Silicon availability of the nursery bed soils and effects of silicon fertilizer applied on the growth and silicon uptake of riceOryza sativaL. seedlings

Abstract

(pp. 41–46) Silicon availability in 36 commercial nursery bed soils was evaluated by four methods the phosphate buffer (pH 6.2, 40 mmol L−1), incubation, supernatant and acetate buffer (pH 4.0, 1 mol L−1) Methods. The influence of silicon availability in the nursery bed soils on the silicon uptake of rice Oryza sativa L. cv. Hitomebore seedlings and the effect of silicon fertilizer application were examined in a glass house in 2002. The results revealed that the best correlation between silicon content in rice seedlings and available silicon in soils was obtained with the phosphate buffer‐solution method (r = 0.86). More precise evaluation of available silicon was achieved by grouping soils based on these phosphate absorption coefficients (PAC). The correlation coefficients between silicon content in rice seedlings and available silicon in soils were 0.92 and 0.72 for volcanic soils (PAC > 1500) and non volcanic soils (PAC < 1500), respectively. We concluded that the phosphate buffer method is the most easily adjusted method for estimation of silicon availability in nursery bed soils, and silicon fertilizers should be applied when silicon availability in non‐volcanic nursery bed soils goes below 200 mg kg−1, whereas the level is less than 350 mg kg−1 in volcanic soils.

A contemporary overview of silicon availability in agricultural soils

“…In some cases phosphate has been added to the Na‐acetate extractant in order to displace more adsorbed silicate from adsorption surfaces ( Fox et al, 1967). In this regard, Heinai and Saigusa (2006) successfully used a phosphate buffer extraction (Na 2 HPO 4 ) to displace adsorbed Si for soil testing in paddy rice.…”