endosymbionts were identified from these insects and it was shown that symbiotic
bacteria play important roles in the biology of the insects as symbiont removal
resulted in impaired growth, development and reproduction. It was shown that high
temperature and chemical surface sterilization resulted in symbiont suppression and
an overall reduction in insect fitness. Therefore, methods targeting endosymbionts in
these insects such as increased temperature and chemical surface sterilization could
potentially be used to control pistachio stink bugs (Kashkouli et al. 2019c). Genomic
studies of the stinkbug A. arabicum’s bacterial symbionts resulted in a draft
genomeof the symbiont, which is intermediate in size between free-living Pantoea
and other highly-reduced obligate symbionts of stink bugs. The genomic annotation
revealed that the symbiont retains the predicted capability to perform biosynthesis of
amino-acids, vitamins and other metabolites. In addition, approximately one third of
total ORFs were classified as pseudogenes. On the basis of this study and the
geographic origin of the bacteria, (persica ¼ Persia, Iran), we propose the name
“Candidatus Pantoea persica” for the midgut symbiont associated with the stinkbug
A. arabicum (Kashkouli et al. 2019b).
Ayoubi et al. (2020), characterized the bacterial endosymbionts of Aphis gossypii
(Glover 1877) (Hem.: Aphididae) in Karaj populations of the aphid. In this study,
Buchnera aphidicola, Hamiltonella defense and Arsenophonus sp. were detected.
Reduction in Buchnera caused prolonged development and no progeny production.
Furthermore, secondary symbiont reduction led to a reduction of the total life span,
intrinsic rate of natural increase, and emergence of abnormal offspring in treated
insects.
13.3 Microsporidia
Currently, 93 of the 200 described genera of microsporidia have an insect host. The
microsporidian infections (microsporidioses) are classified into two groups, chronic
and acute. In infection with microsporidia, there are various signs and symptoms
such as tissue manifestations, abnormal development, and behavioral changes. The
external effects in infected larvae are changes in color, size, form, or behavior when
compared to healthy individuals. The fat body and midgut epithelium are two main
tissues in which microsporidia affect them usually (Becnel and Andreadis 2014).
Most microsporidian insect pathogens induce sublethal effects on the hosts resulting
in reduced fertility, shortened longevity, and loss of vigor (Brooks 1988; Solter et al.
2012). Vertical transmission is a major pathway of transmission for many
microsporidian insect pathogens. Contamination of the environment with spores is
typically achieved when an infected host dies or when spores are released in fecal
excrement that leads to horizontal transmission (Becnel and Andreadis 2014).
13 Insect Pathogenic Viruses, Microsporidians and Endosymbionts
525
bacteria play important roles in the biology of the insects as symbiont removal
resulted in impaired growth, development and reproduction. It was shown that high
temperature and chemical surface sterilization resulted in symbiont suppression and
an overall reduction in insect fitness. Therefore, methods targeting endosymbionts in
these insects such as increased temperature and chemical surface sterilization could
potentially be used to control pistachio stink bugs (Kashkouli et al. 2019c). Genomic
studies of the stinkbug A. arabicum’s bacterial symbionts resulted in a draft
genomeof the symbiont, which is intermediate in size between free-living Pantoea
and other highly-reduced obligate symbionts of stink bugs. The genomic annotation
revealed that the symbiont retains the predicted capability to perform biosynthesis of
amino-acids, vitamins and other metabolites. In addition, approximately one third of
total ORFs were classified as pseudogenes. On the basis of this study and the
geographic origin of the bacteria, (persica ¼ Persia, Iran), we propose the name
“Candidatus Pantoea persica” for the midgut symbiont associated with the stinkbug
A. arabicum (Kashkouli et al. 2019b).
Ayoubi et al. (2020), characterized the bacterial endosymbionts of Aphis gossypii
(Glover 1877) (Hem.: Aphididae) in Karaj populations of the aphid. In this study,
Buchnera aphidicola, Hamiltonella defense and Arsenophonus sp. were detected.
Reduction in Buchnera caused prolonged development and no progeny production.
Furthermore, secondary symbiont reduction led to a reduction of the total life span,
intrinsic rate of natural increase, and emergence of abnormal offspring in treated
insects.
13.3 Microsporidia
Currently, 93 of the 200 described genera of microsporidia have an insect host. The
microsporidian infections (microsporidioses) are classified into two groups, chronic
and acute. In infection with microsporidia, there are various signs and symptoms
such as tissue manifestations, abnormal development, and behavioral changes. The
external effects in infected larvae are changes in color, size, form, or behavior when
compared to healthy individuals. The fat body and midgut epithelium are two main
tissues in which microsporidia affect them usually (Becnel and Andreadis 2014).
Most microsporidian insect pathogens induce sublethal effects on the hosts resulting
in reduced fertility, shortened longevity, and loss of vigor (Brooks 1988; Solter et al.
2012). Vertical transmission is a major pathway of transmission for many
microsporidian insect pathogens. Contamination of the environment with spores is
typically achieved when an infected host dies or when spores are released in fecal
excrement that leads to horizontal transmission (Becnel and Andreadis 2014).
13 Insect Pathogenic Viruses, Microsporidians and Endosymbionts
525