Genotype and liming impacts on boron and molybdenum status in maize

Abstract

Liming experiment with hydrated lime (73% CaO + 2-3% MgO + 21% water) in the amounts 0, 5 and 20 t ha-1 was conducted in spring 2006. Six domestic maize hybrids (B1 = Os298P, B2 = Tvrtko303, B3 = Os444, B4 = Os499, B5 = Os552 and B6 = Os596) were sown at beginning of May (basic plot 24 m2). The ear-leaf of maize was collected at flowering and grain in maturity of the 2006 and 2007 growing seasons. Boron and molybdenum in the samples were determined by the ICP-OES method. The growing season 2006 was favorable for maize growth, while 2007 characterized stress due to drought and high air-temperatures. B and Mo concentrations (2-yr means) in grains were considerably lower for 12-fold (B) and close to two-fold (Mo) in comparison with the leaves. Leaf-Mo in 2007 was about 50% lower in comparison with 2006 (0.310 and 0.149 mg Mo kg-1, respectively). Mean differences among the hybrids (mg kg-1) were as follows: leaf-B 9.3 (B1) to 21.4 (B3) and grain-B 1.00 (B2) to 1.50 (B3); leaf-Mo 0.157 (B5) to 0.361 (B3) and grain-Mo 0.109 (B5) to 0.137 (B1). As affected by liming leaf-Mo were increased compared with the control 2.5-fold and 4.1 fold, grain-Mo 3.8-fold and 4.6-fold, for 5 and 20 t ha-1 lime, respectively. Liming effects on B concentrations in maize were considerably lower, because non-significant differences for leaf-B in 2006 and decrease for 36% in 2007 were found.