SEX AND CROSSING OVER IN LINKAGE GROUP III OFTRIBOLIUM CASTANEUM

Abstract

The relative position of the genes black (b), light ocular diaphragm (lod) and aureate (au) for the 3 linkage group of T. castaneum (Herbst) (Coleoptera, Tenebrionidae) was determined as b - lod - au. The distances between the various genes vary, depending on the cross. The b++/+ lod au .female. .times. + lod au/+ lod au .male. crosses give the following recombination values: au - lod = 18.32 .+-. 1.21%; b - lod = 21.05 .+-. 1.51% and b - au = 37.43 .+-. 1.27%. The reciprocal crosses give au - lod = 27.67 .+-. 1.62%; b - lod = 13.97 .+-. 1.26% and b - au = 39.79 .+-. 1.78%. For the larger distances encompassed in the b - au region the recombination values in the 2 sexes were not significantly different. For the shorter b - lod region the recombination values were significantly larger in the females than in the males, while for the adjacent lod - au region the opposite was true. The main factors contributing to these sex differences in recombination may be the modifiers which are different in the genetic background of the 2 sexes.