INFLUENCE OF SOIL TYPE ON GROWTH AND ARTEMISININ CONTENT OF WORMWOOD (ARTEMISIA ANNUA L.) CHEN YOUNG VARIETY IN SOKOTO

Artemisia annua L. produce an array of complex secondary plant metabolite including artemisinin (ART), which kills the principal malarial parasite, Plasmodium falciparum, a compound of current interest in the treatments of drug resistant malaria. However, this compound remain expensive and hardy available on global scale. Synthesis of ART has been proved to be economically impossible. Therefore, increase in yield of natural occurring ART is necessary. The study evaluated the influence of soil types on germination, growth and artemisinin content of A. annua of Chen Young variety in Sokoto agro ecological region of Nigeria and. A greenhouse experiment was conducted in 2017 at Botanical garden of Usmanu Danfodiyo University Sokoto. The seeds were sown in plastic pots containing clay, sandy and loamy soils in completely randomized design with 4 replications. Germination percentage (G), Mean germination time (MT), Coefficient of variation of the germination time (CVt), Mean germination rate (MR), Uncertainty of germination (U) and Synchrony of germination (Z) were evaluated. Growth parameter and Artemisinin content were also determined. ART was determined and quantified with high performance liquid chromatography (HPLC) using calibration curve constructed by plotting the peak area against the concentration (5, 10, 15, 20, 25 µg/ml) of ART standard solutions. The results revealed that soil types had no significant effect on germination and growth parameters evaluated (P<0.05). However, clay had the highest G, MT and CVt than sandy and loamy soils. The highest speed of germination per day was observed on sandy soil. Clay soil had the least values of U (2.277±0.2 bit) while the degree of overlapping germination was frequent in the clay (Z). The result obtained shows that treatment had no significant effect on the growth parameters evaluated (P<0.05). Artemisinin content was significantly affected by soil type with the higher content in sandy soil (37.73 µg/ml) follow by clay and loamy soils with 17.90 and 15.70 µg/ml respectively. This study concludes that A. annua seeds can germinate and survived on different soils type in Savanna region of Nigeria. The study suggested the use of sandy soil in cultivation of the plant for its influence on high artemisinin content.