Potentialit:y of the aphid parasitoid species, Lysiph/ebus
testaceipes (Cresson) (Hymenoptera: Aphidiidae) against
three species of aphids was studied. All biological studies of
the parasitoid on its host, Rhopalosiphum pad! (L.) were also
studied under laboratory conditions. Developmental periods
were estimated on R. pad,, Aphis cra cci vo ra Koch. and
Sc/v2’aphis graminum Rond.. Number of ovarian eggs, total
number of eggs laid and number of mummies! female of L.
testace,pes when parasitized R. pad! were estimated as
164±41.08 and 43.85±20.22 (eggs! female) and
34.23±13.74 mummies! female, respectively. Respective
percentages of adults’ emergence and sex-ratio were 61.62%
and 1:1.12 (female: male). Shortest longevity was recorded
when the adults were starved. Life table studies showed that
the intrinsic rate of increase for R. pad! was faster than that
of its parasitoid on R. pad Host preference indicated that the
parasitoid preferred S. gram!num, followed by R. pad! and
then A. cracc!vora.
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