Responses of Colchicum speciosum L. populations to conventional and nano-fertilizers of nitrogen through changes in morphological and biochemical attributes

There is an increasing interest in the use of nano-fertilizer as an alternative to traditional fertilizers, in order to increase the secondary metabolites in medicinal plants. The present study was conducted to observe the changes in morphological and biochemical properties of three populations of Colchicum speciosum L., from Iran (Filband, Sangdarka, and Kelerd), upon conventional (1.1 and 2.2 mg L-1) and nano-N (1.5 and 3 mg L-1) fertilizers based on completely randomized design (CRD). The anthocyanin and phenolic contents of leaves and corms were determined with a spectrophotometer and corm colchicine was extracted by high-performance liquid chromatography (HPLC). The results represented different responses of morphological and biochemical attributes to populations due to their different origins. Filband with higher altitude showed increased leaf area, plant length, corn weight and diameter when treated with N fertilizers. Increased total phenolic component (TPC) in leaves and corm and also leaf total flavonoids component (TFC) were reported in Filband upon N fertilizers. All fertilizers led to decreased leaf anthocyanin when N fertilizers were applied. A noticeable increase in colchicine was obtained in Kelerd and Sangdarka when plants were treated with 1.5 mg L-1   nano-N fertilizer. Heat map analysis of corm anthocyanin, leaf anthocyanin, leaf TPC, leaf TPC, and colchicine amount showed higher variability under the treatments. According to principal component analysis (PCA), corm TPC, leaf TFC, corm TFC, leaf area, and corm weight were specific traits of Kelerd. In conclusion, different responses of morphological and biochemical traits were reported between populations, and N fertilizers exerted diverse effects on these traits. The population from higher altitudes showed higher phenolic content and lower anthocyanin accumulation under conventional and nano-N fertilizers.