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The differentiation of seedling growth and development is the result of the vigor level of the seed lot. Because of this, knowing the seedling growth curve is essential for the evaluation of the seedling length test, to be carried out at the moment when any differences in vigor really manifest, thus being able to reduce the time of evaluation of the test. In this research, the objective was to determine the most efficient time interval to perform the seedling length test in soybean seeds, depending on the vigor levels. The evaluated characteristics were percentage of seed germination, first germination count, emergency, days for emergence, aerial, root and total length (evaluated every 12 hours), aerial, root and total dry mass in completely randomized design. High vigor seeds originated seedlings with higher growth rates (cm. h-1), with vigor being one of the factors that interfere in the seedling length test. After 96 hours of the seedling length test, there was a statistical differentiation between the three vigor levels tested. The soybean seedling length test between lots, with different vigor, can be performed 96 hours after sowing. RESUMO: A diferenciação do crescimento e desenvolvimento das plântulas, é resultado do nível de vigor do lote das sementes. Em virtude disto, conhecer a curva de crescimento das plântulas é fundamental para que a avaliação do teste de comprimento de plântulas, seja realizada no momento em que realmente se manifestem as eventuais diferenças de vigor, podendo assim reduzir o tempo de avaliação do teste. No trabalho, o objetivo foi determinar o intervalo de tempo mais eficiente para realizar o teste de comprimento de plântula em sementes de soja, em função dos níveis de vigor. As características avaliadas foram germinação, primeira contagem de germinação, emergência, dias para emergência, comprimento de parte aérea, raiz e total (avaliados de 12 em 12 horas), massa seca de parte aérea, raiz e total em delineamento inteiramente casualizado. As sementes de alto vigor originaram plântulas com maiores taxas de crescimento (cm. h-1), sendo o vigor um dos fatores que interfere no teste de comprimento de plântulas. Após 96 horas do teste de comprimento de plântula ocorreu a diferenciação estatística entre os três níveis de vigor testados. O teste de comprimento de plântula de soja entre lotes, com vigor distinto, pode ser realizado 96 horas após a semeadura.

Storage is a fundamental step for maintaining seed quality after processing. Thus, in this study, we evaluated the physiological potential of onion seeds stored in different packings and environments. Impermeable, semi-permeable and permeable packings were tested under natural environment conditions (+19ºC), cold and dry chamber (10±2ºC and 33% RH) and cold chamber (16±2ºC and 60% RH), at 0, 90, 180, 270 and 360 days. The design was completely randomized in a 3x3x5 factorial scheme, with three replicates. In order to evaluate emergency in field, a 3x3 factorial arrangement (packing x environment) was adopted. Onion seeds maintained their physiological quality when stored in impermeable packing for 360 days, regardless of the environment. The seeds' physiological quality was maintained in the other packings when stored in a cold or cold and dry chamber, with viability and vigor above 80% up to 180 days of storage.

The aim of this research was to study the linear correlations and spatial distribution between soil attributes and productivity and physiological quality of wheat seeds. Soil samples were collected at georeferenced points in an area of 41 ha with a rectangular grid of 100 × 100 m to determine soil fertility. Grain productivity, number of ears m-2, protein content, and physiological seed quality were assessed. The results were submitted to Pearson's correlation analysis, descriptive statistics, and geostatistics. Phosphorus content presented a high spatial variability, with a coefficient of variation of 97.79%. Protein content, number of ears, and SMP index presented low values of coefficient of variation, indicating their low spatial variability. Physiological seed quality was not correlated with soil attributes. Wheat productivity showed a strong correlation between calcium and soil organic matter contents, as verified by analyzing the spatial distribution maps. The analysis of the spatial distribution maps of soil nutrients is a tool that can contribute to farmers’ decision making in the management of crop fertilization aiming at increasing productivity.

The objective of this work was to evaluate the effect of different doses of phosphorus in the growth and development of amaranth plants and in the physiological quality of the seeds produced, as well as to identify the interrelationships between the morphological and physiological attributes. The experiment was carried out in the agricultural crop 2016/2017 in Federal University of Pelotas. Made available in DSpace on 2019-12-09T18:14:40Z (GMT). No. of bitstreams: 1 Phosphatefertilizationandinterrelationshipsoftheagronomicandphysiologicalcharactersofamaranthseeds.pdf: 527690 bytes, checksum: 9d9989d145fb1e9b2985eceb437fc5a5 (MD5) Previous issue date: 2019