Al-Moula, A.A.F. and Al-Hashemi, F.H. 2025. Effect of Tryptophan and Nano NPK Fertilizer on The Flowring Growth of Two Cultivars of Narcissus Spp. Journal of Scientific Research in Medical and Biological Sciences. 6, 1 (Jan. 2025), 38-48. DOI:https://doi.org/10.47631/jsrmbs.v6i1.896.