Slender foxtail

In other weed biotypes, resistance to triazine herbicides is likely conferred by rapid metabolism of the herbicides to inactive compounds. A chlorotoluron-resistant biotype of blackgrass (slender foxtail) was cross-resistant to various other groups of herbicides, including triazines (Kemp et al., 1990). The mechanism of chlorotoluron resistance was Cyt P450-based enhanced oxidative metabolism through /V-demethylation and ring-methyl hydroxylation (Moss and Cussans, 1991). Consequently, it is likely that resistance to triazines in this blackgrass biotype is also due to enhanced herbicide detoxification. 

Blackgrass (also known as slender foxtail) and wild oat are important arable weeds as are both Italian and peremrial ryegrasses, particularly in situations where they have been allowed to set seed. Awned catrary grass is an increasing problem on arable land in south-east England. 

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