Root exudation of imazapyr by eucalypt, cultivated in soil

Planta Daninha

Universidade Federal de Viçosa, Viçosa¹  Silva, C.M.M.¹  Ferreira, L.R.¹  Miranda, G.V.¹  Ferreira, F.A.¹  Universidade Federal do Norte Fluminense, Campos dos Goytacazes¹ 

关键词: Chopper;    Eucalyptus grandis;    bioindicators;    interference;    exudates.;   

DOI  :  10.1590/S0100-83582004000100014

学科分类：农业科学（综合）

来源: Sociedade Brasileira da Ciencia das Plantas Daninhas (S B C P D) / Brazilian Society of Herb Science

【 摘 要 】

Imazapyr has been used to control stump sprouting in stand of Eucalyptus plantations, where herbicide is applied to the tree trunk before cutting. The herbicide is applied exclusively on the stump to be killed, but little is known about the final fate of the molecule. Imazapyr exudation via roots of eucalypt grown in soil as the substrate was evaluated under greenhouse conditions. Different herbicide doses (0.000, 0.375, 0.750, 1.125, 1.500, and 3.000 kg ha-1 a.i.) were applied on the aerial parts of 8-month-old Eucalyptus grandis clonal seedlings, cultivated in pots with 18.0 dm3 of soil. Forty days after this treatment, the eucalypt plants were cut and a lateral opening in the containers was made and the plants inclined 90o, with plants sensitive to herbicide presence (sorghum and cucumber) sown into the openings along the exposed soil surface. After 15-day sowing, toxicity symptoms on the shoots as well as the shoot and root system dry biomass of the bio-indicators were evaluated. The results suggest that eucalypt roots do exude imazapyr, and/or its metabolites, at concentrations high enough to cause toxicity to the bio-indicators. Toxicity effects were observed in all plants sown along the exposed soil profile of the container, with higher intensity at higher doses.

【 授权许可】

Unknown