SUMMARY:This study aimed to evaluating salt stress effects on germination of BRS-122 sunflower seeds, through determination of reserve mobilization by cytochemical and biochemical methods. The experiment consisted in the seed germination in control treatment (distilled water) and salt treatment (200 mM NaCl) in germination chamber (BOD) at 25 °C and 12h photoperiod of light. In lipid determination, there was an accumulation of these reserves in cotyledons, in salt conditions, demonstrating a delay in the use of these reserves. Regarding to protein mobilization, a 21.2% reduction was observed for these contents in control treatment at 2DAI, and on other hand, at the final germination period, it was verified an accumulation of proteins. The Na + content was higher in plants exposed to NaCl, whereas K + content was reduced over time in control treatment, however, in salt conditions, there was an accumulation of this ion. We assumed that the salinity exposure in sunflower seeds led to Na + ion accumulation, which negatively affected the reserve mobilization of these seeds.
KEYWORDS: Germination, Helianthus annus L., salinity
MOBILIZAÇÃO DE RESERVAS DE SEMENTES DE GIRASSOL SUBMETIDAS AO ESTRESSE SALINORESUMO: Nesse trabalho, objetivou-se estudar os efeitos do estresse salino sobre a germinação de sementes de girassol BRS-122, avaliando a mobilização de reservas ao longo da germinação por meio da determinação de compostos de reserva por métodos citoquímicos e bioquímicos. O experimento consistiu na germinação das sementes em tratamento controle (água destilada) e tratamento salino (200 mM de NaCl) em câmara de germinação (BOD) com temperatura de 25°C e fotoperíodo de 12h. Na determinação de lipídios, observou-se que no tratamento salino houve um acúmulo de lipídios nos cotilédones, demonstrando retardo na utilização dessas reservas. Em relação a mobilização proteica dos cotilédones para o eixo