Abstract: A process for breeding a Manila clam pedigree, includes: directively breeding present Manila clam pedigrees having different shell shapes to obtain a shell shape pedigree (A) having best phenotypic character; directively breeding the shell shape pedigrees (A) from different geographical populations to obtain a geographical population pedigree (B) having best phenotypic character; directively breeding the geographical population pedigrees (B) having different shell colors to obtain a growth shell color pedigree (C) of fastest growth and a resistance shell color pedigrees (E) of highest stress resistance; hybridizing the growth shell color pedigree (C) and the resistance shell color pedigree (E) to obtain a first hybridied pedigree (F1) of faster growth and higher stress resistance than the present Manila clam pedigrees; and directively breeding the first hybridied pedigree (F1) to obtain a second hybridied pedigree (F2) maintaining faster growth and higher stress resistance than the present Manila clam pedigre

Abstract: A process for polycross breeding a Manila clam pedigree, includes: providing present Manila clam pedigrees of different shell color types as parents; ecologically maturing the parents; reciprocally hybridizing the parents by every two of different shell color types to obtain offsprings thereof; nurturing the offsprings until gonads thereof mature synchronously; and hybridizing the matured offsprings with each other to obtain at least a four-way cross pedigree accumulating all valuable genes of the parents.