Herbicide selectivity in the early development of Alexander palm and peach palm

Abstract

Herbicides are an efficient weed-control method, and herbicide selectivity with regard to palm species is an important subject of agricultural research. Owing to a lack of studies in the literature regarding the use of herbicides on palm trees, especially during the early stages of growth, the present study aimed to evaluate the selectivity of some herbicides during the early development of Alexander palm (Archontophoenix alexandrae) and peach palm (Bactris gasipaes) seedlings. The study was conducted in two seasons in a completely randomized design with eight treatments and four repetitions. The herbicide treatments and dosages (g i.a. ha-1), were as follows: fluazifop-p-butyl (93.8), sethoxydim (184.0), quizalofop-p-ethyl (75.0) clethodim + fenoxaprop-p-ethyl (50.0 + 50.0), fomesafen (225.0), lactofen (168.0), and nicosulfuron (50.0), and a no-herbicide control was included. The seedlings of both types of trees were transplanted into 3.1-L plastic containers. In the first study, herbicide was applied to Alexander palm seedlings of 25–30 cm in height. In the second study, herbicide was applied to Alexander palm seedlings of 30–40 cm in height. Herbicide was applied to peach palm tree seedlings of 40–55 cm in height in both studies. In peach palms only, the herbicides caused slight visible damage during early development. Collectively, the results suggested that all herbicides used are selective and can be used on peach palms during the various stages of development when there are one to four leaves. For Alexander palms, fluazifop-p-butyl, quizalofop-p-ethyl, and lactofen were the only herbicides that did not affect early development during the stages when the plant had one to four leaves.