Selectivity of herbicides in native forest species of cerrado

Abstract

A aggravating problems in forest management is weed interference, which is a factor that modifies adaptation and reduces plant growth. The use of herbicides is an indispensable practice to mitigate these effects in reforestation areas. This study aimed to evaluate the selectivity of glyphosate and imazapyr in native plants of the Brazilian Cerrado, such as: Schinus terebinthifolia (Anacardiaceae), Peltophorum dubium (Fabaceae) and Handroanthus albus (Bignoniaceae). The trial was carried out in a greenhouse at Unit of Aquidauana/UEMS. Experimental design was completely randomized, with seven treatments and five replications. Selectivity of the herbicides in the seedlings of these species was evaluated at 7, 14, 21, 28 and 60 days after application (DAA) of the herbicides, by means of a percentage scale of notes, where 0% corresponds to no injury and 100% corresponds to plant death. At the same time, for the weed control evaluation, visual analysis was also performed at 7, 14, 21, 28 and 60 DAA of the herbicides, where 100% was considered plant death and 0% no injury to weed. Imazapyr herbicide, when applied in the initial post-emergence in its lower level, it is selective to the tree species, but in the other concentrations it can affect differently the survival of them. Glyphosate herbicide was the least selective to the tree species in its different concentrations, causing phytotoxic effects with changes in the seedlings morphology. The results of this study could help in the integrated management of weeds and contribute to the efficient herbicide use in planting forest species in the Cerrado.

Effect of pre-emergent graminicide herbicides on germination and early development of native species

“…This fact corroborates the results obtained in this research, since the highest dose of the herbicide isoxaflutole directly affected the early development of A. hasslerii seedlings. Polini et al (2018) evaluated the selectivity of herbicides in native forest species of the Cerrado biome and concluded that herbicide imazapyr, when applied at low doses in post-emergence, is selective for tree species Schinus terebinthifolia, Peltophorum dubium, and Handroanthus albus; at high concentrations, however, it may affect their survival differently. Tavares et al (2017) observed that the initial growth of Caryocar brasiliense plants was benefited from the application of 2,4-D subdoses for the variables leaf area, specific leaf area, and leaf area ratio.…”

Phytotoxicity of Herbicides in Seedlings of Sweet Passion Fruit

“…The herbicides glyphosate, imazapic, metsulfuron-methyl and glufosinate-ammonium reduced plant height gain (Paiva et al, 2015). According to Polini et al (2018) to application of herbicide glyphosate was the least selective to the tree species in its different concentrations, causing phytotoxic effects with changes in the seedlings morphology. The results of this study could help in the integrated management of weeds and contribute to the efficient herbicide use in planting forest species in the Cerrado.…”