Morphological and Productive Evaluation of Mombasa Grass as a Function of Phosphate, Nitrogen and Biostimulant Application

Abstract

Nitrogen when applied to the surface, suffers losses by volatilization. Therefore, one of the ways to reduce this loss is to use substances that delay the hydrolysis of NH3. The objective of this study was to evaluate the physiological characteristics of Mombasa grass as a function of nitrogen sources associated or not with volatilization inhibitors (ASP4) and nitrification (CTN). The experiment was conducted in a greenhouse, UFT - Gurupi, in DBC, with six treatments and five replications, being: SN1 - Sulfammo without ASP4; SN3 - Sulfammo + 6kg/ton of ASP4; NC1 - Sulfammo + CTN without ASP4; NC3 - Sulfammo + CTN + 6kg/ton of ASP4, URE - Urea and control without nitrogen. It is note point that all treatments received 100 kg ha-1 of N. The following parameters were evaluated: Chlorophyll A, Chlorophyll B, Total Chlorophyll, internal CO2 concentration, transpiration rate, stomatic conductance, CO2 assimilation rates, water use efficiency, and instantaneous efficiency of ribulose enzyme (RUBI) carboxylation Data were analyzed by MANOVA, using the main component technique (PCA) using the R® 3.5 software. According to the PCA scores, the productive characteristics are CloB; CloA; CloTO. ASSI, RUBI showed the highest variations, all positive, both in PC1 and PC2. The treatments that most influenced the characteristics were NC1 and NC3, demonstrating an inverse tendency to the controls. Crop development was significantly influenced by urea and sources with and without inhibitors.