The control effects of applying a solid-type material (carrier: PVA and agar) B. pilosa var. radiata extract onto root-knot formations of M. incognita and M. hapla were evaluated. It was clear, in particular, that the highest controlled effect of the planting hole treatment (bottom side) of the cube-type material, occurred where the rates of agar and plant extract dry matter were 1:3. Furthermore, the control effect of cube-type materials (1:3) on M. hapla was high when the amount of sprinkling water was increased, compared with that used regularly, and no influence on the growth of tomatoes was observed. As a result, the B. pilosa var. radiata extract materials could be used as an environmentally-friendly control agent for M. incognita and M. hapla.