Banca de DEFESA: GUILHERME ALVES DO VAL

Uma banca de DEFESA de MESTRADO foi cadastrada pelo programa.
DISCENTE : GUILHERME ALVES DO VAL
DATA : 25/07/2019
HORA: 09:00
LOCAL: INSTITUTO DE ZOOTECNIA DA UFRRJ
TÍTULO:

Evaluation of Tithonia diversifolia under different residue heights

PALAVRAS-CHAVES:

Chemical Composition, Fractionation, Energy Value

 

PÁGINAS: 31
GRANDE ÁREA: Ciências Agrárias
ÁREA: Zootecnia
SUBÁREA: Pastagem e Forragicultura
RESUMO:

The objective of the present study was to evaluate the productive behavior and chemical-bromatological composition of Tithonia diversifolia managed at different residue heights. The experiment was conducted at the Animal Science Institute of UFRRJ, in Seropédica-RJ, from 07/07/2018 to 04/18/2019. Preliminary preparation of the experimental area with limestone distribution, plowing and harrowing 60 days before planting, in addition to fertilization, at the time of planting and 60 days after. The planting was done with cuttings 30cm long, two thirds in the ground and one third outside, in experimental areas arranged in 3 completely randomized blocks. The blocks were divided in eight plots of 3.0 x 3.5 m, totaling 112 m² per block, where four treatments were allocated (residue heights), 20, 40, 60 and 80 cm. The experimental design was completely randomized blocks in a subdivided plot scheme with two replicates per block. The evaluations were carried out every 57 days, where the heights of the plants were measured in each plot, in a central area of 4 m², with subsequent collection of the green mass. The collected mass was directed to the laboratory where it was determined the yield of green and dry mass, growth rate, morphological composition, leaf:stem relation, DM, CP, MM, EE, GE, NDF, NDFap, ADF, ADIP, NDIP , fractionation of carbohydrates and proteins, TDN, DE, MEP and NEL. The data were submitted to analysis of homogeneity, normality, ANOVA and Tukey's test at 5% of significance, using the statistical software R. There was treatment effect and month for H and TC (p <0.05) and month for LSR (p <0.05). Higher values of H were observed for the highest residue heights, but the GR values were higher for the treatments of smaller height, resulting from greater stem elongation. YGM, YDM, AGM and ADM were not influenced by the treatment (p> 0.05), only for month (p <0.05). It was verified that the highest values were the result of the months of greatest rainfall and temperature. There was treatment effect (p <0.05) for CP, NDF and ADF, and month effect (p <0.05) for DM, CP, MM, EE, NDF, ADF and LIG. The lowest values of DM were observed in the months of lower rainfall, probably due to the lower tugor in the plant cells. CP was higher for treatments with higher residue height, probably due to the greater amount of leaf in the composition of the analyzed material and for the months with lower cell wall content, mainly LIG. The content of MM is in agreement with those reported in the literature, as the family Asteraceae possesses the ability to accumulate inorganic salts in its leaves. EE was similar in all treatments, being a stable component. However, the possible variations were due to the climatic conditions, and the response of T. diversifolia with a higher amount of lipids was for protection. The contents of NDF and ADF showed the same behavior, observing lower levels in treatments with higher residue height, RFH that was higher in these treatments. The increase in the number of NDF, ADF and LIG between the months may be due to possible lignified stems near the cutoff region of each treatment. Under the conditions studied, the treatment of 20 cm showed to be the best management of height of residue, due to the nutritional and productivity values, in addition to the greater use of the field material.

 

MEMBROS DA BANCA:
Externo à Instituição - DOMINGOS SAVIO CAMPOS PACIULLO - EMBRAPA
Externo à Instituição - FÁBIO TEIXEIRA DE PÁDUA - IFRJ
Presidente - 387749 - JOAO CARLOS DE CARVALHO ALMEIDA