Allelopathic effects of volatile cineoles on two weedy plant species

• Published in: Journal of chemical ecology Vol. 26; no. 1; pp. 303 - 313
• Main Authors: ROMAGNI, J. G, ALLEN, S. N, DAYAN, F. E
• Format: Journal Article
• Language: English
• Published: New York, NY Springer 2000; Springer Nature B.V
• Subjects: 1,4-cineole; 1,8-cineole; Animal and plant ecology; Animal, plant and microbial ecology; Autoecology; Biological and medical sciences; Chlorophyll; Essential oils; Flowers & plants; Fundamental and applied biological sciences. Psychology; Photosynthesis; Plant growth; Plant species; Plants and fungi; Echinochloa crus-galli; Monocotyledones; Weed; Quantum yield; Allelochemicals; Photochemical conversion; Phytotoxicity; Leguminosae; Gramineae; Cassia obtusifolia; Dicotyledones; Angiospermae; Monoterpene; Spermatophyta; Essential oil; Photosynthesis; Interspecific relation
• DOI: 10.1023/a:1005414216848
• ISSN: 0098-0331

The volatile monoterpene analogs, 1,4-cineole and 1,8-cineole, have been identified as components of many plant essential oils, but relatively little is known about their biological activities. We compared the effects of 1,4- and 1,8-cineole on two weedy plant species by monitoring germination, mitosis, root and shoot growth, chlorophyll content, and photosynthetic efficiency. 1,4-Cineole severely inhibited growth of roots and shoots, causing cork-screw shaped morphological distortion, whereas 1,8-cineole caused a decrease in root growth and germination rates. Chlorophyll fluorescence data (yield and F^sub v^ / F^sub m^) indicated that 1,4-cineole caused significantly higher stress (P ≤ 0.001) to photosynthesis when compared to controls. Mitotic index data showed that 1,8-cineole severely decreased (P ≤ 0.001) all stages of mitosis when compared with controls, while 1,4-cineole only caused a decrease in the prophase stage (P ≤ 0.05). Although superficially similar in structure, these two cineoles appear to have different modes of action.[PUBLICATION ABSTRACT]