“…White grubs, however, have coevolved with soil pathogens such as entomopathogenic nematodes and developed a series of behavioral [i.e., aggressive and evasive behaviors (Schroeder et al, 1993;Gaugler et al, 1994;Koppenhöfer et al, 2000)], morphological [i.e., sieve plate-covered spiracles (Forschler and Gardner, 1991;Koppenhöfer et al, 2007 and discussion therein) and thick peritrophic membrane (Forschler and Gardner, 1991;Cui et al, 1993;Thurston et al, 1994)], and physiological [i.e., inactivating gut juices (Wang et al, 1995) and strong immune response (e.g., Wang et al, 1994Wang et al, , 1995] barriers to infection. The high variability in white grub susceptibility and/or nematode virulence in different white grub-nematode species combinations suggest different degrees of expression of the above described defense mechanisms among white grubs species and/or different levels of ability among nematode species to circumvent these defenses.…”