Abstract

DISTINCTION IN MORPHOLOGICAL AND BIOCHEMICAL CHANGES IN VALUABLE MEDICINAL HERB JUSTICIA ADHATODA UNDER ELEVATED CO2

S. Saravanan* and S. Karthi

ABSTRACT

Increasing atmospheric CO2 concentration is generally expected to enhance plant growth, allocation and chemical composition of alkaloids in medicinal plants. Justicia adhatoda an important medicinal plant which is being cultivated commercially in India for different purposes. The response to the elevated CO2 concentrations of various medicinal plants was studied with reference to growth and biochemical changes. It has gained a great interest from the pharmaceutical industry; the alkaloids vasicine from its sap has been shown to be an effective treatment for suppressant, cough and bronchodilator. It has a great importance in studying different parameters of J. adhatoda. The present study was carried out for growth and bio-chemical changes of J. adhatoda in different elevated CO2 levels. Open top chambers (OTCs, diameter: 3.0 m, height: 3.0 m) were used to expose plants to ambient and elevated CO2 concentration (600ppm and 900 ppm). The experiment was conducted for a period of five months. Carbon- di- oxide enrichment studies in special open top chambers help us in understanding the changes at individual plant growth and Biochemical changes. The plant growth revealed that the maximum fresh weight (25.29 gm), shoot length (33.73 cm) were observed in 600 ppm+RH and the maximum number of leaves (29 Nos.) were observed in 900 ppm. The maximum number of roots (18.50 Nos.) and the longest root lengths (20.1 cm) were observed in 600 ppm+RH. In the ambient condition, the above said characters were found to be in the lowest level. The bio-chemical analysis revealed that the highest alkaloid (671.61 mg/ml) and flavonoid (242.45 mg/ml) were recorded in control. Tannin (140.06mg/ml) and saponin (64.50gm) were recorded in higher level at 900 ppm. In ambient condition, the highest phenol (207.66mg/ml) was recorded.

Keywords: Justicia adhatoda, Elevated CO2, Growth parameters, Bio chemical changes.