Banca de DEFESA: SUIANNE LORENA DA SILVA E SILVA

Uma banca de DEFESA de MESTRADO foi cadastrada pelo programa.
STUDENT : SUIANNE LORENA DA SILVA E SILVA
DATE: 21/11/2022
TIME: 14:00
LOCAL: Auditório da zootecnia profissional
TITLE:

EVALUATION OF CULTIVARS OF Megathyrsus sp. AND Urochloa sp. UNDER HARVEST FREQUENCIES FOR SILAGE PRODUCTION IN THE AMAZON BIOME

KEY WORDS:

Forage conservation; Physiological maturity; Tropical grasses.

PAGES: 78
BIG AREA: Ciências Agrárias
AREA: Zootecnia
SUBÁREA: Pastagem e Forragicultura
SPECIALTY: Avaliação, Produção e Conservação de Forragens
SUMMARY:

The objective of the present work was to evaluate seven cultivars of tropical grasses of the genera Megathyrsus sp. and Urochloa sp. under three harvest frequencies for silage production in the Amazon biome. The field experiment was carried out in the experimental area of the Igarapé-açu school farm (FEIGA) of the Universidade Federal Rural da Amazônia (UFRA). The design used was in randomized blocks, in a factorial arrangement of 7 × 3, with seven cultivars of tropical grasses and three cutting frequencies, with four blocks (n = 84). The cultivars evaluated were Urochloa (syn. Brachiaria) brizantha cv. Xaraés, U. brizantha cv. BRS Piatã, Uroclhoa sp. cv. Mavuno (hybrid: B. ruziziensis x B. brizantha, Uroclhoa sp. cv. BRS Ipyporã (hybrid: B. ruziziensis x B. brizantha), Megathyrsus maximus (syn. Panicum maximum) cv. BRS Kenya, M. maximus cv. BRS Tamani and M. maximus BRS Zuri. Cutting frequencies were 30, 60 and 90 days at a residual height of 20 cm. Morphogenic and structural characteristics were evaluated, forage production in the rainy season, nutritional value and forage production in the less rainy period, in addition to the seasonality of natural and dry matter in the seasons. The data were subjected to descriptive analysis, normality tests and ANOVA (proc glimmix) The fixed effects of Cultivar (C), Harvest frequency (FC), the C×FC interaction, the random block effect and the experimental error were considered in the statistical model. averages were compared using the Tukey test. Statistical analyzes were performed in the SAS Studio software, through the online platform Sas OnDemand for Academics, considering 0.05 as a significance level. In view of the above, it is possible to see that grasses harvested at a frequency of 30 days provide forage of greater nutritional value, related to a frequency of 90 days. However, there is a need to carry out more harvests during the year, increasing costs. Climatic conditions exerted considerable influence on the performance of grasses such as Kenya and Tamani. However, they provided an increase in the development of Zuri grass during the wettest period of the year. Cultivars of the genus Urochloa such as Xaraés, Piatã and Mavuno showed characteristics of greater flexibility to climatic conditions compared to grasses of the genus Megathyrsus without affecting their production, enhancing the adaptability of these grasses to different regions. Thus, it is possible to observe the different characterization scenarios of grasses of the genus Megathyrsus and Urochloa in view of their morphogenic, structural, nutritional and productive characteristics, with variations during the seasons and thus composing a range of options for the production of silage in the different regions of Brazil.

BANKING MEMBERS:
Externo à Instituição - ANIBAL COUTINHO DO REGO
Externo ao Programa - 1974699 - EBSON PEREIRA CANDIDO
Externo à Instituição - EDSON MAURO SANTOS - UFPB
Externo à Instituição - JOÃO LUIZ PRATTI DANIEL - UFPR
Presidente - 1331235 - THIAGO CARVALHO DA SILVA
Externo à Instituição - WILTON LADEIRA DA SILVA - UFG