INTRODUÇÃOO avanço da área de cultivo de soja vem ocorrendo em todas as regiões do País (Conab 2014), especialmente no Nordeste, que possui a maior concentração de solos salinos e baixos índices pluviométricos (Cirilo et al. 2010).Os solos salinizados ocorrem em condições topográficas que não favorecem uma drenagem eficiente, principalmente onde o manejo da irrigação é inadequado ou a água utilizada apresenta problemas de qualidade (Oliveira 1997).A salinidade do solo pode comprometer a germinação das sementes pela diminuição do potencial osmótico externo, impedindo a absorção de água, ou por meio dos efeitos tóxicos da absorção de íons ABSTRACT RESUMOcomo o Na + e o Cl - (Murillo-Amador et al. 2002, Khajeh-Hosseini et al. 2003. Os íons e o estresse osmótico são responsáveis tanto pela inibição quanto pela demora na germinação e estabelecimento das plântulas (Almansouri et al. 2001). Se comparado ao estresse salino, o problema da seca é ainda mais abrangente e economicamente muito prejudicial à agricultura (Pimentel 1999). Para a cultura da soja, os estresses salino e hídrico provocam efeitos negativos na germinação e vigor das sementes e, em condições de estresses ainda mais severas, as sementes de menor vigor são as mais suscetíveis (Braccini et al. 1996).Em diversos trabalhos tem sido avaliado o efeito do estresse hídrico induzido por NaCl na germinação e no crescimento de plântulas (Braccini A importância do tamanho das sementes tem sido relatada para várias espécies, visto que pode afetar a sua germinação e o vigor das plântulas, principalmente sob condições de estresse. Objetivou-se avaliar o efeito do tamanho das sementes na germinação e crescimento inicial de plântulas de soja (cultivares M9144RR e M8527RR), sob condições de estresse hídrico e salino. O estresse hídrico foi induzido por manitol e o salino por cloreto de sódio. Para a avaliação do efeito dos tratamentos, as sementes foram submetidas ao teste de germinação, primeira contagem de germinação e crescimento de plântulas. Utilizou-se delineamento inteiramente casualizado, com quatro repetições. Houve redução na germinação e no vigor das sementes de soja com a diminuição do potencial osmótico. Não foi observado efeito do tamanho das sementes sobre a germinação e comprimento das plântulas, porém, as sementes de maior tamanho resultaram em plântulas com maior massa seca, mesmo quando submetidas a condições de estresse hídrico e salino. PALAVRAS-CHAVE:Glycine max; potencial hídrico; qualidade de sementes.Water and salt stress in soybean seeds classified in different sizesThe importance of seed size has been reported for many species, since it may affect seed germination and seedling vigor, especially under stress conditions. This study aimed at evaluating the effect of seed size on the germination and initial growth of soybean seedlings (M9144RR and M8527RR cultivars), under water and salt stress conditions. Water stress was induced by mannitol and salt stress by sodium chloride. The seeds were submitted to the germination test, first germination co...

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Non-destructive and high performance analyses are highly desirable and important for assessing the quality of forest seeds. The aim of this study was to relate parameters obtained from semi-automated analysis of radiographs of Leucaena leucocephala seeds to their physiological potential by means of multivariate analysis. To do so, seeds from five lots collected from parent trees from the region of Viçosa, MG, Brazil, were used. The study was carried out through analysis of radiographic images of seeds, from which the percentage of damaged seeds (predation and fungi), and measurements of area, perimeter, circularity, relative density, and integrated density of the seeds were obtained. After the X-ray test, the seeds were tested for germination in order to assess variables related to seed physiological quality. Multivariate statistics were applied to the data generated, with use of principal component analysis (PCA). X-ray testing allowed visualization of details of the internal structure of seeds and differences regarding density of seed tissues. Semi-automated analysis of radiographic images of Leucaena leucocephala seeds provides information on seed physical characteristics and generates parameters related to seed physiological quality in a simple, fast, and inexpensive manner.

RESUMOSubmetido em 16/12/2015 e aprovado em 05/05/2016. 1 Este trabalho é parte da dissertação de mestrado da primeira autora. 2 Universidade Federal de Viçosa, Departamento de Fitotecnia, Viçosa, Minas Gerais, Brasil. dssalice@gmail.com; laercio.silva@ufv.br; aracycamilla@hotmail.com; neysakiyama@gmail.com; 3 Embrapa Café, Brasília, Distrito Federal, Brasil. williams Specialty coffees can be differentiated in various ways, including the environmental conditions in which they are produced and the sensory composition of the drink. This study aimed to evaluate the effect of altitude, slope exposure and fruit color on the sensory attributes of cafes of the region of Matas de Minas. Sampling points were georeferenced in four altitude ranges (< 700 m; 700 < x > 825 m, 825 < x < 950 m and > 950 m) of the coffee crop; two fruit colors of var. Catuaí (yellow and red); and two slope exposures (North-facing and South-facing). Coffee fruit at the cherry stage were processed and submitted to sensory analysis. The sensory attributes evaluated were overall perception, clean cup, balance, aftertaste, sweetness, acidity, body and flavor, which made up the final score. The scores were examined by ANOVA and means were compared by the Tukey test (p < 0.05). From the sensory standpoint, coffee fruits of both colors are similar, as well as the coffees from both slope exposures when these factors were analyzed separately. However, at higher altitudes, Yellow Catuaí produces coffees with better sensory quality. Similarly, coffees from North-facing slopes, at higher altitudes produce better quality cup. The altitude is the main factor that interferes with coffee quality in the area. All factors together contribute to the final quality of the beverage produced in the region of Matas de Minas. Keywords Análise sensorial dos cafés especiais da região das Matas de Minas cultivados em diferentes condições ambientaisOs cafés especiais podem ser diferenciados por diversas formas, incluindo as condições ambientais em que são produzidos e a composição sensorial da bebida. Objetivou-se avaliar neste trabalho o efeito dos fatores altitude, face de exposição solar e cor do fruto nos atributos sensoriais dos cafés da região das Matas de Minas. Nas lavouras, pontos amostrais foram georreferenciados em quatro extratos de altitude (< 700 m; 700 < x > 825 m, 825 < x < 950 m e > 950 m); duas cores de fruto da variedade Catuaí (amarelo e vermelho); e duas faces de exposição solar (Noroeste e Sudeste ). Foram utilizados cafés no estádio "cereja", que foram beneficiados e submetidos à análise sensorial. Foram avaliados os atributos sensoriais percepção geral, bebida limpa, balanço, retrogosto, doçura, acidez, corpo e sabor, compondo assim o escore final. As notas foram submetidas à ANOVA e as médias comparadas pelo teste de Tukey (p < 0,05). Do ponto de vista sensorial, os frutos de café de ambas as cores se mostram semelhantes, assim como os cafés localizados em ambas as faces quando esses fatores foram analisados isoladamente. Entretanto, em ...

The need to optimize seed quality assessment using new, more accessible, and modern computational resources has led to the emergence of new tools. In this paper, we introduce SeedCalc, a new R software package developed to process germination and seedling length data. The functions included in SeedCalc allow fast and efficient data processing, offering greater reliability to the variables generated and facilitating statistical analysis itself since the data are already processed with the appropriate structure to be statistically analyzed in the R software. SeedCalc is available free of charge at https://CRAN.R-project.org/package=SeedCalc.

Optical sensors combined with machine learning algorithms have led to significant advances in seed science. These advances have facilitated the development of robust approaches, providing decision-making support in the seed industry related to the marketing of seed lots. In this study, a novel approach for seed quality classification is presented. We developed classifier models using Fourier transform near-infrared (FT-NIR) spectroscopy and X-ray imaging techniques to predict seed germination and vigor. A forage grass (Urochloa brizantha) was used as a model species. FT-NIR spectroscopy data and radiographic images were obtained from individual seeds, and the models were created based on the following algorithms: linear discriminant analysis (LDA), partial least squares discriminant analysis (PLS-DA), random forest (RF), naive Bayes (NB), and support vector machine with radial basis (SVM-r) kernel. In the germination prediction, the models individually reached an accuracy of 82% using FT-NIR data, and 90% using X-ray data. For seed vigor, the models achieved 61% and 68% accuracy using FT-NIR and X-ray data, respectively. Combining the FT-NIR and X-ray data, the performance of the classification model reached an accuracy of 85% to predict germination, and 62% for seed vigor. Overall, the models developed using both NIR spectra and X-ray imaging data in machine learning algorithms are efficient in quickly, non-destructively, and accurately identifying the capacity of seed to germinate. The use of X-ray data and the LDA algorithm showed great potential to be used as a viable alternative to assist in the quality classification of U. brizantha seeds.

New computer vision solutions combined with artificial intelligence algorithms can help recognize patterns in biological images, reducing subjectivity and optimizing the analysis process. the aim of this study was to propose an approach based on interactive and traditional machine learning methods to classify soybean seeds and seedlings according to their appearance and physiological potential. in addition, we correlated the appearance of seeds to their physiological performance. images of soybean seeds and seedlings were used to develop models using low-cost approaches and free-access software. The models developed showed high performance, with overall accuracy reaching 0.94 for seeds and seedling classification. The high precision of the models that were developed based on interactive and traditional machine learning demonstrated that the method can easily be used to classify soybean seeds according to their appearance, as well as to classify soybean seedling vigor quickly and non-subjectively. the appearance of soybean seeds is strongly correlated with their physiological performance.

The effects of NO donors on germination under saline stress have been much investigated for many species, however, there are reports that the effect caused by donors are effects of cyanide present. The aim of this study was to evaluate the effects of sodium nitroprusside (SNP) on germination, antioxidative system and lipid peroxidation of Senna macranthera seeds under saline stress. The osmotic potentials of -0.4 and -0.5 MPa of NaCl were used, as well as the concentration of 100 μM of sodium nitroprusside, inactive sodium nitroprusside. Germination rate, imbibition curves, antioxidant enzyme activity, lipid peroxidation, and protein content were evaluated. Similar effects were observed for sodium nitroprusside and inactive sodium nitroprusside, indicating that these effects were related to the release of the cyanide present in sodium nitroprusside. The sodium nitroprusside (SNP) improves the germination of Senna macranthera seeds under salt stress conditions, through release of cyanide. The cyanide favored germination, reducing lipid peroxidation and increasing the activity of the antioxidant enzymes.