Storage temperature can influence beneficial nematode activity
Several different species of white grubs including Anomala orientalis, Ataenius spretulus, Blitopertha orientalis, Cotinus nitida, Cyclocephala borealis, Cyclocephala pasadenae, Cyclocephala hirta, Exomala orientalis, Hoplia philanthus, Maladera castanea, Melolontha melolontha, Phyllophaga Spp. and Rhizotrogus majalis are major pests of turf grass.
The larvae (Fig. 1. ) of all these white grub species cause a serious damage by feeding on the roots of different types of turf grasses that are planted in your yards, recreational parks and golf courses and whit grub adults are voracious feeders of foliage and flowers (Fig. 2) of many plant species planted in different landscapes.
Although several different species of beneficial entomopathogenic nematodes includingHeterorhabditis bacteriophora, Heterorhabditis zealandica and Steinernema glaseri have showed a potential to manage white grubs, Steinernema scarabaei considered as the most effective in reducing the population of most of the above stated species of white grubs.
However, it has been reported that the storage temperature and time influences the dispersal and infectivity of Steinernema scarabaei infective juveniles when applied against white grubs. According to Koppenhofer et al (2013), dispersal rate of infective juveniles of Steinernema scarabaei was declined faster during storage at 8oC than at room temperature, but the virulence and infectivity remained high only in the infective juveniles that were stored at 8oC storage temperature.
Read following papers for more information on interaction between beneficial nematodes and various species of white grubs.
An, R. and Grewal, P.S. 2007. Differences in the virulence of Heterorhabditis bacteriophora and Steinernema scarabaei to three white grub species: The relative contribution of the nematodes and their symbiotic bacteria. Biological Control 43: 310-316.
Ansari, M.A., Ali, F. and Moens, M. 2006. Compared virulence of the Belgian isolate of Steinernema glaseri (Rhabditida: Steinernematidae) and the type population of S-scarabaei to white grub species (Coleoptera: Scarabaeidae). Nematology 8: 787-791.
Koppenhofer, A.M. and Fuzy, E.M. 2003. Steinernema scarabaei for the control of white grubs. Biological Control 28: 47-59.
Koppenhofer, A.M. and Fuzy, E.M. 2006. Effect of soil type on infectivity and persistence of the entomopathogenic nematodes Steinernema scarabaei, Steinernema glaseri, Heterorhabditis zealandica, and Heterorhabditis bacteriophora. Journal of Invertebrate Pathology. 92: 11-22.
Koppenhofer, A.M. and Fuzy, E.M. 2009. Long-term effects and persistence of Steinernema scarabaei applied for suppression of Anomala orientalis (Coleoptera: Scarabaeidae). Biological Control 48: 63-72.
Koppenhofer, A.M., Ebssa, L. and Fuzy, E.M. 2013. Storage temperature and duration affect Steinernema scarabaei dispersal and attraction, virulence, and infectivity to a white grub host. Journal of Invertebrate Pathology 112: 129-137.
Koppenhofer, A.M., Fuzy, E.M., Crocker, R.L., Gelernter, W.D. and Polavarapu, S. 2004. Pathogenicity of Heterorhabditis bacteriophora, Steinernema glaseri, and S. scarabaei (Rhabditida: Heterorhabditidae, Steinernematidae) against 12 white grub species (Coleoptera: Scarabaeidae). Biocontrol Science and Technology. 14: 87-92.
Koppenhofer, A.M., Grewal, P.S. and Fuzy, E.M. 2006. Virulence of the entomopathogenic nematodes Heterorhabditis bacteriophora, Heterorhabditis zealandica, and Steinernema scarabaei against five white grub species (Coleoptera: Scarabaeidae) of economic importance in turfgrass in North America. Biological Control 38: 397-404.