Trombidioidea. Saboori and Hakimitabar (2013) provided a checklist for Iranian
Trombidioidea and mentioned to five families, 22 genera and 32 species. Some
cosmopolite genera such as Trombidium and Parathrombium attack wide range of
arthropods but, undoubtedly, the genus Allothrombium is potentially the most
economic biocontrol agent in the family (Zhang 1991). One of the species, A.
pulvinum Ewing, parasitizes aphids in the larval stage and prey spider mites in
postlarval stages (Zhang 1992).
In Iran, there are some non-taxonomical studies on two representatives of the
Allothrombium namely A. shirazicum Zhang and A. pulvinum. Biology of
Allothrombium shirazicum as a potential biocontrol agent of Aphis punicae Passerini
and some other arthropods has been studied in central parts of Iran (Saboori and
Kamali 1999). The mite raises one generation per year. The eggs hatch in spring and
larvae usually do not show superparasitism. Nymphs emerge in summer and adults
appear in autumn when they prey on microarthropods and their eggs. Adults and
eggs can hibernate, and at late winter overwintered females produce eggs, mostly
hatched in spring. Regarding A. pulvinum, in Mazandaran province (northern Iran),
larvae emerge in mid-spring and reach to the most abundant population in late spring
(Saboori and Zhang 1996). Saboori et al. (2007) stated that larvae of A. shirazicum
constitute about 69% of natural enemies of pomegranate aphid in mid-spring with
maximum 13% parasitism in presence of coccinellids, syrphids, hymenopterans and
spiders.
A. pulvinum larvae prefers Hyalopterus amygdali (Blanchard) in presence of two
other aphids, Aphis gossypii Glover and Macrosiphum rosae (L.), showing that the
parasitic larvae mostly prefer host aphids with less defence ability, less activity,
more mildew productivity, thinner cuticle and more attractive body odor (Hosseini
et al. 2002). In northern Iran, A. pulvinum adults can prey on two pests of citrus trees,
Planococcus citri (Risso) and Pulvinaria aurantii Cockerell, with a preference on P.
citri (Saboori et al. 2003a, b). Results of experimental studies revealed that each A.
pulvinum adult can feed on 4.2, 2.8, 1.3, 0.8 and 0.8 of H. amygdali, Aphis gossypii,
Macrosiphum rosae, A. fabae Scopoli and T. urticae per day, respectively (Hosseini
et al. 2004). Experimental surveys conducted by Hosseini et al. (2005) showed that
A. pulvinum deutonymph can consume 6.5 and 2.2 eggs of T. urticae and
Amphitetranychus vienensis per day, respectively. In addition, 2.8 and 1.2 adult
females of the mentioned tetranychids could be feed per day, respectively. The
results of host preference studies proved T. urticae is preferred prey of A. pulvinum
deutonymphs. In current study, authors demonstrated type III functional response of
A. pulvinum deutonymphs on different densities of adult female individuals of T.
urticae and density-dependent in low densities.
The following table (Table 3.4) listed some selective larval species of the Iranian
trombidiids attacking insect pests. Conservation measures are also recommended as
erythraeids.
3 Biological Control of Pests by Mites in Iran
115
Trombidioidea and mentioned to five families, 22 genera and 32 species. Some
cosmopolite genera such as Trombidium and Parathrombium attack wide range of
arthropods but, undoubtedly, the genus Allothrombium is potentially the most
economic biocontrol agent in the family (Zhang 1991). One of the species, A.
pulvinum Ewing, parasitizes aphids in the larval stage and prey spider mites in
postlarval stages (Zhang 1992).
In Iran, there are some non-taxonomical studies on two representatives of the
Allothrombium namely A. shirazicum Zhang and A. pulvinum. Biology of
Allothrombium shirazicum as a potential biocontrol agent of Aphis punicae Passerini
and some other arthropods has been studied in central parts of Iran (Saboori and
Kamali 1999). The mite raises one generation per year. The eggs hatch in spring and
larvae usually do not show superparasitism. Nymphs emerge in summer and adults
appear in autumn when they prey on microarthropods and their eggs. Adults and
eggs can hibernate, and at late winter overwintered females produce eggs, mostly
hatched in spring. Regarding A. pulvinum, in Mazandaran province (northern Iran),
larvae emerge in mid-spring and reach to the most abundant population in late spring
(Saboori and Zhang 1996). Saboori et al. (2007) stated that larvae of A. shirazicum
constitute about 69% of natural enemies of pomegranate aphid in mid-spring with
maximum 13% parasitism in presence of coccinellids, syrphids, hymenopterans and
spiders.
A. pulvinum larvae prefers Hyalopterus amygdali (Blanchard) in presence of two
other aphids, Aphis gossypii Glover and Macrosiphum rosae (L.), showing that the
parasitic larvae mostly prefer host aphids with less defence ability, less activity,
more mildew productivity, thinner cuticle and more attractive body odor (Hosseini
et al. 2002). In northern Iran, A. pulvinum adults can prey on two pests of citrus trees,
Planococcus citri (Risso) and Pulvinaria aurantii Cockerell, with a preference on P.
citri (Saboori et al. 2003a, b). Results of experimental studies revealed that each A.
pulvinum adult can feed on 4.2, 2.8, 1.3, 0.8 and 0.8 of H. amygdali, Aphis gossypii,
Macrosiphum rosae, A. fabae Scopoli and T. urticae per day, respectively (Hosseini
et al. 2004). Experimental surveys conducted by Hosseini et al. (2005) showed that
A. pulvinum deutonymph can consume 6.5 and 2.2 eggs of T. urticae and
Amphitetranychus vienensis per day, respectively. In addition, 2.8 and 1.2 adult
females of the mentioned tetranychids could be feed per day, respectively. The
results of host preference studies proved T. urticae is preferred prey of A. pulvinum
deutonymphs. In current study, authors demonstrated type III functional response of
A. pulvinum deutonymphs on different densities of adult female individuals of T.
urticae and density-dependent in low densities.
The following table (Table 3.4) listed some selective larval species of the Iranian
trombidiids attacking insect pests. Conservation measures are also recommended as
erythraeids.
3 Biological Control of Pests by Mites in Iran
115