Selection of Indigo Plant Varieties and Other Plants that Yield Indigo Dye

This study was to investigate the four indigo plant varieties and other plants that give indigo dye. The findings revealed that Nakhon Panom variety gave the greatest yield. The leaf produce was 5520 kg/Acre A followed by Kalasin variety, Mukdahan variety and Sakon Nakhon variety with leaf yield of 4560, 4320 and 3920 kg/Acre, respectively. Kalasin variety was proved to be the best. This variety gave the highest amount of indigo dye, 0.022 g per 100 g of indigo leaves. Mukdahan variety, Sakon Nakhon and Nakon Phanom variety gave 0.017, 0.015 and 0.015 g.of indigo dye respectively. The difference was not statistically different. From the study the plant that could be used to supplement the indigo plants was Marsdenia tinctoria R. Br. which gave 0.025 g per 100 g of indigo leaves at 40 oC, whereas Memecylin edule Roxb. had high acidity, it did not give the color of indigo dye.