THE TRANSFER OF PYRETHROID RESISTANCE RESULTING FROM CROSSES BETWEEN RESISTANT GERMAN COCKROACHES AND SUSCEPTIBLE ASIAN COCKROACHES

Crosses were made between the Asian cockroach, Blattella asahinai Mizu kubo, and resistant strains of the German cockroach, B. germanica (L.) , to assess the transfer of pyrethroid resistance to the progeny and t o study the inheritance mechanism(s) involved. It was shown that the s train of Asian cockroaches studied was susceptible to four pyrethroids . F-1 progeny were essentially susceptible to the same compounds. Test s with F-2 progeny and those from backcrosses to the resistant parent indicated that the data for each pyrethroid fit an hypothesis of simpl e, autosomal, nearly completely recessive inheritance. The results are discussed from the standpoint of the impact of the Asian genome on th e inheritance mechanism(s).