Genotype and liming effects on cadmium concentration in maize (Zea mays L.)

Abstract

Liming experiment with hydrated lime (73% CaO + 2-3% MgO + 21% water) in the amounts 0, 5.0 and 20.0 t ha -1 was conducted in spring 2006 on acid soil. Each plot of liming (414m 2) was divided in four sub-plots for receiving four replicates in level of the genotype. Six domestic maize hybrids (Os298P, Tvrtko303, Os499, Os444, Os596 and Os552) originating from Agricultural Institute Osijek was sown at beginning of May (basic plot 24 m 2). The ear-leaf samples of maize were collected at flowering and grain in maturity stages. Mean grain yields of maize in the experiment were 11.63 and 4.83 t ha -1, for the 2006 and the 2007 growing season, respectively. Unfavorable weather characteristics in 2007 were main responsible for yield loss. Yield differences between liming treatments and the control were in both years non-significant. Liming effects on decreasing leaf-Cd in maize was found in both years (2-year means: 0.095 and 0.066, for the control and mean of two liming treatments, respectively). Considerable difference of leaf-Cd was found among the maize hybrids and it was in range from 0.040 to 0.160 mg Cd kg -1. Two hybrids (Os298P and Tvrtko 303) separated from remaining four hybrids by the higher leaf-Cd (2-year means 0.141 and 0.043 mg Cd kg -1, respectively). However, these differences are responsible for possible harmful dietary effects only in case of using these hybrids as silage maize because grain-Cd in maize was considerably lower (under detectable range = <0.02 mg Cd kg -1) and without effects on food contamination.