engleski

Influence of potassium chloride on yield and nutritional status in corn hybrids

Six corn (Zea mays L.) hybrids (OsSK 377 ; OsSK 382 ; OsSK 407 ; OsSK 552 ; OsSK 644 and Bc 66- 61) were grown on strong K-fixing soil during the growing season 1993. Increased K fertilization in KCl form was applied in spring of 1990 to level of 3250 kg K2O ha-1. Four rates were used for testing corn hybrids response (150, 1000, 1900 and 3250 kg K2O ha- 1). Response of corn to K fertilization was very pronounced: grain yields were in range from 1.83 t h-1 (150 kg K2O ha-1) to 7.04 t ha- 1 (3250 K2O ha-1). Differences of grain yields among corn hybrids were from 4.35 t ha-1 (Bc 66-61) to 5.31 t ha-1 (OsSK 407). Significant differences of nutritional status among the hybrids were found as follows (mg kg-1): 18.9- 26.5 (zinc), 14.4-17.4 (manganese), 120-144 (iron) and 18.2-23.2 (copper), respectively. Zinc status in corn leaves was independent on applied fertilization, while the concentration of manganese, iron and copper was significantly decreased by application of the highest KCl rate (mg kg-1: 17.4 and 12.6 Mn, 150 and 120 Fe, 21.5 and 18.5 Cu, for the control and 3250 kg K2O ha-1, respectively). As affected by KCl fertilization there were found considerable differences in K and Mg status of corn leaves as follows: 0.31% K (acute K deficiency) and 1.18% K, as well as 1.08% Mg and 0.47% Mg, for the control and 3250 kg K2O ha-1, respectively.

corn ; yield ; hybrids ; fertilization ; potassium ; magnesium ; zinc ; manganese ; iron ; copper ; ear-leaf

nije evidentirano