title: Low resistance against novel 2-benzylamino-1,3,5-triazine herbicides in atrazine-resistant Chenopodium album plants.
abstract: The effects of nine novel 2-benzylamino-1,3,5-triazines on photosynthetic reactions were measured in thylakoids isolated from wild-type and atrazine-resistant plants of Chenopodium album. The resistant plants have a mutation of serine for glycine at position 264 of the D1 protein. The measurement of oxygen evolution and chlorophyll a fluorescence induction indicated a 2-4-fold stronger inhibition by the 6-trifluoromethyl analogues of Photosystem II-dependent electron flow than atrazine. Analogues having a 6-methyl-, 6-monofluoromethyl or 6-difluoromethyl substitution were weak inhibitors, indicating that the 6-trifluoro group is very important for strong inhibition. All the nine novel 2-benzylamino-1,3,5-triazines were almost as active in wild-type as in atrazine-resistant thylakoids, indicating that the benzylamino substitution may be important for the lack of resistance in the atrazine-resistant plants.
authors.affiliation: Graduate School of Agricultural Science, Tamagawa University, Tamagawa Gakuen, Machida-shi, Tokyo, 194-8610, Japan.
authors.forename: H
authors.initials: H
authors.lastname: Kohno
authors.forename: A
authors.initials: A
authors.lastname: Ohki
authors.forename: S
authors.initials: S
authors.lastname: Ohki
authors.forename: K
authors.initials: K
authors.lastname: Koizumi
authors.forename: M E
authors.initials: ME
authors.lastname: Van den Noort
authors.forename: G C
authors.initials: GC
authors.lastname: Rodrigues
authors.forename: J J
authors.initials: JJ
authors.lastname: Van Rensen
authors.forename: K
authors.initials: K
authors.lastname: Wakabayashi