SYNERGISTIC INTERACTION BETWEEN SECOND AND THIRD CHROMOSOMES ON VIABILITY OF <i>DROSOPHILA MELANOGASTER</i>

Effects of chromosomal interaction on male mating activity in Drosophila melanogaster.

“…To evaluate the nature and the magnitude of interchromosomal interaction in male mating activity, two indices were employed: i statistic used by Spassky et al (1965), Temin et al (1969) and Kosuda (1971), and k statistic devised and used by Seager and Ayala (1982) and Seager et al (1982). i is defined as i =1 -observed mating activity/expected mating activity .…”

“…i is rewritten as i =1-wXYz/WxyZ, where W, X, Y, Z are the male mating activity in heterozygous condition (F=0) and w, x, y, z are the mating activity in homozygous condition (F =1) of Cy; Ubx, Ubx, Cy and wild type, respectively (Table 1). I statistic used in Kosuda (1971) can be replaced by I =1-i.…”

“…To extend our understanding of the fitness function, a large body of experiment has been carried out for various fitness components (Dobzhansky et a1.1963;Malogolowkin-Cohen et a1.1964;Spassky et a1.1965;Crow 1968;Mukai 1969;Temin et al 1969;Kosuda 1971Kosuda , 1972Kosuda , 1980Clark and Feldman 1981;Sharp 1984;Seager and Ayala 1982;Seager et al 1982). It has become apparent that the male reproductive component of fitness may play a more important role than fitness variables in preadult stages and female fertility , in estimating the net fitness differentials in Drosophila (Anderson 1969;Sved and Ayala 1970;Bundgaard and Christiansen 1972;Marinkovic and Ayala 1975a, b;Petit et a1.1980;Brittnacher 1981;Sharp 1984;Kosuda 1983).…”

THE EFFECT OF MUTAGENESIS ON COMPETITIVE ABILITY IN DROSOPHILA

“…The assumption of independence of new mutations is probably not unreasonable as an approximation. New mutations in Drosophila usually fail to show appreciable epistasis (Mukai and Yamazaki, 1968;Temin et aI., 1969;Kosuda, 1971;Mukai et aI., 1972;Mitchell and Simmons, 1977;Ohnishi, 1977aOhnishi, , 1977. The very weak epistasis observed for new mutations in some experiments (Mukai 1967(Mukai , 1969) is consistent with that expected under pleiotropy and multiplicative fitness (Rose, 1982).…”

The estimation of epistasis in components of fitness in experimental populations of Drosophila melanogaster II. Assessment of meiotic drive, viability, fecundity and sexual selection

“…Several attempts to detect epistasis in viability of wild chromosomes of Drosophila have been made by analysing progeny ratios from crosses which yield flies isogenic for the second chromosome, the third chromosome or co-isogenic for both (Spassky eta!., 1965;Temin eta!. 1969;Kosuda, 1971;Tsuno, 1970). The general conclusion of these studies is that the double homozygote viability is slightly lower than expected from the single homozygote fitnesses, i.e., there is positive epistasis, although Temin eta!., (1969) found the epistasis to be insignificant.…”