Baermann method, while that of M. incognita and M. hapla from 0.6 to 713 J2 equivalent (J2eq)/20 g soil and from 0.0 to 115 J2eq/20 g soil, respectively, with the real-time PCR method. The yield was determined by the sum of commercial sized eggplants harvested for 3 months of the cultivation period. The yield decreased in the plots with an initial population of RKNs more than 2 J2/20 g soil with the Baermann method. In real-time PCR, the yields were low in the plots with the sum of initial M. incognita and M. hapla more than 128 J2eq/20 g soil. The present study established a quantification method with real-time PCR for M. incognita and M. hapla in andosol and evaluated the relationship between the initial population of Meloidogyne spp. and the yield of eggplant. Nematol. Res. 43(2), 21-29 (2013)