THE EFFECT OF ALUMINUM ON ENZYME-ACTIVITIES IN WHEAT ROOTS

The effect of aluminum (Al) on the extractable activity of enzymes of carbon metabolism from wheat (Triticum aestivum L. cv. Vulcan) roots has been studied. The addition of 75 muM Al to nutrient solutions supporting growth of 4-day-old seedlings inhibited root extension after 24 h and 48 h by 64 % and 73 %, respectively, compared with untreated seedlings. The most notable change observed with this concentration of Al was an increase in the amount of alcohol dehydrogenase activity in the wheat roots. The specific activity of alcohol dehydrogenase increased by approximately 50 % after 24 h, and more than doubled after 48 h. The specific activities of sucrose synthase and lactate dehydrogenase were also increased in extracts from roots of Al-treated seedlings. The results indicate that an early effect of Al on wheat roots may be a shift from aerobic to anaerobic metabolism.