The effects of NPK fertilizers on growth, ornamental traits and corm yield of wild species of colchicum (Colchicum kotschyi Bioss)

This research was carried out with the aim of investigating the effect of different levels of chemical fertilizers on vegetative and ornamental characteristics of wild species of colchicum (Colchicum kotschyi Boiss). For this purpose, a pot factorial experiment was conducted based on completely randomized design with three replications including three levels of nitrogen (N= 0, 60, 120 kg ha-1) three levels of phosphorus (P= 0, 30 and 60 kg ha-1) and three levels of potassium (K= 0, 40 and 80 kg ha-1) at Ferdowsi University of Mashhad during 2015-2016. Studied traits was included leaf number and area, leaf fresh and dry weight, chlorophyll a, b and carotenoids, number of flowers and flower diameter, and length, diameter and fresh and dry weights of the corms. Results of interaction effects of nitrogen, phosphorus and potassium levels showed that the highest number of flowers, leaf number, fresh and dry weights and corrn diameter was obtained in 60:60:40 kg ha-1 of N×P×K, respectively. The highest flower diameter, chlorophylls and carotenoids were obtained in treatments of 60:60:80 kg ha-1 from N×P×K, respectively. Overall, results indicated that the application of moderate levels of N, K and P improved most vegetative and ornamental traits in C. kotschyi Boiss. More research on ornamental aspects and efforts to preserve, domestication and propagation of native species of colchicum, can lead to the sustainable use of this ornamental plant in landspace.