Effect of dust contamination on soil, leaf chemical composition and fruit quality of piscium guava L.

ABSTRACT

The aim of the present study is to evaluate the effect of dust contamination at different distances on soil, leaf chemical composition, fruit set and fruit quality of Psidium guajava L. The study revealed that, Ni. Pb and Cd contents in soil decreased with increasing distance from the source of dust and with increasing soil depth. In leaves. P, Na, K, Ca and Mg exhibited an appreciable increase in their contents in trees adjacent to the road. Chlorophyll contents showed a slight increase and the variation in total available carbohydrates was insignificant as compared with trees distant from the road. In the two studied seasons [1990 and 1991], the average fruit set, mature fruits and fruit weight was signifcantly lower in trees adjacent the road. The reverse was true for core/flesh ratio. The contents of citric acid and vitamin C were significantly higher in fruits adjacent and distant from the road respectively. Concerning the heavy metals content in leaves and fruit parts [flesh and core], the results indicated that Mn, Ni, Pb and Cd in leaves and Ni, Pb and Cd in fruit parts significantly higher in trees adjacent the road