RESPONSE OF HELLERI HOLLY TO NITROGEN FORM AND ALUMINUM IN SOLUTION CULTURE

Rooted cuttings of 'Helleri' holly (Ilex crenata Thunb. 'Helleri') wer e grown in solution culture for 101 days. On day 31, plants were expos ed to 0 and 54 mg . l(-1) aluminum (Al) and five nitrogen (N)-form tre atments of varying ammonium:nitrate (NH4+:NO3-) ratios (0:100, 25:75, 50:50, 75:25, and 100:0, percent basis) at pH less than or equal to 4. 0. Root growth decreased with increasing NH4+ concentration in solutio n. Uptake of phosphorus (P) was increased by Al. Manganese (Mn) and ir on (Fe) uptake were reduced by Al. No significant N-form effects were determined for nutrient uptake data. Calcium (Ca), magnesium (Mg), pot assium (K), Fe, Mn, copper (Cu), zinc (Zn), and boron (B) tissue conce ntrations decreased in solutions containing 54 mg . L(-1) Al; while ti ssue P concentrations increased. Nitrogen source exerted less influenc e on growth and nutrition of 'Helleri' holly than Al.