Abstract:
Piezodorus guildinii
(Hemiptera: Pentatomidae) is an important soybean
pest, and one
of its main natural enemies is
Telenomus podisi
(Hymenoptera: Platygastridae). Rearing
of the parasitoid is constrained by the hosts' egg
quality, which deteriorates after few
generations in laboratory, therefore, cold-stored h
ost eggs utilization could be a useful
tool for augmentative biological control. Thus, the
objective was to evaluate the quality of
P. guildinii
cold-stored eggs, on the performance of parental a
nd F
1
generation of
T.
podisi
. Host
eggs 24 hour old were stored at -18°C for one (N= 53
), two (N= 28) or three
months (N= 29), and approximately 40 host eggs were
offered to a
T. podisi
female per
treatment, for 48 hours. The control treatment cons
isted of 24-hour-old non-frozen host
eggs, obtained and kept at 24°C (N= 55). Parental ge
neration parasitism and progeny ́s
emergence on frozen eggs was significantly lower th
an on non-frozen eggs, even for the
shorter storage period. Male proportion and preimag
inal development time of the
progeny increased with freezing period. However, pa
rasitism proportion caused by adults
of F
1
, and emergence, male proportion, and preimaginal d
evelopment time of F
2
were not
affected. Although the performance of
T. podisi
on frozen
P. guildinii
eggs was
significantly lower than on nonfrozen ones, host eg
gs storage for up to two months
allowed obtaining a parasitism rate of 40%
with a high emergence rate. This could be
helpful enough to maintain mass rearings, mainly du
ring the host hibernation period, and
to enhance field parasitism when host is scarce.
Keywords
: Host storage, Mass-rearing, Parasitoids.
