Banca de QUALIFICAÇÃO: MATEUS RIBEIRO PIZA

Uma banca de QUALIFICAÇÃO de DOUTORADO foi cadastrada pelo programa.
DISCENTE: MATEUS RIBEIRO PIZA
DATA: 22/01/2026
HORA: 08:00
LOCAL: Remota via Google Meet meet.google.com/wot-fgjd-qqx
TÍTULO:

Photosynthetic and enzymatic responses associated with coffee leaf rust resistance in Icatu
derived Coffea arabica progenies

PALAVRAS-CHAVES:

Coffee, Hemileia vastatrix, chlorophyll fluorescence, antioxidant enzymes,
Resistance.

PÁGINAS: 23
GRANDE ÁREA: Ciências Agrárias
ÁREA: Agronomia
SUBÁREA: Fitotecnia
ESPECIALIDADE: Melhoramento Vegetal
RESUMO:

Coffee leaf rust (CLR), caused by Hemileia vastatrix Berk. & Broome., is one of the main
problems on Arabica coffee (Coffea arabica L.) production worldwide. Given the above, we
aimed to evaluate arabica coffee genotypes derived from Icatu to identify progenies resistant to
coffee leaf rust and characterize the physiological and enzymatic mechanisms associated with
the response to infection. Twenty-eight progenies in the F 4:5 generation and two commercial
cultivars were evaluated. Seedlings with four to six pairs of leaves were used to set up the
experiments in a randomized block design (RBD), kept in a greenhouse and inoculated with H.
vastatrix spores. The evolution of CLR was measured by severity. The results were the basis for
applying a selection intensity of 10%, also considering the yield and the vigor. The selected
progenies were evaluated for chlorophyll fluorescence, and new seedlings were prepared for the
evaluation of the activity of the antioxidant enzymes superoxide dismutase (SOD) and catalase
(CAT) at 0, 24, 48, 72, and 96 hours after inoculation in an additional RBD experiment. The
results revealed significant variability in resistance among genotypes, with 32% of the progenies
classified as immune or resistant. Infection reduced photochemical efficiency, indicating
oxidative damage in the reaction centers, while the progenies characterized as resistant,
especially P19, maintained higher values of ΦPSII, electron transport rate (ETR), and non-
photochemical dissipation (NPQ), evidencing greater photoprotective capacity. The presence of
resistance in the evaluated progenies is related to fast activation of the antioxidant system,
evidenced by significant increases in SOD and CAT activity. These findings contribute to the
understanding of coffee plants mechanisms to H. vastatrix and contribute to the development of
resistant varieties.

MEMBROS DA BANCA:
Externo à Instituição - VINÍCIUS TEIXEIRA ANDRADE - EPAMIG (Membro)
Externo ao Programa - TIAGO TERUEL REZENDE - DAG/ESAL (Membro)
Externo à Instituição - GUILHERME BARBOSA ABREU - EMBRAPA (Membro)
Externo à Instituição - ANDRÉ DOMINGHETTI FERREIRA - EMBRAPA (Suplente)
Presidente - ADRIANO TEODORO BRUZI (Membro)