Aluminum toxicity in plants grown in solution culture

Abstract

Abstract Earlirose rice (Oryza sativa L. ) and Hawkeye soybeans (Glycine max L.) were grown in solution culture with A12(SO4)3 in concentrations of 0, 10‐6, 10‐5, 10‐4, 10‐3 M. Only at 10‐4 (slightly) and at 10‐3 M were there yield depressions due to Al. The threshold concentration of Al for toxicity was about 20 μg/g in rice shoots and about 30 μg/g in soybean leaves. The solution level necessary for these concentrations was 8 μg Al/ml. Plant concentrations which caused severe toxicity were 70 μg Al/g plant with 81 μg Al/ml solution. Most Al remained in roots, but leaves contained more than did stems of soybeans. The high Al decreased Fe, Cu, and Mn concentrations in shoots of rice and decreased Fe, Cu, and Zn in roots of rice. The high Al resulted in decreased Fe and Zn in leaves of soybeans. No Fe deficiency symptoms were present due to the high Al.