Determination of herbicidal effects of essential oils obtained from species of Hypericum

In this study, bio-hebisidal effects of herbal orginated essential oils on seed germination, root and stem developments. For this purpose; leaf, flower and stem belong to Hypericum lydium Boiss., Hypericum microcalycinum (Boiss. Et Helder.) Robson, Hypericum perforatum L. ve Hypericum scabrum L. were collected from Erzurum region and essential oils of these materials were used. The essential oils isolated from H. perforatum, H. scabrum, H. microcalycinum ve H. lydium were analyzed by GS-MS method. Main essential oil component were found to be in order to Caryophyllene oxide (%38,51), β-Caryophyllene (%48,37), β-Caryophyllene (%27,86) ve α-Pinene (%18,88). Derived essential oils were applied to weed seeds of Chenepodium album L., Amaranthus retroflexus L., Cichorium intybus L. and Convolvulus arvensis L. Increasing the application dose derived from areal parts of H. perforatum, H. scabrum, H. microcalycinum ve H. lydium decreased the length of roots and stems and seeds germination. It was determined that essantial oil inhibited the germination of weed seeds of the rote of %68,08 - %100. In greenhouse experiments deaths of plants were found to be rate of %14,42 - %80 at the end of 48 hours. As a result, it was determined that the essential oil from Hypericum species could be applied as alternative bio-herbicide to C. album, A. retroflexus, C. intybus ve C. arvensis seeds caused serious problems on culture areas of our country