Combined effects of the entomopathogenic fungus, Paecilomyces fumosoroseus Apopka-97, and the generalist predator, Dicyphus hesperus, on whitefly populations

Abstract

The effects of intraguild interactions between Dicyphus hesperus Knight (Hemiptera: Miridae) and Paecilomyces fumosoroseus Apopka-97 (PFR-97 TM ) (Wize) Brown and Smith (Ascomycota: Hypocreales) on Trialeurodes vaporariorum (Westwood) (Hemiptera: Aleyrodidae) populations were investigated in tomato greenhouse microcosms. Conditions were established in which interference or synergy would most likely occur; namely, a high number of available whiteflies were combined with large numbers of both D. hesperus and PFR-97 TM . We measured live whitefly density in a factorial repeated measures experiment where plants were provided or withheld releases of D. hesperus and/or applications of PFR-97 TM for 6 weeks. Releases of D. hesperus were made at a rate of 10 adults/plant during the first and third week and PFR-97 TM suspensions were applied with a backpack sprayer at a rate of 18 Â 10 7 , 1.3 Â 10 7 and 1.2 Â 10 7 viable blastospores/ml during the first, third and fourth week, respectively. Results revealed a non-significant interaction effect between D. hesperus and PFR-97 TM , indicating that their actions were independent. Individual whitefly reductions of 48% and 35% were achieved by PFR-97 TM and D. hesperus, respectively. Collectively, the natural enemies reduced whitefly densities by 62% relative to the controls. The density of D. hesperus adults was unaffected by multiple applications of PFR-97 TM . These results suggest that the combination of generalist entomopathogenic fungi and generalist predators has the potential to cause increased pest mortality despite evidence of minimal interference.

Susceptibility of Myzus persicae, Brevicoryne brassicae and Nasonovia ribisnigri to Fungal Biopesticides in Laboratory and Field Experiments

“…Cordyceps fumosorosea s.l. also has a relatively large host range as a species, making it attractive for development as a biopesticide product [35], particularly against pests of greenhouse crops [36][37][38].…”

Compatibility of the Predatory Beetle, Delphastus catalinae, with an Entomopathogenic Fungus, Cordyceps fumosorosea, for Biocontrol of Invasive Pepper Whitefly, Aleurothrixus trachoides, in Florida

“…Therefore, based on the results of this study we can suggest in an IPM scenario that when both D. catalinae and Cfr are used together, it is best to spray the fungus first, and allow it to dry prior to releasing the predator. However, in a greenhouse study, Alma et al [ 9 ] observed that the combination of a mirid predator after being sprayed with Cfr while feeding on greenhouse whitefly nymphs found on tomato plants, that the efficacy of the predator was not negatively affected compared to the control. In corroboration with our laboratory study, Poprawski et al [ 40 ] observed that the adult ladybird beetles ( Serangium parcesetosum Sicard) sprayed with Cfr consumed whitefly nymphs ( Bemisia sp.)…”

“…Past studies have shown that fungal entomopathogens are critical regulatory factors in managing arthropod pest populations [ 5 , 6 , 7 ]. These biological control agents are also safe for non-target organisms and are compatible with other natural enemies such as predators and parasitoids [ 8 , 9 , 10 ]. Among these fungal entomopathogens, Cordyceps (= Isaria ) fumosorosea (Wize) Kepler, B. Shrestha & Spatafora (Hypocreales: Cordycipitaceae) is regularly used in greenhouse and nursery production systems where it has proven to be efficacious against various insect pests and can tolerate climatic conditions in the southern United States [ 11 ].…”

Effect of photoperiod and host distribution on the horizontal transmission ofIsaria fumosorosea(Hypocreales: Cordycipitaceae) in greenhouse whitefly assessed using a novel model bioassay

“…Entomopathogenic fungi are being developed as major components of integrated pest management programs for controlling T. vaporariorum and other whiteflies (Fransen 1993;Poprawski & Jones 2000;Meekes et al 2002;Vidal et al 2003;Cuthbertson & Walters 2005;Cuthbertson et al 2008). Most research using fungi for controlling aleyrodids has focused primarily on using Beauveria bassiana (Balsamo) Vuillemin, Lecanicillium muscarium (Petch) Zare & Gams and Aschersonia species; however, Isaria fumosorosea (=Paecilomyces fumosoroseus) Wize (Hypocreales: Cordycipitaceae), has also been shown to cause epizootics in whitefly populations on various host plants (Lacey et al 1995;Wraight et al 2000;Meekes et al 2000;Gökçe & Er 2005;Saito 2005;Alma et al 2007). To determine the efficacy of an entomopathogen used in any control program, both biotic (host density, developmental stage, etc.)…”