Table I.
Herbicide sensitivity of and mutant chloroplastic ACCase alleles detected in seedlings from four field and two purified black-grass populations
| Population
|
Mutant ACCase Allele(s) Detected
|
CHD Herbicides
|
APP Herbicides
|
||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|
| Cycloxydim
|
Clethodim
|
Fenoxaprop
|
Clodinafop
|
Haloxyfop
|
|||||||
| Ra | Sa | R | S | R | S | R | S | R | S | ||
| 00-017b | None | 0 | 50 | 0 | 50 | 0 | 50 | 0 | 50 | 0 | 50 |
| 00-016 | None | 0 | 20 | 0 | 18 | 12 | 7 | 0 | 21 | 0 | 17 |
| Cys-2,027c | 0 | 30 | 0 | 32 | 31 | 0 | 29 | 0 | 33 | 0 | |
| P-value (Cys-2,027)d | 1.0 | 1.0 | 5.10−4 | 0.0 | 0.0 | ||||||
| 00-049 | None | 0 | 3 | 0 | 4 | 0 | 2 | 1 | 1 | 0 | 3 |
| Leu-1,781c | 32 | 0 | 0 | 30 | 32 | 0 | 18 | 13 | 0 | 33 | |
| Gly-2,078c | 4 | 0 | 6 | 0 | 7 | 0 | 5 | 0 | 5 | 0 | |
| Leu-1,781 + Gly-2,078f | 11 | 0 | 10 | 0 | 9 | 0 | 12 | 0 | 9 | 0 | |
| P-value (Gly-2,078)d | 0.0286 | 2.10−4 | 0.0278 | 0.1053 | 0.0015 | ||||||
| 00-099 | None | 0 | 5 | 0 | 4 | 0 | 6 | 0 | 6 | 0 | 5 |
| Leu-1,781c | 1 | 0 | 0 | 2 | 1 | 0 | 0 | 0 | 0 | 2 | |
| Asn-2,041c | 0 | 5 | 0 | 6 | 4 | 0 | 6 | 0 | 6 | 0 | |
| Ala-2,096c | 0 | 29 | 0 | 31 | 28 + 3e | 0 | 28 + 2e | 0 | 26 + 2e | 0 | |
| Leu-1,781 + Asn-2,041f | 1 | 0 | 0 | 0 | 0 | 0 | 1 | 0 | 1 | 0 | |
| Leu-1,781 + Ala-2,096f | 2 | 0 | 0 | 1 | 1 | 0 | 2 | 0 | 1 | 0 | |
| Asn-2,041 + Ala-2,096f | 0 | 7 | 0 | 6 | 7 | 0 | 5 | 0 | 7 | 0 | |
| P-value (Ala-2,096)d | 1.0 | 1.0 | 0.0 | 0.0 | 0.0 | ||||||
| Cys-2,027-F1b,g | Cys-2,027h | 0 | 50 | 0 | 50 | 50 | 0 | 50 | 0 | 50 | 0 |
| Gly-2,078-F1b,g | Gly-2,078h | 50 | 0 | 50 | 0 | 50 | 0 | 50 | 0 | 50 | 0 |
| Ala-2,096-F1b,g | Ala-2,096h | 0 | 50 | 0 | 50 | 50 | 0 | 50 | 0 | 50 | 0 |
a
S, Sensitive; R, resistant.
b
Population used for ACCase enzyme assay.
c
One or two allele(s) mutated at the same codon were detected.
d
Fisher's exact test for the association of the presence of the mutant ACCase allele with resistance to each herbicide.
e
Resistant plants with a green first leaf of less than 1 cm in length.
f
A single copy of each mutant allele was detected.
g
Purified population (see “Materials and Methods”).
h
Two alleles mutated at the same codon were detected.