Abstract: Creation, adjustments and adoption of tests and tools that help in the prediction of seed storability have been highly demanded. Therefore, this work aimed to analyze the efficiency of different artificial aging times in predicting the performance of soybean seeds after storage, using the GGE biplot method. Seeds of six genotypes were subjected to storage, under refrigerated and non-refrigerated conditions, and artificial aging, being artificially aged for periods of 0, 48, 96 and 144 hours. Seeds freshly harvested and after natural and artificial aging were subjected to germination and vigor tests. The experiments were analyzed separately, using means test, regression analysis and model identity test, and together, using the GGE biplot method. Artificial aging at a temperature of 41 °C for 96 hours has the potential to be used to predict the performance of soybean seeds after eight months of storage. The GGE biplot is a method that can be used as a tool to analyze the relationships between aging environments and visualize the ranking of genotypes regarding the performance of seeds subjected to natural and artificial aging.

Resumo: Tem sido altamente requerida a elaboração, ajustes e adoção de testes e ferramentas que auxiliem na predição da armazenabilidade de sementes. Diante disso, este trabalho teve por objetivo analisar a eficiência de diferentes tempos de envelhecimento artificial na predição do desempenho das sementes de soja após o armazenamento, utilizando-se o método GGE biplot. Sementes de seis genótipos foram submetidas ao armazenamento, sob condição refrigerada e não refrigerada, e envelhecimento artificial, sendo envelhecidas artificialmente pelos períodos de 0, 48, 96 e 144 horas. As sementes recém-colhidas e após o envelhecimento natural e artificial foram submetidas a testes de germinação e vigor. Os experimentos foram analisados separadamente, por meio de teste de médias, análise de regressão e teste de identidade de modelos, e em conjunto, utilizando-se o método GGE biplot. O envelhecimento artificial, à temperatura de 41 °C por 96 horas apresenta potencial para ser utilizado na predição do desempenho de sementes de soja após oito meses de armazenamento. O GGE biplot é um método que pode ser utilizado como ferramenta para analisar as relações entre os ambientes de envelhecimento e visualizar o ranqueamento dos genótipos quanto ao desempenho das sementes submetidas ao envelhecimento natural e artificial.

ABSTRACT. Weathering deterioration affects seed quality, especially in areas with excessive rainfall. This study aimed to evaluate the oxidative stress, physiological quality, and protein metabolism of seeds of different soybean cultivars under weathering deterioration at the pre-harvest phase. Six soybean cultivars (BMX Apolo, DM 6563, NS 5959, NA 5909, BMX Potência, and TMG 1175) were subjected to simulated rainfall at the R8 stage. Each level was divided into two applications at 72-h intervals: 60 mm (30 + 30), 120 mm (60 + 60), and 180 mm (90 + 90). Then, the seeds were harvested and evaluated for physiological potential, antioxidative enzymes, hydrogen peroxide, malondialdehyde, proteins, and protease activity. The simulated rainfall allowed the variation in seed moisture, promoting a significant reduction in germination and seed vigor, especially at 120 and 180 mm levels. There were also reductions in antioxidative enzyme activity with weathering deterioration (mainly for catalase, ascorbate peroxidase, and peroxidase), accumulation of hydrogen peroxide and malondialdehyde, and reductions in protein content and protease activity. The proposed rainfall system is efficient in inducing weathering deterioration during the pre-harvest phase and its deleterious effects. Weathering deterioration in soybean seeds in the pre-harvest stage is directly influenced by genotype.

ABSTRACT Water stress during wheat seed germination and seedling establishment for affect the percentage and speed of germination. Silicon (Si) is related to plant tolerance to different types of stress, then the application of this nutrient in the mother plant during seed production could contribute to the improvement of the seed quality and, consequently, its tolerance to stress. The aim was to evaluate the effect of foliar application of silicon on the tolerance of wheat seeds, produced under different irrigation levels, to water stress during germination and initial seedling growth. Wheat seeds were produced under three irrigation depths (0, 50 and 100% of the total required irrigation) applied after the anthesis. The silicon was supplied in two doses by foliar application (0 and 5 mM of Si). The germination and seedling growth were performed under water stress induced by PEG 6000 at the -0.2; -0.4; -0.6 MPa osmotic potentials. In addition, in the control only distilled water was used. The reduction of the osmotic potential reduced seed germination, germination speed and seedling growth. Irrigation depths, as well as foliar application of Si, during seed production did not influence the physiological quality and tolerance of seeds to water stress during germination.

Resumo: Métodos não-destrutivos e de alto desempenho têm sido desenvolvidos para avaliação da qualidade de sementes. O objetivo deste estudo foi relacionar parâmetros obtidos a partir da análise gratuita e automatizada de radiografias digitais de sementes de melão híbrido com o seu potencial fisiológico. Foram utilizadas amostras de sementes comerciais de três cultivares híbridas de melão (Cucumis melo L.), cada uma representada por três lotes. Foram obtidas imagens radiográficas das sementes, das quais foram geradas determinações de área, perímetro, circularidade, densidade relativa, densidade integrada e preenchimento da cavidade interna de sementes, por meio de uma macro (PhenoxXray) desenvolvida para o software ImageJ®. Após o teste de raios-X, as sementes foram submetidas ao teste de germinação, a partir do qual foram obtidas variáveis relacionadas à qualidade fisiológica. Observou-se variabilidade entre lotes para as características físicas e fisiológicas. Os resultados demonstraram que o uso da macro PhenoXray permite a fenotipagem em larga escala das radiografias de sementes de maneira simples, rápida, consistente e totalmente gratuita. A metodologia é eficiente na obtenção de dados morfométricos e de integridade tecidual em sementes de melão, e os parâmetros gerados apresentam estreita relação com atributos fisiológicos da qualidade das sementes.

Abstract: Non-destructive and high throughput methods have been developed for seed quality evaluation. The aim of this study was to relate parameters obtained from the free and automated analysis of digital radiographs of hybrid melons’ seeds to their seeds’ physiological potential. Seeds of three hybrid melon (Cucumis melo L.) cultivars from commercial lot samples were used. Radiographic images of the seeds were obtained, from which area, perimeter, circularity, relative density, integrated density and seed filling measurements were generated by means of a macro (PhenoXray) developed for ImageJ® software. After the X-ray test, seed samples were submitted to the germination test, from which variables related to the physiological quality of the seeds were obtained. Variability between lots was observed for both physical and physiological characteristics. Results showed that the use of the PhenoXray macro allows large-scale phenotyping of seed radiographs in a simple, fast, consistent and completely free way. The methodology is efficient in obtaining morphometric and tissue integrity data of melon seeds and the generated parameters are closely related to physiological attributes of seed quality.