Growth and nutrient accumulation in elephant grass crop

Crescimento e acúmulo de nutrientes na cultura do capim-elefante

ABSTRACT

Elephant grass fertilization is performed more efficiently by analyzing growth curves and nutrient accumulation. This study evaluated elephant grass's growth, dry matter production, and nutrient accumulation. A sampling design was used, with plant collections over time. Elephant grass was cultivated in four plots of 27 m² during two cultivation cycles. Destructive sampling of four plants was carried out per collection to evaluate dry matter production and nutrient accumulations. In the first cycle, plants were collected at 21, 35, 49, 63, 77, 91, 105 and 119 days after planting. After the last collection of the first cycle, a standardization cut was made, eliminating the remaining plants in the experimental plots. The second cycle of collections was carried out at 21, 35, 49, 63, 77, 91, and 105 days after the uniformity cut. In all collections, the number of tillers per linear meter was counted, and the height of the plants was evaluated. The data were subjected to nonlinear regression analysis. The accumulation of nutrients by elephant grass accompanied the production of dry matter. The highest rates of dry matter production occurred around 70 days. The greatest height growth occurred from 18 to 102 days in the 1st cycle and 8 to 61 days in the 2nd cycle. Nutrient accumulation showed the following decreasing order: K>N>Mg>Ca>P>S>Fe>Mn>Zn>Cu (1st cycle); and K>N>Mg>Ca>P>S>Fe>Zn>Mn>Cu (2nd cycle).

Keywords:
Pennisetum purpureum ; Fertilization; Macronutrients; Micronutrients