Banca de DEFESA: LUANA MARQUES DOS SANTOS

Uma banca de DEFESA de MESTRADO foi cadastrada pelo programa.
STUDENT : LUANA MARQUES DOS SANTOS
DATE: 24/03/2023
TIME: 09:00
LOCAL: Garanhuns/PE- UFAPE
TITLE:

Fractionation of carbohydrates, degradability and in vitro gas production of cactus cladodes irrigated with brackish water and doses of organic matter

KEY WORDS:

cactus, carbohydrate fractionation, semiarid

PAGES: 69
BIG AREA: Ciências Agrárias
AREA: Zootecnia
SUBÁREA: Pastagem e Forragicultura
SPECIALTY: Manejo e Conservação de Pastagens
SUMMARY:

The Brazilian semiarid region is characterized by a negative water balance, acting, therefore, as a limiting factor for forage production, especially in the dry season. In this way, the use of brackish water presents itself as a relevant strategy, in order to guarantee the production of forage biomass adapted to the climatic conditions of this region, such as cactus cladodes, a plant with acid metabolism of crassulaceans, exalted by the efficient use of Water. Thus, the objective was to evaluate the effect of irrigation with brackish water and doses of organic fertilizer on aspects of fractionation of total carbohydrates, degradability and kinetics of ruminal fermentation, through the in vitro technique of gas production, of forage cactus at different stages. phenological, in the semiarid region of Pernambuco, in a cycle of 18 months. The experiment was carried out in the area of Prospecting and Studies in Biosaline Agriculture of the experimental field of the caatinga, belonging to EMBRAPA Semiárido, in Petrolina-PE. A randomized block design (DBC) was used in a 5 x 4 factorial arrangement, consisting of five irrigation depths with brackish water (L0%, L12.5%, L25%, L37.5%, L50% ETo) and four doses of organic fertilizer (0, 15, 30 and 45 Mg.ha^-1), totaling 80 plots. Each one containing 50 plants, of these, 32 plants referring to borders, remaining 18 plants per plot, among them, six central plants were used for the evaluations. The cladodes were collected, cut into small pieces, pre-dried in a forced ventilation oven at 55°C and ground to 2 mm and 1 mm. The bromatological and gas production analyzes were carried out at the Animal Nutrition (LANA) and Gas Production Laboratories, at the Laboratory Center for Research Support of the Academic Unit of Garanhuns (CENLAG), at the Federal University of Agreste Pernambuco. Interaction was observed between the depths of brackish water (LA) and the doses of organic matter (AO), in relation to the concentrations of total carbohydrates (TC) (P=0.032), with a higher content of CHOT in AO of 45Mg.ha^-1 and LA of L0% ETo. For fraction A+B1, an increasing quadratic effect was observed for both LA and AO (P=0.000). The control treatment (L0% ETo and 0 Mg.ha^-1 dose) provided higher concentrations of A+B1 (745.01 g.kg^-1 DM and 728.19 g.kg^-1 DM). An increasing quadratic effect was observed for the B2 fraction both with regard to LA and AO (P=0.000), with a higher concentration of this fraction in the LA of L37.5% ETo and in the AO of 30 Mg.ha^-1. Fraction C showed a decreasing quadratic effect in relation to LA (P=0.000), with higher concentration at the L25% ETo depth (59.44 g.kg^-1 DM). There was an increasing quadratic effect of AO in relation to effective degradability (ED), with a passage rate of 2% h^-1 and 5% h^-1 (P<0.000), with a lower concentration at the dose of 15 Mg.ha^-1. However, there was a negative linear effect, for DE, in relation to the increase in LA (P = 0.019). The total production of gases, under the isolated effect of the LA, showed an increasing quadratic effect (P=0.025), with a greater response in the LA of 12.5% ETo (~257.77 ml) and, under the effect of the AO, it was observed positive linear behavior (P=0.009). As for the volume of gas produced by fractions A+B1, an isolated effect was observed for LA (P=0.001), with a negative linear behavior (183.30 ml to 161.87 ml). Similarly, an isolated effect was observed for the AO, however with decreasing quadratic behavior (P = 0.001). An isolated, linear and negative effect was observed for LA, both in relation to the rate of degradation of non-fibrous carbohydrates (P= 0.001) and in relation to the rate of degradation of fibrous carbohydrates (P<0.000). Therefore, forage cactus, the Mexican elephant ear variety, is sensitive to salinity, albeit at low electrical conductivity (1.73 ds.m^-1) and sodicity.

COMMITTEE MEMBERS:
Presidente - ALBERICIO PEREIRA DE ANDRADE
Externo à Instituição - DANIEL BARROS CARDOSO
Externa à Instituição - RAYANNE THALITA DE ALMEIDA SOUZA