Banca de DEFESA: LUIZ FERNANDO DE SOUSA ANTUNES

Uma banca de DEFESA de DOUTORADO foi cadastrada pelo programa.
STUDENT : LUIZ FERNANDO DE SOUSA ANTUNES
DATE: 28/05/2021
TIME: 09:00
LOCAL: https://conferenciaweb.rnp.br/webconf/norma-gouvea-rumjanek
TITLE:

Efficiency of millicompost in plant development and characterization of the associated microbiome.

KEY WORDS:

Millicomposting. Bacterial community. Microbiome. 16s rRNA. Quality seedlings. Organic agriculture. 

PAGES: 120
BIG AREA: Ciências Agrárias
AREA: Agronomia
SUBÁREA: Fitotecnia
SPECIALTY: Manejo e Tratos Culturais
SUMMARY:

Millicomposting is an environmentally friendly alternative, which enables the production of organic composts from different agricultural residues for later use as a general substrate in the production of seedlings. The objectives of this study were to evaluate the agronomic performance of the lettuce seedlings cultivar Vera, which were produced in the millicompost obtained at 180 days, compared to  a commercial organic substrate (Chapter I); characterize the microbial community present in the millicomposting process by the diplopod Trigoniulus corallinus (Chapter II) and seek new formulations of organic substrates based on millicompost combined with different sources of organic residues, destining them for the production of yellow passion fruit seedlings (Chapter III). In Chapter I, it was found that nitrogen fertilization via castor cake (0, 50, 100 and 200 kg N ha^-1), provided lettuce from seedlings grown in the millicompost with the best agronomic performance independent of the fertilization level, when compared to plants from the commercial substrate. In addition, they were more responsive as the fertilizer doses increased, exhibiting phytotechnical characteristics, physiological indices and higher nutrient accumulation in relation to the plants from the commercial substrate. In Chapter II, it was verified high values for the alpha diversity of the microbiome through the whole process, while the beta diversity showed differences in the community structure between the phases of the millicomposting. The phyla Proteobacteria and Actinobacteria, which represent 70% of the microbiome, are related to the degradation of lignocellulose. The class Alphaproteobacteria and its order Rhizobiales are the most abundant taxa characterized by several species capable to reduce the atmospheric nitrogen. The prevalent orders of the phylum Actinobacteria are Actinomycetales, which predominates at the beginning of the process and Acidimicrobiales, at the end. In addition to these phyla, Bacteroidetes, Planctomycetes, Firmicutes and Acidobacteria, around 5% each, are present. The increase in the relative abundance of Acidobacteria at the end of the process may be related to the maturity of the millicompost, which at 180 days shows a C / N ratio of 15. The most abundant genera were Streptomyces from Actinobacteria and Bacillus from Firmicutes, around 4% each. The microbiome structure and succession along the millicomposting is close to that evidenced during litter decomposition. In Chapter III, the organic substrates S1 (millicompost), S6 (50% millicompost + 50% coconut fiber powder) and S5 (50% millicompost + 50% gliricidia) provided passion fruit seedlings with excellent morphological characteristics and with greater accumulations of P, K Ca and Mg in the dry matter of the aerial part. The substrates S6 and S5 constitute two new options as a sustainable substrate for the production of yellow passion fruit seedlings. The unprecedented valuable information obtained on millicomposting, shows the importance of bacterial communities during the continuous transformation of raw organic matter, in addition to the influence they may have on the development of plants grown in the millicompost.

BANKING MEMBERS:
Presidente - 345.536.817-49 - NORMA GOUVÊA RUMJANEK - EMBRAPA
Interno - 1104775 - ADELSON PAULO DE ARAUJO
Interno - 785.371.857-87 - JOSÉ GUILHERME MARINHO GUERRA - EMBRAPA
Externa à Instituição - JOANA FALCAO SALLES
Externo à Instituição - MARCO ANTONIO DE ALMEIDA LEAL - EMBRAPA