Consider about soil treatment chemicals..1.Complete control of the plant disease is obtained.2.Complete control of the plant disease is not obtained.3.The fungal disease is suppressed by the chemical.4.The fungus always killed by the chemical.5.Nematicides destroy the nematodes but eggs escape.

Plant pathology is the science that studies the causes of plant diseases, the mechanisms by which diseases develop in individual plants and in plant populations, and the ways and means by which plant diseases can be managed or controlled.