Effects of cadmium, nickel and lead on growth, chlorophyll content and proteins of weeds

The effects of Cd, Ni and Pb on the growth, chlorophyll (Chi) and protein contents, and content of proteases of potted weed plants Cyperus difformis, Chenopodium ambrosioides and Digitaria sanguinolis were determined. The three heavy metals inhibited the shoot growth but were less suppresive to root growth. They also lowered leaf Chi content. The changes in root and shoot protein and proteases contents of weeds were interrelated. The heavy metal additions to soil increased their contents in both roots and shoots, several times more in roots than in shoots.