Banca de DEFESA: AMANDA DOS SANTOS SOUZA
Uma banca de DEFESA de DOUTORADO foi cadastrada pelo programa.STUDENT : AMANDA DOS SANTOS SOUZA
DATE: 23/06/2022
TIME: 13:00
LOCAL: Webconferência
TITLE:
Anatomical changes and in the absorption and translocation of herbicides as a resistance mechanism in Conyza sumatrensis
KEY WORDS:
anatomical characterization, herbicide metabolism, herbicide transport
PAGES: 84
BIG AREA: Ciências Agrárias
AREA: Agronomia
SUBÁREA: Fitotecnia
SPECIALTY: Matologia
SUMMARY:
Management of the resistant biotype and the elucidation of the resistance mechanisms are extremely important for agricultural systems. The objective of the research was to determine if the resistance mechanism is the differential anatomy, reduced absorption and translocation and metabolization of herbicides in Conyza sumatrensis biotype and in addition to propose better management for controlling this biotype. CHAPTER I: Conyza sumatrensis biotypes were evaluated for anatomical differentiation after the application of the herbicides 2,4-D (1005g a.e ha-1). Two experiments were carried out: 1Light microscopy, the leaves of resistant and susceptible were collected and analyzed 15 and 30 MAA. 2Scanning electron microscopy, the resistant and susceptible leaves were collected 30 MAA and 3HAA. CHAPTER II: Conyza sumatrensis biotypes were evaluated for absorption and translocation, after the application of the herbicide glyphosate (720g a.e ha-1) and saflufenacil (70g a.i. ha-1). Two experiments were carried out: 1 14C-glyphosate at 24,48,72,96 and 120 HAA and 2 14C-saflufenacil at 6, 12, 24, 48 and 72 HAA were evaluated for absorption and translocation. CHAPTER III: Absorption and translocation were evaluated in Conyza sumatrensis after the 2,4-D (1005 g e. a ha-1) three experiments were carried out: 1 14C-2,4-D absorption and translocation was evaluated at 3, 12, 24, 48 and 96 HAA. 2 14C-2,4-D metabolism was evaluated at 3, 12, 24, 48 and 96 HAA. 3Malathion effect on 2,4-D resistance were evaluated at 7, 14 and 35DAA. CHAPTER IV: Management strategies in the control of resistant Conyza sumatrensis were evaluated. Two experiments were carried out: 1The experiment was conducted in a greenhouse. Glyphosate herbicides (720g ia ha-1); 2,4-D (1005g ai ha-1); triclopyr (720g ai ha-1); halauxifen-methyl+diclosulam (5.17+25.5g ia ha-1) and dicamba (480g ia ha-1); isolates were applied and auxinics with glyphosate (720g ai ha-1), the same with addition of saflufenacil (35g ia ha-1) or sequential ammonium glufosinate (400g ia ha-1) applied 10 days after the first application (DAPA). At 4 and 48 hours, 10, 15 and 35 DAPA, visual control analysis was performed and at 35 DAPA, MSPA. 2The experiment was conducted in the field. 2,4-D herbicides (1005g ai ha-1); triclopyr (720 g ai ha-1); halauxifen-methyl + diclosulam (6.5+31.8g ia ha-1) and dicamba (384g ia ha-1) in association with glyphosate (1200g ea ha-1); the same associations with addition of saflufenacil (35g ai ha-1) or sequential ammonium glufosinate (400g ai ha-1) at 8 DAPA. At 14 and 50 DAPA, visual control analyzes were performed. CHAPTER I: There was a difference between the biotypes after application, it was possible to observe anatomical differences in the resistant biotype after application of the herbicide 2,4-D. CHAPTER II: There was no difference between the biotypes in the absorption and translocation of the herbicide glyphosate and saflufenacil. CHAPTER III: the reduced translocation of the herbicide 2,4-D is one of the resistance mechanisms for the resistant biotype of Conyza sumatrensis. CHAPTER IV: The application in mixture with the herbicide saflufenacil or sequential with the herbicide glufosinate proved to be excellent strategies to control the resistant biotype of Conyza sumatrensis.
BANKING MEMBERS:
Presidente - 2466219 - CAMILA FERREIRA DE PINHO
Interno - 1905333 - AROLDO FERREIRA LOPES MACHADO
Externo ao Programa - 3058137 - LUIZ RICARDO DOS SANTOS TOZIN
Externa à Instituição - CATARINE MARKUS - UFRGS
Externo à Instituição - ANDERSON LUIS NUNES - IFRS