Photosynthesis and Antioxidative Systems of Andrographis paniculata as Affected by Compost Tea Rates

Andrographis paniculata (Burm.f.) Nees is a medicinal herb in the family Acanthaceae. The leaves of the mature plant contain abundant diterpinoids of medicinal properties.The objectives of the present study were to investigate the impacts of compost tea rates on photosynthesis parameters and antioxidant reactions of A. paniculata. The plant was propagated using seed and planting in a polybag. After four weeks, the plant was transplanted into polybag sized ۲۰ cm×۲۵ cm. Compost tea was used at rates of (۰, ۲۵, ۵۰, ۷۵ and ۱۰۰%). Treatments were arranged in randomized completely block design (RCBD) with three replicates. Before flowering stage, the plants were harvested. The results revealed that rates of compost tea significantly affected total dry weight, leaf area, chlorophyll, stomatal conductance, FRAP and total flavonoid contents (P≤۰.۰۱), while there were no significant difference on DPPH reduction, and total phenolic contents and photosynthetic rate. Soil amendment with compost tea gave a favorable effect on growth and improved soil pH and CEC. Total flavonoid was highly significantly differences among the treatments. The greatest TDW (۲۶.۱۵ g), FRAP (۹۶.۰۳% of inhibition) and flavonoid (۱۹۴۳.۷ mg/g) were observed at the ۷۰% rate of compost tea. The highest rates of compost tea (۱۰۰%) significantly decreased the phenolic and flavonoid compounds. These results suggested that A. paniculata could reach high biomass and quality characteristics with ۵۰ and ۷۰% rate of compost tea. However, in general compost tea had a good potential to improve soil pH and increase plant growth and antioxidant contents.

Keywords:

Andrographis paniculata , Antioxidant , Compost tea , Photosynthesis