Effect of pH on growth and indigo coloring quality of Hom (Baphicacanthus cusia (Nees.) Bremek.) at Phrae Province

Abstract

The study on effect of pH value on the indigo color quality of Hom (Baphicacanthus cusia (Nees.) Bremek) was done in Phrae province. The objective was to determine the initial pH of the soil to the growth and color quality of the Hom. We have measured the initial and final growth of plants in different pH of potting soils and the color quality. The results showed that suitability adjusted pH at 4.5 with average soil moisture content (96.25 %) and exposure in the greenhouse was 70% (101.87) had high supported on maximum growth. The increased growth was detected in most plant parts, stem height (10.66 cm), root length (5.16 cm), number of branches (1.66 branches), and number of leaf (15 leaves). While, the treatment without pH adjustment provided the standard color quality of Hom which express by values of L* (21.38), a* (-3.18), and b* (-5.93). Value of L* indicating the color lightness with yield to dark color when closed to 0, while, -a* and -b* expressed the green and blue color, respectively. The amount of leuco-indigo was 88.53 ?ml, High leuco-indico indicating the efficiency of the color absorption in the fabric. However, pH adjustment to 4.5 also provided a standard color quality, even though, less than without pH adjustment which varied values were found, L* (28.34), a* (-4.83), b* (-3.09), and leuco-indigo (77.20 ?ml). Indicating Hom can be used to solve the acid soil problem. Then, the communities will get the benefit from cultivating which contributes to economic development and development into community enterprise groups in the future.

Keywords: pH; Indigo; Baphicacanthus cusia (Nees.) Bremek; Leuco-indigo

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