THE PERSISTENCE OF CERTAIN PESTICIDES IN THE SOIL AND THEIR EFFECT ON CROP YIELDS

Abstract

From 1954 to 1958 at Kentville, Nova Scotia, the persistence and residual effects of certain pesticides, added to the soil annually from 1949 to 1953 inclusive, were investigated. Stability of pesticides in the soil rated in descending order of persistency was as follows: arsenic, DDT, BHC, chlordane. Arsenic, DDT, and sulphur caused decreases in the yields of some crops. Evidence indicated that DDT, BHC, and parathion were translocated to root crops. Increased concentrations of arsenic in the soil resulted in increased accumulations of the element in plants.The use of lime in the soil did not ameliorate the toxic conditions resulting from the arsenic and DDT treatments, but did correct the effects of sulphur applications.