Impact of Foliar Application of Various Forms of Silicon on the Chemical Composition of Sugar Beet Plants

Abstract

The effect of marine calcite, a mixture of ortho- and polysilicic acid as well as orthosilicic acid applied as a foliar spray on the chemical composition of sugar beet leaves in the critical phase of nutrient supply (beginning of July) but also leaves and roots during harvest time in 2015–2016, was studied. The content of silicon in the leaves ranged from 1.24 to 2.36 g kg−1 d.m. at the beginning of July, 3.85–5.34 g kg−1 d.m. during harvest and 2.91–4.20 g kg−1 d.m. in the roots. The foliar application of silicon caused a significant increase in the content of magnesium and calcium in leaves (in July) as compared to the control. The sugar beet consumes approx. 75 kg Si ha−1, which is almost 3.5 times more than P and 20% more than Mg thus proving its importance for its species. About 70% of the silicon taken up by sugar beet is stored in roots and 30% in leaves. The pure sugar yield is most favorably influenced by two- and threefold foliar application of the product containing silicon in the form of orthosilicic acid stabilized with choline, and a threefold mixture of ortho- and polysilicic acid. The increase in the pure sugar yield is not the result of a change in the chemical composition of sugar beet plants, but their more efficient functioning after foliar application of silicon under stress conditions caused by water shortage.