Agricultural species are subjected to a variety of biotic and abiotic stresses, which are the main limitations to crop production. In this context, contamination by trace elements is characterized as an abiotic stress that represents an environmental problem. Due to the physical and chemical similarities between cadmium and zinc, these elements may interact in the environment and may cause antagonistic or synergistic effects. In this way, physiological mechanisms to exclude, detoxify or compartmentalize trace elements that are in excess are crucial for plant survival when exposed to high concentrations of these elements. In this way, the aim of this study was to understand the physiological responses of Phaseolus vulgaris plants subjected to increasing doses of Cd and Zn for 21 days in different soil, Cambisol and Latosol. The activity of antioxidant enzymes, such as SOD, CAT, and APX; hydrogen peroxide content; lipid peroxidation; chlorophyll index; photosynthetic rate; stomatal conductance; and transpiration were analysed. The data obtained showed a specific behaviour of Phaseolus vulgaris plants in each soil analysed. Moreover, it was observed that interactions between both elements resulted in a synergistic effect, negatively affecting all of the parameters analysed.

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-Contamination with trace elements is characterized by an abiotic stress that represents a limiting factor in agricultural production. Considering that cadmium (Cd) and Zinc (Zn) are physically and chemically similar, they can interact with the environment, causing antagonistic or synergistic effects. In this sense, physiological mechanisms to exclude, detoxify or compartmentalize the excess of those trace elements is crucial for the survival of the plants under conditions of high concentrations of these elements. In order to understand the responses of the species sensible to the presence of Cd and Zn, this study aimed to access the behavior of maize plants (Zea mays L.) cultivated in Cambisoils and Latosol with growing concentrations of Cd/Zn in a 21 days period. Growth and biochemical analyzes were performed such as antioxidant enzyme SOD, CAT and APX activity, hydrogen peroxide and lipid peroxidation. The data obtained evidenced the specific behavior of maize plants grown in Cambisoils compared to Latosol, showing a superior activity of all the enzymes analyzed, and also a lower content of hydrogen peroxide and lipid peroxidation. The interaction between both the elements resulted in a synergistic effect, negatively influencing all the analyzed parameters. Keywords: trace elements, antioxidant enzymes, ROS, synergistic. CRESCIMENTO E RESPOSTAS BIOQUÍMICAS DE PLANTAS DE MILHO CULTIVADAS EM SOLOS MULTICONTAMINADOS COM CÁDMIO E ZINCORESUMO -A contaminação por elementos traço caracteriza-se como um estresse abiótico que representa um fator limitante para a produção agrícola. Em função das semelhanças físicas e químicas entre cádmio (Cd) e zinco (Zn), esses elementos podem interagir no ambiente, podendo causar efeitos antagônicos ou sinérgicos. Nesse sentido, mecanismos fisiológicos para excluir, desintoxicar ou compartimentalizar o excesso de elementos traço são cruciais para sobrevivência dos vegetais quando expostos a elevadas concentrações desses elementos. A fim de compreender melhor as respostas de espécies sensíveis à presença de Cd e Zn, o presente estudo teve como objetivo avaliar o comportamento de plantas de milho (Zea mays L.) cultivadas em Cambissolo e Latossolo contendo concentrações crescentes de Cd/Zn. As plantas foram expostas a doses crescentes de Cd/Zn, por um período de 21 dias. Foram realizadas análises de crescimento e análises bioquímicas tais como, atividade das enzimas antioxidantes SOD, CAT, APX, assim como a quantificação do peróxido de hidrogênio e peroxidação lipídica. Os dados obtidos evidenciaram comportamento específico das plantas de milho cultivadas em Cambissolo, quando comparado ao Latossolo, apresentando uma atividade superior, em todas as enzimas analisadas, e um menor conteúdo de peróxido de hidrogênio e peroxidação lipídica. Observou-se que a interação entre ambos os elementos resultou em um efeito sinérgico, afetando negativamente todos os parâmetros analisados. Palavras-chave: elementos-traço, enzimas antioxidantes, EROs, sinergismo.