Banca de DEFESA: PRISCILA DORNELAS VALOTE

Uma banca de DEFESA de MESTRADO foi cadastrada pelo programa.
DISCENTE : PRISCILA DORNELAS VALOTE
DATA : 13/07/2018
HORA: 09:00
LOCAL: ANFITEATRO DO INSTITUTO DE ZOOTECNIA DA UFRRJ
TÍTULO:

Forage accumulation and pasture structure of BRS Zuri and BRS Kenya grasses (Megathyrsus maximus) under rotational management.

PALAVRAS-CHAVES:

Keywords: canopy height, light interception, forage mass.

PÁGINAS: 74
GRANDE ÁREA: Ciências Agrárias
ÁREA: Zootecnia
SUBÁREA: Pastagem e Forragicultura
RESUMO:

ABSTRACT
VALOTE, Priscila Dornelas. Forage accumulation and pasture structure of BRS Zuri and BRS Kenya grasses (Megathyrsus maximus) under rotational management. 2018. 39p. Dissertation (Master in Animal Zootechny, Forage and Pasture). Instituto de Zootecnia, Department of Animal Nutrition and Pasture, Federal Rural University of Rio de Janeiro, Seropédica, RJ, 2018.
Considering the recent release of the cultivars Megathyrsus maximus (Syn. Panicum maximum), BRS Zuri and BRS Quênia, and the need to know the effects of the management strategies of their pastures on the responses of plants and animals, this project was elaborated with the objective of evaluating these cultivars when subjected to rotational grazing by dairy cows during the rainy season, under the hypothesis that there is a difference in pasture structure and forage accumulation of these cultivars when managed under the same pre-grazing conditions (95 ± 2 % of LI) and post-grazing (50% of pasture height in pre-grazing). The experiment was conducted in an area belonging to the Embrapa Cattle of Milk, in Coronel Pacheco, under a randomized complete block design, with two treatments (cultivars BRS Zuri and BRS Quênia) and three replications, from November 2016 to August 2017 and November 2017 to April 2018. The height of the canopy was evaluated, the forage mass (FM) and its morphological composition (percentages of leaf blades (LB), stalks (S) and dead material (DM) in FM), the volumetric density of the forage (VFD), besides the accumulation and rate of accumulation for both treatments. Higher pre-grazing heights were observed for BRS Zuri compared to BRS Quênia in 2016/2017 (90,9A ± 1,7cm versus 81,7B ± 1,7cm) and in 2017/2018 (85,8A ± 0,9cm versus 78,1B ± 0,9cm). In 2016/2017 higher FM and VFD were observed for BRS Zuri than for BRS Quênia (7.036A ± 227kg.ha-1 and 38,8A ± 0.9kg.ha-1.cm-1 DM versus 6.419B ± 226kg , and in 2017/2018 mean values of 4.540 ± 142kg.ha-1 and 52,2 ± 16kg.ha-1.cm-1 of DM for both cultivars. Higher DMLB values in 2016/2017 (3.361A ± 86 kg.ha-1 of DM versus 3.132B ± 85kg.ha-1 of DM) and 2017/2018 (2.785A ± 71kg.ha-1 of DM versus 2.481B ± 70kg.ha-1 of MS) were obtained for BRS Zuri in relation to BRS Quênia. The highest PDT in 2016/2017 (473A ± 12tillers.m-2 versus 277 ± 12tillers.m-2) and in 2017/2018 (417A ± 10tillers.m-2 versus 225B ± 10tillers.m-2) occurred for BRS Quênia than for BRS Zuri. Forage accumulation did not vary among cultivars in 2016/2017 (mean of 3.418 ± 202kg.ha-1 of DM) and, in 2017/2018, the highest value was obtained for BRS Zuri (2.272A ± 67kg.ha-1 DM) compared to BRS Quênia (1.938B ± 64kg.ha-1 of DM). In 2016/2017 there was an average forage accumulation rate of 164 ± 9kg.ha-1.dia-1 of DM for both cultivars and, in 2017/2018, the highest forage accumulation rate was obtained to cultivate BRS Zuri (129A ± 4kg.ha-1.dia-1 of DM) in relation to BRS Quênia (110B ± 4kg.ha-1.dia-1 of DM). Both cultivars of M. maximus have potential for use in intensive pasture systems for milk production, with a higher indication for BRS Zuri during the summer and for BRS Quênia, especially during the autumn.

MEMBROS DA BANCA:
Presidente - 1322816 - CARLOS AUGUSTO BRANDAO DE CARVALHO
Interno - 2316004 - RONDINELI PAVEZZI BARBERO
Externo à Instituição - SÉRGIO TRABALI CAMARGO FILHO - OUTRO