Here, we show that these relatively common landscape structures accompanying coal combustion indeed host insects of extraordinary conservation value.
Once inside they can exploit the colony without the host insects noticing, or even stage a hostile takeover.
Fifty-seven species were considered as recognizable potential host insects of O. sinensis, whilst eight as indeterminate hosts and 26 as non-hosts (Wang and Yao, 2011).
Further, the correlation of genetic distances between O. sinensis and its host insects indicated that they coevolved through the history (Quan et al., 2014).
This is, for example, because the foraging behaviour of EPNs is less important for the attack of host insects in small arenas of bioassays, than under field conditions.
The nematode-baiting method with alternative host insects as baits was employed as per Bedding and Akhurst (1975) and Yan et al. (2016) to assess whether the applied EPNs had established and persisted in the field soil.
This indicates that the applied EPNs were of good quality as they need energy to survive some time in the soil until finding and propagating in the host insects.
A technique for disinfecting the insect cuticle with a fungicide and verifying the presence of EPF in infected host insects after feeding on a substrate containing these fungi was described and applied.
A few studies investigated the infection of EPNs on PO activity of host insects (Brivio et al. 2002; Walter et al. 2008; Ebrahimi et al. 2014a, 2014b; Kramarz et al. 2016).
It is well-known that EPN species/strains could vary tremendously in their virulence (expressed in terms of pathogenicity) against different host insects (Laznik et al., 2010), and their efficiency is highly affected by different factors including concentration, host density, and temperature (Trdan et al., 2009).
Advantages of EPNs as one biocontrol agents include the wide range of their host insects, ability to seek a host actively, fast insect killing, fast breeding, and no hazard for the environment or higher animals, as well as a possibility of their formulation, storing, and simple application (Jaworska and Gorczyca, 2002).
