Virulence and survival of native entomopathogenic nematodes for the management of white grubs in South Africa

Abate, Birhan Addisie; Slippers, Bernard; Wingfield, Michael J.; Conlong, Des E.; Burger, Divan Aristo; Hurley, Brett Phillip

doi:10.1016/j.biocontrol.2019.104043

Cited by 14 publications

(6 citation statements)

References 44 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Blatt et al (2021) showed that S. feltiae and H. bacteriophora survived and remained infective in soil without irrigation for nine weeks. We found that the survival rate of Steinernema was higher than that of Heterorhabditis, and this corroborates previous studies (Abate et al 2019). The higher survival rate of Steinernema might be the result of higher lipid reserves in this species when compared to Heterorhabditis (Selvan et al 1993).…”

Section: Discussionsupporting

confidence: 93%

“…EPN isolates may be adapted to the environmental conditions at their original location of isolation, and, in those environments, may be more virulent compared to introduced or commercial isolates (Abate et al 2019). As the efficacy of EPNs can depend on several abiotic and biotic factors (including EPN species and target pest species), proper bioassays are important, in particular ones that consider the specific life cycle aspects of the target pest in the soil.…”

Section: Discussionmentioning

confidence: 99%

See 1 more Smart Citation

Effect of temperature on survival of Australian entomopathogenic nematodes and their virulence against the Queensland fruit fly, Bactrocera tryoni

et al. 2022

View full text Add to dashboard Cite

Entomopathogenic nematodes (EPNs) are commonly used biocontrol agents of insect pests, with a wide range of commercially available isolates targeting specific pests. New isolates are, however, required to improve pest control across a wider range of environmental conditions for target pests, including emerging threats. We assessed the effect of temperature on survival and virulence of 17 Australian isolates of five EPN species (Heterorhabditis bacteriophora, Heterorhabditis indica, Heterorhabditis marelatus, Heterorhabditis zealandica and Steinernema feltiae) against larvae and pupae of the Queensland fruit fly, Bactrocera tryoni. All isolates still infected and killed larvae after infective juveniles (IJ) had been kept without insect hosts at 15 °C, 25 °C or 30 °C for two weeks, indicating their potential to remain viable under field conditions. However, the mean LD50 value ranged from 35 to 150 and was generally lower at 15 °C than at 25 °C and 30 °C. Similarly, after IJs had been kept at 25 °C for 1–3 weeks without insect hosts, all isolates infected B. tryoni larvae, with mean LD50 values ranging from 25 to 144. Interestingly, 15 isolates infected and killed B. tryoni pupae after one week, with a mean LD50 value between 130 and 209, but only two isolates after two weeks, with a mean LD50 value between 229 to 209. No pupal mortality was seen after three weeks. In absence of hosts, EPNs survived longer at 15 °C and 25 °C than at 30 °C. Complete EPN mortality occurred after nine weeks at 30 °C, and after 18 weeks at 15 °C and 25 °C, except for some survival in one S. feltiae isolate (Sf.ECCS). Overall, six isolates of H. indica (Hi.HRN2, Hi.LMI2, Hi.QF6), H. bacteriophora (Hb.HIE), H. zealandica (Hz.NAR1) and S. feltiae (Sf.ECCS) performed best and need further testing as potential biocontrol agents against B. tryoni under semi-field and field conditions.

show abstract

Section: Discussionsupporting

confidence: 93%

Section: Discussionmentioning

confidence: 99%

Effect of temperature on survival of Australian entomopathogenic nematodes and their virulence against the Queensland fruit fly, Bactrocera tryoni

et al. 2022

View full text Add to dashboard Cite

show abstract

“…The varying degrees of susceptibility of white grubs for the different EPN species or isolates in the current study aligns well with what has already been shown for white grub susceptibility to EPNs elsewhere (Grewal et al 2005;An et al 2012;Abate et al 2019). Consensus exists that the efficacy of EPNs against white grubs can be difficult to predict, due to the control efficacy recorded from previous experiments being inconsistent (Grewal et al 2005).…”

Section: Discussionsupporting

confidence: 87%

“…Despite the diversity of native EPNs in South Africa and their potential as biological control agents for white grubs, so far only one study has been undertaken to evaluate the potential use of EPNs to control white grubs in South Africa. Abate et al (2019) evaluated the efficacy of both native and non-native EPNs to control the white grub, Heteronychus licas Klug in sugarcane plantations. There is need to evaluate the use of EPNs on more white grub pests in sugarcane and plantation forests in South Africa.…”

Section: Introductionmentioning

confidence: 99%

Susceptibility of white grubs from forestry and sugarcane plantations in South Africa to entomopathogenic nematodes

et al. 2023

Self Cite

View full text Add to dashboard Cite

The control of white grub (Coleoptera: Scarabaeidae) pests of sugarcane and forest plantations is difficult due to their cryptic nature and resistance to chemicals. This study evaluated the potential use of entomopathogenic nematodes (EPNs) as an alternative control method. Laboratory bioassays were performed with 12 locally isolated EPN species to determine the susceptibility of third instar larvae of the white grubs Schizonycha affinis Boheman, Pegylis sommeri Burmeister, Monochelus sp. and Maladera sp. 4. Concentration trials to determine lethal dosages for three of the white grub species were performed using Heterorhabditis zealandica Poinar MJ2C. Bioassays were performed to determine whether nematodes could develop inside the cadavers of S. affinis and P. sommeri as these had shown the lowest susceptibility to EPNs. The mortality percentage of the white grubs, although varying significantly, was found to be low for most of the EPN species, except H. zealandica. The highest percentage mortality of white grubs was observed at four weeks post inoculation with the rate of mortality being highest in the first week. Schizonycha affinis had the lowest LD50 of 38 Infective juveniles (IJs) per larva after 28 days, compared to Maladera sp. 4, with 284 IJs per larva, and P. sommeri, with 1035 IJs per larva. The dissection of insect cadavers revealed possible limiting factors for low susceptibility, due to the nematodes and their associated symbiotic bacteria’s inability to infect the insect haemocoel, with no EPNs being found inside some of the cadavers.

show abstract

“…Some attempts of pest control were carried out by incorporating non-native EPNs in major crops worldwide [44,45]. However, these strains failed to parasitize local entomofauna, probably due to environmental conditions or the presence of pollutants in soils [44].…”

Section: Introductionmentioning

confidence: 99%

Molecular Identification and Phylogenetic Diversity of Native Entomopathogenic Nematodes, and Their Bacterial Endosymbionts, Isolated from Banana and Plantain Crops in Western Colombia

Londoño-Caicedo,

Uribe-Londoño,

Buitrago-Bitar

et al. 2023

Agronomy

View full text Add to dashboard Cite

With the increasing negative impacts of food production worldwide caused by pests, the recovery of native entomopathogenic nematodes (EPNs) is relevant, since they are adapted to local environments, entomofauna, and significant virulence. Therefore, the present study was designed to recover and understand the phylogenetic diversity of EPNs and their associated bacterial endosymbionts, from banana and plantain crops, as alternatives for the control of weevil species. An extensive sampling of western Colombia covered 325 ha, yielding the recovery of three EPNs’ isolates (0.49% of the samples). The molecular characterization included four mitochondrial and nuclear loci, which, after merging with the sequences of 48 species, confirmed the presence of Steinernema carpocapsae, the first report of S. costaricense in South America, and monophyly in most of the Steinernema clades. The tree topologies were consistent for the nuclear loci but not for mitochondrial, probably due to the high nucleotide substitution rate, deficit in the number of species available for these loci, and incomplete lineage sorting. The endosymbiotic bacteria associated with S. carpocapsae were identified as Xenorhabdus nematophila. However, the S. costaricense bacterial symbiont presented a genetic similarity to X. koppenhoeferi and X. khoisanae, which are still uncertain in their classification. The identification of S. costaricense in South America indicates the wide range distribution of this species in the Americas and its ability to persist in different soil types. For the first time, EPN isolation and phylogenetic characterization are directed to plantain and banana crops. Leveraging EPNs’ diversity promises novel applications for crop protection, while the genetic resources from the bacterial endosymbionts may provide metabolites with a wide spectrum of uses, either for agricultural or medicinal purposes.

show abstract

Virulence and survival of native entomopathogenic nematodes for the management of white grubs in South Africa

Cited by 14 publications

References 44 publications

Effect of temperature on survival of Australian entomopathogenic nematodes and their virulence against the Queensland fruit fly, Bactrocera tryoni

Effect of temperature on survival of Australian entomopathogenic nematodes and their virulence against the Queensland fruit fly, Bactrocera tryoni

Susceptibility of white grubs from forestry and sugarcane plantations in South Africa to entomopathogenic nematodes

Molecular Identification and Phylogenetic Diversity of Native Entomopathogenic Nematodes, and Their Bacterial Endosymbionts, Isolated from Banana and Plantain Crops in Western Colombia

Contact Info

Product

Resources

About