Testes para análise de vigor em sementes de girassol

Abstract

Research with the sunflower crop currently emphasize the use for oil extraction for biodiesel production. The sunflower, because it is a culture of broad adaptation and soil nutrient cycling, has been deployed in systems of crop rotation. An important strategy for the success of any crop seed is the use of good quality in order to obtain suitable plant stand. But often lacking appropriate tests to determine the quality of seeds, making the choice of the best lots. In this sense, the objective is to determine the appropriate methodology for analysis of the effect of sunflower seeds, through electrical conductivity mass and individual test and pH exudates, as well as determining the number of samples in the number of seeds for evaluation of Individual electrical conductivity of sunflower seeds. Experiments were conducted, which evaluated the mass electrical conductivity, electrical conductivity and pH of the individual exudate and established the relationship of these tests with the test field emergence. The electrical conductivity mass and individual are promising in the separation of lots of sunflower seeds, and the best conditions for performing the electrical conductivity test mass is 25 seeds, 25 ml of water and reading done after an hour of soaking. For the electrical conductivity test individual periods 1 - 24 hours have high correlation between field emergence and electrical conductivity individual. The sample size seed number, to evaluate the conductivity of sunflower seed, is dependent on the time of seed imbibition. Soaking times an hour using the smallest possible sample sizes. Considering the range of 15 μS cm-1 seed-1 is recommended sample size of 100 seeds.