Deficiências de macronutrientes em sorgo

Abstract

The searching for information about sorghum is increasing and seems to be connected to a greater pontential of productivity, greater resistance to hydro deficit, the forthcoming of new cultivate with good characteristics for the grain production and expansion of its culture in the bushy region. Based on this, the objectives of this work was to verify the typical symptoms and the unique nutritional differences of macronutrients in the sorghum cultivate, by observation of the effects in the omission of nutrients in the development of the plants and this omission effects in the mineral composition of sorghum. The sorghum plants were cultivated in nutritive complete solution of Sarruge (1975), and subordinated to the following elements omissions: N, P, K, Ca, Mg and S. Two days after the start of the research the plants showed already deficiency which was described and characterized. When the symptoms were decisive the plants were collected, washed, separated in leaves, culms, roots, and put to dry, for a posterior determination of dried mass, leave's area and macro and micronutrients values. The visual symptoms of nutrients deficiency were easily seen. The treatments that most affect the dry mass of the different parts of the plants even the leaves were the Nitrogen Calcium and Magnesium omission. The accumulation of nutrients by the plants obeyed the following order: N>K>Ca>Mg>P>S.