42 N. Veena and D. Manjunath
days was observed with big parasitoid females
in comparison with the smaller ones (9.70 ± 0.23
days) (Fig. 1 ).
No significant variation in the rate of para-
sitism of host puparia by Trichopria sp. was
noticed when the puparia of 1–8 day-old (at an
age difference of 1 day) were offered, with the
results among the treatments varying between
2.00 ± 0.00 (1, 2, 4, and 7 day-old) to 1.90 ± 0.10
(3, 5, 6, and 8 day-old). The parasitoid’s life cycle
too revealed statistical similarity among the treat-
ments. Considering the male, female, and total
progenies produced by parasitoid females of
different ages, the values for these parameters
decreased almost gradually and consistently
with increase in female age (Table 2 ). Statistical
analysis of data revealed that the total progenies
produced by 1 (204.80 ± 1.61) and 2 day-old
(222.20 ± 1.65) females of Trichopria sp. were
significantly superior to other treatments with the
values 187.50 ± 9.90–159.90 ± 1.25 being at par
with each other. The data for sex ratio of the par-
asitoid progenies generated from the females of
different ages ranged between 1.51 ± 0.02 (1 day-
old) and 1.09 ± 0.03 (6 day-old) without showing
significant variation.
The impact of the female size of Trichopria sp.
on its progeny production was assessed by allow-
ing 2 day-old big and small parasitoid females
to parasitize 3 day-old puparia of E. bombycis at
1:4. It can be understood that the performance of
big parasitoid females has been superior to small
females with respect to most parameters related
to progeny production. The superiority of the big
parasitoid female has been found with respect to
the number of puparia parasitized and progeny
production that included males, females, and the
total population. Obviously, the higher efficiency
of big females in terms of the rate of parasitism
and progeny production can be considered as at-
tributes associated with parasitoid fitness/quality.
Big parasitoid females parasitized nearly 50 %
more host puparia than small females. Similar
effect was noticed with regard to total progeny
produced by big females. Though both big and
small parasitoid females have revealed an identi-
cal sex ratio in the progenies, significant increase
in the rate of parasitism of host with concomi-
tant enhancement in the progeny production,
including females, underlines the importance of
parasitoids in effective parasitism. Enhancement
in female progeny production by big parasitoid
females following parasitism of more number of
host puparia can be considered advantageous for
biological suppression.
Large parasitoid females of Aphytis melinus
and Aphytis Lignanensis (Opp and Luck 1986 ),
Diglyphus begini (Heinz 1991 ), A. minuta (Viss-
er 1994 ), and A. kamali (Sagarra et al. 2001 ) were
found to be more fecund than small females. In
addition, big females produced more female
progenies in Dinarmus basalis (Waage and Ming
1984 ), Trichogramma sp. (Waage and Ng 1984 ;
Greenberg et al. 1998 ), Trichogramma pretiosum
(Kazmer and Luck 1995 ) and Anisopeteramulus
calandrae (Ji et al. 2004 ). The findings of the
present investigation with Trichopria sp. are in
consonance with those of the above investiga-
tors. But, these authors have not presented any
account of the sex ratio of the parasitoids studied.
Admittedly, they have gathered information on
female longevity and host searching efficiency/
host encounter, with big parasitoid females scor-
ing over small females with reference to these
parameters. Observations related to the influ-
ence of parasitoid female size on the sex ratio of
progenies are scanty. Nevertheless, Sagarra et al.
( 2001 ) recorded that the sex ratio of progenies
produced by small females of A. kamali was
higher than that in the progenies of big females.
Our results differ from those of the above authors
(Sagarra et al. 2001 ), with the sex ratio being
higher in the progenies produced by big females
of Trichopria sp.
/RQJHYLW\ 'D \V %LJ
6PDOOFig 1 Impact of size of Trichopria sp. female on its lon-
gevity; data are the means of 10 replications (mean ± SE).
**Significant at 1 %