Biological control in termite management: The potential of nematodes and fungal pathogens
  Key Words  
  Heterorhabditis, Metarhizium anisopliae, Beauveria bassiana, subterranean termites
  M. Lenz
  A brief overview on the options for biological control of termites is presented. Many organisms have been identified as being able to kill termites. However, we do not know their real impact on field populations of termites. Research has focused on some entomopathogenic nematodes and the fungi Beauveria bassiana and Metarhizium anisopliae. Only a limited number of field studies have been conducted using both groups of organisms as control agents for termites. Work with M. anisopliae, notably from Australia, is discussed in more detail in this paper. Strains selected for field trials have to: be virulent; be able to tolerate temperatures above 30 C; pose no health threats to humans and higher animals; be easily mass produced; and have long-lived spores that are robust enough for easy formulation and storage. Spores from virulent isolates of M. anisopliae are repellent to termites and behavioural defence mechanisms by termites can limit the effectiveness of conidia applications. A number of options are available to formulate the spore product thus rendering it less repellent. Applications of conidia as inundative treatments to termite sites, or within an attractive bait matrix, are options for termite control with M. anisopliae. Microbial pathogens will solve certain termite problems but may not help with others. However, they have their place as one of the tools in integrated termite (pest) management.