The selective chemical control of Wimmera ryegrass in wheat with di-allate and tri-allate

Abstract

Two herbicides, di-allate and tri-allate, were compared for the pre-emergence control of Wimmera ryegrass (Lolium rigidum) in wheat at three different locations in the Victorian wheatgrowing areas. Both herbicides significantly reduced ryegrass populations in the crop, but di-allate was consistently more effective than tri-allate. Grain yields were generally enhanced by spraying, but 1.12 kg a.i. per hectare of either material sometimes caused crop damage when applied before sowing. On an economic basis, di-allate at 0.56 kg a.i. per hectare was superior to all other treatments whether applied just before or just after sowing.