To produce the subject grain capable of suppressing the leakage of an agrochemical ingredient a fixed time release type coated agrochemical during the initial release suppressing period thereof and further making the release rate of the agrochemical ingredient of a linear release type coated agrochemical constant and useful as a core material of the coated agrochemical granule by including the agrochemical ingredient and regulating the disintegration ratio within a specific range.

This grain is obtained by including (A) one or more kinds of agrochemical ingredients {e.g. 1,2,5,6-tetrahydropyrrolo[3,2,1-ij]quinolin-4-one} and further preferably including (B) bentonite and (C) a hydrophilic binder such as polyvinyl alcohol and thereby regulating the disintegration ratio of the granule after undergoing the shaking destroying treatment to 0.001-2%. The content of the ingredient B is preferably 20-80 wt.% based on all the ingredients and the content of the ingredient C is preferably 1-5 wt.% based on all the ingredients. The grain is produced by an extrusion granulating method, etc., and preferably has 0.7-5.0 mm grain diameter.