Influence of Bacterial Secondary Symbionts in <i>Sitobion avenae</i> on Its Survival Fitness against Entomopathogenic Fungi, <i>Beauveria bassiana</i> and <i>Metarhizium brunneum</i>
Sajjad Ali,
Asif Sajjad,
Qaiser Shakeel,
M. Aslam Farooqi,
M. Anjum Aqueel,
Kaleem Tariq,
Muhammad Irfan Ullah,
Aamir Iqbal,
Aftab Jamal,
Muhammad Farhan Saeed,
Barbara Manachini
Affiliations
Sajjad Ali
Department of Entomology, The Islamia University of Bahawalpur, Bahawalpur 63100, Pakistan
Asif Sajjad
Department of Entomology, The Islamia University of Bahawalpur, Bahawalpur 63100, Pakistan
Qaiser Shakeel
Department of Plant Pathology, The Islamia University of Bahawalpur, Bahawalpur 63100, Pakistan
M. Aslam Farooqi
Department of Entomology, The Islamia University of Bahawalpur, Bahawalpur 63100, Pakistan
M. Anjum Aqueel
Department of Entomology, The Islamia University of Bahawalpur, Bahawalpur 63100, Pakistan
Kaleem Tariq
Department of Agriculture Entomology, Abdul Wali Khan University, Mardan 23200, Pakistan
Muhammad Irfan Ullah
Department of Entomology, University of Sargodha, Sargodha 40100, Pakistan
Aamir Iqbal
Department of Crop Sciences, Georg-August University, 37073 Goettingen, Germany
Aftab Jamal
Department of Soil and Environmental Sciences, Faculty of Crop Production Sciences, The University of Agriculture, Peshawar 25130, Pakistan
Muhammad Farhan Saeed
Department of Environmental Sciences, COMSATS University Islamabad, Vehari Campus, Vehari 61100, Pakistan
Barbara Manachini
Department of Agricultural, Food and Forest Sciences (SAAF), University of Palermo, Viale delle Scienze 13, 90128 Palermo, Italy
The research was focused on the ability of wheat aphids Sitobion avenae, harboring bacterial secondary symbionts (BSS) Hamiltonella defensa or Regiella insecticola, to withstand exposure to fungal isolates of Beauveria bassiana and Metarhizium brunneum. In comparison to aphids lacking bacterial secondary symbionts, BSS considerably increased the lifespan of wheat aphids exposed to B. bassiana strains (Bb1022, EABb04/01-Tip) and M. brunneum strains (ART 2825 and BIPESCO 5) and also reduced the aphids’ mortality. The wheat aphid clones lacking bacterial secondary symbionts were shown to be particularly vulnerable to M. brunneum strain BIPESCO 5. As opposed to wheat aphids carrying bacterial symbionts, fungal pathogens infected the wheat aphids lacking H. defensa and R. insecticola more quickly. When treated with fungal pathogens, bacterial endosymbionts had a favorable effect on the fecundity of their host aphids compared to the aphids lacking these symbionts, but there was no change in fungal sporulation on the deceased aphids. By defending their insect hosts against natural enemies, BSS increase the population of their host society and may have a significant impact on the development of their hosts.
