Estresse oxidativo em raízes de plantas jovens de cana-de-açúcar sob toxidez de alumínio e com suplementação de silício.

• Autor(a) principal: Palma, Milena Silva Garcia
• Data de Publicação: 2021
• Tipo de documento: Trabalho de conclusão de curso
• Idioma: por
• Título da fonte: Repositório Institucional da UNESP
• Texto Completo: http://hdl.handle.net/11449/213513
• topic: Ecofisiologia Vegetal; Saccharum officinarum; Estresse abiótico; Crescimento (Plantas)

In recent years, the cultivation of sugarcane is being directed to the Cerrado, a region characterized by acidic soils in which aluminum (Al) toxicity it's present. Because of the low mobility of Al in plant, the toxicity reaches the roots, causing drastic reduction in growth, thickening and a decrease in the permeability of the cells, which restricts the absorption of water and nutrients. Aiming to alleviate the toxic effects of Al, the studies have highlighted the benefits of applying silicon (Si), which is shown to attenuator the most varied stresses in plants. The aim of this work was to verify the attenuating effect of Si on roots of young sugarcane plants under Al toxicity. Sugarcane seedlings, cv. CTC9003 with 40 days of age, were submitted to Al toxicity (0, 10, 15 e 20mg L-1 of Al2(SO4)3.18H2O) for 15 days and Si treatments (0,0 e 2,0 mmol L-1 of K2SiO3) for another 20 days in nutrient solution. Oxidative metabolism was evaluated through determining lipid peroxidation (malondialdehyde, MDA) and antioxidant defense system by enzymes superoxide dismutase (SOD), ascorbate peroxidase (APX) and guaiacol peroxidase (GPOX). The growth of the roots was verified by the evaluation of dry biomass. The results evidenced that in Al stressed plants, the Si supplementation reduced MDA and increased the antioxidant activity of SOD, APX and GPOX, which may have contributed for the greater root growth than in the plants under Al and without Si. The Si attenuated Al stress in the roots of young sugarcane plants, cv. CTC9003.