to adapt the tetrazolium test methodology to assess the viability of seed of Eugenia involucrata DC. (cherry) and E. pyriformis Cambess. (uvaia) freshly harvested and stored. Three lots of seeds of both species were used, being I (freshly harvested), II (stored for 15 days) and III (stored for 30 days). Seeds (lot I) of both species were immersed in distilled water for 24 hours and submitted to four preparation methods: whole seeds without seed coat and with ¾ of seed coat; longitudinally cut with and without seed coat (immersed in 0.1% tetrazolium for 4 hours). The most suitable preparation method was applied to the remaining lots, where three tetrazolium concentrations were tested: 0.075, 0.1 and 0.5% and three immersion time periods: 2, 4 and 6 hours. The tetrazolium test results were compared to the germination results. For the conduction of the tetrazolium test in seeds of both species we recommend soaking in distilled water by 24 hours and cut lengthwise on seeds with the seed coat. For cherry, the seeds should be immersed in 0.5% tetrazolium solution for 2 hours. For uvaia seeds, additional studies are recommended.Index terms: viability test, cherry, uvaia, forest species.Teste de tetrazólio para a estimativa de viabilidade de sementes de Eugenia involucrata DC. e Eugenia pyriformis Cambess. RESUMO -O estudo teve como objetivo adequar a metodologia do teste de tetrazólio para avaliar a viabilidade das sementes de Eugenia involucrata DC. (cereja) e E. pyriformis Cambess. (uvaia) recém-colhidas e armazenadas. Foram empregados três lotes de sementes para ambas as espécies, sendo o I (recém-colhidas), II (armazenadas durante 15 dias) e III (armazenadas durante 30 dias).As sementes (lote I) de ambas as espécies, foram imersas em água destilada por 24 horas e submetidas a quatro métodos de preparo: sementes inteiras sem tegumento e com ¾ do tegumento; sementes cortadas longitudinalmente com tegumento e sem tegumento (imersas em solução de tetrazólio a 0,1% por 4 h). O método de preparo mais adequado foi aplicado aos demais lotes, utilizando-se três concentrações de tetrazólio: 0,075; 0,1 e 0,5% e três tempos de imersão: 2, 4 e 6 h. Os resultados do teste de tetrazólio foram comparados com os de germinação. Para a condução do teste de tetrazólio em sementes de ambas as espécies recomenda-se a embebição em água destilada por 24 horas e corte longitudinal das sementes com o tegumento. Para cereja, recomenda-se a imersão das sementes em solução de tetrazólio a 0,5% por 2 horas. Para uvaia, recomendam-se estudos adicionais.Termos para indexação: teste de viabilidade, cereja, uvaia, espécie florestal.

The study aimed to evaluate the control of Meloidogyne incognita in resistant and susceptible tomato genotypes treated with hydrogel containing avocado extracts (Persea americana Mill.). The methanolic extract of avocado seeds was evaporated and re-suspended in distilled water containing Tween 80 (0.6%). The extract was prepared with the following concentrations: 100, 200, 400, 800 and 1000 mg L ), for in vivo testing. The hydrogel containing avocado extract was added to the pits of tomato plants during transplanting, and after three days, M. incognita was inoculated. After 30 days, the relative chlorophyll content was assessed, along with the total volume of root, the number of galls and egg masses, viability of the egg mass, and number of eggs and juveniles per root system in 100 cm 3 of soil. From these assessments, the most effective dose in the control of nematodes was tested again with the extract concentrations of 1000, 2000, 4000, 6000 and 8000 mg L -1 in the hydrogel, which was added to the pits at the time of transplantation. After 30 days of inoculation the same evaluations were performed. In vitro, the concentration of 1000 mg L -1 of the avocado extract was the most effective in reducing the hatched juveniles, while motility and mortality were not influenced. In vivo, 1.0 g pit -1 dose in the first test had greater control of nematodes in susceptible plants for all variables assessed. It was incorporated into the pits of tomato plants for the realization of the second test. In this, the concentration of 8000 mg L -1 was the most effective in controlling M. incognita. Therefore, the avocado seed extract served in hydrogel has the potential to control M. incognita in tomato plants.