Banca de QUALIFICAÇÃO: Henrique de Sousa Honorato

Uma banca de QUALIFICAÇÃO de DOUTORADO foi cadastrada pelo programa.
STUDENT : Henrique de Sousa Honorato
DATE: 08/11/2022
TIME: 08:00
LOCAL: Videoconferência - Teams
TITLE:

Metagenomics and genetic structure of begomoviruses of weeds associated with tomato crops in Brazil.

KEY WORDS:

Begomovirus, weeds, Fabaceae, Malvaceae, Solanaceae, High-Throughput Sequencing.

PAGES: 124
BIG AREA: Ciências Biológicas
AREA: Biologia Geral
SUMMARY:

The cultivation of tomato (Solanum lycopersicum L.) has economic and social importance for the agricultural sector in Brazil, as well as for the producing regions of the Federal District (DF) and surroundings. Tomato production costs fluctuate, with the occurrence of diseases and pests/vectors being one of the main reasons. In this context, begomoviruses (caused by species of Begomovirus, family Geminiviridae) stand out. These viruses have one or two molecules of single-stranded circular DNA, encapsidated by particles of 18-30 nanometers. Viral isolates with a bipartite genome (having the DNA-A and DNA-B components) predominate in tomato plants in Brazil. Begomoviruses are transmitted with great efficiency by the whitefly vector [Bemisia tabaci MEAM-1 (Middle East Asian Minor-1 = biotype B)], which has a wide distribution, high adaptability to different environmental conditions and an extensive host circle, including several weeds. The introduction of B. tabaci MEAM 1 in the DF in the early 1990s was the triggering factor for epidemics of begomoviruses in tomato, with a subsequent increase in the number of new species of Begomovirus. The presence of weeds, mainly classified in the Malvaceae, Solanaceae and Fabaceae families, in and/or close to tomato crops can interfere with the epidemiological cycles and population structure of begomoviruses by allowing the permanence and/or fixation of viral isolates under natural conditions. Mixed infections of viruses with bipartite genomes are common in weeds, providing a range of begomovirus-begomovirus-like interactions within host plant cells. These viral interactions facilitate the occurrence of natural mechanisms that generate viral variability such as recombination and pseudorecombination, which can lead to the generation of new variants. Studies of viral populations or communities are becoming faster, broader and less expensive with the advent of more improved technologies like High-Throughput Sequencing (HTS). Virome-type analyzes performed by combining metagenomics and HTS allow a better understanding of viral diversity. In this context, the present project has the general objective to prospect the diversity of begomoviruses in weeds commonly found in association with tomato cultivation and to elucidate aspects about the potential role of these plants in the evolution and genetic structure of populations of begomoviruses that infect this Solanaceae in the Federal District (DF) and in Brazil.

BANKING MEMBERS:
Externa à Instituição - MIRTES FREITAS LIMA - EMBRAPA
Externo ao Programa - 1701961 - CLEBER FURLANETTO
Interno - 2210861 - JOSE RICARDO PEIXOTO
Interno - 6404906 - JUVENIL ENRIQUE CARES
Interno - 1351999 - LUIZ EDUARDO BASSAY BLUM
Presidente - 1723060 - RITA DE CASSIA PEREIRA CARVALHO