Identification of mineral deficiencies through the diagnosis by subtraction in a soil of the northwest of Paraná cultivated with Mombaça grass

Abstract

An experiment was carried out under greenhouse conditions at the Agronomy Department of the State University of Maringá (UEM), using the techniques of diagnosis through subtraction. Mineral nutrition in macro and micronutrients for Mombaça grass, cultivated in a soil originated from Caiuá sandstone was analyzed. The soil was collected in a 0-20 cm layer in the northwest of the state of Paraná, Brazil. A cut in the aerial part of plants at 59 days after Mombaça grass planting was performed and the obtained weight of dry matter was determined: weight of leaf fresh dry matter (PMSFF), weight of stem fresh dry matter (PMSFC), weight of root fresh dry matter (PMSFR), weight of aerial parts fresh dry matter (PMSPA) and leaf/thatch (F/C) rate. The number of affiliates (NP) was determined. The results showed that the soil was unable to furnish the nutritional requirements of Mombaça grass in N, P, K and micro, and it was able in terms of S. These data indicate the need of other experiments that may determine the amount and the better source of any nutrient that will stimulate a positive response to Mombaça grass