title: Structural requirements of strigolactones for germination induction of Striga gesnerioides seeds.
abstract: Strigolactones are highly potent germination stimulants for seeds of the parasitic weeds Striga and Orobanche spp. 4-Hydroxy-GR24 and 4-acetoxy-GR24 were prepared and their abilities to induce seed germination of Striga gesnerioides evaluated. Optically active (8bR,2'R)-isomers induced germination, although the racemic diastereomers were inactive. In contrast, the stereoisomer of GR24 with the same configuration induced negligible germination. Some stereoisomers of GR24 and its analogues acted as effective antagonists for induction of seed germination by cowpea root exudates. These results suggest that both an oxygenated substituent at C-4 and the configuration of the tricyclic lactone and the D-ring are essential structural requirements for induction of germination in S. gesnerioides seeds.
authors.affiliation: Graduate School of Agricultural Science, Kobe University, Rokkodai, Nada, Kobe 657-8501, Japan.
authors.forename: Kotomi
authors.initials: K
authors.lastname: Ueno
authors.forename: Mami
authors.initials: M
authors.lastname: Fujiwara
authors.forename: Saki
authors.initials: S
authors.lastname: Nomura
authors.forename: Masaharu
authors.initials: M
authors.lastname: Mizutani
authors.forename: Mitsuru
authors.initials: M
authors.lastname: Sasaki
authors.forename: Hirosato
authors.initials: H
authors.lastname: Takikawa
authors.forename: Yukihiro
authors.initials: Y
authors.lastname: Sugimoto
mesh_terms: D018525:Germination / Q000187:drug effects*; D007783:Lactones / Q000737:chemistry* / Q000494:pharmacology; D012639:Seeds / Q000187:drug effects / Q000254:growth & development*; D013237:Stereoisomerism; D034362:Striga; D013329:Structure-Activity Relationship
chemical_list: C507382:GR24 compound; D007783:Lactones