studying the willingness to pay of wheat farmers to control weeds in different growth stages (case study of khorasan razavi)

abstract in this study, willingness to pay of 180 wheat farmers in khorasan razavi province to remove weeds in different options and different growth stages in 2008 through logarithmic regression was investigated. the results indicated that farmer's total annual income, being perennial of weeds and dummy variables percent of removing weeds in growth different stages, had positive and significant effect on farmers' willingness to pay. the most important variable, with a positive effect on farmers' willingness to pay to manage weeds in all three growth stages, is their annual income. the average farmer's willingness to pay to remove weeds in each of the existing status from germination to the generation growth stages trend had increased. according to the results, suggested taking into account the farmers' economical behavior for managing weeds in different growth steps in order to receive necessary management messages toward producing higher effective herbicides especially applicable in reproductive stage, willingness to pay for herbicides with different efficiencies in controlling weeds, specific look toward management of perennial weeds and combined controlling methods assuring above 70% controls.