Autopolyploidization effect on morpholological, anatomical, reproductive variations and andrographolide content in Andrographis paniculata (Burm. f.) Nees.

Abstract

Artificial polyploidy induction plays a major role in improving various characteristics of the plants. Polyploidization has found widespread application in the breeding of new varieties of medicinal plants due to its numerous advantages and superior performance when compared to their diploid counterparts. This study was undertaken to evaluate the impact of artificial polyploidy on various characteristics of the medicinal plant Andrographis paniculata (Burm. f.) Nees. Aqueous colchicine was applied to Kalmegh seedlings at three different concentrations: 0.05%, 0.1%, and 0.2% (w/v), with varying exposure durations of 6, 12, and 24 h. The duplication of DNA content in induced polyploid plants was confirmed by employing flow cytometry analysis. The most successful induction of polyploidy was accomplished by administering 0.1% (w/v) colchicine for duration of 12 h. The polyploid plants achieved were shorter but with thicker stems, larger leaves, increased leaf area and thickness, larger seeds and flower characteristics than their diploid intact plants. The length and width of stomata were increased in induced polyploid plants, whereas stomata density and index was decreased, in contrast with initial diploid plants. This work follows a facile immersion method and also includes the stomatal and seed detailing of polyploid A. paniculata using SEM. High Performance Liquid Chromatography (HPLC) analysis showed notable (200 fold) increases in andrographolide content of polyploid plants (1.6mg/100g) in contrast with those of diploid plants (0.008mg/100g). Polyploidization also holds significant potential as a breeding technique for future breeding programs involving A. paniculata.