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ABSTRACT The use of cold plasma is effective in overcoming seed dormancy. However, its effects, both in the long-term and during storage, is still not fully understood. The aim of this study, therefore, was to evaluate the immediate and post-storage effect of atmospheric plasma on the seeds of Pityrocarpa moniliformis in overcoming seed coat dormancy. The seeds were treated with plasma for 0, 1.0, 2.0, 3.0, 4.0 and 5.0 minutes. Following application, 50% of the seeds were stored for two years while the remainder were submitted to immediate analysis. The seeds were evaluated for germination and the germination speed index, in addition to seedling length and dry weight. The experimental design was completely randomised, and included regression analysis. The plasma treatment resulted in an increase in the germination rate and vigour of the seeds, both immediately after exposure and after two years of storage. In particular, the seeds treated for five minutes showed around 39% germination, which was outstanding compared to seeds from other exposure times. Plasma is effective in overcoming seed coat dormancy in seeds of P. moniliformis treated for five minutes and tested immediately. The effect of plasma on the seeds of P. moniliformis after storage was less for all the conditions under test.

ABSTRACT Cobalt (Co) and molybdenum (Mo) are essential elements with a fundamental role in biological nitrogen fixation in legumes. Vitamins such as thiamine, despite being required in small quantities, influence plant growth. This study aimed to assess the efficiency of different doses of thiamine applied as seed treatment, combined or not with Co and Mo, in enhancing the development of soybean crops. The experiment was conducted in a greenhouse according to a randomized block design with a 6 × 2 factorial arrangement, comprising six thiamine doses (0, 10, 25, 50, 100, and 200 mg kg-1) in the presence or absence of Co and Mo at the recommended rate of 100 mL ha-1. At 40 days after sowing, plants were analyzed for root length, root dry weight, shoot length, shoot dry weight, nodule number, and nodule dry weight. Principal component analysis showed that combined application of Co and Mo with thiamine was negatively associated with all variables and that the thiamine doses most positively associated with the analyzed variables were 50 and 200 mg kg-1. In treatments containing thiamine alone, there was a linear direct relationship between thiamine dose and nodule dry weight. Root and shoot lengths and dry weights were highest in plants treated with thiamine only at a dose of 122 mg kg-1. Application of Co and Mo combined with thiamine via seed treatment does not promote the development of soybean crops. Thiamine application is a promising treatment to increase shoot length, root dry weight, and nodule dry weight in soybean.

ABSTRACT This study investigated the effectiveness of using the X-ray technique to assess the viability of papaya seeds. The X-ray images were performed in eight replicates of 25 seeds, placed on transparent acrylic plates on double-sided adhesive tape, previously identified, and then submitted to radiation in X-ray equipment "HP Faxitron". After exposure to X-ray radiation, the seeds were submitted to the germination test in rolls of germitest paper and kept in a germination chamber at 20-30 °C for 30 days. Seedlings were photographed and evaluated as normal seedlings, abnormal and non-germinated seeds. Afterward, the X-ray images and the seedlings from the same seeds were visually compared, and the X-ray images clearly showed seeds with and without internal filling. All abnormal seedlings were full seeds; therefore, X-ray images were not able to separate normal and abnormal. A 100% accuracy was verified by comparing the X-ray images and their respective seedlings, full seeds originated normal or abnormal seedlings, and empty seeds corresponded to non-germinated seeds. Therefore, using X-ray images is a promising technique to identify the viability of papaya seeds. The automated analysis of X-ray images is a simple, fast, and efficient technique to provide information on seed viability and generate parameters related to their germination capacity.

ABSTRACT The objective was to verify if the primary root emission can be recommended as a vigor test for soybean seeds. For this, five lots of varieties ANTA 82, NA7337 and BRS1074IPRO were evaluated by first count, germination, emergence, emergence speed index and tetrazolium tests. In the root protrusion test at 20, 25 and 30 ºC, two evaluation criteria were adopted: primary root emission precocity index (PREPI) and percentage of seeds that emitted the primary root (PRE). The seeds counted were those with a primary root equal to or greater than 2 mm, every 12 h from the installation of the test until 120 h. The design was completely randomized and means were compared, within each evaluation time, using the Scott-Knott test at 5% probability. Pearson’s linear correlation was performed for PREPI and PRE with emergence. PREPI was not considered efficient. For the PRE, at 20 ºC, there was a correlation at 72 h, for the three varieties. At 25 ºC there was a correlation for a period of 36 h for ANTA 82 and NA7337 and 60 h for BRS1074IPRO. At 30 ºC there was a correlation in the time of 36 h for the three cultivars. Considering that speed in obtaining results is important in vigor tests, it is concluded that primary root emission for 36 h after installing the test at 30 ºC is recommended as a vigor test in the quality control of soybean seeds.

A qualidade de sementes de mamona tem sido avaliada rotineiramente pelo teste de germinação, cujos resultados, muitas vezes, não são confirmados em campo. Nesse contexto, os testes de vigor são essenciais, pois retratam o comportamento das sementes sob maior amplitude de ambiente. Neste trabalho, objetivou-se avaliar a eficiência de métodos para determinar o potencial fisiológico de sementes de mamona. Para tanto, foram utilizados sete lotes de sementes de mamona, cultivar AL-Guarany, apresentando teor de água de aproximadamente 7% , que foram submetidos aos seguintes testes: germinação, primeira contagem de germinação, frio (a 10ºC/7 dias e a 25ºC/5 dias), porcentagem e velocidade de emergência de plântulas, envelhecimento acelerado a 41ºC e 45ºC e 100% UR, por 48, 72 e 96 horas e condutividade elétrica (25 sementes embebidas em 75 e 100mL de água destilada, a 25ºC, por 2, 4, 6, 8, 24, 48 e 72 horas). Os testes de frio e de envelhecimento acelerado (41ºC/72 horas e 100% UR) foram eficientes para avaliação do potencial fisiológico de sementes de mamona, permitindo classificação de lotes quanto ao vigor semelhante à emergência de plântulas em solo. O teste de condutividade elétrica não se mostrou adequado para avaliação do potencial fisiológico das sementes de mamona.This work had the objective to determine the efficiency of different tests for the evaluation of physiological potential of castor bean seeds. Seven seed lots of AL-Guarany cultivar were submitted to the following tests: seed moisture content, standard germination, first count, cold test (10ºC/7 days followed by germination at 25ºC/5 days), seedling emergence, speed emergence index, accelerated aging (at 41ºC and 45ºC and 100% RH, for 48, 72, and 96h) and electrical conductivity (25 seeds soaked into 75 and 100mL of distilled water, at 25ºC, for 2, 4, 6, 8, 24, 48, and 72 h). The trial was conducted in randomized completely design, with four replications. The means of treatments were compared by Tukey test at 5% probability. Results showed that cold test and accelerated aging (41ºC/72 hours) were efficient to evaluate the physiological potential of castor bean seeds, allowing the classification of lots regarding vigor to be similar to the seedling emergence test. Electrical conductivity test was not adequate for the evaluation of physiological potential of these seeds.

Glyphosate effects on leaf micronutrients contents of transgenic soybean have been widely reported, however, little is known about these effects associated with other pesticides. The objective of this study was to evaluate the physiologic quality and yield of soybean seeds, as well as leaf micronutrients contents, according to weed control methods. Ten RBD treatments were arranged in a split-plot scheme with four replications. The application or non-application of endosulphan + tebuconazole was evaluated in the plots, while the weeds control methods were assessed in the subplots (weeded control; non-weeded control; single application of glyphosate (1,080 g ha-1) and fomesafen + fluazifop-?-butil (180 + 225 g ha-1), both at 15 DAE; and sequential application of glyphosate (1,080 g ha-1) at 15, 30, and 45 DAE). After harvesting, the soybean seeds were sampled, in order to evaluate their germination, vigor, and yield. Copper and manganese contents were only influenced by the sequential application of glyphosate, associated with endosulphan + tebuconazole. The cold test germination was reduced in seeds of plants treated with fomesafen + fluazifop-p-butil associated with endosulphan + tebuconazole. Among the treatments without endosulphan + tebuconazole, the sequential application of glyphosate promoted the highest 100-seeds weight, as well as, when associated with endosulphan + tebuconazole, reduced the leaf concentrations of Cu and Mn, however, it improved seeds germination and showed no effects on seeds vigor, when compared with the weeded soybean.Efeitos do glyphosate nos teores foliares de micro-nutrientes de soja transgênica têm sido amplamente relatados, porém, pouco se sabe sobre seus efeitos associados a outros agrotóxicos. Objetivou-se, neste trabalho, avaliar a produção e a qualidade fisiológica de sementes de soja, bem como os teores de micronutrientes nas folhas, em função de métodos de controle de plantas daninhas. Foram avaliados dez tratamentos DBC, em esquema de parcelas subdivididas, com quatro repetições. Nas parcelas, avaliou-se o efeito da aplicação ou não de endossulfan + tebuconazole e, nas subparcelas, o efeito dos métodos de controle de plantas daninhas (testemunha não capinada; testemunha capinada; aplicação única de glyphosate (1.080 g ha-1) e fomesafen + fluazifop-?-butil (180 + 225 g ha-1), ambas aos 15 DAE; e aplicação sequencial de glyphosate (1.080 g ha-1), aos 15, 30 e 45 DAE). Após a colheita da soja, as sementes foram amostradas, para avaliar a sua germinação, vigor e produtividade. Os teores de manganês foram influenciados pela aplicação sequencial de glyphosate, associada ao endossulfan + tebuconazole. A germinação do teste de frio foi reduzida em sementes de plantas tratadas com fomesafen + fluazifop-p-butil, em associação com endossulfan + tebuconazole. Dentre os tratamentos sem endossulfan + tebuconazole, a aplicação sequencial de glyphosate promoveu a maior massa de cem sementes, bem como, associada à mistura endossulfan + tebuconazole, diminuiu os teores foliares de Cu e Mn, porém, melhorou a germinação e não influenciou no vigor das sementes, em relação à soja capinada.

ABSTRACT Among the main problems that compromise the development of forest species are water and salt stresses, especially in the early stages of development, when seedlings are more sensitive. Thus, the objective of this study was to evaluate the morphophysiological and biochemical changes in Enterolobium contortisiliquum seedlings subjected to abiotic stresses. The experimental design was randomized complete blocks (RCB), composed of five treatments, with four replicates, and the experimental plot consisted of twenty plants. From the 31st day after sowing, when the seedlings reached approximately 15 cm in height, they began to receive the treatments, which consisted of different levels of electrical conductivity of irrigation water (0.3; 2; 4; 6; 8 dS m-1) for salt stress and periods of water restriction (0; 4; 8; 12 and 16 days without irrigation) for water stress. The traits evaluated were: plant height, root length, stem diameter, number of leaves, leaf area, total dry matter, Dickson quality index, height/shoot dry matter ratio, total soluble sugars, starch, total amino acids and proline. An increase in the electrical conductivity of irrigation water and days without irrigation compromised the development of E. contortisiliquum seedlings, which was intensified from 2 dS m-1 and four days without irrigation for salt and water stresses, respectively. The mechanism of survival of E. contortisiliquum to abiotic stresses involves reduction in the growth and quality of seedlings, with activation of biochemical defense mechanisms of the species.

ABSTRACT Establishing the appropriate procedures for conducting germination tests in forest species is important for marketing the seeds, especially species that are not yet included in the relevant Normative Instructions. The aim of this study was to determine the ideal conditions of temperature and substrate to carry out the germination test on seeds of Senna siamea, as well as: (i) to characterise the morpho-physiology of seedling establishment, (ii) the period for seedling evaluation, and (iii) validate the efficiency of the methodology in 10 batches of seeds. The experimental design was completely randomised in a 2 x 2 factorial scheme (temperatures x substrates), with 12 replications of 50 seeds in each treatment. To evaluate the different batches, the data were submitted to analysis of variance, and the mean values compared by the Scott-Knott test at 5% probability. The percentage and speed of germination, first count, seedling length, accumulated germination, and seedling morphology were evaluated. The germination potential of S. siamea seeds is greater on paper-roll substrate at temperatures of 25 °C and 30 °C (86% and 87%). The first germination count and final seedling evaluation should be carried out 15 and 21 days after sowing, respectively. The species has epigeal germination and the seedlings are phanerocotyledonous. It was found that the method for carrying out and evaluating the germination test recommended in this study is suitable for evaluating batches of S. siamea seeds.

ABSTRACT New and refined technologies based on computerized procedures create the potential for automating laboratory evaluations, constituting an alternative to reduce costs and increase the decision-making capacity regarding the destination of seed lots. The objective of this study was to evaluate the efficiency of the Sistema de Análise de Plântulas (SAPL ®) free digital image processing software of seedlings in characterizing the physiological potential of maize seeds in comparison with information provided by vigor tests recommended for this species. Ten lots of maize seeds were submitted to germination, first germination count, germination speed index, seedling emergence, cold test and electrical conductivity. The results of these tests were compared with the data obtained from the image analysis, which evaluated the development of seedlings at three and five days counted from the beginning of the germination test, by obtaining values of seedling length, growth, development uniformity, vigor index and corrected strength index. SAPL ® is a consistent and promising alternative for evaluating the physiological potential of maize seeds, presenting a high correlation of its variables with the traditional tests used. The evaluation can be performed on the third and fifth day after the germination test is installed.

The germination of papaya seeds is slow and uneven, usually due to inhibitors present in the sarcotesta; however, some removal procedures may cause physical damage, negatively interfering in the physiological quality and field performance. This study aimed to evaluate the physical and physiological quality of papaya seeds submitted to methods of sarcotesta removal by image analysis. Papaya Formosa ‘Tainung 01' seeds were submitted to the following methods of sarcotesta removal: fermentation + sieve, sand + sieve, sieve and blender + sieve. After the sarcotesta removal, the seeds were submitted to tests of germination, first germination count, germination speed and seedling length. For the image analysis, the seeds without sarcotesta were submitted to the X-ray test and to a computerized analysis of seedling images by the SVIS® software. The methods used were only promising for the sarcotesta removal, while the blender + sieve method obtained the highest physical and physiological seed quality, in addition to performing the best sarcotesta removal. However, the image analysis using the SVIS® software allowed to identify the high physical and physiological seed quality using the blender + sieve method, which promoted the highest efficiency in removing the sarcotesta.

Obtaining image-based information is a powerful approach to capture and quantify seed vigor data. However, commercial systems that facilitate the processing and acquisition of images are often cost prohibitive. This study aimed to evaluate the efficiency of the Seedling Analysis System (Sistema de Análise de Plântulas - SAPL®), in order to analyze the physiological potential of soybean seeds, in comparison with the information provided by vigor tests which are traditionally recommended for this species. Nine lots of soybean seeds were submitted to germination, germination speed, seedling emergence, cold test and electrical conductivity tests. In the SAPL® analyzes, seedlings of four and six days, counted from the beginning of the germination test, were evaluated, resulting in values ​​for seedling length, growth, development uniformity, vigor index and corrected vigor index. The evaluated lots with emergence greater than 90 % showed a vigor index higher than 600 and 800, respectively in the fourth and sixth days. The indexes generated by SAPL®, except for the uniformity index, presented positive and high correlations with the traditional tests (> 0.80). SAPL® is efficient in identifying differences in the vigor of soybean seed lots.

Fertilization and harvest time may influence the formation and maturation processes, as well as the physiological quality of seeds. This study aimed at evaluating the effect of fertilization on the physiological maturation of sesame seeds. The following variables were evaluated: fruit color, dry mass and water content of fruits and seeds, germination, first germination count, germination speed, emergence and emergence speed. No significant fertilization effect was observed on fruit maturation for water content or dry mass. However, there was significance for these variables in the seeds. The harvest time had a significant effect on water content and dry mass of fruits and seeds. For the variables that evaluated the seed viability and vigor, both the fertilization and harvest time influenced the physiological maturation. The physiological maturity of the sesame seeds, whose plants were grown with and without fertilization, was reached between 52 and 54 days after anthesis, when the fruits were classified as yellow-greenish 7.5 Y 8/6 and yellow to yellow-red 10.R 4/6.

Jatropha curcas L. is an oleaginous plant that has distinguished itself by presenting the qualities necessary to the biodiesel production. This study aimed to adjust the accelerated aging test methodology to evaluate the physiological potential of Jatropha curcas seeds. For this, four seeds lots were initially characterized by water content, germination percentage and first counting, seedlings emergence percentage and speed index, low temperature germination, and shoot height. The treatments included three temperatures (41ºC, 42ºC, and 45ºC) and four seeds exposure times (24, 48, 72, and 96 hours), in about 100% relative humidity. The accelerated aging test carried out for 24 hours, at 41ºC, was efficient for evaluating the Jatropha curcas vigour seeds, allowing to classify lots according to vigour levels, similarly to the germination first counting tests, seedlings emergence, low temperature germination, emergence speed index, and shoots height.

The first step sequence that involves the germination process is imbibition. The limitation of water to the seed at planting time can reduce germination and velocty as well as the development of the seedling. Hence, the objective of this study was to evaluate the germination and seedling development of jatropha under conditions of water stress by polyethylene glycol (PEG6000). The study was conducted at the Research Laboratory of the Department of Crop Seeds, Federal University of Viçosa. We used seeds of jatropha in temperature de 30 °C under osmotic potential levels of 0.0, -0.2, -0.4, -0.6, -0.8, -1.0 and -1.2. The performance of seed germination and seedling development were evaluated by germination (first and second count), index of germination velocity, time of germination, length and primary root and hypocotyl length. The experimental design was completely randomized design with six levels of osmotic potential to more witnesses and four replications. We conducted the analysis of variance and regression of the data and curves fitted by quadratic polynomial model for all variables. The reduction in osmotic potential of the substrate caused a significant reduction in germination of seeds of jatropha, as well as the speed of germination and seedling performance of this species. The fall of germination and seedling performance is enhanced and levels considered critical to -0.2 MPa and inhibits germination from -1.2 MPa.A primeira etapa da seqüência que envolve o processo germinativo é a embebição. A limitação de água para a semente no momento da semeadura pode diminuir a germinação e sua velocidade, bem como o desenvolvimento da plântula. Diante disto, o objetivo deste trabalho foi avaliar o desempenho germinativo e o desenvolvimento de plântulas de pinhão manso sob condições de estresse hídrico simulado por polietilenoglicol (PEG6000). O trabalho foi desenvolvido no Laboratório de Pesquisa em Sementes do Departamento de Fitotecnia da Universidade Federal de Viçosa. Utilizaram-se sementes de pinhão manso em temperatura de 30ºC sob os níveis de potencial osmótico de 0,0; -0,2; -0,4; -0,6; -0,8; -1,0 e -1,2. O desempenho germinativo das sementes e o desenvolvimento das plântulas foram avaliados pelos testes de germinação (primeira e segunda contagem), Índice de velocidade de germinação, tempo médio de germinação, comprimento de raiz primária e comprimento do hipocótilo. O delineamento estatístico utilizado foi o inteiramente casualizado com seis níveis de potencial osmótico mais a testemunha com quatro repetições. A redução do potencial osmótico do substrato reduziu expressivamente a germinação das sementes de pinhão manso, bem como a velocidade de germinação e o desempenho das plântulas. Maior redução da germinação e do desenvolvimento inicial das plântulas foi observado no potencial osmótico de -0,2MPa. A aprtir de-1,2MPa houve inibição da germinação.

Adenanthera pavonina L. is a native tree specie from India and with extensive distribution in all Brazilian states, whose seeds have dormancy and present medicinal and economical interest. The objective of this research was to evaluate the effect of different temperatures and pre-germinative treatments on the germinative behavior of newly collected A. pavonina seeds. The seeds were submitted to three settled temperatures: 20, 25 and 30ºC; and to five pre-germinative treatments: coating cutting with pliers, friction in sandpaper, immersion for twenty minutes in sulfuric acid, immersion in water at 80ºC for 5 minutes and control (without any treatment). The vigor of the seeds was evaluated by the percentage, first count, speed and mean time of germination. The experimental design used was a completely randomized with four replications and the averages were compared by the Tukey test, at 5% probability. The best germinative performance of the seeds was at temperatures of 20 and 25°C and in the pre-germinative treatments of mechanical scarification through the coating cutting with pliers and friction in sandpaper, and chemical scarification with immersion for 20 minutes in sulfuric acid.Adenanthera pavonina L. é uma espécie arbórea nativa da Índia e de ampla distribuição em todos os estados brasileiros, cujas sementes possuem dormência e apresentam interesse medicinal e econômico. O objetivo desta pesquisa foi avaliar o efeito de diferentes temperaturas e tratamentos pré-germinativos sobre o comportamento germinativo das sementes de A. pavonina, recém colhidas. As sementes foram submetidas a três temperaturas fixas: 20, 25 e 30ºC; e a cinco tratamentos pré-germinativos: desponte com alicate, atrito em lixa, imersão em ácido sulfúrico por vinte minutos, imersão em água a 80ºC por 5 minutos e testemunha (sem tratamento). O vigor das sementes foi avaliado pela porcentagem, primeira contagem, velocidade e tempo médio de germinação. Utilizou-se o delineamento inteiramente casualizado, com quatro repetições e as médias foram comparadas pelo teste de Tukey, a 5% de probabilidade. O melhor desempenho germinativo das sementes foi nas temperaturas de 20 e 25°C e nos tratamentos pré-germinativos de escarificação mecânica através do desponte com alicate e atrito em lixa, e escarificação química com imersão em ácido sulfúrico por 20 minutos.

Uniformity and percentage of seedling emergence of direct-seeded vegetables have a major impact on their yield and quality. Depending on temperature and soil water potential, carrot seeds performance in the field is poor justifying the use of techniques to accelerate the germination and seedling emergence. The objective of this work was to evaluate the effects of priming treatments, with and without aeration, on carrot seeds performance under water and temperature stress. Two seed lots of carrots, Brasília cultivar, were primed in PEG 6000 -1.0 and -1.2 MPa solutions, for four and eight days, at 20ºC, using two imbibition methods: priming in paper towel moistened with the respective solutions and immersion into aerated osmotic solutions. Non-primed seeds were used as control. After priming, the seeds were dried at room temperature until reach initial seed moisture content. The seeds were submitted to the following tests: germination, first count, seedling emergence in the field, germination at sub-optimal (15ºC) and supra-optimal temperature (30ºC) and germination under water stress (PEG 6000 at -0.4 MPa). Priming in -1.0 and -1.2 MPa PEG 6000 during four and eight days can be useful for improving carrot seedling emergence in the field and seed performance under supra and sub-optimal temperatures. Aeration of the peg solution was beneficial when seeds were primed at -1.2 MPa for eight days.Na cultura da cenoura são constantes os problemas relativos ao desempenho das sementes em campo, justificando técnicas que acelerem a germinação das sementes e a emergência das plântulas. O objetivo deste trabalho foi avaliar o efeito do condicionamento osmótico, com e sem uso de soluções aeradas, no desempenho de sementes de cenoura sob estresse hídrico e térmico. Para tanto, sementes de dois lotes, cv. Brasília, foram condicionadas em soluções de PEG 6000 a -1,0 e -1,2 MPa, por quatro e oito dias, a 20ºC, utilizando-se dois métodos de embebição para o condicionamento: em papel toalha umedecido com as respectivas soluções e imersão em soluções osmóticas aeradas. Sementes não condicionadas foram utilizadas como testemunha. Após o condicionamento, as sementes foram secas em ambiente de laboratório até atingirem o grau de umidade inicial. Em seguida, foram avaliadas pelos seguintes testes: germinação, primeira contagem de germinação, emergência das plântulas em campo, germinação a temperatura sub (15ºC) e supra-ótima (30ºC) e germinação sob estresse hídrico (PEG 6000 a -0,4 MPa). O condicionamento osmótico das sementes de cenoura em soluções de PEG 6000 a -1,0 e -1,2 MPa, por quatro e oito dias, é recomendado para aumentar a emergência de plântulas em campo e o desempenho sob temperatura sub e supra-ótima. O uso de soluções aeradas de PEG foi benéfico apenas quando as sementes foram condicionadas a -1,2 MPa por oito dias.

O presente trabalho objetivou estudar a maturação fisiológica de sementes de quaresmeira (Tibouchina granulosa Cogn.). Cada inflorescência foi identificada em sua respectiva data de antese. Os frutos foram colhidos semanalmente para avaliações de diâmetro, peso, coloração, grau de umidade e massa de matéria seca. As sementes foram avaliadas quanto à massa de 1.000 sementes, velocidade e porcentagem de germinação. As determinações foram conduzidas com quatro subamostras de 50 frutos e sementes, por colheita, em delineamento inteiramente casualizado. A maturação fisiológica das sementes ocorreu entre 84 e 105 dias, a colheita deve ser feita entre 84 e 98 dias, e a deiscência dos frutos ocorre 105 dias após a antese. O teor de água e a massa de matéria seca foram os índices que melhor caracterizaram a maturação fisiológica e época de colheita das sementes; o tamanho dos frutos e a coloração das sementes revelaram-se como bons indicadores do ponto de maturação fisiológica. A maior porcentagem de germinação foi obtida entre 77 e 110 dias, e o vigor das sementes aumenta até 91 dias após a antese. As sementes de Tibouchina granulosa apresentaram dormência após a maturação fisiológica.The objective of this work was to study the maturation process of Tibouchina granulosa Cogn. seeds. Each inflorescence was identified in the day of its respective anthesis. Samples of fruits and seeds were collected weekly, and diameter, weight, color, moisture content and dry matter were determined. After seed extraction, analyzes were made for coloring, moisture content, dry matter, 1,000 seeds mass, speed and percentage of germination. Experimental design was carried out in a completely randomized block with four replications. Analysis of data obtained led to the following conclusions: seeds physiological maturity occurred 84 to 105 days, and seed harvest should be done between 84 to 98 days after the anthesis. The parameters which best characterized seed physiological maturity and the time for harvesting were moisture content and dry matter weight. The largest germination percentage was verified in extracted seeds from 77 until 105 days after the anthesis, and seeds vigor increased until 91 days. The size and color of fruits and seeds demonstrated efficiency as maturation parameters. Fruits initial dehiscences occurred after 105 days of the anthesis. Tibouchina granulosa presented seed dormancy after maturation.

Cubiu is a native plant of the Amazon that has attracted attention due to its nutritional and pharmaceutical properties. The objective of this study was to adequate the methodology of accelerated aging test for vigor evaluation of solanum sessiliflorum seeds. Four seed lots of solanum sessiliflorum were tested for germination, first counting, plantule length, emergence and germination speed index. For accelerated aging, the temperatures 41ºC, 42ºC, and 45ºC were tested for 24, 48, 72, and 96 hours. The accelerated aging test was efficient for vigor evaluation of solanum sessiliflorum seeds, with results similar to those found for first germination counting, plantule length, emergence and germination speed index, especially when conducted at 41ºC, for 72 or 96 hours. KEY-WORDS: Solanum sessiliflorum Dunal; physiological quality; vigor; deterioration. O cubiu é uma planta nativa da Amazônia, que tem despertado interesse pelas suas características nutricionais e farmacêuticas. O presente trabalho teve por objetivo adequar a metodologia do teste de envelhecimento acelerado, para a avaliação do vigor de sementes de cubiu. Para isto, sementes de quatro lotes foram submetidas a testes de germinação, primeira contagem, comprimento de plântula, emergência e índice de velocidade de germinação (IVG). Para o teste de envelhecimento acelerado, foram testadas as temperaturas de 41ºC, 42ºC e 45ºC, durante os períodos de 24, 48, 72 e 96 horas. O teste de envelhecimento acelerado foi eficiente para avaliação do vigor das sementes de cubiu, fornecendo informações semelhantes às obtidas na primeira contagem de germinação, comprimento de plântula, emergência e IVG, principalmente quando conduzido a 41ºC, por 72 ou 96 horas. PALAVRAS-CHAVE: Solanum sessiliflorum Dunal; qualidade fisiológica; vigor; deterioração.