Resposta do sistema antioxidativo sob a influência de 6-benzilaminopurina na micropropagação de cana-de-açúcar

Abstract

The occurrence of supersprouting in sugar cane, known as "green masses", was evaluated for the effect of BAP, correlating with the response of antioxidative system of plants and green masses. The plant material was derived from micropropagation in temporary immersion bioreactors (BIT) with BAP. Plants and green bodies were transferred to culture in static system in a liquid medium with or without BAP. Micropropagated plants in BIT without BAP remained without cytokinin, in static fluid system. Plants that remained with BAP (PcBAP) had increased tillering, but there was an inverse relationship to the size of the tiller. The presence of BAP inhibited the rooting of shoots and masses. In treatments with BAP in static system continued with the formation of green mass, proving that the culture system did not affect the occurrence of the anomaly, which was conditioned by prolonged exposure to BAP. The highest activity of POD was observed in roots and shoots of plants were in cultivation without BAP and had higher root formation, confirming the role of POD in the metabolism of indole acetic acid (IAA). The activity of catalase and ascorbate peroxidase were somewhat complementary, highlighting the need of joint antioxidant enzyme system. The activity of polyphenol oxidase in roots was higher in plants without BAP. In the green masses PPO activity was inversely proportional to total phenols. The phenolic content increased in shoots of plants grown with BAP and BAP in the masses without green (and PsBAP MsBAP), which coincides with rooting. There was no difference in total glutathione, but the plants that were not subject to the presence of BAP exhibited the highest ratio reduced glutathione / glutathione disulfide (GSH / GSSG).