Genetic Diversity Study of Andrographis paniculata (Burm. F.) Wall ex. Nees from the Southern Districts of Kerala Using SSR Markers

Abstract

The study aims at finding the genetic diversity of 35 Kiriyathu (Andrographis paniculata (Burm. F.) Wall ex. Nees) ecotypes from the Southern districts of Kerala using SSR markers. Kiriyathu ecotypes were collected from nine different Agro Ecological Units (AEUs) of south Kerala and raised in College of Agriculture, Vellayani (AEU 8) from January to June, 2024.  Diversity assessment was done using ten SSR primers, among which seven were found to be polymorphic viz., Ando 4-26, Ando 4-27-2, Ando 4-43/1, Ando 5-12-1, Ando 5-14-2, Ando 5-26-2 and Ando 5-29. The (Polymorphism Information Content) PIC value ranged from 0.16 to 0.64.  The dendrogram representation could gather the ecotypes into three separate clusters viz., Cluster I, Cluster II and Cluster III.  Cluster I was further divided into seven subclusters containing 27 ecotypes while cluster II and cluster III contained five and three ecotypes respectively. Furthermore, the scatter plot developed through Principal Coordinate Analysis (PCoA) could identify genetically distinct ecotypes viz., Karunagappally, Sasthamcotta, Vellimon and Chirakkara. In an overview, the genetic heterogeneity among the Kiriyathu ecotypes is possibly attributed to genetic mixing via germplasm transfer during its wide history of conventional usage. Moreover, the limited gene flow can be due to self-pollination, low pollen and seed dispersal rates.