Acúmulo de sais no solo, produtividade e teores de íons no milho irrigado com águas salinas de forma contínua ou alternada

• Ano de defesa: 2010
• Autor(a) principal: Moura, Naélia da Silva de
• Tipo de documento: Dissertação
• Tipo de acesso: Acesso aberto
• Idioma: por
• Palavras-chave em Português: Glicine max; Toxidez de alumínio; Estresse oxidativo
• Link de acesso: http://www.repositorio.ufc.br/handle/riufc/36503

The toxicity caused by aluminum in plants grown in soils with low pH is one of the most limiting factors for agricultural production. This study aimed to characterize the stress caused by toxic levels of Al+3 and low pH in different soybean cultivars in relation to general aspects of each genotype exposed to different concentrations and times of exposure to this ion. For that, they moved four experiments in the greenhouse. The first experiment characterized the behavior of one cultivar (M-Soy 8222) submitted to increasing concentrations of aluminum (0, 25, 50, 75 and 100M Al+3). In the second experiment, the differential response of cultivars of soybean, this experiment consisted of two treatments (0 and 100  M Al+3), five cultivars (M-Soy 8222, M-Soy 8866, M9144RR, M-Soy 9350 and FT-106) and three replications. The third experiment examined whether the oxidative stress caused in soybean (M-Soy 8222 and M-Soy 9144) by exposure to low pH and Al+3 in different times and recovery from through the use of an antioxidant. This observation was conducted in five times (0, 12, 24, 48 and 72h) of exposure to treatments of pH (4.0 and 6.0), Al +3 (200M), the antioxidant butyl-hydroxy anisole BHA combined with Al+3 (200  M and 100M) and the antioxidant BHA alone (100M). The fourth experiment was carried out to confirm the results of the third experiment time of 72 hours which was composed of the same treatments as the experiment III. The differential cultivars showed tolerance to the toxic effects of aluminum, but the effects observed only in roots. The cultivar M-Soy 8222, filed an enzyme system of relief more efficient than the cultivar M-Soy 9144, but for parameters on growth and membrane damage, was affected. The use of the antioxidant BHA may reduce the toxic effects of aluminum and also those caused by pH 4.0. The toxic effect caused by Al, observed in this work is similar to those caused by pH 4.0, however we still need more studies on this observation.