[Construction of linkage localization lines containing genes with maternal effects].

Since the phenotypes of hybrid progenies involving genes with maternal effects are affected by the genotype of female parent, they cannot reflect the genotypes of individuals. This makes it difficult to develop test cross parents (triple or double recessive lines) for linkage localization and, consequently, hinders the progress in localization researches for these types of genes. In this study, we designed a set of hybridization schemes, the key of which was to make the "maternal-effect" genes homozygous at first, and then the non-maternal-effect genes. Using this scheme, we successfully produced a triple recessive line for genes ch (chocolate), nlw (non-lepis wing) and b-t (maternal brown egg of Tsujitan) on the 13th linkage group and a double recessive line for genes nb (narrow breast) and ki-2 (kidney-shaped egg 2) on the 19th linkage group of Bombyx mori.