Abstract: The use of preparations based on medicinal plants for the nutrition and protection of plants is gaining more and more importance every year. One of these is horsetail (Equisetum arvense L.), which, due to its silicic acid, suppresses powdery mildew, spotting, gray mold, rust, monilia, etc. in a large percentage. The paper shows the influence of horsetail tea on the germination of the seeds of marshmallow (Althaea officinalis L.), pot marigold (Calendula officinalis L.) and parsley (Petroselinum sativum Hoffm.). The research was conducted in the laboratory for seed production of the Institute for Medicinal Plants Research „Dr Josif Pančić“ in Pančevo, during 2020. Laboratory testing of seeds included examination of morphological and physiological properties (Germination energy - EK, Total germination - UK). Before the seeds were placed for germination, in Petri dishes on filter paper at a temperature regime of 20°C - constant, the seeds were treated with horsetail tea (one part is mixed with 5 parts of water), the other variant represented the control variant where distilled water. Laboratory tests of seeds were carried out in accordance with the Rulebook on the quality of seeds of agricultural plants, during which the following results were recorded: the application of horsetail tea to marshmallow seeds affected an average of 59% of the germinated seeds, while the germination rate of the control variant was much lower and amounted to 26%. Pot marigold seed germination also had a significant increase in horsetail tea treatment. The pot marigold seeds treated with horsetail tea had an average germination rate of 73%, while in the control variety the germination rate was 52%. In the case of parsley seeds, the value of seeds which treated with horsetail tea was 84%, it was not statistically significant compared The influence of horsetail tea (Equisetum arvense L.) on the seed germination of marshmallow (Althaea officinalis L.), pot marigold (Calendula officinalis L.) and parsley (Petroselinum sativum Hoffm.) application/pdf 77887 bytes 2023 horsetail tea (Equisetum arvense), seed germination, marshmallow (Althaea officinalis), pot marigold (Calendula officinalis), parsley (Petroselinum sativum). All rights reserved info:eu-repo/semantics/conferenceProceedings Filipović, Vladimir Dimitrijević, Snežana Popović, Vera Ugrenović, Vladan Šarčević- Todosijević, Ljubica Mrđan, Snežana Prijić, Željana X SYMPOSIUM OF THE SERBIAN ASSOCIATION OF PLANT BREEDERS AND SEED PRODUCERS and VII SYMPOSIUM OF THE SERBIAN GENETIC SOCIETY SECTION OF THE BREEDING OF ORGANISMS eng https://unilib.phaidrabg.rs/o:3115