history parameters. It seems that reproduction is more sensitive than the other fitness
components to environmental variables. For example, 136.4, 85.4 and 36.2 daughters per a female T. grandis were recorded during a generation in researches of AmirMaafi (2000), Bazavar et al. (2015) and Nozad-Bonab et al. (2014) respectively. The
same parameter was estimated as 198 and 63 for O. fecundus in studies of
Ahmadpour et al. (2013) and Bazavar et al. (2015) respectively, 76–82 for
O. telenomicida (Rafat et al. 2013), 130 for T. semistriatus (Asgari et al. 2001),
167–216 for T. vassilievi (BenaMolaei 2014) and 20–40 for T.djadetshkoe (Abdi
2014). The highest recorded value for total fecundity is 355.5 eggs for O. fecundus
(Ahmadpour et al. 2013), but a low value for sex ratio (0.55) caused R 0 fall within
the range of T. vassilievi in BenaMolaei’s (2014) study. Total fecundity of the recent
species was 180–280 progenies per female with a strong female biased sex ratio of
0.8–0.95. The sex ratio of sunn pest’s egg parasitoids generally is female biased and
often exceeds 0.7, but the least value was recorded for T. djadetshkoe and
O. fecundus with 0.57 and 0.55 respectively. The GRR value is often closely related
or even is equal to R 0 because survivorship curves of these parasitoids generally are
convex (Type I) and mortality occurs mainly at senescence.
Development and therefore generation time are very homoscedastic variables
among life-history parameters. The difference between individuals and hence variance of these variables is negligible. Some external factors like temperature, however (see Sect. 8.5.3) can create large discrepancies among treatments. Nevertheless,
within-group variation is always small. Hence, these are good indicators for quality
control and comparing physical, nutritional and other rearing conditions. Development time is sensitive to temperature and always shorter in males (protandry).
Therefore, a comparison among species is possible only at the same temperature
and optimum temperature of 25–26
C will be recommendable due to the convergence of developmental rate in different treatments. It means that effect of external
factors such as host quality etc. minimizes (Nozad-Bonab and Iranipour 2013).
Development time was 9.6 Æ 0.07 for T. grandis disregarding gender (NozadBonab et al. 2014), 13.5 Æ 0.1 for males and 14.6–15.0 Æ 0.04 for females of
T. vassilievi (Iranipour et al. 2015), 15–16 days for T. djadetshkoe (Abdi 2014),
14.4 Æ 0.17 for O. telenomicida (Rafat et al. 2013) and 13.4 Æ 0.05 for males and
14.2 Æ 0.06 d for females of O. fecundus (Ahmadpour et al. 2013). Small value of
SE in all studies is very interesting. Generation time differs between 10–21 days in
different species at similar temperature regims.
8.5.1.2 Effect on Foraging Behaviour
Searching efficiency, handling time and maximum attack rate are functional
response parameters that may represent the efficiency of a parasitoid, predict density
dependence and also can use for calculating number of parasitoids required for
release. Numerical and aggregation studies also may enhance our knowledge
about the results of release.
8 Superfamily Platygastroidea: Natural Enemies of True Bugs, Moths, Other. . .
315
components to environmental variables. For example, 136.4, 85.4 and 36.2 daughters per a female T. grandis were recorded during a generation in researches of AmirMaafi (2000), Bazavar et al. (2015) and Nozad-Bonab et al. (2014) respectively. The
same parameter was estimated as 198 and 63 for O. fecundus in studies of
Ahmadpour et al. (2013) and Bazavar et al. (2015) respectively, 76–82 for
O. telenomicida (Rafat et al. 2013), 130 for T. semistriatus (Asgari et al. 2001),
167–216 for T. vassilievi (BenaMolaei 2014) and 20–40 for T.djadetshkoe (Abdi
2014). The highest recorded value for total fecundity is 355.5 eggs for O. fecundus
(Ahmadpour et al. 2013), but a low value for sex ratio (0.55) caused R 0 fall within
the range of T. vassilievi in BenaMolaei’s (2014) study. Total fecundity of the recent
species was 180–280 progenies per female with a strong female biased sex ratio of
0.8–0.95. The sex ratio of sunn pest’s egg parasitoids generally is female biased and
often exceeds 0.7, but the least value was recorded for T. djadetshkoe and
O. fecundus with 0.57 and 0.55 respectively. The GRR value is often closely related
or even is equal to R 0 because survivorship curves of these parasitoids generally are
convex (Type I) and mortality occurs mainly at senescence.
Development and therefore generation time are very homoscedastic variables
among life-history parameters. The difference between individuals and hence variance of these variables is negligible. Some external factors like temperature, however (see Sect. 8.5.3) can create large discrepancies among treatments. Nevertheless,
within-group variation is always small. Hence, these are good indicators for quality
control and comparing physical, nutritional and other rearing conditions. Development time is sensitive to temperature and always shorter in males (protandry).
Therefore, a comparison among species is possible only at the same temperature
and optimum temperature of 25–26
C will be recommendable due to the convergence of developmental rate in different treatments. It means that effect of external
factors such as host quality etc. minimizes (Nozad-Bonab and Iranipour 2013).
Development time was 9.6 Æ 0.07 for T. grandis disregarding gender (NozadBonab et al. 2014), 13.5 Æ 0.1 for males and 14.6–15.0 Æ 0.04 for females of
T. vassilievi (Iranipour et al. 2015), 15–16 days for T. djadetshkoe (Abdi 2014),
14.4 Æ 0.17 for O. telenomicida (Rafat et al. 2013) and 13.4 Æ 0.05 for males and
14.2 Æ 0.06 d for females of O. fecundus (Ahmadpour et al. 2013). Small value of
SE in all studies is very interesting. Generation time differs between 10–21 days in
different species at similar temperature regims.
8.5.1.2 Effect on Foraging Behaviour
Searching efficiency, handling time and maximum attack rate are functional
response parameters that may represent the efficiency of a parasitoid, predict density
dependence and also can use for calculating number of parasitoids required for
release. Numerical and aggregation studies also may enhance our knowledge
about the results of release.
8 Superfamily Platygastroidea: Natural Enemies of True Bugs, Moths, Other. . .
315