Banca de QUALIFICAÇÃO: THAIS FRANCA SILVA

Uma banca de QUALIFICAÇÃO de DOUTORADO foi cadastrada pelo programa.
STUDENT : THAIS FRANCA SILVA
DATE: 13/03/2023
TIME: 08:30
LOCAL: Videoconferência - Teams
TITLE:

"Etiology and development of an efficient method for detecting the causal agent of avocado dieback."

KEY WORDS:

Persea americana, Botryosphaeriaceae, Diversity, Detection.

PAGES: 78
BIG AREA: Ciências Biológicas
AREA: Biologia Geral
SUMMARY:

Avocado demand has increased due to the dissemination of the fruit's health benefits and its use in cooking and/or production of cosmetics and drugs. Avocado is the second most produced fruit in the Distrito Federal, with production representing 62% of the total avocado sold in the Central de Abastecimento do Distrito Federal (CEASA-DF). Avocado is a perennial fruit that is highly affected by fungi that cause descendant death due to colonization of xylem vessels and death of plant tissues. Taxonomic studies on the etiology of the disease in other countries reveal several fungi associated with the disease and the occurrence of species according to the location and geographic region. However, it is observed that species of the Botryosphaeriaceae family are present in most observations of this symptomatological picture in plants, not only in avocado, but in other important fruit trees. The precise identification of the causal agents of avocado tree dieback and canker in Brazil has not yet been performed. Therefore, a polyphasic approach is essential for understanding the fungal species associated with the disease. For this, samplings will be carried out in the main avocado producing regions and symptomatic plants will be selected for fungal isolation. The identification of the pathogens responsible for the disease will be determined using morphological characteristics, DNA sequence and phylogenetic analyses. The elongation factor (TEF1α) will be used as a barcode for prior identification of the isolates. Subsequently, representative isolates of each species will be used for multilocus phylogenetic analysis. Pathogenicity tests will be carried out in plant and fruit using the mycelium disc methodology and evaluation after 60 days in plant and 7 days in fruit. For detection, primers will be developed to be tested with protocols based on loop-mediated isothermal amplification (LAMP) and multiplex qPCR seeking high specificity and sensitivity to enable the rapid and accurate identification of fungal species in production areas. In addition, we will test the detection protocols in pure culture of the fungus, leaves and stem of symptomatic seedlings. Therefore, this project aims to (i) precisely identify the fungi associated with dieback and canker in avocado trees, (ii) validate the LAMP technique for determining fungal species in the growing areas, and (ii) validate the multiplex qPCR method for quantification and simultaneous detection of fungi associated with mother plants and asymptomatic seedlings for the implementation of management strategies and direction of avocado improvement programs.

BANKING MEMBERS:
Externa à Instituição - KAMILA CAMARA CORREIA - UFCA
Externo à Instituição - JADSON DIOGO PEREIRA BEZERRA - UFG
Externa à Instituição - MAISA CIAMPI-GUILLARDI - USP
Externa ao Programa - 2222088 - ELIANE FERREIRA NORONHA
Externo ao Programa - 1703888 - HELSON MARIO MARTINS DO VALE
Presidente - 1351999 - LUIZ EDUARDO BASSAY BLUM