T.M. Galal - Botany and Microbiology Department, Faculty of Science, Helwan University, Cairo, Egypt.

The present study investigated the impact of environmental pollution, represented in soil,irrigation water and air heavy metals, on the growth and production of Egyptian clovercultivated at south Greater Cairo, Egypt. Plants were sampled through five quadrats (0.5×0.5m), distributed equally in four cultivated farms in unpolluted and polluted sites, at theharvesting time. In addition, soil, air and irrigation water were collected from each farm.Significant differences in air, soil and irrigation water between the polluted and unpolluted siteswere recognized. Plant density, shoot and root lengths; as well as biomass and yield wereremarkably lower in the polluted site. In contrast with chlorophyll b; chlorophyll a andcarotenoids contents were lower in clover cultivated in the polluted site. However, chlorophylla/b ratio was significantly higher in plants from the polluted site. It was found that, As, Cr, Ni,Zn, Ag and V were significantly higher in clover shoots than roots, while Pb, Cd, Cu, Fe, Mnand Co concentrations were higher in the roots. The bioaccumulation and translocation factorsof most heavy metals were greater than unity indicating high potential of the study species forphytoremediation in polluted areas. Egyptian clover accumulated toxic concentrations of Fe, Pb,Ni, Zn, Cd, Cr and Co, which have adverse effects directly on livestock and indirectly on humanhealth through its flow in the food chain. In order to use Egyptian clover as a forage crop, itscultivation should be avoided in polluted areas.

Egyptian clover, Pollutants, Heavy metals, bioaccumulation, Translocation