As sementes de graviola (Annona muricata) apresentam tegumento resistente e impermeável, além de substâncias inibidoras que dificultam a germinação das sementes. Assim, objetivou-se avaliar a contribuição da embebição em ácido giberélico para a superação da dormência e aumento da germinação das sementes de graviola. O delineamento experimental foi inteiramente casualizado, com cinco tratamentos e quatro repetições. As sementes foram escarificadas e em seguida embebidas por 24 horas a 25 ºC em soluções contendo 0; 50; 100; 150 e 200 mg L-1 (ppm) de ácido giberélico. Após este período de embebição as sementes foram submetidas ao teste de germinação, sendo avaliados a porcentagem de germinação, o índice de velocidade e o tempo médio de germinação. As concentrações de ácido giberélico apresentaram efeito sobre a germinação e índice de velocidade de germinação. Conclui-se que a embebição das sementes de graviola na concentração aproximada de 140 ppm de ácido giberélico auxilia na superação da dormência, aumentando a germinação e o índice de velocidade de germinação.

The use of microorganisms is a very recurrent reality in agriculture. Bradyrhizobium japonicum and Azospirillum brasilense benefits the development of plants. There was an increase in the yield components of soybean. Microorganisms are widely used in agriculture. Among them, the bacterial genus Bradyrhizobium is commonly found in cultivated soils, forming symbiotic relationships with legume species. This work aimed to evaluate whether co‐inoculation with Bradyrhizobium japonicum and Azospirillum brasilense influences the components of production, yield, and physiological quality of soybean seeds. The experiment was conducted in three consecutive crop seasons (from 2014–2015 to 2016–2017), in the municipality of Chapadão do Sul, state of Mato Grosso do Sul, Brazil. The experiment consisted of a randomized complete block design, with seven treatments and four replications, using the following treatments: T1, control (without inoculation); T2, inoculation with B. japonicum (150 mL); T3, inoculation with A. brasilense (150 mL); T4, co‐inoculation with B. japonicum + A. brasilense (75 mL + 75 mL); T5, co‐inoculation with B. japonicum + A. brasilense (150 mL + 150 mL); T6, co‐inoculation with B. japonicum + A. brasilense (225 mL+ 225 mL); and T7, co‐inoculation with B. japonicum + A. brasilense (300 mL+ 300 mL). Each treatment (dose) was applied to 50 kg of soybean seeds. The study evaluated the agronomic variables number of nodules per plant, dry shoot biomass per plant, plant height, number of pods per plant, number of seeds per plant, mass of 100 seeds, and grain yield; and the seed quality variables first germination count, germination, emergence, emergence speed index, electric conductivity, accelerated aging, and tetrazolium. The co‐inoculation of soybean seeds with B. japonicum and A. brasilense benefits the development of plants, increasing yield components, grain yield, and seed quality. The most efficient level was 225 mL of each inoculant for 50 kg of seed.

The aim of the present study was to evaluate the effects of temperature, substrate, and luminosity on chia seeds in order to determine adequate conditions for a germination test. The experiment consisted of a completely randomized design, in a 4 × 5 × 2 factorial scheme (four substrates × five temperatures × two luminosity conditions), with four replications. The following variables were analyzed: first germination count, germination, germination speed index, and mean germination time. Germination was best at 15, 20, 25, and 30 °C for the on-paper, paper roll, and sand substrates. However, in the presence of luminosity and at 25 °C, the on-paper substrate had the highest mean. For all substrates, the lowest germination was achieved at 35 °C, proving that high temperatures reduce chia seed germination. Germination speed index was highest at 25 and 30 °C for on-paper, paper roll, and sand substrates, in both the presence and absence of luminosity. Chia seeds are considered to be neutral photoblasts. Germination tests should be performed with the on-paper substrate, at 25 °C, and with a duration of seven days. The first count should be carried out four days after establishment of the test.

Chia (Salvia hispanica L.) is a plant native to central and western Mexico and northern Guatemala belonging to the Lamiaceae family, well known for its seeds containing antioxidants, dietary fibers, and ?-linolenic acid, which helps to prevent different diseases, such as diabetes, obesity, cancer and Alzheimer. In Brazil, there is not much information about the crop, mainly about the physiological quality of its seeds. Therefore, the objective was to establish vigor testing methods to evaluate the physiological quality of chia seeds. Five seed lots were used, in which germination tests, seedling emergence, emergence velocity index and variations in the electrical conductivity test were carried out. The volume of distilled water was 25 and 50 mL, the number of seeds was 50 and 100, the temperature was 20, 25 and 30 °C, the soaking period was 1, 2, 4, 6, 12, 18 and 24 hours and variations in there was accelerated aging test by the traditional method and saturated NaCl solution, being periods of aging as 24, 48, 72 and 96 hours and temperatures of 38, 41 and 44 °C. It is concluded that both the electrical conductivity test and the accelerated aging test are efficient in evaluating the physiological quality of chia seeds. The electrical conductivity test must be performed with 100 seeds in 50 mL of distilled water, for four hours soaking at 25 or 30 °C; and the accelerated aging test should be performed at 44 °C for 24 hours by the traditional method or 41 °C for 24 hours using saturated NaCl solution.

The present study aimed to assess the variations in the parameters of the exudate pH and flooding tests to evaluate the physiological quality of soybean seeds. We subjected the lots of soybean seeds to germination, emergence, exudate pH, and flooding tests. Further, water content of the seeds, first count of germination, and emergence speed index were also determined. The exudate pH test studied the variations in the soaking period and temperature, while the flooding test assessed the variations in the amount of water and temperature at different periods of immersion. The experiment design was completely randomized. The results were presented as means and were compared using the Scott-Knott test at 5% probability. The Pearson’s correlation coefficient between the exudate pH and emergence of seedlings, and also between the flooding test result and emergence of seedlings were calculated. The results of the study indicated that the exudate pH test can be used to evaluate the physiological quality of soybean seeds after 30 min of imbibition at 20 °C. Further, the flooding test was efficient in evaluating the vigor of soybean seeds after 4 h of immersion either in 50 mL of distilled water at 25 °C or in 75 mL of distilled water at 30 °C.

This study aimed to evaluate the effects of chemical treatment of seeds with fungicide and insecticide on the seed physiological quality of Brachiaria brizantha cultivar MG5. Two experiments with four replicates were carried out in a completely randomized design. In the first experiment, the seeds were treated with the fungicide pyraclostrobin + fipronil + thiophanate-methyl and in the second, with the insecticide thiamethoxam, both at doses of 0, 150, 300, 450, and 600 mL of commercial product (CP)/100 kg of seeds. Physiological characterization was done on the basis of the first germination count, germination (%), emergence (%), emergence speed index, and length and dry mass of shoot and root. The treatment of B. brizantha seeds with the fungicide pyraclostrobin + fipronil + thiophanate-methyl benefits the physiological quality of seeds, improving germination and root development, with no phytotoxic effect up to the dose of 600 mL of CP/100 kg of seeds. The insecticide thiamethoxam has a biostimulating effect on B. brizantha cultivar MG5 up to the dose of 270 mL of CP/100 kg of seeds, but is phytotoxic in larger doses.

The root protrusion test is a vigor test based on the principle that seeds with high vigor emit the primary root faster than less vigorous ones. Chia is a plant propagated by seeds and it is studied owing to its health benefits, but there is little technical information known about its culture. The objective of this work was to adapt the methodology of the root protrusion test to determine the vigor of chia seed lots. Five chia seed lots were submitted to an initial quality evaluation using germination and vigor tests (first germination, emergence, and emergence speed index). The root protrusion test was performed at temperatures of 20, 25 and 30 °C and evaluated every 2 h up to 42 h. During the test, protrusion stability was assessed and the criterion of 2 mm primary root count was used. The root protrusion test at 20 °C did not distinguish the lots in the same way as emergence. At 25 °C it was possible to classify lots after 30 h similarly to emergence. At 30 °C, root protrusion and the separation of seed lots was accelerated. Thus, the root protrusion test conducted for 30 h at 25 °C has sufficient sensitivity to detect differences in vigor between chia seed lots.

In general, seeds are not used immediately after harvesting. For this reason, they have to be stored for future use, which requires the maintenance of their viability during the storage time by applying the appropriate conservation technology for each species. This study aimed to evaluate whether package and environmental conditions interfere with the physiological quality of chia seeds (Salvia hispanica L.) stored for 12 months. The experiment consisted of a completely randomized design in a 3 × 3 × 4 factorial scheme, with four replications, using three packages, three storage environments, and four storage times. After each storage time, seeds were subject to germination and vigor tests (emergence and electrical conductivity). Chia seeds can be stored in a cold or dry chamber, in plastic, glass, or paper containers, for 12 months, without hindering seeds physiological quality.