Descripción: |
Phosphorus (P) and zinc (Zn) availabilities are important to the nutrition of tropical forage grasses. In this manner, this study aimed to identify and quantify changes in metabolism, tillering, and root system of Brachiaria brizanthacv. ?Marandu? related to P and Zn availabilities. Plants of B. brizanthacv. ?Marandu? were grown in nutrient solution under five rates of P (0.1, 0.6, 1.1, 1.6, and 2.1 mmol L−1) and five rates of Zn (0.00, 0.75, 1.5, 2.25, and 3.00μmol L −1 ), in a fractionated factorial. The interaction Px Zn rates and the Zn supply were not significant for the activity of acid phosphatase enzyme, P-use index, number of tillers, and root parameters. P-use index and enzyme activity decreased as P availability increased. The high efficiency in P use was a result of high acid phosphatase activity and P supply was essential to the development of ?Marandu? palisadegrass root system. 2014 |