Abstract
Background: One of the problems encountered in agriculture which affects most
crops, is weed control. Herbicide use has created environmental problems,
toxicity and resistance of some species. An alternative is the use of essential
oils, which can produce allelopathic effects causing inhibition of germination
and growth of weeds. Methods: The trial was set up in a greenhouse at an
Esperanza farm (Fusagasuga, Colombia), consisting of placing soil in trays and
apply uniform irrigation with a completely randomized design with nine
treatments with five replications. Treatments included a Lippia
alba extracts in three concentrations of 100, 300 and 500 mg/L, water,
water plus coadjuvant and a commercial herbicide as control. Germination rates
of different groups of weeds were valued and control rates were determined. Results
and discussion: For dicotyledonous treatments Baccharis trinervis
(100 mg/L) and L. alba (500 mg/L) showed the best values controls 59.9
and 54.9 % against uncontrolled treatment. A second group includes all
treatments of L. alba with values showing a regular control against
uncontrolled treatment. The herbicide atrazine showed a percentage of control
to 37.3%) is a poor control as
measured for scale Association Latinoamerican weed management (ALAM). To treat
grass weeds with atrazine worth 76.6%, within the range that ALAM is a good
control. Baccharis s trinervis (500 mg/L) with 59.8% and B.
trinervis (300 mg/L) with 50.9% in the scale that appears as a regular ALAM
control. For sedges, weeds show that better controls corresponded to L. alba
(500 mg/L) and the commercial herbicide with values of 59.7 and 54.0%,
respectively. Continue treatments B. trinervis (100 mg/L and 300 mg/L)
controls 50.7 and 43.6%. Controls obtained are largely due to the metabolites
present as sesquiterpenes Essential
Oils (EO) as acting as inhibitors of seed germination. Conclusions: The
E.O of B. trinervis and L. alba showed better control of
dicotyledonous weeds and sedges that the herbicide. Grass weeds in herbicide
outperformed the other treatments but showed percentages of acceptable
control.
Keywords: Baccharis trinervis, Lippia alba, germination, Percent control, escale ALAM