CADMIUM PHYTOTOXICITY ON AFRICAN YAMBEAN (SPHENOSTYLIS STERNOCARPA) (VAR. TSS 90)

ABSTRACT

African yam bean (Sphenostylis sternocarpa) is known for both its seed and tubers but when contaminated it could cause harm to both the plant and even consumers. Cadmium (Cd) which is a heavy metal was used to pollute the plant to check the effect of it toxicity on the plant. The experiment was conducted in marked plot measuring 10 m x 20 m and soil was gotten from 10 random spot in the Botanical Garden of the University of Benin, Benin City. The seeds were obtained from IITA and was planted in bags and name TSs 90 variation. 12mg/kg of cadmium was used to pollute the soil. The growth of the plant was determined on daily and weekly basis. At the end of the experiment, it was observed that the growth of the polluted plant was affected by Cadmium compared to that of the unpolluted plant. In the plant affected by cadmium, there was significant reduction in root nodules and yield. Also, chlorophyll a and b was decreased in leaves. When plants grow in soils treated in heavy metals especially cadmium, it would lead to death of the plant