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The algaroba (Prosopis juliflora (Sw) D.C.) is an exotic species whose leaves have great potential for use in human and animal feeding, being highly nutritious, besides being considered efficient in the recovery of degraded areas and impoverished soils. Despite the growing demand for seeds and seedlings of this species, little is known about the physiological quality of their seeds. Therefore, the objective of this work was to characterize the fruit and seed biometry of the species, as well as to determine the temperatures and substrates for the germination and early development of seedlings. The number of seeds per kilogram and the water content of the seeds were determined. The length, diameter, weight, and number of seeds in each fruit and the thickness, width, length and weight of the seeds were analyzed. In the germination test, three temperatures (20, 30 and 20-30°C) were used under the regime of 14 hours of white light and two substrates (on paper and paper roll). Seed embedding curves, germination, germination speed index, shoot length, root length and seedling dry mass were determined. The biometric data indicate wide variability for the characteristics evaluated for fruits, however, the seeds present less variability. Temperatures of 30 and 20-30 °C and both substrates tested are efficient for conducting the germination test of algaroba seeds in the laboratory.

The main tests that assess the quality of seeds are destructive and require a relatively long time to complete. The analysis of seed images by X-ray is an alternative to this sector, with a reproducible and fast technique, which allows greater flexibility and autonomy to the activities of production systems. The aim of this study was to analyze the internal morphology of Moringa seeds by x-rayed images and to compare it to germination and vigor tests. Four seed lots were used, collected from trees matrixes in Macaíba region, RN state, and subsequently X-rayed and the images were analyzed using ImageJ software after the radiography, submitted to the germination test, first count, germination speed index and length and dry mass of seedlings. The experimental design was completely randomized, with four replicates per lot and the results obtained in this experiment for germination and vigor tests were compared with the free area percentage inside the seed. Lots 1, 2 and 4 had a better result for the germination and vigor tests and lot 3 proved to be of inferior quality. It was observed that the higher the open area inside the seeds was, the lower was the quality of the tested lots of Moringa. The x-rayed image analysis of Moringa seeds with the ImageJ software, allows the measurement of the filled areas and the free areas within the seed as well as the association between these areas and the germination. Severe internal damage, defect and degree of filling detected in X-rays can be associated with poor germination and seedling length reduction.

ABSTRACT The use of new methodological approaches and inclusion of non-destructive evaluations in determining the quality of forest seeds has proven to be of great importance for the development of forest production. The aim of this study was to evaluate the effectiveness of the use of a semi-automated tool for measurement of digital images obtained by the X-ray test in seed lots of Leucaena leucocephala and their relationship to seed physiological quality. Seeds were collected from five mother trees in Viçosa, MG. The study was performed through analysis of radiographic images of the seeds. It was determined the percentage of damaged seeds (predation and fungi) and measured: the area, perimeter, circularity, relative density, and integrated density of the seeds. After the X-ray test, a germination test was performed on the seeds, from which ten variables related to seed physiological quality were extracted, including a vigor index. The use of semi-automated measurement tools associated with the X-ray test was effective for evaluating the internal morphology of Leucaena leucocephala seeds, and the variables determined are related to seed physiological quality.

O objetivo desse trabalho foi adaptar e testar a eficiência da metodologia para teste de condutividade elétrica na avaliação da qualidade de sementes de Moringa oleifera Lam. Para a caracterização fisiológica das sementes, quatro lotes de sementes foram avaliados pelos testes de germinação, emergência de plântula, índice de velocidade de emergência, primeira contagem de emergência, comprimento e massa seca de plântulas e teste de frio. O teste de condutividade elétrica foi avaliado a 25 °C, em 4, 8, 12, 16 e 24 h de imersão em 75 mL e 125 mL de água destilada, utilizando-se 25 e 50 sementes. Empregou-se o delineamento inteiramente casualizado. Os melhores resultados foram obtidos quando utilizou-se 50 sementes imersas em 75 mL ou 125 mL de água destilada por 4 h. O teste de condutividade elétrica adaptado para moringa mostrou-se eficiente em ranquear os lotes de sementes em diferentes níveis de vigor, podendo ser usado com eficiência na avaliação da sua qualidade fisiológica.

O objetivo deste trabalho foi investigar o efeito do substrato, da cor e do tamanho das sementes sobre a germinação e vigor de Melanoxylon brauna. Para tanto foram realizados dois ensaios. No primeiro, as sementes foram classificadas quanto à cor (claras e escuras) e ao tamanho (pequenas e grandes). No segundo ensaio foi investigada a influência dos substratos sobre areia, entre areia, sobre papel, entre papel e rolos de papel, tipo germitest. Em ambos os ensaios, as sementes foram mantidas em condições controladas (luz e temperatura) durante 10 dias. Foi calculado o percentual de germinação e o índice de velocidade de germinação (IVG). Além disso, foi determinado o peso de 1.000 sementes e a germinação da espécie foi caracterizada mediante acompanhamento visual até a formação da plântula. O peso de 1.000 sementes de M. brauna foi de 133,43 g, em média. A protrusão da raiz principal ocorreu em torno de 72 horas após início da embebição, e a germinação observada foi do tipo fanerocotiledonar epígea. Sementes pequenas e claras apresentaram germinação e IVG inferiores às demais. As sementes grandes, independentes da cor, e as pequenas escuras tiveram os maiores IVG e porcentagem de germinação. O substrato mais indicado para a realização de testes de germinação de Melanoxylon brauna foi o rolo de papel.