Banca de DEFESA: VINICIO OLIOSI FAVERO

Uma banca de DEFESA de DOUTORADO foi cadastrada pelo programa.
STUDENT : VINICIO OLIOSI FAVERO
DATE: 12/08/2022
TIME: 08:30
LOCAL: videoconferência
TITLE:

Isolamento, caracterização e eficiência simbiótica de bactérias isoladas de nódulos de feijão-mungo [Vigna radiata (L.) Wilczek]: otimização da fixação biológica de nitrogênio através da inoculação

KEY WORDS:

Vigna radiata. Selection of efficient rhizobia. Biological nitrogen fixation.

PAGES: 156
BIG AREA: Ciências Agrárias
AREA: Agronomia
SUBÁREA: Ciência do Solo
SUMMARY:

The objective of this study was to evaluate the nodulation of mung bean [Vigna radiata (L.) Wilczek] with rhizobia native to Brazilian soils, isolate the associated rhizobia, characterize them and evaluate them in terms of nodulation capacity and symbiotic efficiency.  In Chapter I, the nodulation of two mung bean genotypes by native rhizobia in ten Brazilian soils was evaluated, in addition to the isolation of bacteria present in the nodules, followed by morphogenetic characterization and evaluation of the nodulation capacity. In general, plants grown in soil samples from the Southeast region showed higher nodulation and growth compared to those grown in samples from the Midwest region. From the nodules, 101 bacteria were obtained: Bradyrhizobium (66), Rhizobium (19), Mesorhizobium (4), Ensifer (3), Leifsonia (3), Bacillus (3), Agrobacterium (1), Mycolicibacterium (1) and Kaistia (1). Bradyrhizobium isolates were the only ones capable of nodulating mung bean, and those from soils in the Southeast region were the most efficient; as for the phylogenetic group, in general, isolates close to the group of Bradyrhizobium yuanmingense were more efficient. In Chapter II, the microbiome characterization of the nodules of two mung bean genotypes cultivated in samples of ten Brazilian soils was performed, using the 16S rRNA gene sequencing technique by NGS (Next-Generation Sequencing) Illumina MiSeq. OTU0001 (Operational Taxonomic Units) belonging to the Bradyrhizobium genus represented more than 99% of the recovered sequences. Pseudomonas was the most abundant non-rhizobia genera, and was present only in nodules of the MGS Esmeralda cultivar, revealing a difference in specificity between genotypes. In Chapter III, the inoculation of 31 Bradyrhizobium isolates compared to native rhizobia in mung bean grown in pots with soil was evaluated, including the evaluation of the application of N rates at sowing. The inoculation of the isolates resulted in increments of up to 79% in nodule weight, 66% in shoot dry weight, and of 55% in the accumulated N from the FBN compared to the treatment without inoculation, however, they had less growth than treatment with N fertilizer (160 kg ha^-1 of N). When under application of N doses at sowing, there were increases in plant development, but with a reduction in nodulation. In Chapter IV, the inoculation potential of mung bean was verified through cross-inoculation with elite Bradyrhizobium strains used in commercial inoculants for soybean and cowpea in Brazil, in addition to a comparison with isolates obtained from mung bean nodules. The strains SEMIA 587 (B. elkanii) recommended for soybean, and the strains UFLA 3-84 (B. viridifuturi), BR 3267 (B. yuanmingense), and INPA 3-11B (B. elkanii) recommended for cowpea were able to to nodulate the mung bean. SEMIA 587, UFLA 3-84, and mung bean isolates showed greater efficiency in nodulation and plant growth, and therefore, may contribute to mung bean inoculation in Brazil.

BANKING MEMBERS:
Interno - 1104775 - ADELSON PAULO DE ARAUJO
Externo à Instituição - ENDERSON PETRONIO DE BRITO FERREIRA - EMBRAPA
Interno - ***.881.579-** - JERRI ÉDSON ZILLI - EMBRAPA
Externa à Instituição - LINDETE MIRIA VIEIRA MARTINS - UNEB
Presidente - ***.898.198-** - SEGUNDO SACRAMENTO URQUIAGA CABALLERO - EMBRAPA