Reações da soja a chuva ácida e solo contaminado

Abstract

Plants of Glycine max (L.) Merrill cv. Uberaba grown in sand, (LVA) soil of Cubatão and in soil of Cubatão with corrected acidity were exposed, from the V2 stage, during one week, to simulated acid rain with composition similar to that of Cubatão, to study the effects of the treatments on: amount of epicuticular wax, diffusive resistance to C02 and activities of peroxidase and nitrate reductase enzymes. Acid rain caused remova! of epicuticular wax but it did not affect adaxial and abaxial diffusive resistances. Acid rain promoted an increase of peroxidase activity and a decrease of nitrate reductase activity, occurring an inverse effect for nitrate reductase in roots. The correction of the acidity of Cubatão soil eliminated its detrimental effects. At the end of the experimental period, evident lesions similar to those caused by fluor accumulation were observed in the aerial part of the plants.