Raw and Fermented Alfalfa Brown Juice Induces Changes in the Germination and Development of French Marigold (Tagetes patula L.) Plants

L. 'Csemő') plants which were treated with 0.5-10% fermented and non-fermented BJ, with tap water applied as a control. Applying 0.5% fermented BJ significantly improved seed germination compared with non-fermented BJ, resulting in an increase of 9.6, 11.2, 10.9, and 41.7% in the final germination percent, germination rate index, germination index, and vigor index, respectively. In addition, it increased the root and shoot length by 7.9 and 16.1%, respectively, root and shoot dry mass by 20 and 47.6%, respectively, and the number of leaves by 28.8% compared to the control. Furthermore, an increase in contents of water-soluble phenol, chlorophyll a and b, and carotenoid was reported upon the application of 0.5% fermented BJ, while peroxidase activity decreased. Our results prove that alfalfa BJ can be enrolled as a biostimulant as part of the circular farming approach which supports the sustainable horticultural practice.