Banca de QUALIFICAÇÃO: MARIA FLÁVIA DE SOUZA SEVERO

Uma banca de QUALIFICAÇÃO de MESTRADO foi cadastrada pelo programa.
STUDENT : MARIA FLÁVIA DE SOUZA SEVERO
DATE: 19/12/2022
TIME: 14:00
LOCAL: sala de aula do PPGCAP
TITLE:

Mineral composition of native and exotic forage species in the semi-arid region of Pernambuco

KEY WORDS:

forages, macrominerals, microminerals, mineral nutrition, semi arid and caatinga

PAGES: 45
BIG AREA: Ciências Agrárias
AREA: Zootecnia
SUBÁREA: Nutrição e Alimentação Animal
SPECIALTY: Avaliação de Alimentos para Animais
SUMMARY:

The imbalance of mineral nutrition in ruminants raised on pasture, in the semi-arid region of Pernambuco, directly impacts the efficiency and effectiveness of ruminant production systems, which is why the use of supplements or mineral mixtures has been recommended, in order to supply these mineral deficiencies. However, the high cost of these supplements makes their use in grazing ruminant production systems unfeasible, which highlights the need for knowledge about the macro and micromineral composition of in natura forage species. In view of this, the objective was to evaluate the composition of macro (N, P, K, Mg, Ca, Na and S) and microminerals (Zn, Fe, B, Cu and Mn) of nineteen native and exotic forage species of the semi-arid region of Pernambuco, of which 11 are native - maniçoba, pornunça, sabiá, juazeiro, umbuzeiro, faveleira, catingueira, aroeira, velame, mororó and jurema preta - and 8, exotic - leucena, cunhã, forage watermelon, gliricidia, running grass, herb -salt, signal grass and pigeonpea. The experiment is carried out in the Caatinga Experimental Field and in the native caatinga area, both belonging to the Brazilian Agricultural Research Corporation (Embrapa Semiárido), in Petrolina-PE, where samples were collected from the leaf area and stems, with diameter of, at most, 5 mm, of the forage plants under study, except for the forage watermelon, where the fruits were collected in the same quantities for sampling purposes. These collections were carried out randomly and manually, in four repetitions per species, each repetition consisting of a subsample of three plants. All collected materials were pre-dried in a forced ventilation oven at 55°C for 72 hours, or until complete drying, and subsequently ground in a Willye-type mill, with a 1mm sieve. Part of this material had the organic matter oxidized with HCLO4, to determine the concentrations of P, K, Ca, Mg, S, B, Cu, Fe, Mn, Zn and Na, and the other part was used to determine the levels of N , based on the Kjeldahl method. Na and K concentrations were determined by flame photometry; those of B, by azomethine colorimetry; those of P and S, by spectrometry, with vanadate yellow, and turbidimetry, with barium chloride crystal, respectively. As regards the determination of Ca, Mg, Cu, Fe, Mn and Zn concentrations, atomic absorption spectrometry was carried out using an air-acetylene flame. To analyze the relationship between the physicochemical characteristics of the soil and the composition of minerals present in the native and exotic forage species under study, multivariate analysis of principal components was used, based on the correlation matrix, through the computational program Genes version 2015.5.0. For the main component 1 (CP1), greater interactions were observed between the concentrations of Fe, Zn, K and Mg in the soil; base saturation (V); and Mn, Cu, Na, K, N and Mg from plants. As for the main component 2 (CP2), there were more intense interactions between Ca, Al and P in the soil; electrical conductivity (EC); and soil pH. In addition, from CP1, a close relationship was observed between black jurema, forage watermelon, umbuzeiro, velame, cunhã, mororó, gliricidia, signal grass, catingueira and juazeiro, and, in relation to CP2, there was a close relationship between maniçoba, pornunça, saltbush, current grass, mastic, leucena, sabiá, faveleira and pigeonpea. Therefore, the high correlations of Mn from the plant and Zn, Fe and Mn from the soil determined the soil-plant interactions, under the edaphoclimatic conditions of the semiarid of Pernambuco, and, consequently, determined the grouping of exotic and native forages of the semiarid.

COMMITTEE MEMBERS:
Presidente - ANDRE LUIZ RODRIGUES MAGALHAES
Externo à Instituição - DANIEL BARROS CARDOSO - UFRPE
Externa à Instituição - RAYANNE THALITA DE ALMEIDA SOUZA - IFPI