Banca de DEFESA: YUJI ITO NUNES

Uma banca de DEFESA de MESTRADO foi cadastrada pelo programa.
STUDENT : YUJI ITO NUNES
DATE: 18/06/2025
TIME: 08:30
LOCAL: Sala 01 do Programa de Pós-graduação em Fitotecnia (PPGF)
TITLE:

Strategies for using Herbicides in Ecological Restoration in the Atlantic Forest Biome

KEY WORDS:

Chemical control, Forest restoration, Invasive species control

PAGES: 68
BIG AREA: Ciências Agrárias
AREA: Agronomia
SUBÁREA: Fitotecnia
SPECIALTY: Matologia
SUMMARY:

The Atlantic Forest biome is fragmented and surrounded by degraded pastures, predominantly colonized by invasive grasses of the genus Urochloa, which exert potential competition with native species. Planting seedlings represents a strategy for ecological restoration; however, managing these grasses poses a challenge. In this context, chemical control stands out as an effective and lower-cost alternative, promoting more suitable conditions for the establishment of forest species. Therefore, this project aimed to develop chemical weed control strategies and to evaluate the response of tree species to herbicides, in order to assist decision-making in managing competition during the establishment of forest stands in the Atlantic Forest. The experiment was conducted in a restoration area located in the municipality of Cachoeiras de Macacu, Rio de Janeiro. Weed control in the establishment of Atlantic Forest stands was evaluated using herbicides applied alone or in mixtures, and field selectivity was assessed for 20 tree species native to the Atlantic Forest biome. The strategies (treatments) used were: (T1) control with no herbicide; (E2) indaziflam applied as a directed spray (1st application) + glyphosate applied as a directed spray (2nd application); (E3) indaziflam applied over the top (1st application) + glyphosate applied as a directed spray (2nd application); (E4) indaziflam + haloxyfop mixture; (E5) haloxyfop-P-methyl applied on demand; (E6) glyphosate applied as a directed spray on demand. The strategies were arranged in a randomized complete block design, with four replications. Each experimental unit consisted of 5 planting rows with 20 planting holes per row, totaling 100 planting holes per experimental unit, using 20 tree species native to the Atlantic Forest. At 30, 60, 90, and 120 days after application (DAA) of each treatment, evaluations of weed control and phytotoxicity on forest species were carried out. At 6, 12, and 14 months after transplanting, height, stem diameter, and phytosociological inventory were assessed. At 14 months, crown length was evaluated to calculate ground cover.E3 showed the best pre-emergence weed control in all evaluations, while in post-emergence, E6 showed the best control. At 120 DAA, only strategy 4 showed phytotoxicity above the concerning threshold, indicating possible incompatibility. Chromolaena maximiliani was the species with the highest IVI (Importance Value Index) in the control treatment and in strategies E4 and E5. In strategy 6, the species with the highest IVI were Fimbristylis dichotoma and Cyperus rotundus, which are not considered problematic for restoration. The highest growth at 14 months in terms of shoot height, crown area, and ground-level diameter (averaged across the 20 tree species) was observed in strategy 6. For ground cover at 14 months, strategies 3 and 6 had coverage rates above 30%. When analyzing the number of regenerating individuals, strategy 5 had the highest values, while strategy 6 had the lowest. It is recommended to use indaziflam in pre-emergence applied over the top combined with glyphosate applied on demand for localized control. For post-emergence management, the recommended strategy is directed spray application of glyphosate.

COMMITTEE MEMBERS:
Presidente - 1905333 - AROLDO FERREIRA LOPES MACHADO
Externo ao Programa - 3155350 - RODOLFO CESAR REAL DE ABREU - UFRRJExterno à Instituição - LUIZ FERNANDO DUARTE DE MORAES - EMBRAPA