Chemical control of bedstraw (Galium tricornutum Dandy) in wheat, barley, field peas, chickpeas and faba beans in southern Australia
Michael R. Moerkerk, Agriculture Victoria, Private Bag 260, Horsham, Victoria 3401, Australia.
Field experiments were carried out in Victoria between 1991 and 1994 to assess the efficacy of selective herbicides for the control of bedstraw in commercial field crops. Imazethapyr provided acceptable control of bedstraw in faba beans, field peas and chickpeas when applied pre-emergence, and in field peas post-emergence. Chickpea and faba beans were intolerant to imazethapyr applied post-emergence. Flumetsulam applied post-emergence gave effective control of bedstraw seed production in chickpeas and field peas. Faba beans were intolerant to flumetsulam. Bentazone, pyridate, diflufenican, simazine and metribuzin failed to give adequate control of bedstraw in pulse crops.
In wheat and barley, chemicals applied early post-emergence that provide acceptable crop safety and control bedstraw, include bromoxynil + MCPA ester + dicamba, flumetsulam, bromoxynil + diflufenican, fluroxypyr and amidosulfuron. Metsulfuron-methyl, metsulfuron-methyl + bromoxynil + MCPA ester, bromoxynil + MCPA ester and chlorsulfuron did not consistently control bedstraw in cereals. Bedstraw can be effectively controlled at later cereal growth stages with 2,4-D amine or fluroxypyr. Yield responses to chemical control of bedstraw were greater with herbicide applied earlier than later in the growing season.
The implication of chemical control options on potential herbicide resistance development in bedstraw is discussed.
Plant Protection Quarterly (1999) 14 (1) 24-29.