Resumo: A ocorrência de danos e espaço vazio no interior da semente podem afetar diretamente a germinação. O objetivo deste trabalho foi avaliar a relação entre a ocorrência de danos ou de espaço vazio no interior de sementes de feijão-caupi e o potencial fisiológico. Neste estudo foram utilizados sete lotes de sementes do cultivar BRS Guariba, que foram submetidas ao teste de raios X para identificação danos por deterioração de tecidos, danos mecânicos, danos por insetos e sementes malformadas e, posteriormente, ao teste de germinação. Na determinação dos percentuais de espaço vazio entre a área embrionária e o tegumento das sementes, foi utilizado o software ImageJ a partir de imagens radiográficas. Com base nos resultados obtidos, foi realizada a classificação das sementes em diferentes categorias, sendo os resultados confrontados com os dados de germinação. Concluiu-se que a análise de imagens radiográficas permitiu a identificação de danos e a mensuração espaço vazio na cavidade interna das sementes, possibilitando estabelecer relação entre a morfologia interna e a germinação. A presença de danos, sobretudo aqueles ocasionados por deterioração de tecidos ou danos mecânicos, a depender de sua localização e intensidade, tem potencial de afetar negativamente a germinação de sementes de feijão-caupi. Assim como, sementes que contém maiores níveis de espaço vazio em sua cavidade interna tendem a não germinar ou a gerar plântulas anormais por ocasião da germinação.

Abstract: The occurrence of damage and empty space inside the seed can directly affect germination. The aim of this study was to evaluate the relationship between the occurrence of damage or empty space inside cowpea seeds and the physiological potential. In this study, seven lots of seeds of the cultivar ‘BRS Guariba’ were subjected to the X-ray test to identify damage by tissue deterioration, mechanical damage, damage by insects and malformed seeds and, later, to the germination test. The percentage of empty space between the embryonic area and the seed coat was determined from radiographic images in ImageJ software. Based on the results obtained, the seeds were classified into different categories, and the results were compared with the germination data. It was concluded that the analysis of radiographic images allowed the identification of damage and measurement of empty space in the internal cavity of the seeds, making it possible to establish a relationship between internal morphology and germination. The presence of damage, especially that caused by tissue deterioration or mechanical damage, depending on its location and intensity, has the potential to negatively affect the germination of cowpea seeds. Likewise, seeds that contain higher levels of empty space in their internal cavity tend not to germinate or to generate abnormal seedlings at the time of germination.

Resumo: As técnicas de análise de imagens apresentam-se em expansão na agricultura e por consistirem em avaliações rápidas, simples e não destrutivas, são alternativas interessantes para a detecção de sementes de arroz imaturas. Assim, o objetivo deste trabalho foi avaliar a qualidade de sementes de arroz utilizando as técnicas de análise de imagens de raios X, multiespectrais e de fluorescência de clorofila. Inicialmente, com as sementes identificadas e enumeradas, foram obtidas imagens radiográficas para a obtenção do espaço vazio (área entre o endosperma + embrião e as glumelas). Posteriormente, com as mesmas sementes utilizadas na análise de raios X, procedeu-se a aquisição das imagens multiespectrais e de fluorescência de clorofila. Na sequência, realizou-se a análise computadorizada de plântulas com o software SVIS ®. Concluiu-se que as sementes de arroz que não germinam ou originam plântulas anormais apresentam espaço vazio interno igual ou superior a 18,68%, maior reflectância nas bandas espectrais de comprimento de onda de 590 nm a 780 nm (41,46% a 64,21%, respectivamente) e na banda de 970 nm (75,65%), além de apresentarem valores de fluorescência de clorofila iguais ou superiores a 40,58 e a 112,92, respectivamente nas energias de excitação/emissão de 630/700 nm e de 645/700 nm.

Abstract: Image analysis techniques are expanding in agriculture and, for being fast, simple, and not destroying samples, they are interesting alternatives in the detection of immature rice seeds. Therefore, the aim of this study was to evaluate the quality of rice seeds using X-ray, multispectral and chlorophyll fluorescence image analysis techniques. Initially, with the seeds identified and numbered, radiographic images were obtained to determine the free space (area between the endosperm + embryo and the glumes). Subsequently, with the same seeds used in the X-ray, multispectral and chlorophyll fluorescence images were acquired, and then the computerized seedling analysis was performed with the SVIS® software. It was concluded that rice seeds that do not germinate or originate abnormal seedlings have free space equal to or greater than 18.68%, higher reflectance in the spectral bands with wavelength from 590 nm to 780 nm (41.46% to 64.21%, respectively) and in the band of 970 nm (75.65%), in addition to having chlorophyll fluorescence values equal to or greater than 40.58 and 112.92 at excitation/emission energies of 630/700 nm and 645/700 nm, respectively.

ABSTRACT Zinc (Zn) is a micronutrient considered essential to plants which can be supplied through seed treatment. The treatment of soybean [Glycine max (L.) Merr.] seeds with Zn, however, is still not well known as regards the uptake and mobilization dynamics of the nutrient during the germination process. This study aimed to evaluate the uptake and distribution dynamics of Zn applied to soybean seeds at two levels of vigor during germination using X-ray micro-fluorescence spectroscopy (µ-XRF). Zinc treatments corresponded to 0, 2, 4 and 8 g of Zn per kg of seeds. High and low vigor seeds that had been treated were located appropriately so as to promote germination. Zn intensity measurements with µ-XRF were taken in different parts (“regions”) of the seeds (seed coat, cotyledon, and embryonic axis) after 8, 16 and 24 h of imbibition and seedlings (primary root, hypocotyl, plumule, cotyledon, and seed coat) after 48, 72 and 96 h of germination. High vigor seeds showed higher Zn intensity in the embryonic axis in the first 16 h, while low vigor seeds showed higher intensity after 24 h. After 48, 72 and 96 h of germination low vigor seedlings showed higher Zn intensity than high vigor seedlings in the primary root. It was concluded that µ-XRF is an efficient technique for identifying variances in the dynamics of Zn uptake and mobilization during the germination of soybean seeds with different vigor levels.

Resumo: As sementes de manjericão (Ocimum basilicum L.) são desuniformes, decorrente do processo de florescimento e polinização característico da espécie. Diante desse cenário, surge a necessidade de se realizar pesquisas voltadas para o estabelecimento de métodos eficazes para a identificação de sementes aptas a germinar e com potencial para originar plântulas vigorosas. O presente trabalho foi realizado com o objetivo de avaliar a relação entre a morfologia interna, por meio da análise de imagens radiográficas, e o desempenho germinativo de sementes de manjericão. Foram avaliadas radiografias de sementes de oito lotes do cultivar Alfavaca Basilicão. O comprimento das plântulas provenientes das sementes radiografadas foi obtido pela análise computadorizada de imagens, utilizando-se o software SVIS®, sendo os resultados comparados com as imagens radiográficas. Por meio das radiografias foi possível visualizar a morfologia interna das sementes de manjericão, bem como detectar sementes vazias, malformadas, com tecidos deteriorados e danos mecânicos. A análise de imagens radiográficas permitiu estabelecer uma relação de causa e efeito entre a integridade física dos tecidos com o desempenho germinativo das sementes, com potencial para a seleção de sementes que irão compor lotes de melhor qualidade.

Abstract: Sweet basil (Ocimum basilicum L.) seeds exhibit heterogeneity due to the characteristic flowering and pollination process of this species. Consequently, the necessity for research geared toward establishing effective methodologies for identifying seeds capable of germinating and with potential for producing vigorous seedlings becomes apparent. This study was undertaken with the aim of assessing the relationship between internal morphology, as evaluated through radiographic image analysis, and the germination performance of sweet basil seeds. Radiographs of seeds from eight lots of the cultivar Alfavaca Basilicão were examined. The length of seedling originated from radiographed seeds was obtained through computerized image analysis using SVIS® software and the results were compared with the radiographic images. Radiographs allowed visualization of the internal morphology of sweet basil seeds, enabling the identification of empty seeds, malformed seeds, seeds with tissue deterioration and mechanical damage. The analysis of radiographic images substantially contributed to establishing a cause-and-effect relationship between the physical integrity of tissues and the germination performance of the seeds, underscoring the potential for selecting seeds that will contribute to enhanced lot quality.

ABSTRACT. In various parts of the world, agricultural exploitation faces saline soil or water, such that cultivable species tend to be limited regarding the establishment of seedlings, with effects on productivity. The objective of this study was to evaluate the effects of salinity levels associated with different temperatures on the germination, initial development, and oxidative damage indicators of purple corn seedlings. The experiment was completely randomized in a 5 × 2 factorial design (moistening of the germination paper with 0, 25, 50, 75, and 100 mM NaCl solutions at temperatures of 25 and 30°C). The parameters evaluated were germination, growth, and oxidative damage indicators at the seedling phase. The germinative decline and initial development of purple corn seedlings, regardless of the temperature (25 and 30°C), reflected oxidative damage resulting from saline stress. Although deleterious effects of salinity were observed, a temperature of 30°C provided greater length and accumulation of dry mass of purple corn seedlings compared to the effects at 25°C. Total chlorophyll, chlorophyll a, chlorophyll b, total carotenoids, and lipid peroxidation, regardless of the temperature (25 and 30°C), were identified as sensitive biochemical indicators for the detection of physiological quality of purple corn seedlings subjected to NaCl.

Resumo: A técnica de análise de imagens multiespectrais para detecção da fluorescência de clorofila (FC) em sementes de soja foi estudada com o objetivo de avaliar a relação entre os sinais da FC e o seu potencial fisiológico. Para dois cultivares, BMX Desafio RR 8473 RSF e 96R10 IPRO, foram utilizados oito tratamentos correspondendo a 0%, 2%, 4%, 6%, 8%, 10%, 12% e 14% de sementes esverdeadas, os quais foram submetidos a diferentes testes de qualidade. Inicialmente, a FC das sementes foi determinada utilizando-se espectros de 660 nm e 730 nm e com as mesmas sementes foram realizados os testes de germinação, condutividade elétrica, envelhecimento acelerado com solução saturada de NaCl, tetrazólio e análise computadorizada de imagens de plântulas (Vigor-S). Foi utilizado o delineamento inteiramente casualizado, com as repetições de cada tratamento. Com o software R®, os dados dos testes de germinação, de vigor e de FC das sementes foram submetidos à análise de variância (ANOVA) e as médias agrupadas pelo teste de Skott-Knott (p ≤ 0,05). Os coeficientes de correlação linear de Pearson (r) foram calculados para todas as combinações entre as avaliações com significância dos valores r, determinados pelo teste t (p ≤ 0,05) e procedeu-se a análise multivariada de componentes principais. Aumentos proporcionais de sementes esverdeadas contribuem para o aumento nos sinais de fluorescências de clorofila e tem correlação negativa com a qualidade fisiológica das sementes, de modo que níveis acima de 4% de sementes esverdeadas nas amostras resultam em perdas acentuadas no potencial fisiológico. Portanto, a fluorescência de clorofila detectada por intermédio de imagens multiespectrais tem relação inversa com o potencial fisiológico de sementes de soja.

Abstract: The multispectral image analysis technique to detect chlorophyll fluorescence (CF) in soybean seeds was studied to assess the relationship between CF signals and seed physiological potential. Eight treatments, corresponding to 0%, 2%, 4%, 6%, 8%, 10%, 12%, and 14% green seeds, were used on two cultivars, BMX Desafio RR 8473 RSF and 96R10 IPRO, which passed through different seed quality tests. Initially, the CF of the seeds was determined using 660 nm and 730 nm spectra, and then the germination, electrical conductivity, accelerated aging with saturated NaCl solution, tetrazolium, and computerized seedling image analysis (Vigor-S) tests were performed on the same seeds. A completely randomized design was used, as well as replications of each treatment. Analysis of variance (ANOVA) was performed on the data from germination, vigor, and CF tests using the R® software, and the means were grouped by the Scott-Knott test (p ≤ 0.05). Pearson’s linear correlation coefficients (r) were calculated for all combinations among the evaluations with significance of the r values determined by the t-test (p ≤ 0.05), and multivariate analysis of the principal components was performed. Proportional increases in green seeds contribute to an increase in chlorophyll fluorescence signals and have a negative correlation with seed physiological quality; levels above 4% green seeds in the samples result in marked losses in physiological potential. Therefore, the chlorophyll fluorescence detected through multispectral images is inversely related to the physiological potential of soybean seeds.

Resumo: O tratamento químico de sementes de soja é muito importante para assegurar o sucesso no estabelecimento da lavoura. Contudo, deve-se ter atenção a problemas, como a fitotoxicidade de combinações de produtos, capazes de reduzir o desempenho fisiológico. O uso de recursos computacionais para identificar efeitos fitotóxicos têm potencial para integrar às etapas do controle de qualidade de sementes tratadas. O objetivo foi verificar se a análise computadorizada de imagens de plântulas permite avaliar de forma eficiente e simplificada a fitotoxicidade do tratamento químico de sementes de soja. As sementes de dois lotes foram tratadas com fungicidas, inseticidas, micronutrientes e combinações entre eles, além de polímero e pó secante (recobrimentos). Após o tratamento químico, as sementes foram avaliadas quanto a germinação, primeira contagem de germinação, emergência de plântulas em areia, envelhecimento acelerado e o desempenho de plântulas com e sem a correção de regiões não demarcadas automaticamente (Vigor-S). Verificamos alta correlação dos parâmetros do Vigor-S com os testes tradicionais para detecção de efeitos fitotóxicos do tratamento químico, independente da correção feita no sistema. A análise computadorizada de imagens de plântulas é um recurso eficiente e de alta sensibilidade para avaliar a fitotoxicidade do tratamento químico de sementes de soja.

Abstract: Chemical treatment of soybean seeds is very important to ensure successful crop establishment. However, problems such as phytotoxicity of product combinations that can reduce seed physiological performance require attention. The use of computational resources has shown potential in identifying phytotoxic effects and contributing to the steps of quality control of treated seeds. The aim of this study was to determine if computerized image analysis of seedlings enables the phytotoxicity of chemical treatment of soybean seeds to be assessed in an effective and simplified manner. Samples from two soybean seed lots were treated with fungicides, insecticides, micronutrients, and their combinations, as well as with polymer and drying powder (coatings). After chemical treatment, the seeds were evaluated for germination, first germination count, seedling emergence in sand, accelerated aging, and seedling performance with and without the correction of regions not automatically demarcated (Vigor-S). We found high correlation of the Vigor-S parameters with the traditional tests for detection of phytotoxic effects of chemical treatment, regardless of correction made in the system. Computerized image analysis of seedlings is an effective and highly sensitive resource for evaluating possible phytotoxicity effects due to chemical treatment of soybean seeds.

Resumo: A inclusão do uso de ferramentas computacionais no controle da qualidade de sementes tem-se destacado com o intuito de auxiliar em maior assertividade na caracterização de lotes de maior potencial. Assim, o objetivo deste estudo foi investigar por meio de uma abordagem computacional a análise de parâmetros morfológicos que caracterizem a emergência da raiz primária na avaliação do vigor de sementes de tomate. Para isso, cinco lotes de sementes foram analisados quanto a sua germinação e vigor (emergência de plântulas e análise de imagens de plântulas). Em paralelo, a emergência da raiz primária foi analisada utilizando visão computacional assistida; as imagens registradas durante o progresso de germinação foram processadas com o software ImageJ® para obtenção dos parâmetros de relação de aspecto e área da semente. As diferenças de vigor entre lotes de sementes de tomate podem ser identificadas com base na emergência da raiz primária e o processamento computacional das imagens baseado na relação de aspecto apresenta-se como um procedimento eficiente para a caracterização da emergência da raiz primária na avaliação do vigor de sementes de tomate.

Abstract: The use of computational tools has become notable in seed quality control to assist in confirming seed lots of higher potential. Thus, the aim of this study was to use a computational approach to investigate analysis of morphological parameters that characterize primary root emergence in evaluation of tomato seed vigor. For that purpose, five seed lots were analyzed for germination and vigor (seedling emergence and analysis of seedling images). A parallel analysis of primary root emergence was made using computer-assisted imaging; the images recorded as germination proceeded were processed with the ImageJ® software to obtain aspect ratio and seed area parameters. Vigor differences among tomato seed lots can be identified based on primary root emergence, and computer image processing based on aspect ratio proves to be an efficient procedure to characterize emergence of the primary root in evaluation of tomato seed vigor.

Resumo: A ocorrência de danos mecânicos se constitui um problema sério para o potencial fisiológico de sementes de soja, principalmente quando combinado com tratamento químico. O objetivo do trabalho foi investigar os efeitos do tratamento químico sobre o potencial fisiológico de sementes de soja com níveis crescentes de danos mecânicos. Sementes de dois lotes (cv. M6410 IPRO), apresentando diferenças de vigor, foram submetidas a cinco níveis de danos mecânicos (zero, um, dois, três e quatro impactos) provocados de forma controlada. Após a caracterização do efeito dos impactos sobre a integridade física das sementes (raios X, microtomografia computadorizada de raios X, tetrazólio e hipoclorito de sódio), estas foram submetidas a quatro combinações de tratamento químico com fungicidas (carbendazim e thiram), inseticidas (imidaclopride e tiocarbe), micronutrientes (cobalto e molibdênio), polímero (Peridiam®) e pó secante (Talkum Gloss®). A germinação e o vigor das sementes foram avaliados sessenta dias após o tratamento químico. Constatou-se que aumento progressivo de danos mecânicos, especialmente aqueles que provocam fissuras no tegumento, proporciona redução no potencial fisiológico de sementes de soja e aumenta a sua sensibilidade ao efeito fitotóxico do tratamento químico. A integridade física do tegumento é determinante para o sucesso de tecnologias utilizadas para o tratamento químico de sementes.

Abstract: Mechanical damage is a serious problem for the physiological potential of soybean seeds, especially when combined with chemical treatment. The aim of this study was to investigate the effects of chemical treatment on the physiological potential of soybean seeds with increasing levels of mechanical damage. Soybean seeds (cv. M6410 IPRO) of two lots with differences in vigor were subjected to five levels of mechanical damage (zero, one, two, three, and four impacts) brought about in a controlled manner. After characterization of the effect of the impacts on seed physical integrity (X-ray, X-ray microtomography, tetrazolium, and sodium hypochlorite), the seeds were subjected to four combinations of chemical treatment with fungicides (carbendazim and thiram), insecticides (imidacloprid and thiodicarb), micronutrients (cobalt and molybdenum), polymer (Peridiam®), and drying powder (Talkum Gloss®). Seed germination and vigor were evaluated sixty days after chemical treatment. A progressive increase in mechanical damage, especially that which causes cracks in the seed coat, reduces the physiological potential of soybean seeds and increases their sensitivity to the phytotoxic effect of the chemical treatment. The physical integrity of the seed coat is crucial for the success of technologies used for chemical seed treatment.

ABSTRACT Spinach seeds are sensitive to high temperatures during germination and plant growth. It is known that seed priming with water or with seaweed extract (SWE) may enhance germination and seedling growth. The objective of this study was to evaluate the effects of seed priming with SWE (Ascophyllum nodosum) on the germination, seedling growth and antioxidant capacity of spinach seedlings under conditions of heat stress. Five concentrations of SWE (0.0, 0.15, 0.30, 0.60 and 1.2%) were used for priming the seeds under two temperatures (15 and 30 °C). Seeds primed with 0.3% SWE had the greatest activity of antioxidant metabolism and showed improved germination percentage, germination speed and seedling vigor under conditions of heat stress (30 °C) compared to nonprimed controls. Hydropriming and priming with 0.3% SWE resulted in lower contents of hydrogen peroxide (H2O2) and malondialdehyde (MDA) under heat stress than control (nonprimed spinach seeds). This study showed that seed priming with SWE was effective to mitigate stress due to high temperatures and to improve spinach seed germination and seedling vigor.

Resumo: O melão é uma olerícola de importância alimentícia e nutricional, cujo cultivo vem crescendo mundialmente. Em função disso, investimentos em tecnologias serão necessários, especialmente no tocante à qualidade de sementes utilizadas no estabelecimento de novas áreas. Objetivou-se verificar a eficiência do Sistema de Análise Automatizada do Vigor de Sementes (Vigor-S) na avaliação do potencial fisiológico de sementes de melão. Utilizou-se oito lotes de sementes, quatro do híbrido Supreme e quatro do Premier. O potencial fisiológico das sementes foi avaliado por meio de testes já indicados para a análise da qualidade de sementes da cultura do melão, juntamente a análise de imagens pelo software Vigor-S, que englobou as análises de plântulas dos testes de germinação e envelhecimento acelerado em solução saturada de NaCl. O experimento foi conduzido em delineamento inteiramente casualizado, com cinco repetições. Os resultados indicaram eficiência do Vigor-S, sobretudo quando este foi utilizado juntamente ao teste de envelhecimento acelerado em solução saturada de NaCl, com resultados semelhantes aos obtidos nos testes de vigor tradicionais. Dessa forma, concluiu-se que a Análise Automatizada do Vigor de Sementes (Vigor-S) se mostrou eficiente na avaliação do potencial fisiológico de sementes de melão.

Abstract: Melon is a vegetable crop of food and nutritional importance whose cultivation is growing worldwide. In this sense, investments in technologies are necessary, especially regarding the quality of seeds used in the establishment of new areas. This study aimed to verify the effectiveness of the Automated Seed Vigor Analysis System (Vigor-S) in the evaluation of the physiological potential of melon seeds. Eight seed lots (four lots of the hybrid Supreme and four of the hybrid Premier) were used. The physiological potential of the seeds was evaluated through tests indicated for analyzing the quality of melon seeds associated with the image analysis by using the software Vigor-S, which included the analysis of seedlings from the germination test and accelerated aging in saturated NaCl solution. The experiment was conducted in a completely randomized design, with five replications. The results indicated the effectiveness of Vigor-S, especially when it was used associated with the accelerated aging test in saturated NaCl solution, with results similar to those obtained in traditional vigor tests. Thus, the Automated Seed Vigor Analysis System (Vigor-S) was effective in evaluating the physiological potential of melon seeds.

ABSTRACT: This study was performed to associate specific morphological parameters, defined by X-ray images, with seed performance of okra (Abelmoschus esculentus (L.) Moench) during maturation. Fruits of cultivar Santa Cruz 47 at different developmental stages were collected at five-day intervals (from 5 to 65 days after anthesis) and water content, dry matter, germination and vigor were determined in seeds extracted immediately after each harvest or after temporary storage for seven days. X-ray tests were also performed after each harvest and the images were analyzed by ImageJ® software to produce data of aspect ratio (relation between major and minor axes of the ellipse surrounding the seed perimeter) and percentage of free space area in the inner seed cavity. Physiological maturity (maximum accumulation of dry matter) was reached at 30 days after anthesis (DAA), when seed water content was 56.6 %. Seed germination and vigor increased during maturation, achieving the maximum at 50 DAA. Seeds showed morphological changes during maturation, becoming more spherical (aspect ratio near 1.0); at the same time, the free space available in the inner cavity of the seed decreased. This parameter can be successfully used as a marker of physiological maturity when values equal or lower than 5 % are reached.

RESUMO A identificação de testes rápidos e eficientes para a avaliação do vigor de lotes de sementes de gramíneas forrageiras são desejáveis nos programas de controle de qualidade das empresas deste setor. Sendo assim, objetivou-se avaliar a eficiência de testes de vigor na qualidade fisiológica de sementes de Panicum maximum, cv. Mombaça, para a diferenciação dos lotes e previsão de emergência de plântulas em campo. Dezenove lotes de sementes foram submetidos às avaliações de teor de água, germinação, primeira contagem, índice de velocidade de germinação, emergência de plântulas em areia, primeira contagem de emergência de plântulas em areia, comprimento de raiz e parte aérea de plântulas, emergência de plântulas em campo e análise computadorizada de imagens de plântulas obtidas por meio do Software SVIS®. O delineamento experimental utilizado foi o inteiramente casualizado para os testes realizados em laboratório e blocos ao acaso para o teste de emergência em campo. Os dados foram submetidos à análise de variância e as médias comparadas pelo teste de Scott Knott a 5% de probabilidade. Realizou-se a análise de agrupamento dos lotes de sementes, e de componentes principais. O índice de uniformidade, avaliado por meio da análise de imagens e pelo teste de comprimento de raiz, é eficiente na avaliação do potencial fisiológico de sementes de P. maximum, cv. Mombaça, fornecendo informações semelhantes à emergência de plântulas em campo.

ABSTRACT Identifying fast and efficient tests to evaluate the vigor of forage grass seed lots is desirable in the quality control programs of the companies in this sector. Thus, the objective was to evaluate the efficiency of vigor tests on the physiological quality of seeds of Panicum maximum, cv. Mombasa, for the differentiation of lots and prediction of seedling emergence in the field. Nineteen seed lots were subjected to evaluations of moisture content, germination, first count, germination speed index, seedling emergence in sand, first count of seedling emergence in sand, seedling root and shoot lengths, seedling emergence in the field and computerized analysis of seedling images obtained through SVIS® software. The experimental design was completely randomized for the tests performed in the laboratory and randomized blocks for the emergence test in the field. The data were subjected to analysis of variance and the means were compared by Scott-Knott test at 5% probability level. Cluster analysis of seed lots and principal component analysis were performed. The uniformity index, evaluated by image analysis and by the root length test, is efficient in evaluating the physiological potential of seeds of Panicum maximum, cv. Mombasa, providing information similar to those obtained with the test of seedling emergence in the field.

RESUMO A análise de imagens tem sido usada recentemente para avaliar a qualidade das sementes e elucidar alguns aspectos da fisiologia das sementes, incluindo testes de raios X e outros recursos. O objetivo deste estudo foi examinar se o raios X pode ser utilizado para detectar anormalidades físicas e relacionar sua ocorrência com o potencial fisiológico de sementes de abóbora tipo tetsukabuto. Os frutos foram colhidos em diferentes estádios de maturação (15, 30, 45, 60 e 75 dias após a antese - DAA) e armazenados por 20 dias. As sementes foram radiografadas com intensidade de 25 kV por 40 segundos e em seguida foi realizado um teste de germinação em alternância de 20-30 ºC. Após quatro e oito dias, foram registrados percentuais de plântulas normais e anormais e sementes mortas. Os resultados de ambas as contagens foram avaliados comparativamente com imagens da morfologia interna de cada semente, obtidas por meio de teste de raios X. A análise radiográfica é eficaz na detecção de sementes de abóbora inteiras, malformadas e vazias. A utilização da técnica de raios X é eficiente na detecção de sementes cheias, mal formadas e vazias de abóbora, e ainda confirma os resultados obtidos nos testes fisiológicos, onde as sementes provenientes de frutos colhidos aos 60 DAA e armazenados por 20 dias apresentaram uma qualidade superior.

ABSTRACT Analysis of images has been recently used in order to both assess seed quality and elucidate some aspects of seed physiology, including X-ray tests and other resources. The objective of this study was to examine whether the X-ray may be successfully used to detect physical abnormalities, and relate their occurrence with physiological potential of tetsukabuto type squash seeds. Fruits were harvested at different maturation stages (15, 30, 45, 60 and 75 days after anthesis - DAA) and temporarily or not stored for 20 days. Seeds were radiographed using an intensity of 25 kV for 40 seconds and then germinated under alternating temperatures of 20-30 ºC. After four and eight days, percentages of normal and abnormal seedlings and dead seeds were recorded. Results of both counts were evaluated comparatively with images of the internal morphology of each seed, obtained by means of X-ray test. The radiographic analysis is effective in detecting full, malformed and empty squash seeds. This confirmed information provided by the germination test, in which seeds harvested from 60 DAA and stored for 20 days were better in physiological potential.

RESUMO O teste de raios X permite a visualização das estruturas internas das sementes de modo não destrutivo e individualizado, possibilitando o diagnóstico de causas da baixa germinação e pureza de um lote. O objetivo do trabalho foi avaliar a qualidade das sementes de Brachiaria brizantha utilizando-se o teste de raios X e o efeito das etapas de beneficiamento. As sementes foram amostradas antes do processamento e após a saída da máquina de ar e peneiras, primeira e segunda mesa gravitacional. As sementes foram avaliadas quanto ao teor de água, pureza, peso de mil sementes, germinação e pelo teste de raios X. O delineamento experimental utilizado foi o inteiramente casualizado com quatro repetições. O teste de raios X permite a identificação de sementes cheias, com tecido deteriorado, mal formadas, com danos mecânicos e espiguetas vazias de B. brizantha. O beneficiamento não causou dano mecânico nas sementes de B. brizantha. A análise de raios X pode ser utilizada para o monitoramento da qualidade, fornecendo informações que podem ajudar no ajuste das máquinas de beneficiamento.

ABSTRACT The X-ray test permits the visualization of the internal structures of seeds in a non-destructive way making thus possible the diagnosis of causes of seed low germination and purity. The objective of this project was to evaluate the quality of Brachiaria brizantha seeds by means of the X-ray test and the effect of the processing stage. The seeds were sampled before processing and after going through the air and screen machine, and the first and the second gravity tables. Seeds were evaluated as to water content, purity, weight of a thousand seeds, germination, and the X-ray test. The treatment replications were distributed according to a complete random design with four replications. The X-ray test permit to verify the completely full seeds as well as deteriorated, hollow, mechanically damaged seeds and empty spikelets. The processing procedure caused no damage to the seeds. The analysis by means of X-ray is a quality control procedure resulting in information that can be used in the adjustments of processing machines.