The name is absent

Singh and Singh

(correlation coefficient between density and remating frequency: cross 4, r =
0.974, df=2, P < 0.05; cross 5, r = 0.989, df=2, P < 0.05). Female remating
frequency was tested at four densities employing ct rb mutant females with
y and ct rb mutant males in crosses 6 and 7. In both these crosses there are
significant increases in the frequency of female remating at higher densities
(correlation coefficient between density and remating frequency: cross 6,
r =0.983,df=2, P < 0.05; cross 7, r =0.998,df=2, P < 0.01).

The contingency χ² test, to test the variation between remated and not-
remated females, shows nonsignificant variation for wild-type females (cross
1, 2-h daily observation design; Table II). However, the χ² test for contin-
gency for crosses 3 to7 shows significant variations in both designs (Table II).

DISCUSSION

During the course of this study, experiments were conducted to inves-
tigate the effect of density on female remating frequency by employing dif-
ferent wild-type and mutant strains of D. ananassae. It is evident from the
present results that all strains tested during the present study show a signifi-
cant dependence of remating frequency on density under both the 2-h daily
observation design and the continuous confinement design, except in a wild-
type (Bhutan) strain which shows no dependence of remating frequency on
density.

In female remating studies two experimental designs have been used by
various investigators and the female remating frequency varies considerably
in different species, i.e., the periodic confinement design and continuous
confinement design (Pyle and Gromko, 1978; Loukas et al., 1981; Markow,
1985; Aspi, 1992; McRobert et al., 1997). The periodic confinement (brief
duration of male-female interaction) is correlated with a low incidence of
remating (Manning, 1962) and the continuous confinement is correlated with
a high frequency of remating (Lefevre and Jonsson, 1962; Pyle and Gromko,
1978). During the present study, it has also been observed that the frequency
of female remating is higher in the continuous confinement design compared
to the periodic confinement design. Thus our results support the statement
that a brief duration of male-female interaction is correlated with a low
incidence of remating, and continuous confinement (longer duration of male-
female interaction) is correlated with a high frequency of remating.

The relationship between density and frequency of multiple mating was
examined using two experimental designs, i.e., periodic (2-h daily) and con-
tinuous confinement, in D. melanogaster by Gromko and Gerhart (1984).
They found that increased density per se inhibits rater than facilitates remat-
ing. In the present study same experimental designs used by Gromko and

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