PHYSIOLOGICAL STUDIES ON THE EFFECTS Of SOME POLLUTANTS ON SUGAR BEET PLANT

Abstract

Two types of experiments were carried out to investigate the effect of different heavy metals on the growth, photosynthesis, some metabolic products and micro and macronutrients in leaves and roots of sugar beet plants (Beta vulgaris).

The first type contained several controlled experiments which carried out at the Forest Botany Institute, Gottingen University, Gennany during the period of October 1994 to Juli 1995. The plants were grown in a chamber at 25-26 °C, 65-70% relative humidity and ISO -tE m2 ' s'1 light intensity. The plants were inigated with i/5 diluted of Long Ashton solution containing 0, 0.1, 1.0, I 0 and I 00 -tM Cd, Cu or Zn added in the fonn sulphate and mixtures of 1.0 (Cd+Cu), 1.0 (Cd+Zn) or 1.0 (Cu+Zn) as well as mixtures of 0.1, 1.0 and 10 -tM of (Cd+Cu+Zn).

In addition, the effects of some macronut:rients on metal uptake and toxicity were canied out by adding to the nutrient solution containing 0, I.0 -tM Cd, 0, I 0 -tM Cu and 0, I 00 -tM Zn, different concentrations of Ca, K or Mg. The concentrations of K and Ca were 200, 800, 1600 and 3200 t!VI, while the concentrations of Mg were 100, 300, 600 and 1200 LM.

The obtained results are summarized as follows:

(I) Plant growth characters; shoot and root lengths as well as shoot and root fresh and dry weights, were in general decreased by adding the heavy metals of Zn, Cu and Cd in the nutrient solution either separetely or 111 combinations.