Urochloa Cultivated in Soil with Aluminium: A Development and Stomatal Approach

Some Brazilian soils present low fertility, acidity and also toxicity caused by the presence of aluminium, leading to a lower development of forages. In view of the above, this work aimed to know Urochloa cultivated in soil with aluminium: a development and stomatal approach. The experimental design was a factorial of 3x5, with three cultivars of Urochloa brizantha: Marandu; Paiaguás and Piatã, and five concentrations of aluminium in the soil: 2.0; 4.0; 8.0; 16.0 and 32.0 mmol dm-3 of Al, with four replications, a total of 60 plots. Sixty days after the harvest the following parameters were set: number of leaves (NF); plant height (PH); dry mass of the aerial part (DMAP). The lower or abaxial epidermal impression of the fragments collected using cyanoacrylate ester was used to determine: Stomata Density (SD) and stomatal functionality (SF). The presence of aluminium in the soil negatively influenced the development of plants. All Urochloa cultivars presented similar responses as exposed to different doses of aluminium in the soil. Doses above 2.0 mmol of aluminium in the soil harmed the development of U. brizantha. The cultivar Marandu presented the highest number of leaves and presented better development.