In order to reduce the use of pesticide and the environmental damage of pesticide, starch-based pesticide sustained-release materials and starch-free polymers were synthesized by 60Co γ-ray irradiation. The rotational viscosity, degradability and the sustained-release effects of pymetrozine were studied. The degradability of starch-based material is better than that of starch-free polymers and the pymetrozine sustained-release effect is better than that of attapulgite and starch constrast. At 5 minutes, the pymetrozine release percentage of blank sample was more than 90%, that of attapulgite or starch constrast was more than 50%, and that of starch-based materials was in the range of 10%~20%. At 20 minutes, the pymetrozine release percentage of blank sample was more than 99%, that of attapulgite or starch constrast were more than 85%, and that of starch-based materials was 51%~62%. [ABSTRACT FROM AUTHOR]