Allelopathic Potential of Some Essential Oil Bearing Plant Extracts on Common Lambsquarters (Chenopodium album L.)

Allelopathy can be regarded as a component of biological control in which plants are used to reduce development of other plants. Allelopathy refers to the direct or indirect chemical effects of one plant on the germination, growth or development of neighboring plants. The allelopathic effects of extracts of mint (Mentha piperita L.), thyme (Thymus vulgaris L.), rosemary (Rosmarinus officinalis L.), coriander (Coriandrum sativum L.) and sage (Salvia officinalis L.) on seed germination and some growth characteristics of common lambsquarters (Chenopodium album L.) were investigated. Aqueous extracts of aromatic plants at 0,1, 2.5, 5, 10 and 20 % concentrations were applied to determine their inhibition effects on seed germination; seedling shoot and root length of C. album seed under laboratory conditions. The extracts of tested plant species caused inhibitory effects on seed germination and seedling length of C. album. Allolapaticity increased progressively with the increasing extract concentration. The results showed that total germination inhibition of C. album depended on the extract concentration; ranged from %13 to 100. The maximum inhibition (100%) rate for germination was obtained from the highest extract concentration for all test species. Extracts of mint, thyme, rosemary, coriander and sage could be used as alternatives herbicides.