Weed control in potatoes on the Atherton Tableland, Queensland

Abstract

Three experiments were conducted in winter and summer over two years testing chemicals and cultivation for weed control in potatoes on the Atherton Tableland, Queensland. In all trials cultivation effectively prevented weeds from causing yield reductions. Under dry conditions, cultivation was more effective than chemicals in controlling weeds. Under wet conditions chemicals controlled weeds better than cultivation. Under cool wet conditions linuron used at either 2.24 kg a.i. ha pre-emergence or at 1 .12 kg a.i. ha-1 at first emergence of the potatoes controlled weeds very well without reducing tuber yield. Under hot wet conditions linuron was less effective, probably because of more rapid breakdown of the chemical. In hot wet weather terbutryne plus sebuthylazine applied at 1.68 or 2.24 kg a.i, ha-1, or metribuzin applied at 0.78 kg a.i. ha -1 at first emergence of the potatoes controlled weeds better than linuron without reducing potato yields.