Developmental time for immature stages of
T.
pupivorus is summarized in Table 1.
Total developmental time from egg to adult emergence was 14.0 days. The duration of egg and larva periods were 1.3 and 6.7 days, respectively. The pupal development lasted an average of 6.0 days. Although
T.
pupivorusis a potential biological control agent to control
O.
arenosella (NorAhya et al., 2019, Le et al., 2020), limited data on the developmental biology of
T.
pupivorus on
O.
arenosella are available. The present study indicated that total developmental time from egg to adult emergence of
T.
pupivorus was ranged from 13-15 days. Our results are in agreement with the results of
Ghosh and Abburahiman (1985) who reported that developmental times for immature stages of
T.
pupivorus on
O.
arenosella was 13-15 days.
The females produced a mean of 124.2 eggs during an average lifespan of 9.4 days (Table 2).
Longevity of the female (9.4 days) was longer than that of the male (2.8 days). While the pre-oviposition period lasted for 2.5 days after emergence, the females stopped laying eggs (post- oviposition) about an average of 4.1 day before death. The fecundity of
T.
pupivorus on
O.
arenosella was higher than the results of Nor
Ahya et al., (2020) who reported that fecundity of
T.
pupivorus rearedon
O.
arenosella with 30% honey at 30°C was 105.4 progenies. However, female longevity (9.4 days) was longer than that was recorded by
Ghosh and Abburahiman (1985) (5.0 days) and
NorAhya et al., (2020) (6.0 days).
The number of progenies emergence from a single pupa of
O.
arenosella was 103.8 in average with a range of 28-161 (Table 3).
Ghosh and Abburahiman (1985) also reported that the number of eggs laid on a single
O.
arenosella was 22-162 days. The offspring sex ratio (8.0%) was female-biased (Table 3). There was no other information on the offspring sex ratio of
T.
pupivorus to be a comparison. However female-biased sex ratio of
T.
pupivorus is similar with other eulophid parasitoids
(Tran and Takagi, 2006).
Because laboratory rearing
O.
arenosella on coconut leaves is laborious, a maintain of
O.
arenosella on large scale on natural host (
e.g. coconut leaves) is not possible to supply insect hosts to a mass-rearing of the parasitoid
T.
pupivorus.
Murthy et al., (2002) indicated that an artificial diet reared
O.
arenosella can be used for mass rearingthe parasitoid
B.
nephantidis without depending on the natural host, plant host and factitious hosts. Moreover, previous studies reported that
Galleria mellonella L. (Lepidoptera: Galleridae) was a potential alternative host for the rearing of
Goniozus nephantidis Muesebeck (Hymenoptera: Bethylidae), a larval parasitoid of
O.
arenosella (Mohan and Shameer, 2003;
Venkatesan et al., 2007) Therefore, those alternative rearing systems can be used for a mass rearing of
T.
pupivorus. While previous studies have indicated that biology of an insect parasitoid depends on abiotic and biotic factors including temperature, relative humidity and host available
(Tran et al., 2007; Tran et al., 2012), suitability of
T.
pupivorus reared with artificial diet and alternative hosts as well as temperature dependent development of
T.
pupivorus are needed further studies.
