GESTINF - A DECISION-MODEL FOR POSTEMERGENCE WEED MANAGEMENT IN SOYBEAN (GLYCINE-MAX (L) MERR)

The selection of the best weed control option can be improved using de cision-support systems considering the different factors affecting the efficacy (weed species, growth stage, climatic conditions) and the ec onomics of the treatments. An interactive microcomputer program called GESTINF has been developed to assist in the selection of weed control options in soybean and winter wheat. Using observed weed densities, c rop weed-free yield and grain price as input data, the program estimat es potential crop damage from multispecies weed complexes and ranks th e different weed control options according to expected net returns. Th e program also gives estimates of yield loss due to weeds surviving th e treatment and an environmental index indicating how hazardous the tr eatment is for the water-table, thus allowing a selection of treatment s both on an economic and an environmental basis. The system has been tested for 4 years in different locations of north-eastern Italy. The system forecasted the yield losses observed in the field fairly accura tely and proved capable of selecting appropriate interventions on the basis of type of flora and weed growth stage. (C) 1997 Elsevier Scienc e Ltd.