Marcha de absorção de macronutrientes e produção de variedades de cana-de-açúcar

Abstract

The increase of the cultivated area with sugarcane in Mato Grosso do Sul has demanded information about the culture, mainly in relation to the nutritional needs of it. There are few studies that report the nutrient uptake in sugarcane, in addition, in the literature there are no reports of studies focused on the production environment of the MS southern region. In view of the above, the objective of this research was to determine the macronutrient uptake and dry matter production in sugarcane varieties. The experiment was carried out in a commercial area of the sugarcane plant Central Energética Vicentina, municipality of Vicentina (MS), during the 2017/2018 harvest, using two varieties of sugarcane (RB92579 and SP832847). The experimental design was in randomized blocks in factorial scheme, with two sugarcane varieties, nine collecting times (90, 120, 150, 180, 210, 240, 270, 300 and 330 days after planting) and 4 replications. Samples were collected from the aerial part of 10 plants, which were divided into leaves, sheaths and stalks, then dried and weighed, and finally the samples were submitted to laboratory analysis to determine the macronutrient contents in each organ. The accumulation of macronutrients in the aerial part of both varieties followed the order: K>N>Ca>S>Mg>P. The export by the stalk followed the order K>N>Ca>S>P>Mg for RB92579 and K>N>Ca=P>S>Mg for SP832847. The maximum accumulation of nutrients and the maximum dry matter production occurred in the interval between 240 and 300 DAP. The variety SP832847 accumulated higher amounts of nutrients and dry matter in relation to RB92579, as well as the time required for the maximum accumulation was shorter.