Maize (Zea mays L) cultivars nutrients concentration in leaves and stalks.

There is pressure for crop residue removal for use as biofuel, animal feed, animal bedding and many other func¬tions which may increase nutrient export. However, there is little information about nutritional composition of maize stover considering the wide variability of cultivars used. The aim of this study was to evaluate the influence of maize cultivar on macronutrient (P, K, Ca, and Mg), micronutrient (Fe, Mn, Zn, and Cu) and Na concentration in leaves and stalks. We selected five pairs of cultivars, ranging from creole to high potential hybrid (creole, commer¬cial variety, single, double and triple cross hybrid). The cultivars were cropped under field conditions in high fertile Rhodic Ferralsol Eutric during two growing seasons. The first was characterized by severe drought (2005/2006) while the second with an abundant water supply (2006/2007). The leaf and stalk concentrations of P, K, Ca, Mg, Fe, Mn, Na, Zn, Cu, and C/P ratio were quantified at maturation stage. The results indicated that the P concen¬tration in leaves and stalks was inversely related to the technological level when simple hybrid was compared to creole cultivars. Similar behavior was observed for K in the leaf and stalk tissues. For Ca, Mg, Fe, Mn, Zn, Cu, and Na, it was not possible to establish the influence of maize selection. The C/P ratio of leaves and stalks underwent influence of the technological level with high values for simple hybrids. Maize selection seems to decrease P and K concentration for two major residue fractions, leaves and stalks.