Winter rape seeds germination of Cannabis sativa inflorescence aqueous extract

Abstract

The experiment was carried out in the laboratories of the Institute of Biology and Plant Biotechnology of the Faculty of Agronomy, Vytautas Magnus University in 2018–2019. The aim of the study was to determine the allelopathic effect of 2, 1 and 0.5% solutions of Cannabis sativa L. inflorescence aqueous extract on the germination rates of winter rape ‘Cult’ cultivars prepared from the fresh extract and the extract stored for 30 days (1 month) and 45 days (1.5 months). The prepared extract was stored in a refrigerator (4 ± 1°C). The control was distilled water. Solutions from the freshly prepared extract and the extract stored for 30 days were found to inhibit seed germination power and to stimulate it after 45 days. Seed germination was most inhibited by a 2% solution of the freshly prepared inflorescence extract. After 30 days, the solutions prepared from the preserved extract had no significant effect on germination, and after 45 days, the solutions stimulated germination. The germination of the 1% concen­tration solution was by 10.14 relative units significantly higher than that of the control. Assessing the changes in roots and sprouts, it was found that essentially the shortest roots were when germinated in the 2% concentration solution, regardless of the storage time of the extract. In the solutions with 1 and 0.5% concentration, the sprouts lengthened with increasing the shelf-life of the extract. The lowest root/ sprout length ratio was in this solution. In the 1% solution, the sprouts grew consistently and the roots shortened. Changes in roots mass were more dependent on the concentration of the solution: as the concentration decreased, their mass increased. In the 0.5% solution, the weight of sprouts increased consistently with increasing the storage time of the extract. The evaluation of Vigour index based on the green mass of rape sprouts and roots showed that the concentration in 0.5% solutions through the whole experiment was significantly higher than in the control and increased with increasing the shelf-life of the extract.