Banca de QUALIFICAÇÃO: EMMANUEL LIEVIO DE LIMA VERAS

Uma banca de QUALIFICAÇÃO de MESTRADO foi cadastrada pelo programa.
DISCENTE : EMMANUEL LIEVIO DE LIMA VERAS
DATA : 26/06/2017
HORA: 14:00
LOCAL: Sala de videoconferência do CVT - EAJ
TÍTULO:

Morphogenesis and accumulation of biomass of Brachiaria cultivars in Northeast Brazil

PALAVRAS-CHAVES:

elongation rate, regrowth, selection of cultivars, tillering

PÁGINAS: 75
GRANDE ÁREA: Ciências Agrárias
ÁREA: Zootecnia
SUBÁREA: Pastagem e Forragicultura
ESPECIALIDADE: Avaliação, Produção e Conservação de Forragens
RESUMO:

The objective was to evaluate the morphogenic and structural characteristics of forage cultivars under the edaphoclimatic conditions of the Northeast of Brazil. The experiment was conducted in the Experimental Area of the Forage Research Group (GEFOR), located in the Academic Unit of the Agricultural Sciences - UFRN, Macaíba / RN, with a duration of 356 days, from April 2016 to April 2017. The evaluated forages Were of the species of Brachiaria brizantha cultivars: Marandú, Paiaguás, Piatã and Xaraés; Brachiaria decumbens cv. Basilisk. The experimental area was 750 m2, with 20 plots divided into four blocks. The size of each plot was 2.0 m X 2.0 m = 4.0 m 2. The variables analyzed were: forage mass and morphological components (leaf blade, stem and dead material), accumulation rate, leaf: stem and live ratio: dead, leaf length, phyllochron, leaf life span, appearance rate Of leaves, leaf elongation rate, senescence rate, shoot elongation rate, number of live leaves, classification and characteristics of individual tillers, canopy height, light interception and leaf area index. There was no cultivar x cut interaction for the total forage mass (MFT) (P = 0.7857), however, differences between cultivars were observed (P = 0312), the highest MFT was observed in the Xaraés and the lowest in Paiaguás. The highest production of leaf blades was recorded in the Xaraés grass (P = 0.0000), and the highest in the basilisk grass (P = 0.0000). The highest percentage of dead material (P = 0.0012) was observed in Paiaguás cultivar. There was a seasonal effect for evaluation of the morphogenic characteristics, the smaller phyllochrons and numbers of live leaves were recorded during the water season. During this period, leaf life was also shorter, leaf appearance increased and leaf length increased. Differences among cultivars (P = 0.0000) were observed for individual tiller characteristics, while Xaraés grass presented a longer tiller length. There was a cultivar x cut (P = 0.0151) interaction for the dry weight of the tillers with the highest weight recorded in the Xaraés cultivar. The highest population density of tillers was verified in the Basilisk cultivar (P = 0.0224). The morphogenic and structural responses of  Brachiaria cultivars demonstrate the adaptation of these cultivars to the ecosystem of the coastal region of Northeast Brazil.

MEMBROS DA BANCA:
Presidente - 986835 - GELSON DOS SANTOS DIFANTE
Interno - 2339534 - STELA ANTAS URBANO
Externo à Instituição - JOÃO VIRGINIO EMERENCIANO NETO - UNIVASF