Morphological and chemical studies of artificial Andrographis paniculata polyploids

Andrographis paniculata (Burm. f.) Nees (AP) is commonly used for the treatment of many infectious diseases and has been cultivated widely in Asian countries, and has been included in United States Pharmacopoeia as a dietary supplement, but the cultivars of A. paniculata are not abundant due to its self-pollinated. With the aims to enrich AP resources and provide materials for after breeding we explored the polyploidy induction. Different explants, colchicine concentration, and treatment time were tested. After identification by flow cytometry, eleven polyploid plants with different morphologic traits were obtained. The agronomic traits and andrographolide concentration of the polyploids were improved greatly. One of the polyploids (serial 3-7) was chosen for further study. The traits of the second and third generation polyploids (serial 3-7) were stable. Compared with the normal plants, the seeds (2nd generation) weight increased by 31%, and the andrographolide concentration of the leaves increased by 14% (2nd) and 28% (3rd). In conclusion, AP autopolyploids with different morphologic traits were established successfully for the first time, and the polyploids induction might be effective for crop improvement of AP.