Herbicide resistance has been attracting the attention of researchers
in many countries as it hinders the cultivation of different main crops. Many
grass weeds belonging to Lolium and Avena species specially rigid
ryegrass (Lolium rigidum L.) and wild oat (Avena fatua L.) are
considered serious weed species in different crops, mainly cereals, allover the
world, i.e. Africa, Asia, Europe, North and South America and Australia.
Biotypes of resistant populations of both species appeared at many locations
especially toward the two chemical herbicidal groups aryloxyphenoxypropanoate
(APP) and cyclohexanedione (CHD) that are commonly used for the control of
these weeds. These two chemical groups are known to act as acetyl coenzyme A
carboxylase (ACCase) inhibitors. The materials digested here represent an
overall projection about the herbicide resistance in grass weeds especially
rigid ryegrass and wild oat as
most important common resistant weed species. That includes: herbicide
resistant wild oat globally, the ACCase inhibitors toward resistant weeds by
species and country and the situation of herbicide resistance globally
including Egypt. Discussion is extended, in a common direction, to the
chemistry and mode of action of the two mentioned groups, mechanisms endowing selectivity,
evolution and development of resistance, mechanism of resistance and management
approaches of resistant populations, on the light of the most recent
literature. Presentation is also directed toward detecting herbicide
resistance, the cost of herbicide resistance, the present situation of two
common grasses in Egypt, i.e. wild oat (Avena fatua) and Italian
ryegrass (L. multiflorum) management and research conducted in Assiut
area.