Adsorption of polyhedra of a cytoplasmic-polyhedrosis virus by soil particles

Tests on the quantitative adsorption of polyhedra of a cytoplasmic-polyhedrosis virus of Bombyx mori to soil showed an increase in the adsorption of polyhedra with an increase in the amount of soil, but the number of polyhedra adsorbed per unit weight of soil decreased. The number of polyhedra adsorbed to a fixed quantity of soil was in direct proportion to the polyhedron concentration, and the amount of adsorption increased with acidity but decreased with the addition of reagents which masked the polyvalent cations exposed on the surfaces of soil particles. The polyhedra applied to the top of a soil column were detected microscopically within 4 cm from the surface after the equivalent of 1,120 cm depth of water was passed through the column. The polyhedra occurred on the upper surface of the soil column and on the walls of voids formed by random packing of the soil particles.