Structural and morphogenetic responses of aruana grass to cutting severities and nitrogen fertilization

• Grant number: 12/07020-4
• Support Opportunities: Regular Research Grants
• Start date: August 01, 2012
• End date: July 31, 2014
• Field of knowledge: Agronomical Sciences - Animal Husbandry - Pastures and Forage Crops
• Principal Investigator: Alessandra Aparecida Giacomini
• Grantee: Alessandra Aparecida Giacomini
• Host Institution: Instituto de Zootecnia. Agência Paulista de Tecnologia dos Agronegócios (APTA). Secretaria de Agricultura e Abastecimento (São Paulo - Estado). Nova Odessa , SP, Brazil
• Associated researchers: Flavia Maria de Andrade Gimenes ; Ivani Pozar Otsuk ; Karina Batista ; Linda Monica Premazzi ; Luciana Gerdes ; Waldssimiler Teixeira de Mattos

Abstract

Cutting severity and nitrogen fertilization trigger physiological and morphological changes in individual plants, altering tissue flows, forage production and nutritional value of forage grasses. In this context, the objective of this study is to evaluate the morphogenesis and structural characteristics of aruana grass subjected to defoliation severity and nitrogen, and their effects on forage production, root system and nutritional value. It was hypothesized that both the nitrogen nutrition as the cutting severity can promote changes in their growth dynamics. Cylinders will be collected with plant + soil in a aruana grass pasture established in 2001 in a Argissolo Amarelo, and the experiment will be conducted in a greenhouse. The treatments correspond to four levels of nitrogen (50, 100, 150 and 200 mg/dm3) and two defoliation severities (10 and 20 cm height), in a randomized complete block design with four replications and 4 x 2 factorial arrangement. The results regarding the morphogenetic and structural characteristics, forage accumulation and its morphological components, tillering dynamics and the SPAD value will be subjected to analysis of variance using PROC MIXED (SAS). The results for root system, total forage mass and nutritional value will be subjected to analysis of variance using PROC GLM (SAS). (AU)