Banca de DEFESA: DIEGO TEIXEIRA DE OLIVEIRA

Uma banca de DEFESA de MESTRADO foi cadastrada pelo programa.
STUDENT : DIEGO TEIXEIRA DE OLIVEIRA
DATE: 22/08/2023
TIME: 09:00
LOCAL: meet.google.com/zet-wxai-wbf
TITLE:

Substrate for organic vegetable seedlings obtained with the addition of biochar before and after composting elephant grass and cattle manure.

KEY WORDS:

Lettuce, seedlings, organic substrate.

PAGES: 45
BIG AREA: Ciências Agrárias
AREA: Agronomia
SUBÁREA: Ciência do Solo
SPECIALTY: Fertilidade do Solo e Adubação
SUMMARY:

With the change in the organic legislation, in Ordinance nº 52 of 2021, and Ordinance nº 404 of 2022, the use of seedlings produced in conventional systems will gradually reduce, and the end of their use should be within five years after the publication of the Ordinance. Thus, it becomes necessary to look for materials and methods that can produce organic substrates from locally available inputs. The Vale do Rio Pardo region, in Rio Grande do Sul, has an abundance of elephant grass and cattle manure in agricultural units, and biochar is also available in charcoal kilns in the region. Already commonly used in the formulation of other substrates, the research set out to find possibilities for substrates that, in addition to being organic, allow autonomy for farmers. For this, the objective of this work was to evaluate the performance of organic substrates for vegetable seedlings formulated from composting elephant grass, bovine manure and different amounts of biochar (0%, 10%, 20% and 40%). The contents of C, N, Ca, Mg, P and K, the total contents of C and N, the C/N ratio of the compounds, analysis of pH and electrical conductivity, potential emissions of CO2 and NH3 in the compost were evaluated in the compost. over 90 days of composting. Then, an experiment was carried out with the production of organic lettuce seedlings (Lactuca sativa), which evaluated the performance of substrates formulated with organic compost, containing different amounts of biochar (0%, 10%, 20% and 40%) added before and after the composting process, another control treatment consisting of the Carolina Soil commercial substrate. In the substrates, chemical evaluations of the nutrients C, N, Ca, Mg, P and K, electrical conductivity and pH, analysis of heavy metals, physics of apparent density and the development of seedlings, through seedling height, number of leaves , fresh mass of shoots, volume of roots and degree of root stability. As for the number of leaves and stability of the clod, there was no significant variation, in terms of plant height, the treatment with 40% biochar before and after composting showed a lower height than the other treatments and the commercial substrate, even lower. In the analysis of shoot mass, treatment with 10% of biochar added after composting showed the best performance, followed by treatments without biochar and with 20% of biochar added after composting. The treatment with 20% of biochar added before composting showed better indices of root volume, shoot (Height, mass and number of leaves) was the treatment with 10% of biochar added after composting

COMMITTEE MEMBERS:
Presidente - ***.790.757-** - MARCO ANTONIO DE ALMEIDA LEAL - EMBRAPA
Externo à Instituição - JOSÉ ANTÔNIO KROEFF SCHMITZ
Externa à Instituição - MARTA SANDRA DRESCHER