SciELO - Scientific Electronic Library Online

vol.27 issue1Fomesafen absorption site as a mechanism of resistance in an Euphorbia heterophylla biotype resistant to PROTOX inhibitorsThe effect of adjuvants on glyphosate absorption and translocation in water hyacinth (Eichhornia crassipes) author indexsubject indexarticles search
Home Pagealphabetic serial listing  

Services on Demand




Related links


Planta Daninha

Print version ISSN 0100-8358On-line version ISSN 1806-9681


GUIMARAES, A.A. et al. Chemical composition of the epicuticular wax of Italian ryegrass biotypes resistant and susceptible to glyphosate. Planta daninha [online]. 2009, vol.27, n.1, pp.149-154. ISSN 0100-8358.

The objective of this work was to determine the chemical composition of epicuticular wax of Italian ryegrass (Lolium multiflorum) biotypes resistant and susceptible to glyphosate, searching for relationships between their characteristics and the resistance of the biotypes to the product. The epicuticular wax was extracted and quantified, and its constituents analyzed by gas chromatography, coupled to mass spectrometer (CG-EM). To determine the chemical composition, leaf blade samples were obtained 30 days after plant emergence, the first leaf being collected with totally visible ligule. The amount of epicuticular wax did not differ between the biotypes. Alcohols are the most abundant among the compounds constituting the epiticular wax, represented by only one compound, hexacosan-1-ol (46.80% in the resistant biotype and 52.20% in the susceptible). When comparing the polarity of the epicuticular wax of the Italian ryegrass biotypes, it was verified that both in the resistant and susceptible biotypes, the epicuticular wax presented more than 50% of polar compounds (alcohols and aldehydes) in its constitution, with that value being equal to 69.80% in the resistant biotype and 64.94% in the susceptible. Thus, it can be stated that small differences exist in the epicuticular wax of Italian ryegrass biotypes resistant and susceptible to glyphosate. The resistant biotype presented a slightly higher polarity degree than the susceptible biotype but such difference cannot be considered sufficiently relevant to determine a greater or smaller tolerance of either biotype to glyphosate.

Keywords : resistance; chromatography; Lolium multiflorum; transgeny.

        · abstract in Portuguese     · text in Portuguese     · Portuguese ( pdf )


Creative Commons License All the contents of this journal, except where otherwise noted, is licensed under a Creative Commons Attribution License