Efeitos fisiológicos da aplicação de Níquel e Silício na cultura da soja

Abstract

ABSTRACT: Nickel (Ni) influences a variety of physiological processes in plants, which can promote an increase in growth and production. Silicon (Si) improves the photosynthetic rate, efficiency in water use, in addition to helping in the osmotic regulation and antioxidant system of plants. This study aimed to evaluate the physiological effects of foliar application of Ni and Si, isolated and associated, on soybean plants. The experiment was conducted in the field at the Federal University of Mato Grosso do Sul, Campus Chapadão do Sul in the 2022-2023 harvest. The experimental design was randomized blocks, with four treatments: T1 – application of Ni, T2 – application of Si, T3 – application of Ni + Si, T4 – no application, arranged with 6 replications. The physiological variables evaluated were: total chlorophyll, carotenoids, flavonoids, photosynthesis, internal CO2 concentration (Ci), transpiration (E), stomatal conductance, water use efficiency (WUE), and instantaneous carboxylation efficiency. In addition to the analysis of grain productivity. According to the treatments, when the combination of Ni + Si was applied, the variables photosynthetic pigments and gas exchange (chlorophyll, carotenoids, flavonoids, photosynthesis, stomatal conductance, carboxylation efficiency) obtained higher levels and better efficiency for soybean plants. , but did not differ from the Si and Ni treatments alone. For the variable Ci there was no difference between treatments; in relation to E, the best treatments were Si and Ni alone and; for WUE the best treatment was Si. Soybean productivity did not increase in response to the application of treatments. Thus, the foliar application of Ni and Si, combined or isolated, promotes improvements in pigment levels and gas exchange in soybean plants; however, for productivity there was no effect from the application of these elements.