Chemical composition and growth characteristics of Amorphophallus bulbifer

Konjac is an important horticultural vegetable and characteristic cash crop. Amorphophallus bulbifer has many advantages such as high yield, good quality and strong resistance. However, the awareness of collection and classification of germplasm resources is not strong, the germplasm resources are mixed in planting, there is a lack of good varieties, and the chemical composition of A. bulbifer is still unclear. Therefore, 5 self-selected A. bulbifer germplasm resources were used as experimental materials to study the growth, physicochemical properties and nutritional components by correlation analysis, principal components analysis (PCA) and metabolomic analysis. The results showed that A. bulbifer had strong growth adaptability, konjac glucomanan (KGM) content was 34.88% to 65.72%, viscosity was up to 19513.33 mPa.s, in addition, it was rich in starch, crude protein, amino acids and other nutrients. The aboveground growth and underground yield of konjac had significant positive correlation with each other (p< 0.05) and KGM had significant positive correlation with viscosity (r = 0.8, p< 0.001), but had significant negative correlation with starch, soluble sugar and crude fiber (p< 0.01), respectively. 945 metabolites were detected in the metabolome. Besides the primary metabolites, there were also abundant secondary metabolites such as flavonoids, alkaloids, organoheterocyclic compounds, phytohormones and other secondary metabolites. Carbohydrates and its derivatives, amino acids and its derivatives, organic acids and its derivatives, organoheterocyclic compounds and lipids were the main differential metabolites, among which D-Gluconic acid was an important differential metabolite. In conclusion, this study confirmed that A. bulbifer has good physical and chemical properties and rich nutritional components, suitable for the development and utilization of high value-added products.