Improving the method for determining the physiological and sanitary potential of Gherkin seeds

Gherkin seeds usually show irregular physiological quality. Seed production requires fast and reliable tests to evaluate seed quality. Germination test is considered a recognized analysis method; however, seed technology has pursuit the improvement of vigor tests aiming the evaluation of seed's physiological potential. Thus, the objective of this work was to evaluate procedures to perform the test of accelerated aging and determine the physiological and sanitary potential of gherkin seeds. Four seed lots of cultivar Liso Calcuta were used in the study. To evaluate the initial physiological quality the water content was determined and germination and emergence tests, as well as indices of germination speed and emergence speed were used. The accelerated aging test was performed as traditionally and with saturated saline solution, with 48, 72 and 96 hours, at temperatures of 41oC and 45oC. After aging, the water content was determined, and seeds' germination and sanity tests were performed. The experiment was set under a completely random design in factorial 4x3x2 (lots x aging periods x temperatures). The standard accelerated aging test and the test with saturated saline solution at 41oC for 96 hours were efficient to evaluate the vigor of gherkin seeds. Saturated saline solution provides uniform water absorption and deterioration in gherkin seeds, allowing to discriminate seed lots in different vigor levels. The salinity test after accelerated aging with saline solution reduces the incidence of some fungi.

Seed conditioning process in the sanitary quality of marandu grass seeds / Processo de condicionamento de sementes na qualidade sanitária de sementes de capim-marandu

The purpose of seed conditioning process is to separate seeds and their associated structures into different fractions and retain only good and healthy seeds. Thus, the aim of this study was to evaluate the effects the stages of seed conditioning have on the sanitary quality of marandu grass seeds. The seeds were sampled before and during the seed conditioning process, i.e., after exiting the air-screen cleaner and sieves (seeds discharged from the top, middle and bottom sieves), the first gravity separator (seeds drifting around the table, upper and intermediate discharge) and second gravity separator (upper, intermediate and lower discharge). The sanitary analysis was performed using the filter paper method with and without surface disinfestation of the seeds, which were incubated at 20±2°C, with a photoperiod of 12 hours for seven days. The experiment was conducted in a completely randomized design, in a 2x6 factorial scheme (surface disinfestation x stages of the seed conditioning process) and ten replications. The data was submitted to analysis of variance, using the F test and, when significant, the means of the treatments were compared using the Tukey test at 5% probability. It was concluded that it is not possible to improve the sanitary quality of marandú grass seeds through the seed conditioning process.

A finalidade do beneficiamento de sementes é separar as sementes e suas estruturas associadas em diferentes frações e reter apenas sementes boas e saudáveis. O objetivo deste trabalho foi avaliar o efeito das etapas do beneficiamento sobre a qualidade sanitária de sementes de capim-marandú. As sementes foram amostradas antes e durante o beneficiamento: após a saída da máquina de ar e peneiras (descarga das peneiras superior, intermediária e fundo), primeira mesa gravitacional (deriva ao redor da mesa, descarga superior e intermediária) e segunda mesa gravitacional (descarga superior, intermediária e inferior). A análise sanitária foi realizada pelo método do papel de filtro com e sem desinfestação superficial das sementes, as quais foram incubadas a 20 ± 2 °C, com fotoperíodo de 12 h durante sete dias. O experimento foi conduzido em delineamento inteiramente casualizado, em esquema fatorial 2x6 (desinfestação superficial x etapas do beneficiamento) e dez repetições. Os dados foram submetidos à análise de variância pelo teste F e quando significativa, as médias dos tratamentos comparadas pelo teste de Tukey, a 5% de probabilidade. Foi possível concluir que o beneficiamento não é capaz de melhorar a qualidade sanitária das sementes de capim-marandú.