https://www.crec.ifas.ufl.edu/extension/diaprepes/bibliography/PDF/BioCont381.pdf

Successes and failures in the use of parasitic nematodes for pest control

https://www.crec.ifas.ufl.edu/extension/diaprepes/bibliography/PDF/2BioCont381.pdf

Application technology and environmental considerations for use of entomopathogenic nematodes in biological control

Preface. Acknowledgments. Contributors. Part 1: Perspectives. 1. Critical Issues Related to Nontarget Effects in Classical Biological Control of Insetcs L.E. Ehler. 2. Nontarget Effects of Biological Control: What Are We Trying to Miss? J.A. Lockwood. 3. The Frequency and Strength of Nontarget Effects of Invertebrate Biological Control Agents of Plant Pests and Weeds P. Stiling, D. Simberloff. 4. The Impact of Nontarget Concerns on the Practice of Biological Control R.H. Messing. Part 2: Parasitoids and Predators. 5. Predicting the Risk from Biological Control Agent Introductions: A New Zealand Approach B. Barratt, et al. 6. Parasitoid Drift in Hawaiian Pentatomoids P.A. Follett, et al. 7. Evaluating Nontarget Effects of Classical Biological Control: Fruit Fly Parasitoids in Hawaii as a Case Study J.J. Duan, R.H. Messing. 8. Trichogramma Nontarget Impacts: A Method for Biological Control Risk Assessment D.B. Orr, et al. 9. Coccinellid Introductions: Potential for and Evaluation of Nontarget Effects J.J. Obrycki, et al. 10. Food Webs as a Tool for Studying Nontarget Effects in Biological Control J. Memmott. Part 3: Weeds. 11. Why Things Bite Back: Unintended Consequences of Biological Weed Control P.B. McEvoy, E.M. Coombs. 12. Importation Protocols and Risk Assessment of Weed Biological Control Agents in Australia: The Example of Carmenta nr ithacae T. Withers, et al. 13. Negative Ecological Effects of the Musk Thistle Biological Control Agent, Rhinocyllus conicus S.M. Louda. 14. Biological Control of Musk Thistle: A Reassessment J.R. Nechols. Part 4: Pathogens. 15. Predicting the Host Range of Entomopathogenic Fungi A.E. Hajek, L. Butler. 16. Monitoring the Effects of Bacillus thuringiensis kurstaki on Nontarget Lepidoptera in Woodlands and Forests of Western Oregon J.C. Miller. 17. Environmental Impacts of Entomopathogenic Nematodes Used for Biological Control in Soil M. Barbercheck, L.C. Millar. Index.

Nontarget effects of biological control.

Production and application technology is critical for the success of entomopathogenic nematodes (EPNs) in biological control. Production approaches include in vivo, and in vitro methods (solid or liquid fermentation). For laboratory use and small scale field experiments, in vivo production of EPNs appears to be the appropriate method. In vivo production is also appropriate for niche markets and small growers where a lack of capital, scientific expertise or infrastructure cannot justify large investments into in vitro culture technology. In vitro technology is used when large scale production is needed at reasonable quality and cost. Infective juveniles of entomopathogenic nematodes are usually applied using various spray equipment and standard irrigation systems. Enhanced efficacy in EPN applications can be facilitated through improved delivery mechanisms (e.g., cadaver application) or optimization of spray equipment. Substantial progress has been made in recent years in developing EPN formulations, particularly for above ground applications, e.g., mixing EPNs with surfactants or polymers or with sprayable gels. Bait formulations and insect host cadavers can enhance EPN persistence and reduce the quantity of nematodes required per unit area. This review provides a summary and analysis of factors that affect production and application of EPNs and offers insights for their future in biological insect suppression.

/pdf/entomopathogenic-nematode-production-and-application-1hnp5iaro8.pdf

Entomopathogenic nematode production and application technology

Because of their selectivity and safety, microbial control agents (MCAs) appear to be ready-made components of integrated pest management (IPM) systems that do not pose a threat to applica- tors or the environment and allow other natural enemies to func- tion. Control of several orchard pest insects using MCAs, including viruses, Bacillus thuringiensis, fungi, and entomopathogenic nema- todes (EPNs), have been demonstrated in apple, pear, stone fruits, citrus, and several nut crops. B. thuringiensis is the most used MCA for control of lepidopteran orchard pests. Significant use of EPNs in citrus for control of root weevils is also reported. The granulovirus of codling moth is used increasingly in apple and pear by organic growers, with interest also shown by conventional growers. Although some success has been achieved, in most orchard systems MCAs ac- count for a relatively small proportion of the pest control tactics employed, and in some systems they are not used at all. Research toward improving MCA efficacy and economic competitiveness is required to enhance the role of MCAs in IPM.

Microbial Control of Insect Pests in Temperate Orchard Systems: Potential for Incorporation into IPM ∗

Infectivity is an important measure of virulence in insect pathogens. The proportion of entomopathogenic nematodes that invaded a host, Galleria mellonella (L.), was used as a measure of infectivity in 2 species of entomopathogenic nematodes: S teinernema carpocapsae (Weiser) and Heterorhabditis bacteriophora Poinar. We compared infectivity between nematodes emerging directly from cadavers into sand with nematodes that were applied to sand in aqueous suspensions after collection in a White trap. Assay arenas consisted of 10 G. mellonella larvae in petri dishes filled with moist sand. After 20 or 44 h the larvae were removed and the number of nematodes that had invaded was counted after dissection. Infectivity of H. bacteriophora was significantly greater when nematodes emerged directly into sand compared with the aqueous application. After 24 h, a11% of H. bacteriophora from cadaver treatments had penetrated into a host, whereas infectivity of aqueous treatments was 4–10 times lower. A similar trend was observed after 48 h. The infectivity of S. carpocapsae from cadaver treatments was a24% in both treatments. An additional experiment was conducted for H. bacteriophora, which consisted of 3 treatments: nematodes directly from cadavers, nematodes applied in aqueous suspension, and nematodes in aqueous suspension that were exposed to an extract from macerated host cadavers. Higher infectivity was observed in the amended aqueous suspension compared with aqueous nematodes without the extract. This study emphasizes that differences in fitness and behavior must exist between nematodes reared under standard laboratory procedures and those in nature.

Comparison of entomopathogenic nematode infectivity from infected hosts versus aqueous suspension

Dispersal of the entomopathogenic nematodes Heterorhabdidtis bacteriophora Poinar (HP88 strain) and Steinernema carpocapsae (Weiser) (All strain) was measured when nematodes were applied to sand either in Galleria mellonella (L.) cadavers or in aqueous suspension. Dispersal ability was estimated as the percentage of nematodes that migrated through sand or from sand onto an agar surface. Results of overnight assays indicated that the dispersal ability of both species was significantly greater when nematodes were applied in cadavers relative to when they were applied in aqueous suspension. Assays that measured migration onto an agar surface after 1 h also indicated enhanced dispersal of S. carpocapsae when exiting cadavers, but results from H. bacteriophora only weakly supported the trend. The relatively greater movement of nematodes exiting infected hosts was not the result of differences in nematode age or persistence in sand. The enhanced dispersal may have been caused by physiological or behavioral differences between nematodes exiting hosts and those kept in aqueous suspension. Because of the dispersal advantage, application of entomopathogenic nematodes in infected hosts may increase their efficacy in biological control. This study demonstrated a need to further investigate behavior of entomopathogenic nematodes when they exit a host under natural conditions.

Comparison of Entomopathogenic Nematode Dispersal from Infected Hosts Versus Aqueous Suspension

The Diaprepes root weevil, Diaprepes abbreviatus (L) is the most severe weevil pest in Florida citrus Entomopathogenic nematodes have effectively suppressed larval populations of D abbreviatus Our objective was to conduct a broad laboratory comparison of entomopathogenic nematodes for virulence toward larvae of D abbreviatus The study was conducted at three temperatures (20, 24, and 29°C) and included nine entomopathogenic species and 17 strains: Heterorhabditis bacteriophora Poinar (Baine, NJ1, Hb, Hbl, HP88, and Lewiston strains), H indica Poinar, Karunakar & David (original and Hom1 strains), H marelatus Liu & Berry (IN and Point Reyes strains), H megidis Poinar, Jackson & Klein (UK211 strain), H zealandica Poinar (NZH3 strain), Steinernema riobrave Cabanillas, Poinar & Raulston (355 strain), S carpocapsae (Weiser) (All strain), S feltiae (Filipjev) (SN and UK76 strains), and S glaseri (Steiner) (NJ43 strain) At 20°C, the greatest mortality was caused by S riobrave although it was not significantly greater than H bacteriophora (Baine), H bacteriophora (Hb), H bacteriophora (Hbl), and H indica (original) At 24 and 29°C, S riobrave caused greater larval mortality than other nematodes tested Two strains of H indica, H bacteriophora (Baine), and S glaseri were next in terms of virulence at 29°C Our results suggest that S riobrave has the greatest potential for control of D abbreviatus

Virulence of Entomopathogenic Nematodes to Diaprepes abbreviatus (Coleoptera: Curculionidae) in the Laboratory

http://www.tsusinvasives.org/dotAsset/bcf86193-8f9f-412a-9aaa-cdc24b1de36f.pdf

David I. Shapiro

Papers

Comparison of entomopathogenic nematode infectivity from infected hosts versus aqueous suspension

Comparison of Entomopathogenic Nematode Dispersal from Infected Hosts Versus Aqueous Suspension

Virulence of Entomopathogenic Nematodes to Diaprepes abbreviatus (Coleoptera: Curculionidae) in the Laboratory

Entomopathogenic Nematodes and Other Natural Enemies as Mortality Factors for Larvae of Diaprepes abbreviatus (Coleoptera: Curculionidae)

Trait Stability and Fitness of the Heat Tolerant Entomopathogenic NematodeHeterorhabditis bacteriophoraIS5 Strain