Poljoprivreda (Jun 2003)
INFLUENCES OF SOIL AND GENOTYPES ON MICRONUTRIENTS STATUS IN MAIZE PLANTS
Abstract
Ten corn hybrids were grown on two soil types of Drava Valley in Slatina area (alluvial soil and pseudogley) during two growing seasons (1998 and 1999). The ear-leaf at the beginning of silking stage was taken for chemical analysis. Micronutrient concentrations in corn leave samples were measured by ICP-AES after their microwave digestion using concentrated HNO3+H2O2. Mobile fraction of these elements in soils was also determined by ICP-AES after their extraction by ammonium acetate-EDTA. In both year of the testing, corn yields on acid soil were about 25% lower in comparison with alluvial soil. Mean concentrations of tested elements in corn leaves found in our investigations (mg kg-1 ) were 30.4 (Zn), 129.4 (Mn) and 190.0 (Fe), respectively. In general, significant influences of growing season, soil type and genotype on Zn, Mn and Fe status in corn were found. For example, in the first year of testing higher Zn and Mn were found, as well as lower Fe concentrations in comparison with the second year. Corn growing on alluvial soil occurred due to lower Zn and Mn as well as higher Fe concentrations in plants compared to growing on pseudogley. However, these findings are not in coincidence with status of mobile fractions of Zn and Mn in the experimental plots. We presume that pH value near to neutral on alluvial soil could be responsible factor because low availability of Zn and Mn for plants occured under these conditions. An important role of heredity factors on Zn, Mn and Fe status in corn was found in our study because differences among the hybrids (mean values for two growing seasons and two soil types) under identical environmental conditions were in ranges (mg kg-1) from 26.8 to 36.0 (Zn), from 98.6 to 150.4 (Mn) and from 168.2 to 222.4 (Fe), respectively. It is very indicative that the first-ranged hybrid concerning grain yield (OsSK458exp: 12.34 t ha-1 ) is in the group characterizing low concentrations of Zn, Mn and Fe in leaves.