Spraying of spring wheat plants during vegetation with herbicides of 2,4-D group and ethrel increased chromosome aberrations in meiosis 2.8-5, 3.6-4.1 times. The insecticides, chlorophos and phtalophos, in a little higher dosage than it is usually practised increased the spontaneous level of chromosome aberrations 3.1-5.5 times. Phtalophos also induced chlorophyll mutations. These results testify to the necessity of keeping strictly to the established normative doses, because of overdosage is of potential genetic danger to spring wheat crops.