Nonlinear regression modelling of rye and foxtail germination behavior under allelopathic effects of peppermint, chicory and sage

Germination is one of the essential period of plants growth that can be affected by chemical agents released by means of other plants. Nowadays, utilization of allelopathic natural compounds is a good alternative to synthetic compounds. Therefore, a factorial experiment was conducted that based on completely randomized design (CRD) with 3 replications. Treatments were included two weeds (wild rye (Secale cereale) and foxtail (Alopecurus myouroides)), three medicinal plants (peppermint (Mentha piperita), chicory (Cichorium intybus) and sage (Salvia officinalis)) and 5 level of aqueous extract (0, 5, 25, 50 and 100 percent). Peppermint and sage extracts have more effects than chicory on wild rye germination percentage and seedling growth. While, peppermint extract was the most effective in germination percentage of foxtail. The minimum plumule length of both weed species was obtained from 50 and 100% concentration of chicory and sage extract. The best fitted models of germination percentage of foxtail in different extracts concentration of peppermint, chicory and sage were Rational Model, MMF and Ratkowsky Model, respectively. Also, for wild rye were Farazdaghi-Harris, Modified Power and Logistic, respectively.