In recent research, early stages of coffee seedling development were identified, after radicle protrusion, in which all the essential parts of the seedling can be assessed to demonstrate the potential of seed germination to generate normal plants. Thus, the objective of this research was to develop studies to reduce the time on the germination test. Ten seed lots of coffee were assessed through the germination test, every two days, from the tenth day of sowing, according to the morphological criteria of the seedlings. The data were compared to the standard germination test and analyzed by means of regression analysis and segmented nonlinear regression and planteau response model. It was concluded that the assessment of coffee seedlings at 16 days, in stage S1, provides the similar result of the pattern germination test, allowing a significant reduction of time in order to demonstrate the germination of the seed lots; the seedling assessment coffee in stage S2 does not have reduction of the time for assessing the coffee germination, in relation to the pattern.

Fungi are considered as the most important among pathogens due to the higher number of species and to the damage caused both in yield and in seed quality. Thus, aimed to verify the effect of fungicide and insecticide treatment on sanitary quality and physiological performance of soybean seeds before and after storage. Seeds from cultivars NS 7494, NS 8693 and NS 7338 IPRO were used, which were analyzed separately by a completely randomized design in a 3 x 6 factorial design, being three chemical treatment applications: 1) treated and evaluated; 2) treated, stored and evaluated; 3) stored, treated and evaluated; and six mixtures of fungicides and insecticides: (Imidacloprido + Tiocarbe) + (Carbendazim + Tiram), (Imidacloprido + Tiocarbe) + (Metalaxil-M + Fludioxonil), Thiamethoxam + (Carbendazim + Tiram), Thiamethoxam + (Metalaxil-M + Fludioxonil), (Fipronil + Piraclostrobina + Metil-tiofanato) and the control, which was added only water. The healthy test, germination, cold and accelerated aging tests were evaluated. Seed treatment products require at least two months to be effective in controlling Penicillium spp. and Fusarium spp. The mixtures containing Carbendazim + Tiram in its composition are efficient in the control of pathogens regardless of the application time of products.

-Given what is already known in regard to seed health and the availability of molecular methods for detection of the pathogens Stenocarpella maydis and Stenocarpella macrospora in maize seeds, Colletotrichum gossypii var. cephalosporioides in cotton seeds, and Corynespora cassiicola in soybean seeds, the aim of this study was to evaluate seed vigor according to different inoculum potentials. The fungus isolates were inoculated on seeds by the technique of water restriction, through which different inoculum potentials are obtained, corresponding to times of seed exposure of 0, 24, 48, and 96 hours for maize and cotton seeds, and 0, 36, 108, and 144 hours for soybean seeds. The seeds were subjected to germination, electrical conductivity, health, and qPCR tests. Results of the blotter test showed that in most pathosystems, there was a higher incidence of the fungi with an increase in inoculum potential. A decrease in germination percentage was observed in all species as inoculum potential increased, as well as further degradation of seed membranes. The qPCR test confirmed that the most damaged seeds in the tests had higher presence of the pathogens.Index terms: seed pathology, fungi, maize, soybean, cotton.Avaliação do potencial de inóculo de patógenos em sementes: sua relação com a qualidade fisiológica e quantificação do DNA por qPCR RESUMO -Diante do que já se conhece em sanidade de sementes e tendo-se em mãos métodos moleculares para a detecção dos fungos Stenocarpella maydis, Stenocarpella macrospora em sementes de milho, Colletotrichum gossypii var. cephalosporioides em algodão e Corynespora cassiicola em soja, objetivou-se neste estudo avaliar o vigor das sementes em função dos diferentes potenciais de inóculo. Os isolados dos fungos foram inoculados nas sementes por meio da técnica de restrição hídrica pela qual se obtém diferentes potenciais de inóculo, que foram representados por P0, P24, P48 e P96 e P0, P36, P108 e P144, que correspondem à exposição das sementes aos períodos de tempo de 0, 24, 48, 96 horas (milho e algodão) e nos tempos 0, 36, 108 e 144 horas (soja), respectivamente. As sementes foram submetidas aos testes de germinação, condutividade elétrica, sanidade e qPCR. Pelo blotter test, na maioria dos patossistemas, houve maior incidência do fungo com o aumento do potencial de inóculo. Foi observada uma queda na porcentagem de germinação de todas as espécies com o aumento do potencial de inóculo, assim como maior degradação das membranas das sementes. A qPCR confirmou que nas sementes mais prejudicadas havia maior quantidade de inóculo dos patógenos.Termos para indexação: patologia de sementes, fungos, milho, soja, algodão.

Amaranthus species have great potential for human food due to their nutritional and functional properties, but there are few phytotechnical studies with this crop, making its cultivation unfeasible. Aiming to encourage the production of these species, this study aimed to evaluate and distinguish the morphological, chemical and physiological characteristics of seeds of Amaranthus sp. (commercial species), A. viridis and A. hybridus. The experiments were performed in a completely randomized design, evaluating seeds in size classes (850, 600 and 425 µm) and characterizing them by image analysis using the GroundEye® system, near-infrared spectroscopy (NIR) and radiographic analysis. The first germination count, germination and germination speed index with and without KNO3 were performed to evaluate the physiological quality of seeds. The results were submitted to analysis of variance and the means compared by the Tukey test. Radiographic analysis showed that the seeds of the three studied species were filled in the size class of 600 and 850 µm, without dormancy, but the commercial species had higher germination speed. GroundEye® and NIR allowed distinguishing the three species according to their geometric characteristics, predominance of color and chemical components.

This study aimed to evaluate the near-infrared spectroscopy potential in analyzing the quality of cottonseed regarding different physiological quality levels, noting the need for faster techniques and tools to aid decision making. It was used eight samples of cottonseed with and without lint, presenting different physiological quality. The “high” (lots 1, 4, 5, 6 and 7) and “low” (lots 2, 3 and 8) vigor levels were defined based on vigor tests carried out and on the Normative Instruction 45/2013. The near infrared spectroscopy spectra was obtained from four types of sample preparations: whole seeds, cut in a half, without tegument and grounded seeds. Using the spectra and the grouping of lots in high and low vigor, cross validation models were optimized, built using the PLS - DA method, making it possible to predict seed classes. Grounded seeds were the best type of sample preparation, with 95% of correct predictions for high vigor seeds and 100% of low vigor (both for seeds with lint) and with 100% correct predictions for high vigor seeds and 91.7% low vigor (without lint).