Influence of different herbicide application methods on weed control of marigold (Tagetes erecta L.) nursery

A field experiment was conducted at College of Aburaihan, University of Tehran, Iran in 2007 to evaluate the herbicides efficacy in a marigold nursery to control weeds including annual flowers. Experimental design was a RCBD with total 12 treatments replicated four times. Treatments were trifluralin preplant incorporated at two and three Li/ha, trifluralin preplant non incorporated at two and three Li/ha, oxyfluorfen preplant at two and three Li/ha, oxyfluorfen postemergence at two and three Li/ha and cholorothol-dimethyl preplant at 10 Kg/ha, two-times hand weeding, weedy and weed free treatments were also included as control. Application of oxyfluorfen preplant and trifluralin preplant at both rates of two and three Li/ha controlled weeds by 70 percent. This treatment had no phytotoxic effects on marigolds and did not reduce their yields either. Among applied herbicides, application of non-soil incorporated trifluralin treatment compared with treatment of the same soil incorporated with herbicides, due to easier application, indicated its preference and also had no phytotoxic effects on marigold.