Banca de DEFESA: OTÁVIO TAVARES MEDEIROS

Uma banca de DEFESA de MESTRADO foi cadastrada pelo programa.
STUDENT : OTÁVIO TAVARES MEDEIROS
DATE: 31/07/2024
TIME: 08:00
LOCAL: Universidade Federal do Agreste de Pernambuco
TITLE:

Agronomic Assessment and Nutritional Value of Urochloa Clones in Rainfed Conditions

KEY WORDS:

Forage production; digestibility; morphological structures.

PAGES: 52
BIG AREA: Ciências Agrárias
AREA: Zootecnia
SUBÁREA: Pastagem e Forragicultura
SUMMARY:

Research has been directed towards plant genetic improvement aiming to obtain hybrids that adapt to current environmental conditions. Therefore, the aim was to evaluate the structural characteristics, mass production, nutritive value and efficiency of the GP-3025 hybrid (Camello) in Agreste region of Pernambuco. The experiment was conducted at Paulista Farm, a property partnered with the Federal University of Agreste of Pernambuco, along with Papalotla Seeds company. The experimental design used was a randomized complete block design (RCBD), with two treatments (U. brizantha cv. Marandu and hybrid GP-3025), distributed over two years with eight replications, corresponding to evaluation paddocks measuring 34 x 35 m totaling an area of 1,190 m² per paddock. Significant effects were observed for leaf/stem ratio (P=0.0132) in the first year with a higher ratio. Differences in tillering (P<0.0237) were noted across the years. Regarding total forage mass production, no interaction effect was observed between evaluation year and grasses (P=0.3895). Chemical composition showed no interaction effect between evaluation year and grasses for variables such as DM (P=0.465), ash (P=0.775), crude protein (P=0.352), hemicellulose (P=0.597), cellulose (P=0.097), and total carbohydrates (P=0.181). Significant differences were found for lignin (P<0.001) and total non-fibrous carbohydrates (P<0.001), with the hybrid showing higher concentrations in the first year than in the second. Crude fiber content exhibited interaction effects between evaluation year and grasses (P=0.002), with the hybrid being higher in the second year (694.4g.Kg-¹ vs. 636.6g.Kg-1 for Marandu). Similarly, significant interactions were observed for NDF (P<0.001) and ADF (P<0.001). Parameter A showed a significant effect for the year (P=0.031), while parameter C did not show significant effects for grass species (P=0.908), but significant effects were observed for the hybrid in the subsequent year, showing better levels in the second year (42.43% vs. 31.84% respectively). Parameter DP had a significant effect in the first year (P<0.05), while DE (2%) showed no significant effect (P>0.05), DE (6%) had a significant effect (P<0.05), and DE (8%) showed a significant effect for grass species (P=0.046). Digestibility coefficients showed significant effects for the year (P=<0.0001). In conclusion, the use of the GP-3025 hybrid shows promising characteristics in terms of nutritive value and adaptation to environmental conditions in the region. These results suggest it could be a viable alternative to improve forage production in the Agreste region of Pernambuco.

 

COMMITTEE MEMBERS:
Interna - DULCIENE KARLA DE ANDRADE SILVA
Externo à Instituição - GEOVERGUE RODRIGUES DE MEDEIROS - INSA
Externo à Instituição - GLESSER PORTO BARRETO