Beckmannia syzigachne (Steud.) Fernald is one of the
main grass weeds severely harming wheat (
Triticum aestivum
L.) production in rice-wheat areas in China.
Fenoxaprop-
p-ethyl is the main herbicide used to
selectively control grass weed in China.
Beckmannia
syzigachne has evolved resistance to fenoxaprop-
p-ethyl
due to continuous application. To investigate fenoxaprop-
p-
ethyl resistant level and mechanism in B.
syzigachne
in a portion of the rice-wheat area in China, samples
from 31 field populations were collected and treated with
fenoxaprop-
p-ethyl. The results show that 10 of the 31
tested field populations evolved a high level of resistance
to fenoxaprop-
p-ethyl. A portion of the acetyl-coenzyme
A carboxylase (
ACCase) gene was amplified, sequenced
and aligned. The known Ile-1781-Leu, Ile-1781-Val, Ile-
2041-Asn, Asp-2078-Gly and Gly-2096-Ala mutations
were identified in five resistant populations. None of the
known resistant substitutions was identified in the other
five resistant populations, which means the resistance to
fenoxaprop-
p-ethyl in these populations is likely endowed
by non-target-site resistance mechanism.
