Banca de DEFESA: Angelica Rodrigues Alves

Uma banca de DEFESA de MESTRADO foi cadastrada pelo programa.
STUDENT : Angelica Rodrigues Alves
DATE: 05/09/2022
TIME: 14:00
LOCAL: Videoconferência
TITLE:

Diversity and development of a detection PCR protocol for Xanthomonas euvesicatoria pv. allii

KEY WORDS:

Allium cepa, BOX-PCR, MLSA, primers

PAGES: 70
BIG AREA: Ciências Biológicas
AREA: Biologia Geral
SUMMARY:

Onion (Allium cepa L.) is an important vegetable cultivated since ancient times and distributed worldwide. It is the third most cultivated vegetable, after potatoes and tomatoes. An outbreak of onion bacterial blight occurred in 2018, and since then, has been threatening onion quality and productivity in the Brazilian Cerrado within the states of Goiás, Minas Gerais and Distrito Federal. Samples were collected isolates identified as being Xanthomonas euvesicatoria pv. allii (Xea). To increase knowledge about the pathogen, the objective of this work was to structure a new collection of isolates, identify, characterize, and develop a new PCR detection protocol for Xea. The 2021 isolate collection had its genus confirmed by the XgumD F7/R7 primers and the variability by the BOX-PCR molecular marker technique. Haplotypes were selected for sequencing four genomic regions for multilocus sequence analysis. For the development of a detection protocol, six genomes available in the GenBank of Xea were reannotated and then, by comparative genomics, we searched for genes present among all isolates and absent for other species and pathovars. For the design of the primers the sequences of the exclusive genes were used in the software NEB LAMP Primer Design Tool. The synthesized primers were evaluated for the amplification capacity of Xea isolates, sensitivity, and specificity with onion leaf microbiota. All isolates were identified as belonging to the genus Xanthomonas and by BOX-PCR it was possible to identify the presence of four haplotypes in addition to the six haplotypes from the original collection. By multilocus sequence analysis, the clustering of the new isolates with the originals of 2018/2019 with high values of posterior probability was observed, while only the isolate A-2021-01 clustered in a more distant clade with isolates of the pathovar alfalfae. Only the 5038_ID9 primers were able to amplify all haplotypes only with the expected 200 pb fragment and amplification sensitivity of concentrations greater than 50 pg. None of the microbiota isolates were amplified with these primers.

BANKING MEMBERS:
Externo à Instituição - EDIVANIO RODRIGUES DE ARAUJO
Interna - 2215041 - MARISA A DA S VELLOSO FERREIRA
Presidente - 3051226 - MAURICIO ROSSATO
Interna - 3117540 - THAIS RIBEIRO SANTIAGO