Effects of different basil hydrosol doses on the germination and shoot and root lenghts of basil (Ocimum basilicum) and quinoa (Chenopodium quinoa) seeds

Abstract

Objective: Medicinal and aromatic plants (MAPs) have allelopathic effects on seed germination, root and shoot length due to the chemicals included in their extracts or essential oils. In this study, the changes in the germination rate, and shoot and root length of basil (Ocimum basilicum) and quinoa (Chenopodium quinoa) seeds exposed to different concentrations of basil hydrosol have been investigated. Material and Methods: The treatments included distilled water (control), tap water and different concentrations of basil hydrosol (0.5, 1, 1.5 and 2 ml). The study was conducted with a randomized complete block design with 3 replications. Twenty seeds of each species were placed on a filter paper in Petri dishes. For each treatment, 2 ml test solution (distilled water or tap water or hydrosols) was applied to each replicate. All the experiments were carried out at 29±1°C, dark photoperiod using a drying oven under laboratory conditions. Results: All the basil and quinoa seeds were successfully germinated within 3 to 7 days. Following the treatments, the root and shoot lengths changed from 0.10 to 1.24 cm and 0.53 to 2.15 cm, respectively for the basil and from 0.32 to 3.59 cm and 0.63 to 1.97 cm for the quinoa. Conclusion: Increasing the applied dosage of basil hydrosol significantly decreased the seed germination rate and shoot and root length. In particular, 2 ml hydrosol prevented seed germination by more than 50% in basil.