Seed treatment with micronutrients is a crucial strategy for providing early seedling supply during development, and is commonly employed in soybean cultivation. However, responses to micronutrient treatment may vary based on seed vigor levels. Therefore, this study aimed to assess the potential of hyperspectral imaging combined with preprocessing and machine learning, compared to X-ray fluorescence spectroscopy, in evaluating the dynamics of micronutrient uptake during the germination of soybean seeds with varying levels of vigor. Two seed lots with differing levels of vigor were utilized for the analysis. The absorption of micronutrients by the seeds was evaluated using X-ray fluorescence spectroscopy (XRF), microprobe X-ray fluorescence spectroscopy (μ-XRF) and hyperspectral imaging (HSI) in two regions of interest (cotyledons and the embryonic axis). Artificial neural network (ANN), decision tree (DT) and partial least squares–discriminant analysis (PLS-DA) classification models, along with the Savitzky–Golay (SG), standard normal variation (SNV) and multiplicative scatter correction (MSC) methods, were employed to determine seed vigor based on the impact of micronutrient treatment. XRF identified higher concentrations of micronutrients in the treated seeds, with zinc being the predominant element. μ-XRF analysis revealed that a significant proportion of the micronutrients remained adhered to the hilum and seed coat, irrespective of seed vigor. The PLS-DA classification model using spectral data exhibited higher accuracy in classifying soybean seeds with high and low vigor, regardless of seed treatment with micronutrients and the analyzed region.

Cobalt, molybdenum, and nickel are elements directly involved in biological nitrogen fixation in legume plants. However, there is a lack of information about the effects of the interaction among these elements on seed vigor and plant development. This study aimed to evaluate the effects of different doses of these elements on soybean seeds with higher and lower vigor, focusing on nitrogen metabolism and plant development under controlled conditions. The two lots of soybean seeds (higher and lower vigor) were treated with doses of 0, 2, 4, 6, and 8 mL kg⁻¹ of seeds of a liquid commercial product composed of cobalt, molybdenum, and nickel. At the full flowering stage, urease and nitrogenase activities, dry biomass of shoots, roots, and nodules, nitrogen concentration in shoots, plant height, number of nodules, and the efficiency of biological nitrogen fixation (measured by nitrogen-15 isotopic ratio) were assessed. Urease activity increased by 191% in high-vigor seed plants and 65% in low-vigor seed plants. Nitrogenase activity was higher in higher-vigor plants. Nodule dry biomass increased by 42% in lower-vigor plants compared to the control treatment, while in higher-vigor plants, it decreased with increasing doses. Shoot biomass was 30% higher than the control at the 2 mL kg⁻¹ dose. In general, the best responses to the application of the elements in the evaluated variables were observed with the doses of 2 and 4 mL kg⁻¹. It is concluded that the appropriate application of cobalt, molybdenum, and nickel on seeds enhances growth and symbiotic efficiency. However, excessive doses may cause phytotoxic effects.

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.

Na região semiárida grande parte das espécies florestais apresentam sementes com germinação lenta e desuniforme ao longo do tempo, por possuírem dormência. Diante do exposto, objetivou-se avaliar as características biométricas de frutos e sementes e a influência de tratamentos pré-germinativos na emergência de plântulas de Libidibia ferrea. Foram mensurados o comprimento, largura e espessura dos frutos e o número médio de sementes por fruto. Os dados de biometria foram submetidos à análise descritiva, sendo avaliados a média, máximo, mínimo, desvio padrão, coeficiente de variação e distribuição de frequência. Adotou-se o delineamento inteiramente casualizado, com oito tratamentos pré-germinativos: controle (ausência de tratamento); imersão em ácido clorídrico durante 5, 10, 15 e 20 minutos; imersão em soda cáustica durante 5 e 10 minutos; escarificação mecânica com lixa n° 150 na região oposta ao hilo e posterior imersão em água durante 24 horas. Foram avaliadas as seguintes características: porcentagem, índice de velocidade e tempo médio de emergência, comprimento e massa seca do sistema radicular e da parte aérea das plântulas. O tamanho médio dos frutos foi de 7,93 mm de comprimento, 23,19 mm de largura e 11,87 mm de espessura e 4,67 sementes viáveis por fruto. O uso da escarificação mecânica com lixa n° 150 na região oposta ao hilo com posterior embebição em água por 24 h, é o método mais indicado na superação de dormência de L. ferrea.

The short cultivation cycle and high essential oil content of basil plants render them a valuable raw material source for diverse industries. However, large-scale production is hindered by the lack of specific protocols to assess seed vigor; thus, a consistent supply of high-quality seeds that meet consumer demands cannot be ensured. This study investigated the effectiveness of an automated system for seedling analysis as a tool for evaluating basil seed vigor and compared it to traditional tests. For this purpose, seeds from eight commercial lots were evaluated in two separate trials spaced six months apart using the following tests: germination, first germination count, saturated salt accelerated aging, primary root emergence, mean germination time, seedling emergence, seedling emergence speed index, and computerized seedling image analysis. The parameters provided by the system allowed us to clearly and objectively classify the basil seed lots based on vigor, and the results were strongly and significantly correlated with the findings of traditional vigor tests, particularly between the vigor index and seedling length. Digital analysis of four-day-old seedlings proved to be a fast and efficient technique for evaluating basil seed vigor and has the potential for use in automating the data collection and analysis process.

A Revista Ciência Agronômica é voltada para estudos relacionados com as Ciências Rurais e Recursos Naturais