Comparative Analysis of Secondary Metabolites and Metabolic Profiling between Diploid and Tetraploid Morus alba L.

We profiled and quantified primary (amine, organic acids, tricarboxylic acid cycle intermediates, amino acids, and carbohydrates) and secondary metabolites (triterpenoids, phenolic acids, carotenoids, flavonoids, and anthocyanins) in the edible parts (leaves and fruits) of the diploid and tetraploid cultivar Morus alba L. 'Cheongil.' Through comprehensive metabolic profiling, the tetraploid mulberry cultivar was able to produce diverse metabolites supported by higher accumulation patterns of primary and secondary metabolites in their edible parts. In particular, the edible parts of the tetraploid showed higher accumulation patterns of most metabolites (amino acids, carbohydrates, carotenoids, and anthocyanins) than the diploid, which was supported by the results of principal component analyses (PCAs) showing a clear separation between the diploid and tetraploid groups. Additionally, this metabolome study comprehensively described the correlation between primary and secondary metabolites in the edible parts of diploid and tetraploid mulberry cultivars and provided information useful for plant breeding strategies to improve metabolite biosynthesis using polyploidy.