Evidence of molecular marker for genetic relationship of Asystasia gangetia (Linn) T. Anderson

Abstract

Asystasia gangetica
(L.) T. Anderson (Acanthaceae) is widespread throughout the old world tropics. The plant is cultivated as an ornamental and various parts of the plant are also used traditionally for many ailments and diseases. Two subspecies are recognized in Thailand (1) A. gangetica micrantha that flowers are mostly white with two parallel purple blotches lines on the bottom petal lobe and (2) A. gangetica gangetica that flowers are various shades color as a pink, mauve or purplish with paler throats and white or cream with pale yellowish throats. However, there are comparatively a lesser number of reports focusing on intraspecific genetic diversity studies. The genetic diversity of a local subpopulation of A. gangetica was surveyed using random amplified polymorphic DNA (RAPD) analysis. A total of sixty-four random primers were used and eight primers (OPA-01, OPA-12, OPA-16, OPA-18, OPA-20, OPC02, OPC-05 and OPH-05) were produced reproducible fragments with easily recordable bands which were selected for analysis. A total of 91 bands were detected with an average of 11.4 bands per primer. The genetic similarities were estimated from banding pattern using UPGMA clustering method. The Pearson’s similarity coefficients were used to construct a UPGMA dendrogram. Pair-wise estimates of genetic similarity ranged from 0.17 to 1.00. Five primary genotypes were found within a sampling of 30 individuals: white flowers with purple markings on the bottom petal lobe (A. gangetica micrantha), purple, white, pink and yellow flowers. Our result showed the RAPD marker for assessing genetic relationship among A. gangetica that correspond to flower color.