title: 1,8-Cineole inhibits root growth and DNA synthesis in the root apical meristem ofBrassica campestris L.
abstract: 1,8-cineole is a volatile growth inhibitor produced bySalvia species. We examined the effect of this allelopathic compound on the growth of other plants usingBrassica campestris as the test plant. Cineole inhibited germination and growth ofB. campestris in a dosedependent manner. WhenB. campestris was grown for 5 days with various concentrations of cineole, the length of the roots was found to be shorter as the concentration of cineole increased, whereas the length of the hypocotyl remained constant up to 400 μM cineole, indicating that cineole specifically inhibited growth of the root. The mitotic index in the root apical meristem of 3-day-old seedlings decreased from 5.6% to 1.6% when exposed to 400 μM cineole, showing that cineole inhibits the proliferation of root cells. We then examined the effect of cineole on DNA synthesis by indirect immunofluorescence microscopy using antibody raised against 5-bromo-2'-deoxyuridine (BrdU, an analogue of thymidine) in thin sections of samples embedded in Technovit 7100 resin. The results clearly demonstrated that cineole inhibits DNA synthesis in both cell nuclei and organelles in root apical meristem, suggesting that cineole may interfere with the growth of other plant species by inhibiting DNA synthesis in the root apical meristem.
authors: Department of Biological Sciences, Graduate School of Science, University of Tokyo, Hongo, 113, Tokyo, Japan.|Tochigi Research Laboratories, Kao Corporation, 2606 Akabane, Ichikaimachi, 321-34, Haga, Tochigi, Japan.
authors: R
authors: R
authors: Koitabashi
authors: Department of Biological Sciences, Graduate School of Science, University of Tokyo, Hongo, 113, Tokyo, Japan.|Department of Cell Biology, Institute for Molecular and Cellular Regulation, Gunma University, 371, Maebashi, Gunma, Japan.
authors: T
authors: T
authors: Suzuki
authors: Department of Biological Sciences, Graduate School of Science, University of Tokyo, Hongo, 113, Tokyo, Japan.
authors: T
authors: T
authors: Kawazu
authors: Department of Biological Sciences, Graduate School of Science, University of Tokyo, Hongo, 113, Tokyo, Japan.
authors: A
authors: A
authors: Sakai
authors: Department of Biology, Kyouritsu Women's Junior College University, 102, Tokyo, Japan.
authors: H
authors: H
authors: Kuroiwa
authors: Department of Biological Sciences, Graduate School of Science, University of Tokyo, Hongo, 113, Tokyo, Japan.
authors: T
authors: T
authors: Kuroiwa
keywords: 1,8-cineole; Allelopathy; Brassica campestris; DNA synthesis; Salvia