Abstract

PURICELLI, E.; VITTA, J.I.; SABBATINI, M.R.  and  ORIOLI, G.. Modeling population dynamics of Anoda cristata in a glyphosate-resistant soybean crop under different management systems. Agriscientia [online]. 2007, vol.24, n.1, pp.1-9. ISSN 1668-298X.

A computer simulation model was developed to describe Anoda cristata (L.) Schlecht seedbank dynamics in soybeans. The model considers different weed management strategies: absence of control, control with the recommended rate and with glyphosate at half the recommended rate, and two soybean row spacings (35 and 70 cm). The model was evaluated using data from previous experiments obtained for four consecutive years. The model accurately reproduced the seedbank dynamics. The seedbank decreased more in weed management strategies without seed production. In absence of control, the seedbank reached an equilibrium density. When seeds were produced every year, the model output was more sensitive to changes in the rate of predation; but without seed production, seed mortality was the most important process. Simulation demonstrated that long-term eradication may occur with continuous use of glyphosate at the recommended rate or with the combination of soybean at 35 cm between rows and glyphosate at half the recommended rate.

Keywords : Anoda cristata; Reduced glyphosate rates; Seedbanks; Weed population dynamics.

        · abstract in Spanish     · text in English     · English ( pdf )