Corn (Zea mays L.) as a bioindicator of soil impacted by Al2 (SO4 )3

Abstract

Corn (Zea mays L.) is a widespread graminea in Brazil and among all cultivars, is the one of greater economic interest in the country. Aluminum (Al+3) is one of the metals which reduces plant growth, as well as is responsible for physiological and metabolic alterations. This study was carried out with seedlings about 5 cm long, exposed to water (control), and solutions 15 mg.L-1 and 25 mg.L-1 of Al2 (SO4)3. The irrigation occurred daily, and was sufficient to keep soil moisture, without apparent loss of liquid in the bottom of the pot, and were interrupted at the 35th day. During the next 20 days, the plants were wetted with tap water. During the experimental period, corresponding to: 96 hours 15, 25, 35, 45 and 55 days, leaf samples of the second pair of plagiotrophycal were used for the extraction of Acid Phosphatase (ACP), and at the same time, animals were biometrics stem and determine the dry weight of the roots. Acid phosphatase was inhibited in both treatments, with significant response after day 25O (p ≤ 0.05). The enzymatic activity was partially recovered after discontinuation of treatment compared to the control. Stem length was not significantly different between treatments throughout the experimental phase. The weight of the roots exposed to aluminum was significantly lower when compared to the control. Probably, this reduction was due to lower growth fasciculate roots, which leads to a deficiency in the process of absorption of nutrients. These results suggest that a soil affected with aluminum salts may interfere with the metabolism in the absorptive process plant and, consequently, the production plant.