Effect of Colchicine on Andrographis Variety Phichit 4-4 for Plant Breeding in Stem and Leaf Characteristics

Background: Andrographis paniculata (Burm.f.) Nees is a plant native to Thailand. Thais use andrographis as an herb for treating the common cold. During pandemic the Andrographis leaves and stem has been used to treat COVID-19. In Thailand, there is a demand for andrographis, leading to a shortage of andrographis. Breeding andrographis by inducing polyploid plants is one way to increase yields in stem and leaf sections. Methods: The study was conducted in May-September 2022 at Kasetsart University, Chalermprakiat Sakon Nakhon Campus, Thailand, by inducing andrographis of Phichit 4-4 variety into polyploids with colchicine concentrations of 0.0, 0.1, 0.2, 0.3 and 0.4%. After that, study of agricultural characteristics and identification of polyploids with flow cytometry analysis were carried out. Result: A study on the characteristics of andrographis Phichit 4-4 after inducing colchicine in various treatments at 2 months of age showed that andrographis received with colchicine had a higher stem height and number of node than those without colchicine. Comparison of characteristics of andrographis Phichit 4-4 at 4 months of age. The number of leaves per plant and leaf weight are greater than those treated without colchicine. When examining the polyploids of andrographis plants using flow cytometry analysis, it was found that the plants with abnormal characteristics with tall stems, large leaves, thick leaves, dark green leaves are mixoploids. Studies have found that there are many abnormal plants in colchicine-treated treatments. 0.1% for 24 and 48 hours.