Banca de QUALIFICAÇÃO: ANTHONY CORTES GOMES

Uma banca de QUALIFICAÇÃO de DOUTORADO foi cadastrada pelo programa.
STUDENT : ANTHONY CORTES GOMES
DATE: 12/05/2023
TIME: 13:30
LOCAL: Webconferência
TITLE:

ELUCIDATION OF THE GENETIC AND MOLECULAR BASIS OF 2,4-D HERBICIDE RESISTANT Conyza sumatrensis

KEY WORDS:

Resistance, horseweed, segregation, gene expression.

PAGES: 20
BIG AREA: Ciências Agrárias
AREA: Agronomia
SUBÁREA: Fitotecnia
SPECIALTY: Matologia
SUMMARY:

Several biotypes of Conyza sumatrensis, popularly known as buva, have shown resistance to herbicides over the years. Consequently, the inefficient control and competition exerted by this species affect the most diverse fields of agricultural production. Therefore, it is essential to know the genetic and molecular bases that confer resistance to these biotypes. Knowing how many and which genes are responsible for resistance provides the possibility to monitor, predict and circumvent resistance of Conyza sumatrensis to herbicides. In view of this condition, the objective of the present study is to identify the type of genetic inheritance as well as any difference in gene expression between susceptible and resistant biotypes that confer resistance to the 2,4-D herbicide. The Conyza sumatrensis biotype that will be used shows confirmed resistance to the herbicides 2,4-D, saflufenacil, glyphosate, diuron, diquat and paraquat. For genetic inheritance assays, F1 progeny will be derived from parental crosses between resistant (R) and susceptible (S) biotypes, including two S♂ x R♀ crosses and three R♂ x S♀ crosses. Then, all F1 progeny will be treated with 1005 g ae ha-1 of 2,4-D when the plants reach 10 to 12 cm in height. The plants will then be compared with the parent R and S and visually classified as surviving (resistant) or dead (susceptible) at 45 days after herbicide application (DAA). Survivors of F1 progeny will be self-pollinated to produce F2 progeny. Doses 0, 0.25x, 0.5x, 1x and 2x of 2,4-D will be applied to the F2 progeny and later they will also be classified as survivors and killed at 21 DAA, where again the survivors will be self-pollinated to generate the F3 progeny. The F3 progeny plants will receive the application of 2,4-D herbicides at doses of 0.5x and 1x and will be compared as previously described. At the end, the chi-square (χ2) fit test will be performed to compare survival and identify the dominance model. From the surviving genotypes of the F3 progeny, analyzes will be performed in order to identify the difference in gene expression. For this purpose, Genotyping by Sequencing (GBS) and Gene Expression Analysis (RNA-seq) will be performed according to a pre-established methodology. Data from both analyzes will be evaluated with statistical bioinformatics software to validate the results found.

COMMITTEE MEMBERS:
Presidente - 2466219 - CAMILA FERREIRA DE PINHO
Interno - 1905333 - AROLDO FERREIRA LOPES MACHADO
Externa à Instituição - CRISTINA MOLL HUTHER - UFF