This experiment was conducted in a greenhouse, in nutrient solution, at the Experimental Center of Campinas, Instituto Agronômico, State of São Paulo, Brazil, in order to define variables and parameters to evaluate and differentiate corn cultivars as to zinc requirement. Twenty four corn cultivars were grown in complete nutrient solution with two zinc levels (0.125 and 0.350 mg Zn/ L), during 30 days, in a randomized complete block design, arranged in a split-plot, with two replications and four plants/ cultivar/ plot. Plant height, top dry matter yield, top Zn concentration and content were the traits scored. Low Zn treatment gave rise to reduced dry matter yields and plant heights, as well as to low top Zn concentrations and contents. The cultivars D-468, ICI-791152 and C-701 were the best in the low zinc level. By the other hand, the cultivars C-808, Hatã-2000, OC-5045-6 and BR-201 were more responsive to the high Zn level. High and positive correlation (r = 0,86) was estimated between plant height and top zinc content, which might be useful in future selection schemes. However, more research is needed to quantify, with higher precision, genotype differences in zinc demands.
corn; cultivars; plant selection; zinc deficiency; nutrient solution