THE EFFECT OF B-CHROMOSOME ON MATING SUCCESS OF THE GRASSHOPPER EYPREPOCNEMIS-PLORANS

The mating ability of E. plorans was tested in laboratory conditions i n six experimental units composed of ten males and fifteen females dur ing 31 days. When significant differences were found (three from the s ix cages, and in totals) they involved a decrease of matings involving males with B chromosomes. The same tendency seems to exist in females , but to a lesser extent, so that a significant effect is only detecte d when the totals are considered. Accessory chromosomes also delay, in both sexes, the occurrence of the first mating. No mating preferences depending on the number of Bs were detected.