Dinâmica de plantas daninhas após aplicação de oxadiazon com simulação de lâminas d’água e incorporação de material orgânico

Abstract

RESUMOObjetivou-se, neste trabalho, determinar o efeito do oxadiazon no comportamento da comunidade de plantas daninhas em diferentes momentos de aplicação de lâminas d'água e incorporação de material orgânico. Utilizou-se o delineamento em blocos casualizados com tratamentos dispostos em esquema fatorial 5 x 2, com 4 repetições. Os tratamentos foram constituídos pela combinação da incorporação (8 t ha -1 ) ou não de material orgânico no solo e do momento de aplicação de lâminas d'água (0; 10 mm antes; 10 mm depois e sequencial de 10 mm antes e depois da aplicação do oxadiazon); além da testemunha (0 mm e 0 g ha -1 de oxadiazon). Foram obtidas a densidade relativa, a frequência relativa, a abundância relativa, o índice de valor de importância (IVI) e o índice de similaridade (IS) da flora de plantas daninhas. Não houve interação significativa entre o material orgânico e as lâminas d'água. A espécie Cyperus rotundus apresentou maior IVI, independente do tratamento avaliado, seguidas da Urochloa decumbens, Galinsoga parviflora, Bidens pilosa e Melampodium perfoliatum. A maior similaridade (IS = 0,75) foi observada entre o tratamento que recebeu a aplicação de 10 mm de lâmina d'água antes associado com o de 10 mm depois de aplicação do oxadiazon.Palavras-chave: herbicida neutro, irrigação, matéria orgânica, similaridade Dynamics of weeds after application of oxadiazon with simulated water depths and incorporation of organic material ABSTRACTThe objective of this work was to determine the effect of oxadiazon in the behavior of the weed community under different moments of application of water depths and incorporation of organic material. A randomized block design was used with treatments arranged in a factorial 5 x 2 with four replications. The treatments consisted of combination of with or without incorporation (8 t ha -1) of organic material in the soil and the moments of application of water depths (0, before 10 mm, after 10 mm, and sequential 10 mm before and after application of oxadiazon), and the control (0 mm water and 0 g ha -1 of oxadiazon). Relative density, relative frequency, relative abundance, importance value index (IVI) and similarity index (SI) of the weed flora were obtained. No significant interaction between the organic material and water depths was observed. Cyperus rotundus showed higher IVI, regardless of the experimental treatment, followed by Urochloa decumbens, Galinsoga parviflora, Bidens pilosa and Melampodium perfoliatum. The highest similarity (SI = 0.75) was observed between treatments with the application of 10 mm water depth before associated with the 10 mm after the application of oxadiazon.

Interference of the Association Oxyfluorfen + Flumioxazin and the Addition of Mineral Oil on a Phytosociological Survey

“…These studies allow determining the importance degree of these plants in specific areas through phytosociological indices such as frequency, density, and abundance (Concenço et al, 2013). In order to understand the applicability of these surveys to weed science, as well as their validity, it is necessary to choose appropriate and ecologically based methods, since cultivated areas present a relatively distinct group of selection factors, when compared to natural environments (Gomes et al, 2010;Mendes et al, 2014). Therefore, the goal of this study was to evaluate the interference of mineral oil associated with oxyfluorfen and flumioxazin in the phytosociological survey of weeds.…”

Fitossociologia de plantas daninhas em cultivos de feijão sobre diferentes manejos de herbicidas

“…Studies have been conducted using phytosociological indices, which allow an analysis of the impact that management systems and cultural practices have on growth dynamics and dominance of invasive weeds communities in agricultural systems (Oliveira and Freitas, 2008). Several studies have already demonstrated the impacts of herbicides on weeds dynamics (Malik et al, 2007;Reis et al, 2013;Mendes et al, 2014). However, there are little information on the effects of the application technology on the weed flora.…”