Characteristization of Morphological traits to study genetic diversity of java tea (Orthosiphon stamineus Benth.)

Orthosiphon stamineus Benth. or commonly known as java tea or misai kucing, is a medicinal herb belonging to Lamiaceae family. Many believe that there are two different varieties of java tea based on the color of flower; white and purple varieties. Since this plant is originated from Southeast Asia, there must be diversity between and within these two varieties. The objective of this research was to study the morphological characters among 30 accessions from both varieties collected from various places in Malaysia and Indonesia. This morphological study showed that both varieties had simple, petiolated dark green leaves which are arranged in opposite pairs and exhibit serrate margin. The white variety which produced rhomboid leaf shape had light green colour for leaf venation while the purple variety that produced ovate leaf shape possessed light purple colour for the venation. Both varieties produced square shaped stem. The flower colour was a distinguishable factor in which the white variety had white coloured corolla and purple colour for the corolla for purple variety. The statistical analysis showed the significant differences in all observed quantitative morphological attributes. There were four clusters based on the morphological characteristics observed from both white and purple plants as depicted by the dendrogram.