DRY-MATTER PRODUCTION OF COMMON BEAN WITH DIFFERENT MAGNESIUM LEVELS IN NUTRIENT SOLUTION

The effect of Mg levels in nutrient solution upon root, stem, leaf, fr uit and total dry matter production of common bean (Phaseolus vulgaris L. cv. Carioca) was studied. Bean plants were grown in Hoagland & Arn on n. 2 solution modified to obtain 2.4, 24.3, 48.6, 72.9 and 97.2 ppm of Mg. The experimental design was a sp lit-plot factorial replicated three times with five Mg levels and five samplings which were done fo rtnightly. Results were compared with those observed in plants submitt ed to a nutrient solution with 48.6 ppm of Mg concentration, considere d the ideal Mg content. Only a mild prejudicial effect was observed wi th Mg excessive levels. Stem, leaves and total dry matter were higher when 2.4 ppm were used, suggesting this level as the concentration cho sen for the culture of common bean.