Banca de DEFESA: JULIANA BARROS RAMOS

Uma banca de DEFESA de DOUTORADO foi cadastrada pelo programa.
DISCENTE: JULIANA BARROS RAMOS
DATA: 29/09/2022
HORA: 15:00
LOCAL: Defesa remota via Google Meet
TÍTULO:

Cercosporiosis resistance and cercosporin production in coffee genotypes

PALAVRAS-CHAVES:

Cercospora coffeicola, genetic resistance, mycotoxin.

PÁGINAS: 66
GRANDE ÁREA: Ciências Agrárias
ÁREA: Agronomia
SUBÁREA: Fitossanidade
ESPECIALIDADE: Fitopatologia
RESUMO:

Cercosporiosis, caused by the necrotrophic fungus Cercospora coffeicola, which is characterized by producing a red toxin, cercosporin, of high toxicity to plant tissues. It is a disease that leads to significant losses in coffee production, as it causes damage to seedlings in nurseries and adult plants by defoliation, in addition to impairing the quality of the beverage, due to the occurrence of lesions on fruits. Disease control is carried out through cultural practices and the application of fungicides. However, one of the biggest challenges for researchers has been to determine efficient methods of control with low environmental impact and the search for resistant cultivars meets this challenge. Thus, this study aimed to search for resistance to brown eye spot of coffee in coffee genotypes. To determine the contents of total soluble lignin and total soluble phenolic compounds in genotypes contrasting in terms of resistance. To quantify the cercosporin levels in coffee leaves of the genotypes of Coffea arabica Mundo Novo 376/4, Catuaí Vermelho IAC 99, IPR 102, Topázio MG 1190) and C. canephora (Clone 213) with symptoms of brown eye spot using high performance liquid chromatography (HPLC). Seedlings of 19 commercial cultivars and 41 accessions from the germplasm bank of Minas Gerais were inoculated with spores of five isolates of C. coffeicola, obtained from different coffee growing regions. The experimental design used was complete randomized blocks, with eight replications and two plants per experimental plot. The MG-1207 Sumatra genotype showed the highest level of resistance to brown eye spot. The quantification of lignin content and phenolic compounds were not related to brown eye spot resistance in the coffee genotypes MG-1207 Sumatra, MG 0291 and Catuai Vermelho IAC 144. To quantify cercosporin, leaves of C. arabica (Mundo Novo 376/4, Catuaí Vermelho IAC 99, IPR 102, Topázio MG 1190) and C. canephora (Clone 213) with symptoms of Cercoporiosis were collected. Samples were macerated and extraction was performed using chloroform. Cercosporin was detected in all genotypes evaluated, validating the HPLC method for quantification of the toxin in coffee leaves.

MEMBROS DA BANCA:
Externo à Instituição - WILLIAN CÉSAR TERRA - UFLA (Suplente)
Interno - PAULO ESTEVAO DE SOUZA (Membro)
Presidente - MARIO LUCIO VILELA DE RESENDE (Membro)
Externo à Instituição - JULIANA COSTA DE REZENDE ABRAHÃO - EPAMIG (Membro)
Externo à Instituição - DEILA MAGNA DOS SANTOS BOTELHO - UFLA (Membro)
Externo à Instituição - CRISTIAN DAVID PLAZA PEREZ - UDLA (Membro)
Externo à Instituição - CESAR ELIAS BOTELHO - EPAMIG (Suplente)