Yield components and morphogenesis of Aruana grass in response to nitrogen supply

Areas with Aruana grass (Panicum maximum Jacq.) in Brazilian pastures, especially those used by sheep, have expanded due to yield and morphological characteristics of this grass that are favorable to these animals. Nevertheless, the knowledge concerning yield attributes of this grass in relation to nitrogen fertilization is very limited. The objective of this research was to evaluate yield and physiological attributes in this forage grass when grown in nutrient solutions containing N rates. The experiment was carried out in a greenhouse with plastic pots containing ground quartz as substrate, during the Spring season. Six N rates in the solution (14, 112, 210, 294, 378, and 462 mg L-1), with 70% N-NO3- and 30% N-NH4+ were tested. Experimental units were set up in a completely randomized block design, with four replications. Plants were harvested at 35 days after the seedlings were transplanted to the pots and again at 28 days after the first harvest. After the second harvest, the roots were taken from the substrate. In both growing periods, dry matter yield for plant tops and roots, leaf area, number of expanded green leaves, number of tillers, leaf appearance rate, and phyllochron were significantly affected by the N rates, and the data were adjusted to a second-order model. Aruana grass required high rates of N to show maximum response in those variables.

Saved in:
Bibliographic Details
Main Authors: Lavres Jr.,José, Ferragine,Maria Del Carmen, Gerdes,Luciana, Raposo,Roberto Wagner Cavalcanti, Costa,Michelle Nazaré Xavier da, Monteiro,Francisco Antonio
Format: Digital revista
Language:English
Published: Escola Superior de Agricultura "Luiz de Queiroz" 2004
Online Access:http://old.scielo.br/scielo.php?script=sci_arttext&pid=S0103-90162004000600011
Tags: Add Tag
No Tags, Be the first to tag this record!
Description
Summary:Areas with Aruana grass (Panicum maximum Jacq.) in Brazilian pastures, especially those used by sheep, have expanded due to yield and morphological characteristics of this grass that are favorable to these animals. Nevertheless, the knowledge concerning yield attributes of this grass in relation to nitrogen fertilization is very limited. The objective of this research was to evaluate yield and physiological attributes in this forage grass when grown in nutrient solutions containing N rates. The experiment was carried out in a greenhouse with plastic pots containing ground quartz as substrate, during the Spring season. Six N rates in the solution (14, 112, 210, 294, 378, and 462 mg L-1), with 70% N-NO3- and 30% N-NH4+ were tested. Experimental units were set up in a completely randomized block design, with four replications. Plants were harvested at 35 days after the seedlings were transplanted to the pots and again at 28 days after the first harvest. After the second harvest, the roots were taken from the substrate. In both growing periods, dry matter yield for plant tops and roots, leaf area, number of expanded green leaves, number of tillers, leaf appearance rate, and phyllochron were significantly affected by the N rates, and the data were adjusted to a second-order model. Aruana grass required high rates of N to show maximum response in those variables.